1 // s390.cc -- s390 target support for gold.
2 
3 // Copyright (C) 2015-2016 Free Software Foundation, Inc.
4 // Written by Marcin Kościelnicki <koriakin@0x04.net>.
5 
6 // This file is part of gold.
7 
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
12 
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 // GNU General Public License for more details.
17 
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
22 
23 #include "gold.h"
24 
25 #include <cstring>
26 
27 #include "elfcpp.h"
28 #include "dwarf.h"
29 #include "parameters.h"
30 #include "reloc.h"
31 #include "s390.h"
32 #include "object.h"
33 #include "symtab.h"
34 #include "layout.h"
35 #include "output.h"
36 #include "copy-relocs.h"
37 #include "target.h"
38 #include "target-reloc.h"
39 #include "target-select.h"
40 #include "tls.h"
41 #include "gc.h"
42 #include "icf.h"
43 
44 namespace
45 {
46 
47 using namespace gold;
48 
49 // A class to handle the .got.plt section.
50 
51 template<int size>
52 class Output_data_got_plt_s390 : public Output_section_data_build
53 {
54  public:
Output_data_got_plt_s390(Layout * layout)55   Output_data_got_plt_s390(Layout* layout)
56     : Output_section_data_build(size/8),
57       layout_(layout)
58   { }
59 
Output_data_got_plt_s390(Layout * layout,off_t data_size)60   Output_data_got_plt_s390(Layout* layout, off_t data_size)
61     : Output_section_data_build(data_size, size/8),
62       layout_(layout)
63   { }
64 
65  protected:
66   // Write out the PLT data.
67   void
68   do_write(Output_file*);
69 
70   // Write to a map file.
71   void
do_print_to_mapfile(Mapfile * mapfile) const72   do_print_to_mapfile(Mapfile* mapfile) const
73   { mapfile->print_output_data(this, "** GOT PLT"); }
74 
75  private:
76   // A pointer to the Layout class, so that we can find the .dynamic
77   // section when we write out the GOT PLT section.
78   Layout* layout_;
79 };
80 
81 // A class to handle the PLT data.
82 
83 template<int size>
84 class Output_data_plt_s390 : public Output_section_data
85 {
86  public:
87   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, true>
88     Reloc_section;
89 
Output_data_plt_s390(Layout * layout,Output_data_got<size,true> * got,Output_data_got_plt_s390<size> * got_plt,Output_data_space * got_irelative)90   Output_data_plt_s390(Layout* layout,
91                          Output_data_got<size, true>* got,
92                          Output_data_got_plt_s390<size>* got_plt,
93                          Output_data_space* got_irelative)
94     : Output_section_data(4), layout_(layout),
95       irelative_rel_(NULL), got_(got), got_plt_(got_plt),
96       got_irelative_(got_irelative), count_(0),
97       irelative_count_(0), free_list_()
98   { this->init(layout); }
99 
Output_data_plt_s390(Layout * layout,Output_data_got<size,true> * got,Output_data_got_plt_s390<size> * got_plt,Output_data_space * got_irelative,unsigned int plt_count)100   Output_data_plt_s390(Layout* layout,
101                          Output_data_got<size, true>* got,
102                          Output_data_got_plt_s390<size>* got_plt,
103                          Output_data_space* got_irelative,
104                          unsigned int plt_count)
105     : Output_section_data((plt_count + 1) * plt_entry_size,
106                           4, false),
107       layout_(layout), irelative_rel_(NULL), got_(got),
108       got_plt_(got_plt), got_irelative_(got_irelative), count_(plt_count),
109       irelative_count_(0), free_list_()
110   {
111     this->init(layout);
112 
113     // Initialize the free list and reserve the first entry.
114     this->free_list_.init((plt_count + 1) * plt_entry_size, false);
115     this->free_list_.remove(0, plt_entry_size);
116   }
117 
118   // Initialize the PLT section.
119   void
120   init(Layout* layout);
121 
122   // Add an entry to the PLT.
123   void
124   add_entry(Symbol_table*, Layout*, Symbol* gsym);
125 
126   // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
127   unsigned int
128   add_local_ifunc_entry(Symbol_table*, Layout*,
129     Sized_relobj_file<size, true>*, unsigned int);
130 
131   // Add the relocation for a PLT entry.
132   void
133   add_relocation(Symbol_table*, Layout*, Symbol*, unsigned int);
134 
135   // Return the .rela.plt section data.
136   Reloc_section*
rela_plt()137   rela_plt()
138   { return this->rel_; }
139 
140   // Return where the IRELATIVE relocations should go in the PLT
141   // relocations.
142   Reloc_section*
143   rela_irelative(Symbol_table*, Layout*);
144 
145   // Return whether we created a section for IRELATIVE relocations.
146   bool
has_irelative_section() const147   has_irelative_section() const
148   { return this->irelative_rel_ != NULL; }
149 
150   // Return the number of PLT entries.
151   unsigned int
entry_count() const152   entry_count() const
153   { return this->count_ + this->irelative_count_; }
154 
155   // Return the offset of the first non-reserved PLT entry.
156   unsigned int
first_plt_entry_offset()157   first_plt_entry_offset()
158   { return plt_entry_size; }
159 
160   // Return the size of a PLT entry.
161   unsigned int
get_plt_entry_size() const162   get_plt_entry_size() const
163   { return plt_entry_size; }
164 
165   // Reserve a slot in the PLT for an existing symbol in an incremental update.
166   void
reserve_slot(unsigned int plt_index)167   reserve_slot(unsigned int plt_index)
168   {
169     this->free_list_.remove((plt_index + 1) * plt_entry_size,
170                             (plt_index + 2) * plt_entry_size);
171   }
172 
173   // Return the PLT address to use for a global symbol.
174   uint64_t
175   address_for_global(const Symbol*);
176 
177   // Return the PLT address to use for a local symbol.
178   uint64_t
179   address_for_local(const Relobj*, unsigned int symndx);
180 
181   // Add .eh_frame information for the PLT.
182   void
add_eh_frame(Layout * layout)183   add_eh_frame(Layout* layout)
184   {
185 	  (void)layout;
186     layout->add_eh_frame_for_plt(this,
187 				 plt_eh_frame_cie,
188 				 plt_eh_frame_cie_size,
189 				 plt_eh_frame_fde,
190 				 plt_eh_frame_fde_size);
191   }
192 
193  protected:
194   // Fill in the first PLT entry.
195   void
196   fill_first_plt_entry(unsigned char* pov,
197 		       typename elfcpp::Elf_types<size>::Elf_Addr got_address,
198 		       typename elfcpp::Elf_types<size>::Elf_Addr plt_address);
199 
200   // Fill in a normal PLT entry.  Returns the offset into the entry that
201   // should be the initial GOT slot value.
202   unsigned int
203   fill_plt_entry(unsigned char* pov,
204 		 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
205 		 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
206 		 unsigned int got_offset,
207 		 unsigned int plt_offset,
208 		 unsigned int plt_rel_offset);
209 
210   void
211   do_adjust_output_section(Output_section* os);
212 
213   // Write to a map file.
214   void
do_print_to_mapfile(Mapfile * mapfile) const215   do_print_to_mapfile(Mapfile* mapfile) const
216   { mapfile->print_output_data(this, _("** PLT")); }
217 
218  private:
219   // Set the final size.
220   void
221   set_final_data_size();
222 
223   // Write out the PLT data.
224   void
225   do_write(Output_file*);
226 
227   // A pointer to the Layout class, so that we can find the .dynamic
228   // section when we write out the GOT PLT section.
229   Layout* layout_;
230   // The reloc section.
231   Reloc_section* rel_;
232   // The IRELATIVE relocs, if necessary.  These must follow the
233   // regular PLT relocations.
234   Reloc_section* irelative_rel_;
235   // The .got section.
236   Output_data_got<size, true>* got_;
237   // The .got.plt section.
238   Output_data_got_plt_s390<size>* got_plt_;
239   // The part of the .got.plt section used for IRELATIVE relocs.
240   Output_data_space* got_irelative_;
241   // The number of PLT entries.
242   unsigned int count_;
243   // Number of PLT entries with R_TILEGX_IRELATIVE relocs.  These
244   // follow the regular PLT entries.
245   unsigned int irelative_count_;
246   // List of available regions within the section, for incremental
247   // update links.
248   Free_list free_list_;
249 
250   // The size of an entry in the PLT.
251   static const int plt_entry_size = 0x20;
252   // The first entry in the PLT.
253   static const unsigned char first_plt_entry_32_abs[plt_entry_size];
254   static const unsigned char first_plt_entry_32_pic[plt_entry_size];
255   static const unsigned char first_plt_entry_64[plt_entry_size];
256   // Other entries in the PLT for an executable.
257   static const unsigned char plt_entry_32_abs[plt_entry_size];
258   static const unsigned char plt_entry_32_pic12[plt_entry_size];
259   static const unsigned char plt_entry_32_pic16[plt_entry_size];
260   static const unsigned char plt_entry_32_pic[plt_entry_size];
261   static const unsigned char plt_entry_64[plt_entry_size];
262 
263   // The .eh_frame unwind information for the PLT.
264   static const int plt_eh_frame_cie_size = 12;
265   static const unsigned char plt_eh_frame_cie[plt_eh_frame_cie_size];
266   static const int plt_eh_frame_fde_size = 12;
267   static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
268 };
269 
270 
271 template<int size>
272 class Target_s390 : public Sized_target<size, true>
273 {
274  public:
275   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, true> Reloc_section;
276 
Target_s390()277   Target_s390()
278     : Sized_target<size, true>(&s390_info),
279       got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
280       global_offset_table_(NULL), rela_dyn_(NULL),
281       rela_irelative_(NULL), copy_relocs_(elfcpp::R_390_COPY),
282       got_mod_index_offset_(-1U), tls_base_symbol_defined_(false),
283       layout_(NULL)
284   { }
285 
286   // Scan the relocations to look for symbol adjustments.
287   void
288   gc_process_relocs(Symbol_table* symtab,
289 		    Layout* layout,
290 		    Sized_relobj_file<size, true>* object,
291 		    unsigned int data_shndx,
292 		    unsigned int sh_type,
293 		    const unsigned char* prelocs,
294 		    size_t reloc_count,
295 		    Output_section* output_section,
296 		    bool needs_special_offset_handling,
297 		    size_t local_symbol_count,
298 		    const unsigned char* plocal_symbols);
299 
300   // Scan the relocations to look for symbol adjustments.
301   void
302   scan_relocs(Symbol_table* symtab,
303 	      Layout* layout,
304 	      Sized_relobj_file<size, true>* object,
305 	      unsigned int data_shndx,
306 	      unsigned int sh_type,
307 	      const unsigned char* prelocs,
308 	      size_t reloc_count,
309 	      Output_section* output_section,
310 	      bool needs_special_offset_handling,
311 	      size_t local_symbol_count,
312 	      const unsigned char* plocal_symbols);
313 
314   // Finalize the sections.
315   void
316   do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
317 
318   // Return the value to use for a dynamic which requires special
319   // treatment.
320   uint64_t
321   do_dynsym_value(const Symbol*) const;
322 
323   // Relocate a section.
324   void
325   relocate_section(const Relocate_info<size, true>*,
326 		   unsigned int sh_type,
327 		   const unsigned char* prelocs,
328 		   size_t reloc_count,
329 		   Output_section* output_section,
330 		   bool needs_special_offset_handling,
331 		   unsigned char* view,
332 		   typename elfcpp::Elf_types<size>::Elf_Addr view_address,
333 		   section_size_type view_size,
334 		   const Reloc_symbol_changes*);
335 
336   // Scan the relocs during a relocatable link.
337   void
338   scan_relocatable_relocs(Symbol_table* symtab,
339 			  Layout* layout,
340 			  Sized_relobj_file<size, true>* object,
341 			  unsigned int data_shndx,
342 			  unsigned int sh_type,
343 			  const unsigned char* prelocs,
344 			  size_t reloc_count,
345 			  Output_section* output_section,
346 			  bool needs_special_offset_handling,
347 			  size_t local_symbol_count,
348 			  const unsigned char* plocal_symbols,
349 			  Relocatable_relocs*);
350 
351   // Scan the relocs for --emit-relocs.
352   void
353   emit_relocs_scan(Symbol_table* symtab,
354 		   Layout* layout,
355 		   Sized_relobj_file<size, true>* object,
356 		   unsigned int data_shndx,
357 		   unsigned int sh_type,
358 		   const unsigned char* prelocs,
359 		   size_t reloc_count,
360 		   Output_section* output_section,
361 		   bool needs_special_offset_handling,
362 		   size_t local_symbol_count,
363 		   const unsigned char* plocal_syms,
364 		   Relocatable_relocs* rr);
365 
366   // Return a string used to fill a code section with nops.
367   std::string
368   do_code_fill(section_size_type length) const;
369 
370   // Emit relocations for a section.
371   void
372   relocate_relocs(
373       const Relocate_info<size, true>*,
374       unsigned int sh_type,
375       const unsigned char* prelocs,
376       size_t reloc_count,
377       Output_section* output_section,
378       typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
379       unsigned char* view,
380       typename elfcpp::Elf_types<size>::Elf_Addr view_address,
381       section_size_type view_size,
382       unsigned char* reloc_view,
383       section_size_type reloc_view_size);
384 
385   // Return whether SYM is defined by the ABI.
386   bool
do_is_defined_by_abi(const Symbol * sym) const387   do_is_defined_by_abi(const Symbol* sym) const
388   { return strcmp(sym->name(), "__tls_get_offset") == 0; }
389 
390   // Return the PLT address to use for a global symbol.
391   uint64_t
do_plt_address_for_global(const Symbol * gsym) const392   do_plt_address_for_global(const Symbol* gsym) const
393   { return this->plt_section()->address_for_global(gsym); }
394 
395   uint64_t
do_plt_address_for_local(const Relobj * relobj,unsigned int symndx) const396   do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
397   { return this->plt_section()->address_for_local(relobj, symndx); }
398 
399   // Return the offset to use for the GOT_INDX'th got entry which is
400   // for a local tls symbol specified by OBJECT, SYMNDX.
401   int64_t
402   do_tls_offset_for_local(const Relobj* object,
403 			  unsigned int symndx,
404 			  unsigned int got_indx) const;
405 
406   // Return the offset to use for the GOT_INDX'th got entry which is
407   // for global tls symbol GSYM.
408   int64_t
409   do_tls_offset_for_global(Symbol* gsym, unsigned int got_indx) const;
410 
411   // This function should be defined in targets that can use relocation
412   // types to determine (implemented in local_reloc_may_be_function_pointer
413   // and global_reloc_may_be_function_pointer)
414   // if a function's pointer is taken.  ICF uses this in safe mode to only
415   // fold those functions whose pointer is defintely not taken.
416   bool
do_can_check_for_function_pointers() const417   do_can_check_for_function_pointers() const
418   { return true; }
419 
420   // Return whether SYM is call to a non-split function.
421   bool
422   do_is_call_to_non_split(const Symbol* sym, const unsigned char* preloc,
423 			  const unsigned char* view,
424 			  section_size_type view_size) const;
425 
426   // Adjust -fsplit-stack code which calls non-split-stack code.
427   void
428   do_calls_non_split(Relobj* object, unsigned int shndx,
429 		     section_offset_type fnoffset, section_size_type fnsize,
430 		     const unsigned char* prelocs, size_t reloc_count,
431 		     unsigned char* view, section_size_type view_size,
432 		     std::string* from, std::string* to) const;
433 
434   // Return the size of the GOT section.
435   section_size_type
got_size() const436   got_size() const
437   {
438     gold_assert(this->got_ != NULL);
439     return this->got_->data_size();
440   }
441 
442   // Return the number of entries in the GOT.
443   unsigned int
got_entry_count() const444   got_entry_count() const
445   {
446     if (this->got_ == NULL)
447       return 0;
448     return this->got_size() / (size / 8);
449   }
450 
451   // Return the number of entries in the PLT.
452   unsigned int
453   plt_entry_count() const;
454 
455   // Return the offset of the first non-reserved PLT entry.
456   unsigned int
457   first_plt_entry_offset() const;
458 
459   // Return the size of each PLT entry.
460   unsigned int
461   plt_entry_size() const;
462 
463   // Create the GOT section for an incremental update.
464   Output_data_got_base*
465   init_got_plt_for_update(Symbol_table* symtab,
466 			  Layout* layout,
467 			  unsigned int got_count,
468 			  unsigned int plt_count);
469 
470   // Reserve a GOT entry for a local symbol, and regenerate any
471   // necessary dynamic relocations.
472   void
473   reserve_local_got_entry(unsigned int got_index,
474 			  Sized_relobj<size, true>* obj,
475 			  unsigned int r_sym,
476 			  unsigned int got_type);
477 
478   // Reserve a GOT entry for a global symbol, and regenerate any
479   // necessary dynamic relocations.
480   void
481   reserve_global_got_entry(unsigned int got_index, Symbol* gsym,
482 			   unsigned int got_type);
483 
484   // Register an existing PLT entry for a global symbol.
485   void
486   register_global_plt_entry(Symbol_table*, Layout*, unsigned int plt_index,
487 			    Symbol* gsym);
488 
489   // Force a COPY relocation for a given symbol.
490   void
491   emit_copy_reloc(Symbol_table*, Symbol*, Output_section*, off_t);
492 
493   // Apply an incremental relocation.
494   void
495   apply_relocation(const Relocate_info<size, true>* relinfo,
496 		   typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
497 		   unsigned int r_type,
498 		   typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
499 		   const Symbol* gsym,
500 		   unsigned char* view,
501 		   typename elfcpp::Elf_types<size>::Elf_Addr address,
502 		   section_size_type view_size);
503 
504  private:
505 
506   // The class which scans relocations.
507   class Scan
508   {
509   public:
Scan()510     Scan()
511       : issued_non_pic_error_(false)
512     { }
513 
514     static inline int
515     get_reference_flags(unsigned int r_type);
516 
517     inline void
518     local(Symbol_table* symtab, Layout* layout, Target_s390* target,
519 	  Sized_relobj_file<size, true>* object,
520 	  unsigned int data_shndx,
521 	  Output_section* output_section,
522 	  const elfcpp::Rela<size, true>& reloc, unsigned int r_type,
523 	  const elfcpp::Sym<size, true>& lsym,
524 	  bool is_discarded);
525 
526     inline void
527     global(Symbol_table* symtab, Layout* layout, Target_s390* target,
528 	   Sized_relobj_file<size, true>* object,
529 	   unsigned int data_shndx,
530 	   Output_section* output_section,
531 	   const elfcpp::Rela<size, true>& reloc, unsigned int r_type,
532 	   Symbol* gsym);
533 
534     inline bool
535     local_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
536 					Target_s390* target,
537 					Sized_relobj_file<size, true>* object,
538 					unsigned int data_shndx,
539 					Output_section* output_section,
540 					const elfcpp::Rela<size, true>& reloc,
541 					unsigned int r_type,
542 					const elfcpp::Sym<size, true>& lsym);
543 
544     inline bool
545     global_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
546 					 Target_s390* target,
547 					 Sized_relobj_file<size, true>* object,
548 					 unsigned int data_shndx,
549 					 Output_section* output_section,
550 					 const elfcpp::Rela<size, true>& reloc,
551 					 unsigned int r_type,
552 					 Symbol* gsym);
553 
554   private:
555     static void
556     unsupported_reloc_local(Sized_relobj_file<size, true>*,
557 			    unsigned int r_type);
558 
559     static void
560     unsupported_reloc_global(Sized_relobj_file<size, true>*,
561 			     unsigned int r_type, Symbol*);
562 
563     void
564     check_non_pic(Relobj*, unsigned int r_type);
565 
566     inline bool
567     possible_function_pointer_reloc(unsigned int r_type);
568 
569     bool
570     reloc_needs_plt_for_ifunc(Sized_relobj_file<size, true>*,
571 			      unsigned int r_type);
572 
573     // Whether we have issued an error about a non-PIC compilation.
574     bool issued_non_pic_error_;
575   };
576 
577   // The class which implements relocation.
578   class Relocate
579   {
580    public:
581     // Do a relocation.  Return false if the caller should not issue
582     // any warnings about this relocation.
583     inline bool
584     relocate(const Relocate_info<size, true>*, unsigned int,
585 	     Target_s390*, Output_section*, size_t, const unsigned char*,
586 	     const Sized_symbol<size>*, const Symbol_value<size>*,
587 	     unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
588 	     section_size_type);
589 
590    private:
591     // Do a TLS relocation.
592     inline typename elfcpp::Elf_types<size>::Elf_Addr
593     relocate_tls(const Relocate_info<size, true>*, Target_s390*,
594 		 size_t relnum, const elfcpp::Rela<size, true>&,
595 		 unsigned int r_type, const Sized_symbol<size>*,
596 		 const Symbol_value<size>*,
597 		 unsigned char*, section_size_type);
598 
599     // Do a TLS General-Dynamic to Initial-Exec transition.
600     inline void
601     tls_gd_to_ie(const Relocate_info<size, true>*, size_t relnum,
602 		 const elfcpp::Rela<size, true>&,
603 		 unsigned char* view,
604 		 section_size_type view_size);
605 
606     // Do a TLS General-Dynamic to Local-Exec transition.
607     inline void
608     tls_gd_to_le(const Relocate_info<size, true>*, size_t relnum,
609 		 const elfcpp::Rela<size, true>&,
610 		 unsigned char* view,
611 		 section_size_type view_size);
612 
613     // Do a TLS Local-Dynamic to Local-Exec transition.
614     inline void
615     tls_ld_to_le(const Relocate_info<size, true>*, size_t relnum,
616 		 const elfcpp::Rela<size, true>&,
617 		 unsigned char* view,
618 		 section_size_type view_size);
619 
620     // Do a TLS Initial-Exec to Local-Exec transition.
621     static inline void
622     tls_ie_to_le(const Relocate_info<size, true>*, size_t relnum,
623 		 const elfcpp::Rela<size, true>&,
624 		 unsigned char* view,
625 		 section_size_type view_size);
626   };
627 
628   // Adjust TLS relocation type based on the options and whether this
629   // is a local symbol.
630   static tls::Tls_optimization
631   optimize_tls_reloc(bool is_final, int r_type);
632 
633   // Get the GOT section.
634   const Output_data_got<size, true>*
got_section() const635   got_section() const
636   {
637     gold_assert(this->got_ != NULL);
638     return this->got_;
639   }
640 
641   // Get the GOT section, creating it if necessary.
642   Output_data_got<size, true>*
643   got_section(Symbol_table*, Layout*);
644 
645   typename elfcpp::Elf_types<size>::Elf_Addr
got_address() const646   got_address() const
647   {
648     gold_assert(this->got_ != NULL);
649     return this->got_plt_->address();
650   }
651 
652   typename elfcpp::Elf_types<size>::Elf_Addr
got_main_offset() const653   got_main_offset() const
654   {
655     gold_assert(this->got_ != NULL);
656     return this->got_->address() - this->got_address();
657   }
658 
659   // Create the PLT section.
660   void
661   make_plt_section(Symbol_table* symtab, Layout* layout);
662 
663   // Create a PLT entry for a global symbol.
664   void
665   make_plt_entry(Symbol_table*, Layout*, Symbol*);
666 
667   // Create a PLT entry for a local STT_GNU_IFUNC symbol.
668   void
669   make_local_ifunc_plt_entry(Symbol_table*, Layout*,
670 			     Sized_relobj_file<size, true>* relobj,
671 			     unsigned int local_sym_index);
672 
673   // Create a GOT entry for the TLS module index.
674   unsigned int
675   got_mod_index_entry(Symbol_table* symtab, Layout* layout,
676 		      Sized_relobj_file<size, true>* object);
677 
678   // Get the PLT section.
679   Output_data_plt_s390<size>*
plt_section() const680   plt_section() const
681   {
682     gold_assert(this->plt_ != NULL);
683     return this->plt_;
684   }
685 
686   // Get the dynamic reloc section, creating it if necessary.
687   Reloc_section*
688   rela_dyn_section(Layout*);
689 
690   // Get the section to use for IRELATIVE relocations.
691   Reloc_section*
692   rela_irelative_section(Layout*);
693 
694   // Add a potential copy relocation.
695   void
copy_reloc(Symbol_table * symtab,Layout * layout,Sized_relobj_file<size,true> * object,unsigned int shndx,Output_section * output_section,Symbol * sym,const elfcpp::Rela<size,true> & reloc)696   copy_reloc(Symbol_table* symtab, Layout* layout,
697 	     Sized_relobj_file<size, true>* object,
698 	     unsigned int shndx, Output_section* output_section,
699 	     Symbol* sym, const elfcpp::Rela<size, true>& reloc)
700   {
701     unsigned int r_type = elfcpp::elf_r_type<size>(reloc.get_r_info());
702     this->copy_relocs_.copy_reloc(symtab, layout,
703 				  symtab->get_sized_symbol<size>(sym),
704 				  object, shndx, output_section,
705 				  r_type, reloc.get_r_offset(),
706 				  reloc.get_r_addend(),
707 				  this->rela_dyn_section(layout));
708   }
709 
710   // A function for targets to call.  Return whether BYTES/LEN matches
711   // VIEW/VIEW_SIZE at OFFSET.  Like the one in Target, but takes
712   // an unsigned char * parameter.
713   bool
match_view_u(const unsigned char * view,section_size_type view_size,section_offset_type offset,const unsigned char * bytes,size_t len) const714   match_view_u(const unsigned char* view, section_size_type view_size,
715      section_offset_type offset, const unsigned char* bytes, size_t len) const
716     {
717       return this->match_view(view, view_size, offset,
718 			      reinterpret_cast<const char*>(bytes), len);
719     }
720 
721   // Information about this specific target which we pass to the
722   // general Target structure.
723   static Target::Target_info s390_info;
724 
725   // The types of GOT entries needed for this platform.
726   // These values are exposed to the ABI in an incremental link.
727   // Do not renumber existing values without changing the version
728   // number of the .gnu_incremental_inputs section.
729   enum Got_type
730   {
731     GOT_TYPE_STANDARD = 0,      // GOT entry for a regular symbol
732     GOT_TYPE_TLS_OFFSET = 1,    // GOT entry for TLS offset
733     GOT_TYPE_TLS_PAIR = 2,      // GOT entry for TLS module/offset pair
734   };
735 
736   // The GOT section.
737   Output_data_got<size, true>* got_;
738   // The PLT section.
739   Output_data_plt_s390<size>* plt_;
740   // The GOT PLT section.
741   Output_data_got_plt_s390<size>* got_plt_;
742   // The GOT section for IRELATIVE relocations.
743   Output_data_space* got_irelative_;
744   // The _GLOBAL_OFFSET_TABLE_ symbol.
745   Symbol* global_offset_table_;
746   // The dynamic reloc section.
747   Reloc_section* rela_dyn_;
748   // The section to use for IRELATIVE relocs.
749   Reloc_section* rela_irelative_;
750   // Relocs saved to avoid a COPY reloc.
751   Copy_relocs<elfcpp::SHT_RELA, size, true> copy_relocs_;
752   // Offset of the GOT entry for the TLS module index.
753   unsigned int got_mod_index_offset_;
754   // True if the _TLS_MODULE_BASE_ symbol has been defined.
755   bool tls_base_symbol_defined_;
756   // For use in do_tls_offset_for_*
757   Layout *layout_;
758 
759   // Code sequences for -fsplit-stack matching.
760   static const unsigned char ss_code_bras_8[];
761   static const unsigned char ss_code_l_basr[];
762   static const unsigned char ss_code_a_basr[];
763   static const unsigned char ss_code_larl[];
764   static const unsigned char ss_code_brasl[];
765   static const unsigned char ss_code_jg[];
766   static const unsigned char ss_code_jgl[];
767 
768   // Variable code sequence matchers for -fsplit-stack.
769   bool ss_match_st_r14(unsigned char* view,
770 		       section_size_type view_size,
771 		       section_offset_type *offset) const;
772   bool ss_match_l_r14(unsigned char* view,
773 		      section_size_type view_size,
774 		      section_offset_type *offset) const;
775   bool ss_match_mcount(unsigned char* view,
776 		       section_size_type view_size,
777 		       section_offset_type *offset) const;
778   bool ss_match_ear(unsigned char* view,
779 		    section_size_type view_size,
780 		    section_offset_type *offset) const;
781   bool ss_match_c(unsigned char* view,
782 		  section_size_type view_size,
783 		  section_offset_type *offset) const;
784   bool ss_match_l(unsigned char* view,
785 		  section_size_type view_size,
786 		  section_offset_type *offset,
787 		  int *guard_reg) const;
788   bool ss_match_ahi(unsigned char* view,
789 		    section_size_type view_size,
790 		    section_offset_type *offset,
791 		    int guard_reg,
792 		    uint32_t *arg) const;
793   bool ss_match_alfi(unsigned char* view,
794 		     section_size_type view_size,
795 		     section_offset_type *offset,
796 		     int guard_reg,
797 		     uint32_t *arg) const;
798   bool ss_match_cr(unsigned char* view,
799 		   section_size_type view_size,
800 		   section_offset_type *offset,
801 		   int guard_reg) const;
802 };
803 
804 template<>
805 Target::Target_info Target_s390<32>::s390_info =
806 {
807   32,			// size
808   true,			// is_big_endian
809   elfcpp::EM_S390,	// machine_code
810   false,		// has_make_symbol
811   false,		// has_resolve
812   true,			// has_code_fill
813   true,			// is_default_stack_executable
814   true,			// can_icf_inline_merge_sections
815   '\0',			// wrap_char
816   "/lib/ld.so.1",	// dynamic_linker
817   0x00400000,		// default_text_segment_address
818   4 * 1024,		// abi_pagesize (overridable by -z max-page-size)
819   4 * 1024,		// common_pagesize (overridable by -z common-page-size)
820   false,                // isolate_execinstr
821   0,                    // rosegment_gap
822   elfcpp::SHN_UNDEF,	// small_common_shndx
823   elfcpp::SHN_UNDEF,	// large_common_shndx
824   0,			// small_common_section_flags
825   0,			// large_common_section_flags
826   NULL,			// attributes_section
827   NULL,			// attributes_vendor
828   "_start",		// entry_symbol_name
829   32,			// hash_entry_size
830 };
831 
832 template<>
833 Target::Target_info Target_s390<64>::s390_info =
834 {
835   64,			// size
836   true,			// is_big_endian
837   elfcpp::EM_S390,	// machine_code
838   false,		// has_make_symbol
839   false,		// has_resolve
840   true,			// has_code_fill
841   true,			// is_default_stack_executable
842   true,			// can_icf_inline_merge_sections
843   '\0',			// wrap_char
844   "/lib/ld64.so.1",	// dynamic_linker
845   0x80000000ll,		// default_text_segment_address
846   4 * 1024,		// abi_pagesize (overridable by -z max-page-size)
847   4 * 1024,		// common_pagesize (overridable by -z common-page-size)
848   false,                // isolate_execinstr
849   0,                    // rosegment_gap
850   elfcpp::SHN_UNDEF,	// small_common_shndx
851   elfcpp::SHN_UNDEF,	// large_common_shndx
852   0,			// small_common_section_flags
853   0,			// large_common_section_flags
854   NULL,			// attributes_section
855   NULL,			// attributes_vendor
856   "_start",		// entry_symbol_name
857   64,			// hash_entry_size
858 };
859 
860 template<int size>
861 class S390_relocate_functions
862 {
863 public:
864   enum Overflow_check
865   {
866     CHECK_NONE,
867     CHECK_SIGNED,
868     CHECK_UNSIGNED,
869     CHECK_BITFIELD,
870     CHECK_LOW_INSN,
871     CHECK_HIGH_INSN
872   };
873 
874   enum Status
875   {
876     STATUS_OK,
877     STATUS_OVERFLOW
878   };
879 
880 private:
881   typedef S390_relocate_functions<size> This;
882   typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
883 
884   template<int valsize>
885   static inline bool
has_overflow_signed(Address value)886   has_overflow_signed(Address value)
887   {
888     // limit = 1 << (valsize - 1) without shift count exceeding size of type
889     Address limit = static_cast<Address>(1) << ((valsize - 1) >> 1);
890     limit <<= ((valsize - 1) >> 1);
891     limit <<= ((valsize - 1) - 2 * ((valsize - 1) >> 1));
892     return value + limit > (limit << 1) - 1;
893   }
894 
895   template<int valsize>
896   static inline bool
has_overflow_unsigned(Address value)897   has_overflow_unsigned(Address value)
898   {
899     Address limit = static_cast<Address>(1) << ((valsize - 1) >> 1);
900     limit <<= ((valsize - 1) >> 1);
901     limit <<= ((valsize - 1) - 2 * ((valsize - 1) >> 1));
902     return value > (limit << 1) - 1;
903   }
904 
905   template<int fieldsize>
906   static inline void
rela(unsigned char * view,Address mask,Address value)907   rela(unsigned char* view, Address mask, Address value)
908   {
909     typedef typename elfcpp::Swap<fieldsize, true>::Valtype Valtype;
910     Valtype* wv = reinterpret_cast<Valtype*>(view);
911     Valtype val = elfcpp::Swap<fieldsize, true>::readval(view);
912     val &= ~mask;
913     value &= mask;
914     elfcpp::Swap<fieldsize, true>::writeval(wv, val | value);
915   }
916 
917 public:
918   // R_390_12, R_390_GOT12, R_390_GOTPLT12, R_390_GOTIE12
919   static inline Status
rela12(unsigned char * view,Address value)920   rela12(unsigned char* view, Address value)
921   {
922     if (This::template has_overflow_unsigned<12>(value))
923       return STATUS_OVERFLOW;
924     This::template rela<16>(view, 0x0fff, value);
925     return STATUS_OK;
926   }
927 
928   // R_390_16, R_390_GOT16, R_390_GOTPLT16, R_390_GOTOFF16, R_390_PLTOFF16
929   static inline Status
rela16(unsigned char * view,Address value)930   rela16(unsigned char* view, Address value)
931   {
932     if (This::template has_overflow_signed<16>(value))
933       return STATUS_OVERFLOW;
934     This::template rela<16>(view, 0xffff, value);
935     return STATUS_OK;
936   }
937 
938   // R_390_20, R_390_GOT20, R_390_GOTPLT20, R_390_GOTIE20
939   static inline Status
rela20(unsigned char * view,Address value)940   rela20(unsigned char* view, Address value)
941   {
942     if (This::template has_overflow_signed<20>(value))
943       return STATUS_OVERFLOW;
944     This::template rela<16>(view, 0x0fff, value);
945     This::template rela<16>(view + 2, 0xff00, value >> (12 - 8));
946     return STATUS_OK;
947   }
948 
949   // R_390_PC12DBL, R_390_PLT12DBL
950   static inline Status
pcrela12dbl(unsigned char * view,Address value,Address address)951   pcrela12dbl(unsigned char* view, Address value, Address address)
952   {
953     value -= address;
954     if ((value & 1) != 0)
955       return STATUS_OVERFLOW;
956     if (This::template has_overflow_signed<13>(value))
957       return STATUS_OVERFLOW;
958     value >>= 1;
959     This::template rela<16>(view, 0x0fff, value);
960     return STATUS_OK;
961   }
962 
963   // R_390_PC16DBL, R_390_PLT16DBL
964   static inline Status
pcrela16dbl(unsigned char * view,Address value,Address address)965   pcrela16dbl(unsigned char* view, Address value, Address address)
966   {
967     value -= address;
968     if ((value & 1) != 0)
969       return STATUS_OVERFLOW;
970     if (This::template has_overflow_signed<17>(value))
971       return STATUS_OVERFLOW;
972     value >>= 1;
973     This::template rela<16>(view, 0xffff, value);
974     return STATUS_OK;
975   }
976 
977   // R_390_PC24DBL, R_390_PLT24DBL
978   static inline Status
pcrela24dbl(unsigned char * view,Address value,Address address)979   pcrela24dbl(unsigned char* view, Address value, Address address)
980   {
981     value -= address;
982     if ((value & 1) != 0)
983       return STATUS_OVERFLOW;
984     if (This::template has_overflow_signed<25>(value))
985       return STATUS_OVERFLOW;
986     value >>= 1;
987     // Swap doesn't take 24-bit fields well...
988     This::template rela<8>(view, 0xff, value >> 16);
989     This::template rela<16>(view + 1, 0xffff, value);
990     return STATUS_OK;
991   }
992 
993   // R_390_PC32DBL, R_390_PLT32DBL, R_390_GOTPCDBL, R_390_GOTENT, R_390_GOTPLTENT
994   static inline Status
pcrela32dbl(unsigned char * view,Address value,Address address)995   pcrela32dbl(unsigned char* view, Address value, Address address)
996   {
997     Address reloc = value - address;
998     if ((reloc & 1) != 0)
999       {
1000 	gold_warning(_("R_390_PC32DBL target misaligned at %llx"), (long long)address);
1001 	// Wait for a fix for https://sourceware.org/bugzilla/show_bug.cgi?id=18960
1002 	// return STATUS_OVERFLOW;
1003       }
1004     if (This::template has_overflow_signed<33>(reloc))
1005       return STATUS_OVERFLOW;
1006     reloc >>= 1;
1007     if (value < address && size == 32)
1008       reloc |= 0x80000000;
1009     This::template rela<32>(view, 0xffffffff, reloc);
1010     return STATUS_OK;
1011   }
1012 
1013 };
1014 
1015 // Initialize the PLT section.
1016 
1017 template<int size>
1018 void
init(Layout * layout)1019 Output_data_plt_s390<size>::init(Layout* layout)
1020 {
1021   this->rel_ = new Reloc_section(false);
1022   layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1023 				  elfcpp::SHF_ALLOC, this->rel_,
1024 				  ORDER_DYNAMIC_PLT_RELOCS, false);
1025 }
1026 
1027 template<int size>
1028 void
do_adjust_output_section(Output_section * os)1029 Output_data_plt_s390<size>::do_adjust_output_section(Output_section* os)
1030 {
1031   os->set_entsize(plt_entry_size);
1032 }
1033 
1034 // Add an entry to the PLT.
1035 
1036 template<int size>
1037 void
add_entry(Symbol_table * symtab,Layout * layout,Symbol * gsym)1038 Output_data_plt_s390<size>::add_entry(Symbol_table* symtab, Layout* layout,
1039 					Symbol* gsym)
1040 {
1041   gold_assert(!gsym->has_plt_offset());
1042 
1043   unsigned int plt_index;
1044   off_t plt_offset;
1045   section_offset_type got_offset;
1046 
1047   unsigned int* pcount;
1048   unsigned int offset;
1049   unsigned int reserved;
1050   Output_section_data_build* got;
1051   if (gsym->type() == elfcpp::STT_GNU_IFUNC
1052       && gsym->can_use_relative_reloc(false))
1053     {
1054       pcount = &this->irelative_count_;
1055       offset = 0;
1056       reserved = 0;
1057       got = this->got_irelative_;
1058     }
1059   else
1060     {
1061       pcount = &this->count_;
1062       offset = 1;
1063       reserved = 3;
1064       got = this->got_plt_;
1065     }
1066 
1067   if (!this->is_data_size_valid())
1068     {
1069       // Note that when setting the PLT offset for a non-IRELATIVE
1070       // entry we skip the initial reserved PLT entry.
1071       plt_index = *pcount + offset;
1072       plt_offset = plt_index * plt_entry_size;
1073 
1074       ++*pcount;
1075 
1076       got_offset = (plt_index - offset + reserved) * size / 8;
1077       gold_assert(got_offset == got->current_data_size());
1078 
1079       // Every PLT entry needs a GOT entry which points back to the PLT
1080       // entry (this will be changed by the dynamic linker, normally
1081       // lazily when the function is called).
1082       got->set_current_data_size(got_offset + size / 8);
1083     }
1084   else
1085     {
1086       // FIXME: This is probably not correct for IRELATIVE relocs.
1087 
1088       // For incremental updates, find an available slot.
1089       plt_offset = this->free_list_.allocate(plt_entry_size,
1090 					     plt_entry_size, 0);
1091       if (plt_offset == -1)
1092 	gold_fallback(_("out of patch space (PLT);"
1093 			" relink with --incremental-full"));
1094 
1095       // The GOT and PLT entries have a 1-1 correspondance, so the GOT offset
1096       // can be calculated from the PLT index, adjusting for the three
1097       // reserved entries at the beginning of the GOT.
1098       plt_index = plt_offset / plt_entry_size - 1;
1099       got_offset = (plt_index - offset + reserved) * size / 8;
1100     }
1101 
1102   gsym->set_plt_offset(plt_offset);
1103 
1104   // Every PLT entry needs a reloc.
1105   this->add_relocation(symtab, layout, gsym, got_offset);
1106 
1107   // Note that we don't need to save the symbol.  The contents of the
1108   // PLT are independent of which symbols are used.  The symbols only
1109   // appear in the relocations.
1110 }
1111 
1112 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.  Return
1113 // the PLT offset.
1114 
1115 template<int size>
1116 unsigned int
add_local_ifunc_entry(Symbol_table * symtab,Layout * layout,Sized_relobj_file<size,true> * relobj,unsigned int local_sym_index)1117 Output_data_plt_s390<size>::add_local_ifunc_entry(
1118     Symbol_table* symtab,
1119     Layout* layout,
1120     Sized_relobj_file<size, true>* relobj,
1121     unsigned int local_sym_index)
1122 {
1123   unsigned int plt_offset = this->irelative_count_ * plt_entry_size;
1124   ++this->irelative_count_;
1125 
1126   section_offset_type got_offset = this->got_irelative_->current_data_size();
1127 
1128   // Every PLT entry needs a GOT entry which points back to the PLT
1129   // entry.
1130   this->got_irelative_->set_current_data_size(got_offset + size / 8);
1131 
1132   // Every PLT entry needs a reloc.
1133   Reloc_section* rela = this->rela_irelative(symtab, layout);
1134   rela->add_symbolless_local_addend(relobj, local_sym_index,
1135 				    elfcpp::R_390_IRELATIVE,
1136 				    this->got_irelative_, got_offset, 0);
1137 
1138   return plt_offset;
1139 }
1140 
1141 // Add the relocation for a PLT entry.
1142 
1143 template<int size>
1144 void
add_relocation(Symbol_table * symtab,Layout * layout,Symbol * gsym,unsigned int got_offset)1145 Output_data_plt_s390<size>::add_relocation(Symbol_table* symtab,
1146 					     Layout* layout,
1147 					     Symbol* gsym,
1148 					     unsigned int got_offset)
1149 {
1150   if (gsym->type() == elfcpp::STT_GNU_IFUNC
1151       && gsym->can_use_relative_reloc(false))
1152     {
1153       Reloc_section* rela = this->rela_irelative(symtab, layout);
1154       rela->add_symbolless_global_addend(gsym, elfcpp::R_390_IRELATIVE,
1155 					 this->got_irelative_, got_offset, 0);
1156     }
1157   else
1158     {
1159       gsym->set_needs_dynsym_entry();
1160       this->rel_->add_global(gsym, elfcpp::R_390_JMP_SLOT, this->got_plt_,
1161 			     got_offset, 0);
1162     }
1163 }
1164 
1165 // Return where the IRELATIVE relocations should go in the PLT.  These
1166 // follow the JUMP_SLOT and the TLSDESC relocations.
1167 
1168 template<int size>
1169 typename Output_data_plt_s390<size>::Reloc_section*
rela_irelative(Symbol_table * symtab,Layout * layout)1170 Output_data_plt_s390<size>::rela_irelative(Symbol_table* symtab,
1171 					     Layout* layout)
1172 {
1173   if (this->irelative_rel_ == NULL)
1174     {
1175       this->irelative_rel_ = new Reloc_section(false);
1176       layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1177 				      elfcpp::SHF_ALLOC, this->irelative_rel_,
1178 				      ORDER_DYNAMIC_PLT_RELOCS, false);
1179       gold_assert(this->irelative_rel_->output_section()
1180 		  == this->rel_->output_section());
1181 
1182       if (parameters->doing_static_link())
1183 	{
1184 	  // A statically linked executable will only have a .rela.plt
1185 	  // section to hold R_390_IRELATIVE relocs for
1186 	  // STT_GNU_IFUNC symbols.  The library will use these
1187 	  // symbols to locate the IRELATIVE relocs at program startup
1188 	  // time.
1189 	  symtab->define_in_output_data("__rela_iplt_start", NULL,
1190 					Symbol_table::PREDEFINED,
1191 					this->irelative_rel_, 0, 0,
1192 					elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1193 					elfcpp::STV_HIDDEN, 0, false, true);
1194 	  symtab->define_in_output_data("__rela_iplt_end", NULL,
1195 					Symbol_table::PREDEFINED,
1196 					this->irelative_rel_, 0, 0,
1197 					elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1198 					elfcpp::STV_HIDDEN, 0, true, true);
1199 	}
1200     }
1201   return this->irelative_rel_;
1202 }
1203 
1204 // Return the PLT address to use for a global symbol.
1205 
1206 template<int size>
1207 uint64_t
address_for_global(const Symbol * gsym)1208 Output_data_plt_s390<size>::address_for_global(const Symbol* gsym)
1209 {
1210   uint64_t offset = 0;
1211   if (gsym->type() == elfcpp::STT_GNU_IFUNC
1212       && gsym->can_use_relative_reloc(false))
1213     offset = (this->count_ + 1) * plt_entry_size;
1214   return this->address() + offset + gsym->plt_offset();
1215 }
1216 
1217 // Return the PLT address to use for a local symbol.  These are always
1218 // IRELATIVE relocs.
1219 
1220 template<int size>
1221 uint64_t
address_for_local(const Relobj * object,unsigned int r_sym)1222 Output_data_plt_s390<size>::address_for_local(const Relobj* object,
1223 						unsigned int r_sym)
1224 {
1225   return (this->address()
1226 	  + (this->count_ + 1) * plt_entry_size
1227 	  + object->local_plt_offset(r_sym));
1228 }
1229 
1230 // Set the final size.
1231 template<int size>
1232 void
set_final_data_size()1233 Output_data_plt_s390<size>::set_final_data_size()
1234 {
1235   unsigned int count = this->count_ + this->irelative_count_;
1236   this->set_data_size((count + 1) * plt_entry_size);
1237 }
1238 
1239 template<int size>
1240 const unsigned char
1241 Output_data_plt_s390<size>::first_plt_entry_32_abs[plt_entry_size] =
1242 {
1243   0x50, 0x10, 0xf0, 0x1c, // st %r1, 28(%r15)
1244   0x0d, 0x10, // basr %r1, %r0
1245   0x58, 0x10, 0x10, 0x12, // l %r1, 18(%r1)
1246   0xd2, 0x03, 0xf0, 0x18, 0x10, 0x04, // mvc 24(4,%r15), 4(%r1)
1247   0x58, 0x10, 0x10, 0x08, // l %r1, 8(%r1)
1248   0x07, 0xf1, // br %r1
1249   0x00, 0x00, // padding
1250   0x00, 0x00, 0x00, 0x00, // _GLOBAL_OFFSET_TABLE_ (to fill)
1251   0x00, 0x00, 0x00, 0x00, // padding
1252 };
1253 
1254 template<int size>
1255 const unsigned char
1256 Output_data_plt_s390<size>::first_plt_entry_32_pic[plt_entry_size] =
1257 {
1258   0x50, 0x10, 0xf0, 0x1c, // st %r1, 28(%r15)
1259   0x58, 0x10, 0xc0, 0x04, // l %r1, 4(%r12)
1260   0x50, 0x10, 0xf0, 0x18, // st %r1, 24(%r15)
1261   0x58, 0x10, 0xc0, 0x08, // l %r1, 8(%r12)
1262   0x07, 0xf1, // br %r1
1263   0x00, 0x00, // padding
1264   0x00, 0x00, 0x00, 0x00, // padding
1265   0x00, 0x00, 0x00, 0x00, // padding
1266   0x00, 0x00, 0x00, 0x00, // padding
1267 };
1268 
1269 template<int size>
1270 const unsigned char
1271 Output_data_plt_s390<size>::first_plt_entry_64[plt_entry_size] =
1272 {
1273   0xe3, 0x10, 0xf0, 0x38, 0x00, 0x24, // stg %r1, 56(%r15)
1274   0xc0, 0x10, 0x00, 0x00, 0x00, 0x00, // larl %r1, _GLOBAL_OFFSET_TABLE_ (to fill)
1275   0xd2, 0x07, 0xf0, 0x30, 0x10, 0x08, // mvc 48(8,%r15), 8(%r1)
1276   0xe3, 0x10, 0x10, 0x10, 0x00, 0x04, // lg %r1, 16(%r1)
1277   0x07, 0xf1, // br %r1
1278   0x07, 0x00, // nopr
1279   0x07, 0x00, // nopr
1280   0x07, 0x00, // nopr
1281 };
1282 
1283 template<int size>
1284 void
fill_first_plt_entry(unsigned char * pov,typename elfcpp::Elf_types<size>::Elf_Addr got_address,typename elfcpp::Elf_types<size>::Elf_Addr plt_address)1285 Output_data_plt_s390<size>::fill_first_plt_entry(
1286     unsigned char* pov,
1287     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1288     typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
1289 {
1290   if (size == 64)
1291     {
1292       memcpy(pov, first_plt_entry_64, plt_entry_size);
1293       S390_relocate_functions<size>::pcrela32dbl(pov + 8, got_address, (plt_address + 6));
1294     }
1295   else if (!parameters->options().output_is_position_independent())
1296     {
1297       memcpy(pov, first_plt_entry_32_abs, plt_entry_size);
1298       elfcpp::Swap<32, true>::writeval(pov + 24, got_address);
1299     }
1300   else
1301     {
1302       memcpy(pov, first_plt_entry_32_pic, plt_entry_size);
1303     }
1304 }
1305 
1306 template<int size>
1307 const unsigned char
1308 Output_data_plt_s390<size>::plt_entry_32_abs[plt_entry_size] =
1309 {
1310   // first part
1311   0x0d, 0x10, // basr %r1, %r0
1312   0x58, 0x10, 0x10, 0x16, // l %r1, 22(%r1)
1313   0x58, 0x10, 0x10, 0x00, // l %r1, 0(%r1)
1314   0x07, 0xf1, // br %r1
1315   // second part
1316   0x0d, 0x10, // basr %r1, %r0
1317   0x58, 0x10, 0x10, 0x0e, // l %r1, 14(%r1)
1318   0xa7, 0xf4, 0x00, 0x00, // j first_plt_entry (to fill)
1319   0x00, 0x00, // padding
1320   0x00, 0x00, 0x00, 0x00, // _GLOBAL_OFFSET_TABLE_+sym@gotplt (to fill)
1321   0x00, 0x00, 0x00, 0x00, // offset of relocation in .rela.plt (to fill)
1322 };
1323 
1324 template<int size>
1325 const unsigned char
1326 Output_data_plt_s390<size>::plt_entry_32_pic12[plt_entry_size] =
1327 {
1328   // first part
1329   0x58, 0x10, 0xc0, 0x00, // l %r1, sym@gotplt(%r12) (to fill)
1330   0x07, 0xf1, // br %r1
1331   0x00, 0x00, // padding
1332   0x00, 0x00, 0x00, 0x00, // padding
1333   // second part
1334   0x0d, 0x10, // basr %r1, %r0
1335   0x58, 0x10, 0x10, 0x0e, // l %r1, 14(%r1)
1336   0xa7, 0xf4, 0x00, 0x00, // j first_plt_entry (to fill)
1337   0x00, 0x00, // padding
1338   0x00, 0x00, 0x00, 0x00, // padding
1339   0x00, 0x00, 0x00, 0x00, // offset of relocation in .rela.plt (to fill)
1340 };
1341 
1342 template<int size>
1343 const unsigned char
1344 Output_data_plt_s390<size>::plt_entry_32_pic16[plt_entry_size] =
1345 {
1346   // first part
1347   0xa7, 0x18, 0x00, 0x00, // lhi %r1, sym@gotplt (to fill)
1348   0x58, 0x11, 0xc0, 0x00, // l %r1, 0(%r1, %r12)
1349   0x07, 0xf1, // br %r1
1350   0x00, 0x00, // padding
1351   // second part
1352   0x0d, 0x10, // basr %r1, %r0
1353   0x58, 0x10, 0x10, 0x0e, // l %r1, 14(%r1)
1354   0xa7, 0xf4, 0x00, 0x00, // j first_plt_entry (to fill)
1355   0x00, 0x00, // padding
1356   0x00, 0x00, 0x00, 0x00, // padding
1357   0x00, 0x00, 0x00, 0x00, // offset of relocation in .rela.plt (to fill)
1358 };
1359 
1360 template<int size>
1361 const unsigned char
1362 Output_data_plt_s390<size>::plt_entry_32_pic[plt_entry_size] =
1363 {
1364   // first part
1365   0x0d, 0x10, // basr %r1, %r0
1366   0x58, 0x10, 0x10, 0x16, // l %r1, 22(%r1)
1367   0x58, 0x11, 0xc0, 0x00, // l %r1, 0(%r1, %r12)
1368   0x07, 0xf1, // br %r1
1369   // second part
1370   0x0d, 0x10, // basr %r1, %r0
1371   0x58, 0x10, 0x10, 0x0e, // l %r1, 14(%r1)
1372   0xa7, 0xf4, 0x00, 0x00, // j first_plt_entry (to fill)
1373   0x00, 0x00, // padding
1374   0x00, 0x00, 0x00, 0x00, // sym@gotplt (to fill)
1375   0x00, 0x00, 0x00, 0x00, // offset of relocation in .rela.plt (to fill)
1376 };
1377 
1378 template<int size>
1379 const unsigned char
1380 Output_data_plt_s390<size>::plt_entry_64[plt_entry_size] =
1381 {
1382   // first part
1383   0xc0, 0x10, 0x00, 0x00, 0x00, 0x00, // larl %r1, _GLOBAL_OFFSET_TABLE_+off (to fill)
1384   0xe3, 0x10, 0x10, 0x00, 0x00, 0x04, // lg %r1, 0(%r1)
1385   0x07, 0xf1, // br %r1
1386   // second part
1387   0x0d, 0x10, // basr %r1, %r0
1388   0xe3, 0x10, 0x10, 0x0c, 0x00, 0x14, // lgf %r1, 12(%r1)
1389   0xc0, 0xf4, 0x00, 0x00, 0x00, 0x00, // jg first_plt_entry (to fill)
1390   0x00, 0x00, 0x00, 0x00, // offset of relocation in .rela.plt (to fill)
1391 };
1392 
1393 template<int size>
1394 unsigned int
fill_plt_entry(unsigned char * pov,typename elfcpp::Elf_types<size>::Elf_Addr got_address,typename elfcpp::Elf_types<size>::Elf_Addr plt_address,unsigned int got_offset,unsigned int plt_offset,unsigned int plt_rel_offset)1395 Output_data_plt_s390<size>::fill_plt_entry(
1396     unsigned char* pov,
1397     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1398     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
1399     unsigned int got_offset,
1400     unsigned int plt_offset,
1401     unsigned int plt_rel_offset)
1402 {
1403   if (size == 64)
1404   {
1405     memcpy(pov, plt_entry_64, plt_entry_size);
1406     S390_relocate_functions<size>::pcrela32dbl(pov + 2, got_address + got_offset, plt_address + plt_offset);
1407     S390_relocate_functions<size>::pcrela32dbl(pov + 24, plt_address, plt_address + plt_offset + 22);
1408   }
1409   else
1410   {
1411     if (!parameters->options().output_is_position_independent())
1412       {
1413 	memcpy(pov, plt_entry_32_abs, plt_entry_size);
1414 	elfcpp::Swap<32, true>::writeval(pov + 24, got_address + got_offset);
1415       }
1416     else
1417       {
1418 	if (got_offset < 0x1000)
1419 	  {
1420 	    memcpy(pov, plt_entry_32_pic12, plt_entry_size);
1421 	    S390_relocate_functions<size>::rela12(pov + 2, got_offset);
1422 	  }
1423 	else if (got_offset < 0x8000)
1424 	  {
1425 	    memcpy(pov, plt_entry_32_pic16, plt_entry_size);
1426 	    S390_relocate_functions<size>::rela16(pov + 2, got_offset);
1427 	  }
1428 	else
1429 	  {
1430 	    memcpy(pov, plt_entry_32_pic, plt_entry_size);
1431 	    elfcpp::Swap<32, true>::writeval(pov + 24, got_offset);
1432 	  }
1433       }
1434     typename elfcpp::Elf_types<size>::Elf_Addr target = plt_address;
1435     if (plt_offset >= 0x10000)
1436       {
1437 	// Would overflow pcrela16dbl - aim at the farthest previous jump
1438 	// we can reach.
1439 	if (plt_offset > 0x10000)
1440 	  {
1441 	    // Use the full range of pcrel16dbl.
1442 	    target = plt_address + plt_offset - 0x10000 + 18;
1443 	  }
1444 	else
1445 	  {
1446 	    // if plt_offset is exactly 0x10000, the above would aim at 18th byte
1447 	    // of first_plt_entry, which doesn't have the jump back like the others.
1448 	    // Aim at the next entry instead.
1449 	    target = plt_address + plt_offset - 0xffe0 + 18;
1450 	  }
1451       }
1452     S390_relocate_functions<size>::pcrela16dbl(pov + 20, target, plt_address + plt_offset + 18);
1453   }
1454   elfcpp::Swap<32, true>::writeval(pov + 28, plt_rel_offset);
1455   if (size == 64)
1456     return 14;
1457   else
1458     return 12;
1459 }
1460 
1461 // The .eh_frame unwind information for the PLT.
1462 
1463 template<>
1464 const unsigned char
1465 Output_data_plt_s390<32>::plt_eh_frame_cie[plt_eh_frame_cie_size] =
1466 {
1467   1,				// CIE version.
1468   'z',				// Augmentation: augmentation size included.
1469   'R',				// Augmentation: FDE encoding included.
1470   '\0',				// End of augmentation string.
1471   1,				// Code alignment factor.
1472   0x7c,				// Data alignment factor.
1473   14,				// Return address column.
1474   1,				// Augmentation size.
1475   (elfcpp::DW_EH_PE_pcrel	// FDE encoding.
1476    | elfcpp::DW_EH_PE_sdata4),
1477   elfcpp::DW_CFA_def_cfa, 15, 0x60,	// DW_CFA_def_cfa: r15 ofs 0x60.
1478 };
1479 
1480 template<>
1481 const unsigned char
1482 Output_data_plt_s390<64>::plt_eh_frame_cie[plt_eh_frame_cie_size] =
1483 {
1484   1,				// CIE version.
1485   'z',				// Augmentation: augmentation size included.
1486   'R',				// Augmentation: FDE encoding included.
1487   '\0',				// End of augmentation string.
1488   1,				// Code alignment factor.
1489   0x78,				// Data alignment factor.
1490   14,				// Return address column.
1491   1,				// Augmentation size.
1492   (elfcpp::DW_EH_PE_pcrel	// FDE encoding.
1493    | elfcpp::DW_EH_PE_sdata4),
1494   elfcpp::DW_CFA_def_cfa, 15, 0xa0,	// DW_CFA_def_cfa: r15 ofs 0xa0.
1495 };
1496 
1497 template<int size>
1498 const unsigned char
1499 Output_data_plt_s390<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
1500 {
1501   0, 0, 0, 0,				// Replaced with offset to .plt.
1502   0, 0, 0, 0,				// Replaced with size of .plt.
1503   0,					// Augmentation size.
1504   elfcpp::DW_CFA_nop,
1505   elfcpp::DW_CFA_nop,
1506   elfcpp::DW_CFA_nop
1507 };
1508 
1509 // Write out the PLT.  This uses the hand-coded instructions above,
1510 // and adjusts them as needed.
1511 
1512 template<int size>
1513 void
do_write(Output_file * of)1514 Output_data_plt_s390<size>::do_write(Output_file* of)
1515 {
1516   const off_t offset = this->offset();
1517   const section_size_type oview_size =
1518     convert_to_section_size_type(this->data_size());
1519   unsigned char* const oview = of->get_output_view(offset, oview_size);
1520 
1521   const off_t got_file_offset = this->got_plt_->offset();
1522   gold_assert(parameters->incremental_update()
1523 	      || (got_file_offset + this->got_plt_->data_size()
1524 		  == this->got_irelative_->offset()));
1525   const section_size_type got_size =
1526     convert_to_section_size_type(this->got_plt_->data_size()
1527 				 + this->got_irelative_->data_size());
1528   unsigned char* const got_view = of->get_output_view(got_file_offset,
1529 						      got_size);
1530 
1531   unsigned char* pov = oview;
1532 
1533   // The base address of the .plt section.
1534   typename elfcpp::Elf_types<size>::Elf_Addr plt_address = this->address();
1535   // The base address of the PLT portion of the .got section,
1536   // which is where the GOT pointer will point, and where the
1537   // three reserved GOT entries are located.
1538   typename elfcpp::Elf_types<size>::Elf_Addr got_address
1539     = this->got_plt_->address();
1540 
1541   this->fill_first_plt_entry(pov, got_address, plt_address);
1542   pov += this->get_plt_entry_size();
1543 
1544   unsigned char* got_pov = got_view;
1545 
1546   const int rel_size = elfcpp::Elf_sizes<size>::rela_size;
1547 
1548   unsigned int plt_offset = this->get_plt_entry_size();
1549   unsigned int plt_rel_offset = 0;
1550   unsigned int got_offset = 3 * size / 8;
1551   const unsigned int count = this->count_ + this->irelative_count_;
1552   // The first three entries in the GOT are reserved, and are written
1553   // by Output_data_got_plt_s390::do_write.
1554   got_pov += 3 * size / 8;
1555 
1556   for (unsigned int plt_index = 0;
1557        plt_index < count;
1558        ++plt_index,
1559 	 pov += plt_entry_size,
1560 	 got_pov += size / 8,
1561 	 plt_offset += plt_entry_size,
1562 	 plt_rel_offset += rel_size,
1563 	 got_offset += size / 8)
1564     {
1565       // Set and adjust the PLT entry itself.
1566       unsigned int lazy_offset = this->fill_plt_entry(pov,
1567 						      got_address, plt_address,
1568 						      got_offset, plt_offset,
1569 						      plt_rel_offset);
1570 
1571       // Set the entry in the GOT.
1572       elfcpp::Swap<size, true>::writeval(got_pov,
1573 					plt_address + plt_offset + lazy_offset);
1574     }
1575 
1576   gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
1577   gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
1578 
1579   of->write_output_view(offset, oview_size, oview);
1580   of->write_output_view(got_file_offset, got_size, got_view);
1581 }
1582 
1583 // Get the GOT section, creating it if necessary.
1584 
1585 template<int size>
1586 Output_data_got<size, true>*
got_section(Symbol_table * symtab,Layout * layout)1587 Target_s390<size>::got_section(Symbol_table* symtab, Layout* layout)
1588 {
1589   if (this->got_ == NULL)
1590     {
1591       gold_assert(symtab != NULL && layout != NULL);
1592 
1593       // When using -z now, we can treat .got as a relro section.
1594       // Without -z now, it is modified after program startup by lazy
1595       // PLT relocations.
1596       bool is_got_relro = parameters->options().now();
1597       Output_section_order got_order = (is_got_relro
1598 					? ORDER_RELRO_LAST
1599 					: ORDER_DATA);
1600 
1601       // The old GNU linker creates a .got.plt section.  We just
1602       // create another set of data in the .got section.  Note that we
1603       // always create a PLT if we create a GOT, although the PLT
1604       // might be empty.
1605       this->got_plt_ = new Output_data_got_plt_s390<size>(layout);
1606       layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1607 				      (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE),
1608 				      this->got_plt_, got_order, is_got_relro);
1609 
1610       // The first three entries are reserved.
1611       this->got_plt_->set_current_data_size(3 * size / 8);
1612 
1613       // If there are any IRELATIVE relocations, they get GOT entries
1614       // in .got.plt after the jump slot entries.
1615       this->got_irelative_ = new Output_data_space(size / 8, "** GOT IRELATIVE PLT");
1616       layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1617 				      (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE),
1618 				      this->got_irelative_,
1619 				      got_order, is_got_relro);
1620 
1621       // Unlike some targets (.e.g x86), S/390 does not use separate .got and
1622       // .got.plt sections in output.  The output .got section contains both
1623       // PLT and non-PLT GOT entries.
1624       this->got_ = new Output_data_got<size, true>();
1625 
1626       layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1627 				      (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE),
1628 				      this->got_, got_order, is_got_relro);
1629 
1630       // Define _GLOBAL_OFFSET_TABLE_ at the start of the GOT.
1631       this->global_offset_table_ =
1632         symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
1633 				      Symbol_table::PREDEFINED,
1634 				      this->got_plt_,
1635 				      0, 0, elfcpp::STT_OBJECT,
1636 				      elfcpp::STB_LOCAL,
1637 				      elfcpp::STV_HIDDEN, 0,
1638 				      false, false);
1639 
1640     }
1641   return this->got_;
1642 }
1643 
1644 // Get the dynamic reloc section, creating it if necessary.
1645 
1646 template<int size>
1647 typename Target_s390<size>::Reloc_section*
rela_dyn_section(Layout * layout)1648 Target_s390<size>::rela_dyn_section(Layout* layout)
1649 {
1650   if (this->rela_dyn_ == NULL)
1651     {
1652       gold_assert(layout != NULL);
1653       this->rela_dyn_ = new Reloc_section(parameters->options().combreloc());
1654       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
1655 				      elfcpp::SHF_ALLOC, this->rela_dyn_,
1656 				      ORDER_DYNAMIC_RELOCS, false);
1657     }
1658   return this->rela_dyn_;
1659 }
1660 
1661 // Get the section to use for IRELATIVE relocs, creating it if
1662 // necessary.  These go in .rela.dyn, but only after all other dynamic
1663 // relocations.  They need to follow the other dynamic relocations so
1664 // that they can refer to global variables initialized by those
1665 // relocs.
1666 
1667 template<int size>
1668 typename Target_s390<size>::Reloc_section*
rela_irelative_section(Layout * layout)1669 Target_s390<size>::rela_irelative_section(Layout* layout)
1670 {
1671   if (this->rela_irelative_ == NULL)
1672     {
1673       // Make sure we have already created the dynamic reloc section.
1674       this->rela_dyn_section(layout);
1675       this->rela_irelative_ = new Reloc_section(false);
1676       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
1677 				      elfcpp::SHF_ALLOC, this->rela_irelative_,
1678 				      ORDER_DYNAMIC_RELOCS, false);
1679       gold_assert(this->rela_dyn_->output_section()
1680 		  == this->rela_irelative_->output_section());
1681     }
1682   return this->rela_irelative_;
1683 }
1684 
1685 // Write the first three reserved words of the .got.plt section.
1686 // The remainder of the section is written while writing the PLT
1687 // in Output_data_plt_s390::do_write.
1688 
1689 template<int size>
1690 void
do_write(Output_file * of)1691 Output_data_got_plt_s390<size>::do_write(Output_file* of)
1692 {
1693   // The first entry in the GOT is the address of the .dynamic section
1694   // aka the PT_DYNAMIC segment.  The next two entries are reserved.
1695   // We saved space for them when we created the section in
1696   // Target_x86_64::got_section.
1697   const off_t got_file_offset = this->offset();
1698   gold_assert(this->data_size() >= 3 * size / 8);
1699   unsigned char* const got_view =
1700       of->get_output_view(got_file_offset, 3 * size / 8);
1701   Output_section* dynamic = this->layout_->dynamic_section();
1702   uint64_t dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
1703   elfcpp::Swap<size, true>::writeval(got_view, dynamic_addr);
1704   memset(got_view + size / 8, 0, 2 * size / 8);
1705   of->write_output_view(got_file_offset, 3 * size / 8, got_view);
1706 }
1707 
1708 // Create the PLT section.
1709 
1710 template<int size>
1711 void
make_plt_section(Symbol_table * symtab,Layout * layout)1712 Target_s390<size>::make_plt_section(Symbol_table* symtab, Layout* layout)
1713 {
1714   if (this->plt_ == NULL)
1715     {
1716       // Create the GOT sections first.
1717       this->got_section(symtab, layout);
1718 
1719       // Ensure that .rela.dyn always appears before .rela.plt  This is
1720       // necessary due to how, on 32-bit S/390 and some other targets,
1721       // .rela.dyn needs to include .rela.plt in it's range.
1722       this->rela_dyn_section(layout);
1723 
1724       this->plt_ = new Output_data_plt_s390<size>(layout,
1725 		      this->got_, this->got_plt_, this->got_irelative_);
1726 
1727       // Add unwind information if requested.
1728       if (parameters->options().ld_generated_unwind_info())
1729 	this->plt_->add_eh_frame(layout);
1730 
1731       layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1732 				      (elfcpp::SHF_ALLOC
1733 				       | elfcpp::SHF_EXECINSTR),
1734 				      this->plt_, ORDER_PLT, false);
1735 
1736       // Make the sh_info field of .rela.plt point to .plt.
1737       Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
1738       rela_plt_os->set_info_section(this->plt_->output_section());
1739     }
1740 }
1741 
1742 // Create a PLT entry for a global symbol.
1743 
1744 template<int size>
1745 void
make_plt_entry(Symbol_table * symtab,Layout * layout,Symbol * gsym)1746 Target_s390<size>::make_plt_entry(Symbol_table* symtab, Layout* layout,
1747 				    Symbol* gsym)
1748 {
1749   if (gsym->has_plt_offset())
1750     return;
1751 
1752   if (this->plt_ == NULL)
1753     this->make_plt_section(symtab, layout);
1754 
1755   this->plt_->add_entry(symtab, layout, gsym);
1756 }
1757 
1758 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1759 
1760 template<int size>
1761 void
make_local_ifunc_plt_entry(Symbol_table * symtab,Layout * layout,Sized_relobj_file<size,true> * relobj,unsigned int local_sym_index)1762 Target_s390<size>::make_local_ifunc_plt_entry(
1763     Symbol_table* symtab, Layout* layout,
1764     Sized_relobj_file<size, true>* relobj,
1765     unsigned int local_sym_index)
1766 {
1767   if (relobj->local_has_plt_offset(local_sym_index))
1768     return;
1769   if (this->plt_ == NULL)
1770     this->make_plt_section(symtab, layout);
1771   unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
1772 							      relobj,
1773 							      local_sym_index);
1774   relobj->set_local_plt_offset(local_sym_index, plt_offset);
1775 }
1776 
1777 // Return the number of entries in the PLT.
1778 
1779 template<int size>
1780 unsigned int
plt_entry_count() const1781 Target_s390<size>::plt_entry_count() const
1782 {
1783   if (this->plt_ == NULL)
1784     return 0;
1785   return this->plt_->entry_count();
1786 }
1787 
1788 // Return the offset of the first non-reserved PLT entry.
1789 
1790 template<int size>
1791 unsigned int
first_plt_entry_offset() const1792 Target_s390<size>::first_plt_entry_offset() const
1793 {
1794   return this->plt_->first_plt_entry_offset();
1795 }
1796 
1797 // Return the size of each PLT entry.
1798 
1799 template<int size>
1800 unsigned int
plt_entry_size() const1801 Target_s390<size>::plt_entry_size() const
1802 {
1803   return this->plt_->get_plt_entry_size();
1804 }
1805 
1806 // Create the GOT and PLT sections for an incremental update.
1807 
1808 template<int size>
1809 Output_data_got_base*
init_got_plt_for_update(Symbol_table * symtab,Layout * layout,unsigned int got_count,unsigned int plt_count)1810 Target_s390<size>::init_got_plt_for_update(Symbol_table* symtab,
1811 				       Layout* layout,
1812 				       unsigned int got_count,
1813 				       unsigned int plt_count)
1814 {
1815   gold_assert(this->got_ == NULL);
1816 
1817   // Add the three reserved entries.
1818   this->got_plt_ = new Output_data_got_plt_s390<size>(layout, (plt_count + 3) * size / 8);
1819   layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1820 				  (elfcpp::SHF_ALLOC
1821 				   | elfcpp::SHF_WRITE),
1822 				  this->got_plt_, ORDER_NON_RELRO_FIRST,
1823 				  false);
1824 
1825   // If there are any IRELATIVE relocations, they get GOT entries in
1826   // .got.plt after the jump slot entries.
1827   this->got_irelative_ = new Output_data_space(0, size / 8, "** GOT IRELATIVE PLT");
1828   layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1829 				  elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
1830 				  this->got_irelative_,
1831 				  ORDER_NON_RELRO_FIRST, false);
1832 
1833   this->got_ = new Output_data_got<size, true>(got_count * size / 8);
1834   layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1835 				  (elfcpp::SHF_ALLOC
1836 				   | elfcpp::SHF_WRITE),
1837 				  this->got_, ORDER_RELRO_LAST,
1838 				  true);
1839 
1840   // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1841   this->global_offset_table_ =
1842     symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
1843 				  Symbol_table::PREDEFINED,
1844 				  this->got_plt_,
1845 				  0, 0, elfcpp::STT_OBJECT,
1846 				  elfcpp::STB_LOCAL,
1847 				  elfcpp::STV_HIDDEN, 0,
1848 				  false, false);
1849 
1850   // Create the PLT section.
1851   this->plt_ = new Output_data_plt_s390<size>(layout,
1852 		  this->got_, this->got_plt_, this->got_irelative_, plt_count);
1853 
1854   // Add unwind information if requested.
1855   if (parameters->options().ld_generated_unwind_info())
1856     this->plt_->add_eh_frame(layout);
1857 
1858   layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1859 				  elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR,
1860 				  this->plt_, ORDER_PLT, false);
1861 
1862   // Make the sh_info field of .rela.plt point to .plt.
1863   Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
1864   rela_plt_os->set_info_section(this->plt_->output_section());
1865 
1866   // Create the rela_dyn section.
1867   this->rela_dyn_section(layout);
1868 
1869   return this->got_;
1870 }
1871 
1872 // Reserve a GOT entry for a local symbol, and regenerate any
1873 // necessary dynamic relocations.
1874 
1875 template<int size>
1876 void
reserve_local_got_entry(unsigned int got_index,Sized_relobj<size,true> * obj,unsigned int r_sym,unsigned int got_type)1877 Target_s390<size>::reserve_local_got_entry(
1878     unsigned int got_index,
1879     Sized_relobj<size, true>* obj,
1880     unsigned int r_sym,
1881     unsigned int got_type)
1882 {
1883   unsigned int got_offset = got_index * size / 8;
1884   Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
1885 
1886   this->got_->reserve_local(got_index, obj, r_sym, got_type);
1887   switch (got_type)
1888     {
1889     case GOT_TYPE_STANDARD:
1890       if (parameters->options().output_is_position_independent())
1891 	rela_dyn->add_local_relative(obj, r_sym, elfcpp::R_390_RELATIVE,
1892 				     this->got_, got_offset, 0, false);
1893       break;
1894     case GOT_TYPE_TLS_OFFSET:
1895       rela_dyn->add_local(obj, r_sym, elfcpp::R_390_TLS_TPOFF,
1896 			  this->got_, got_offset, 0);
1897       break;
1898     case GOT_TYPE_TLS_PAIR:
1899       this->got_->reserve_slot(got_index + 1);
1900       rela_dyn->add_local(obj, r_sym, elfcpp::R_390_TLS_DTPMOD,
1901 			  this->got_, got_offset, 0);
1902       break;
1903     default:
1904       gold_unreachable();
1905     }
1906 }
1907 
1908 // Reserve a GOT entry for a global symbol, and regenerate any
1909 // necessary dynamic relocations.
1910 
1911 template<int size>
1912 void
reserve_global_got_entry(unsigned int got_index,Symbol * gsym,unsigned int got_type)1913 Target_s390<size>::reserve_global_got_entry(unsigned int got_index,
1914 					      Symbol* gsym,
1915 					      unsigned int got_type)
1916 {
1917   unsigned int got_offset = got_index * size / 8;
1918   Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
1919 
1920   this->got_->reserve_global(got_index, gsym, got_type);
1921   switch (got_type)
1922     {
1923     case GOT_TYPE_STANDARD:
1924       if (!gsym->final_value_is_known())
1925 	{
1926 	  if (gsym->is_from_dynobj()
1927 	      || gsym->is_undefined()
1928 	      || gsym->is_preemptible()
1929 	      || gsym->type() == elfcpp::STT_GNU_IFUNC)
1930 	    rela_dyn->add_global(gsym, elfcpp::R_390_GLOB_DAT,
1931 				 this->got_, got_offset, 0);
1932 	  else
1933 	    rela_dyn->add_global_relative(gsym, elfcpp::R_390_RELATIVE,
1934 					  this->got_, got_offset, 0, false);
1935 	}
1936       break;
1937     case GOT_TYPE_TLS_OFFSET:
1938       rela_dyn->add_global_relative(gsym, elfcpp::R_390_TLS_TPOFF,
1939 				    this->got_, got_offset, 0, false);
1940       break;
1941     case GOT_TYPE_TLS_PAIR:
1942       this->got_->reserve_slot(got_index + 1);
1943       rela_dyn->add_global_relative(gsym, elfcpp::R_390_TLS_DTPMOD,
1944 				    this->got_, got_offset, 0, false);
1945       rela_dyn->add_global_relative(gsym, elfcpp::R_390_TLS_DTPOFF,
1946 				    this->got_, got_offset + size / 8, 0, false);
1947       break;
1948     default:
1949       gold_unreachable();
1950     }
1951 }
1952 
1953 // Register an existing PLT entry for a global symbol.
1954 
1955 template<int size>
1956 void
register_global_plt_entry(Symbol_table * symtab,Layout * layout,unsigned int plt_index,Symbol * gsym)1957 Target_s390<size>::register_global_plt_entry(Symbol_table* symtab,
1958 					       Layout* layout,
1959 					       unsigned int plt_index,
1960 					       Symbol* gsym)
1961 {
1962   gold_assert(this->plt_ != NULL);
1963   gold_assert(!gsym->has_plt_offset());
1964 
1965   this->plt_->reserve_slot(plt_index);
1966 
1967   gsym->set_plt_offset((plt_index + 1) * this->plt_entry_size());
1968 
1969   unsigned int got_offset = (plt_index + 3) * size / 8;
1970   this->plt_->add_relocation(symtab, layout, gsym, got_offset);
1971 }
1972 
1973 // Force a COPY relocation for a given symbol.
1974 
1975 template<int size>
1976 void
emit_copy_reloc(Symbol_table * symtab,Symbol * sym,Output_section * os,off_t offset)1977 Target_s390<size>::emit_copy_reloc(
1978     Symbol_table* symtab, Symbol* sym, Output_section* os, off_t offset)
1979 {
1980   this->copy_relocs_.emit_copy_reloc(symtab,
1981 				     symtab->get_sized_symbol<size>(sym),
1982 				     os,
1983 				     offset,
1984 				     this->rela_dyn_section(NULL));
1985 }
1986 
1987 // Create a GOT entry for the TLS module index.
1988 
1989 template<int size>
1990 unsigned int
got_mod_index_entry(Symbol_table * symtab,Layout * layout,Sized_relobj_file<size,true> * object)1991 Target_s390<size>::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
1992 					 Sized_relobj_file<size, true>* object)
1993 {
1994   if (this->got_mod_index_offset_ == -1U)
1995     {
1996       gold_assert(symtab != NULL && layout != NULL && object != NULL);
1997       Reloc_section* rela_dyn = this->rela_dyn_section(layout);
1998       Output_data_got<size, true>* got = this->got_section(symtab, layout);
1999       unsigned int got_offset = got->add_constant(0);
2000       rela_dyn->add_local(object, 0, elfcpp::R_390_TLS_DTPMOD, got,
2001 			  got_offset, 0);
2002       got->add_constant(0);
2003       this->got_mod_index_offset_ = got_offset;
2004     }
2005   return this->got_mod_index_offset_;
2006 }
2007 
2008 // Optimize the TLS relocation type based on what we know about the
2009 // symbol.  IS_FINAL is true if the final address of this symbol is
2010 // known at link time.
2011 
2012 template<int size>
2013 tls::Tls_optimization
optimize_tls_reloc(bool is_final,int r_type)2014 Target_s390<size>::optimize_tls_reloc(bool is_final, int r_type)
2015 {
2016   // If we are generating a shared library, then we can't do anything
2017   // in the linker.
2018   if (parameters->options().shared())
2019     return tls::TLSOPT_NONE;
2020 
2021   switch (r_type)
2022     {
2023     case elfcpp::R_390_TLS_GD32:
2024     case elfcpp::R_390_TLS_GD64:
2025     case elfcpp::R_390_TLS_GDCALL:
2026       // These are General-Dynamic which permits fully general TLS
2027       // access.  Since we know that we are generating an executable,
2028       // we can convert this to Initial-Exec.  If we also know that
2029       // this is a local symbol, we can further switch to Local-Exec.
2030       if (is_final)
2031 	return tls::TLSOPT_TO_LE;
2032       return tls::TLSOPT_TO_IE;
2033 
2034     case elfcpp::R_390_TLS_LDM32:
2035     case elfcpp::R_390_TLS_LDM64:
2036     case elfcpp::R_390_TLS_LDO32:
2037     case elfcpp::R_390_TLS_LDO64:
2038     case elfcpp::R_390_TLS_LDCALL:
2039       // This is Local-Dynamic, which refers to a local symbol in the
2040       // dynamic TLS block.  Since we know that we generating an
2041       // executable, we can switch to Local-Exec.
2042       return tls::TLSOPT_TO_LE;
2043 
2044     case elfcpp::R_390_TLS_IE32:
2045     case elfcpp::R_390_TLS_IE64:
2046     case elfcpp::R_390_TLS_GOTIE32:
2047     case elfcpp::R_390_TLS_GOTIE64:
2048     case elfcpp::R_390_TLS_LOAD:
2049       // These are Initial-Exec relocs which get the thread offset
2050       // from the GOT.  If we know that we are linking against the
2051       // local symbol, we can switch to Local-Exec, which links the
2052       // thread offset into the instruction.
2053       if (is_final)
2054 	return tls::TLSOPT_TO_LE;
2055       return tls::TLSOPT_NONE;
2056 
2057     case elfcpp::R_390_TLS_GOTIE12:
2058     case elfcpp::R_390_TLS_IEENT:
2059     case elfcpp::R_390_TLS_GOTIE20:
2060       // These are Initial-Exec, but cannot be optimized.
2061       return tls::TLSOPT_NONE;
2062 
2063     case elfcpp::R_390_TLS_LE32:
2064     case elfcpp::R_390_TLS_LE64:
2065       // When we already have Local-Exec, there is nothing further we
2066       // can do.
2067       return tls::TLSOPT_NONE;
2068 
2069     default:
2070       gold_unreachable();
2071     }
2072 }
2073 
2074 // Get the Reference_flags for a particular relocation.
2075 
2076 template<int size>
2077 int
get_reference_flags(unsigned int r_type)2078 Target_s390<size>::Scan::get_reference_flags(unsigned int r_type)
2079 {
2080   switch (r_type)
2081     {
2082     case elfcpp::R_390_NONE:
2083     case elfcpp::R_390_GNU_VTINHERIT:
2084     case elfcpp::R_390_GNU_VTENTRY:
2085     case elfcpp::R_390_GOTPC:
2086     case elfcpp::R_390_GOTPCDBL:
2087       // No symbol reference.
2088       return 0;
2089 
2090     case elfcpp::R_390_64:
2091     case elfcpp::R_390_32:
2092     case elfcpp::R_390_20:
2093     case elfcpp::R_390_16:
2094     case elfcpp::R_390_12:
2095     case elfcpp::R_390_8:
2096       return Symbol::ABSOLUTE_REF;
2097 
2098     case elfcpp::R_390_PC12DBL:
2099     case elfcpp::R_390_PC16:
2100     case elfcpp::R_390_PC16DBL:
2101     case elfcpp::R_390_PC24DBL:
2102     case elfcpp::R_390_PC32:
2103     case elfcpp::R_390_PC32DBL:
2104     case elfcpp::R_390_PC64:
2105     case elfcpp::R_390_GOTOFF16:
2106     case elfcpp::R_390_GOTOFF32:
2107     case elfcpp::R_390_GOTOFF64:
2108       return Symbol::RELATIVE_REF;
2109 
2110     case elfcpp::R_390_PLT12DBL:
2111     case elfcpp::R_390_PLT16DBL:
2112     case elfcpp::R_390_PLT24DBL:
2113     case elfcpp::R_390_PLT32:
2114     case elfcpp::R_390_PLT32DBL:
2115     case elfcpp::R_390_PLT64:
2116     case elfcpp::R_390_PLTOFF16:
2117     case elfcpp::R_390_PLTOFF32:
2118     case elfcpp::R_390_PLTOFF64:
2119       return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
2120 
2121     case elfcpp::R_390_GOT12:
2122     case elfcpp::R_390_GOT16:
2123     case elfcpp::R_390_GOT20:
2124     case elfcpp::R_390_GOT32:
2125     case elfcpp::R_390_GOT64:
2126     case elfcpp::R_390_GOTENT:
2127     case elfcpp::R_390_GOTPLT12:
2128     case elfcpp::R_390_GOTPLT16:
2129     case elfcpp::R_390_GOTPLT20:
2130     case elfcpp::R_390_GOTPLT32:
2131     case elfcpp::R_390_GOTPLT64:
2132     case elfcpp::R_390_GOTPLTENT:
2133       // Absolute in GOT.
2134       return Symbol::ABSOLUTE_REF;
2135 
2136     case elfcpp::R_390_TLS_GD32:          // Global-dynamic
2137     case elfcpp::R_390_TLS_GD64:
2138     case elfcpp::R_390_TLS_GDCALL:
2139     case elfcpp::R_390_TLS_LDM32:         // Local-dynamic
2140     case elfcpp::R_390_TLS_LDM64:
2141     case elfcpp::R_390_TLS_LDO32:
2142     case elfcpp::R_390_TLS_LDO64:
2143     case elfcpp::R_390_TLS_LDCALL:
2144     case elfcpp::R_390_TLS_IE32:          // Initial-exec
2145     case elfcpp::R_390_TLS_IE64:
2146     case elfcpp::R_390_TLS_IEENT:
2147     case elfcpp::R_390_TLS_GOTIE12:
2148     case elfcpp::R_390_TLS_GOTIE20:
2149     case elfcpp::R_390_TLS_GOTIE32:
2150     case elfcpp::R_390_TLS_GOTIE64:
2151     case elfcpp::R_390_TLS_LOAD:
2152     case elfcpp::R_390_TLS_LE32:          // Local-exec
2153     case elfcpp::R_390_TLS_LE64:
2154       return Symbol::TLS_REF;
2155 
2156     case elfcpp::R_390_COPY:
2157     case elfcpp::R_390_GLOB_DAT:
2158     case elfcpp::R_390_JMP_SLOT:
2159     case elfcpp::R_390_RELATIVE:
2160     case elfcpp::R_390_IRELATIVE:
2161     case elfcpp::R_390_TLS_TPOFF:
2162     case elfcpp::R_390_TLS_DTPOFF:
2163     case elfcpp::R_390_TLS_DTPMOD:
2164     default:
2165       // Not expected.  We will give an error later.
2166       return 0;
2167     }
2168 }
2169 
2170 // Report an unsupported relocation against a local symbol.
2171 
2172 template<int size>
2173 void
unsupported_reloc_local(Sized_relobj_file<size,true> * object,unsigned int r_type)2174 Target_s390<size>::Scan::unsupported_reloc_local(
2175      Sized_relobj_file<size, true>* object,
2176      unsigned int r_type)
2177 {
2178   gold_error(_("%s: unsupported reloc %u against local symbol"),
2179 	     object->name().c_str(), r_type);
2180 }
2181 
2182 // We are about to emit a dynamic relocation of type R_TYPE.  If the
2183 // dynamic linker does not support it, issue an error.
2184 
2185 template<int size>
2186 void
check_non_pic(Relobj * object,unsigned int r_type)2187 Target_s390<size>::Scan::check_non_pic(Relobj* object, unsigned int r_type)
2188 {
2189   gold_assert(r_type != elfcpp::R_390_NONE);
2190 
2191   if (size == 64)
2192     {
2193       switch (r_type)
2194 	{
2195 	  // These are the relocation types supported by glibc for s390 64-bit.
2196 	case elfcpp::R_390_RELATIVE:
2197 	case elfcpp::R_390_IRELATIVE:
2198 	case elfcpp::R_390_COPY:
2199 	case elfcpp::R_390_GLOB_DAT:
2200 	case elfcpp::R_390_JMP_SLOT:
2201 	case elfcpp::R_390_TLS_DTPMOD:
2202 	case elfcpp::R_390_TLS_DTPOFF:
2203 	case elfcpp::R_390_TLS_TPOFF:
2204 	case elfcpp::R_390_8:
2205 	case elfcpp::R_390_16:
2206 	case elfcpp::R_390_32:
2207 	case elfcpp::R_390_64:
2208 	case elfcpp::R_390_PC16:
2209 	case elfcpp::R_390_PC16DBL:
2210 	case elfcpp::R_390_PC32:
2211 	case elfcpp::R_390_PC32DBL:
2212 	case elfcpp::R_390_PC64:
2213 	  return;
2214 
2215 	default:
2216 	  break;
2217 	}
2218     }
2219   else
2220     {
2221       switch (r_type)
2222 	{
2223 	  // These are the relocation types supported by glibc for s390 32-bit.
2224 	case elfcpp::R_390_RELATIVE:
2225 	case elfcpp::R_390_IRELATIVE:
2226 	case elfcpp::R_390_COPY:
2227 	case elfcpp::R_390_GLOB_DAT:
2228 	case elfcpp::R_390_JMP_SLOT:
2229 	case elfcpp::R_390_TLS_DTPMOD:
2230 	case elfcpp::R_390_TLS_DTPOFF:
2231 	case elfcpp::R_390_TLS_TPOFF:
2232 	case elfcpp::R_390_8:
2233 	case elfcpp::R_390_16:
2234 	case elfcpp::R_390_32:
2235 	case elfcpp::R_390_PC16:
2236 	case elfcpp::R_390_PC16DBL:
2237 	case elfcpp::R_390_PC32:
2238 	case elfcpp::R_390_PC32DBL:
2239 	  return;
2240 
2241 	default:
2242 	  break;
2243 	}
2244     }
2245 
2246   // This prevents us from issuing more than one error per reloc
2247   // section.  But we can still wind up issuing more than one
2248   // error per object file.
2249   if (this->issued_non_pic_error_)
2250     return;
2251   gold_assert(parameters->options().output_is_position_independent());
2252   object->error(_("requires unsupported dynamic reloc; "
2253 		  "recompile with -fPIC"));
2254   this->issued_non_pic_error_ = true;
2255   return;
2256 }
2257 
2258 // Return whether we need to make a PLT entry for a relocation of the
2259 // given type against a STT_GNU_IFUNC symbol.
2260 
2261 template<int size>
2262 bool
reloc_needs_plt_for_ifunc(Sized_relobj_file<size,true> * object,unsigned int r_type)2263 Target_s390<size>::Scan::reloc_needs_plt_for_ifunc(
2264      Sized_relobj_file<size, true>* object,
2265      unsigned int r_type)
2266 {
2267   int flags = Scan::get_reference_flags(r_type);
2268   if (flags & Symbol::TLS_REF)
2269     gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
2270 	       object->name().c_str(), r_type);
2271   return flags != 0;
2272 }
2273 
2274 // Scan a relocation for a local symbol.
2275 
2276 template<int size>
2277 inline void
local(Symbol_table * symtab,Layout * layout,Target_s390<size> * target,Sized_relobj_file<size,true> * object,unsigned int data_shndx,Output_section * output_section,const elfcpp::Rela<size,true> & reloc,unsigned int r_type,const elfcpp::Sym<size,true> & lsym,bool is_discarded)2278 Target_s390<size>::Scan::local(Symbol_table* symtab,
2279 				 Layout* layout,
2280 				 Target_s390<size>* target,
2281 				 Sized_relobj_file<size, true>* object,
2282 				 unsigned int data_shndx,
2283 				 Output_section* output_section,
2284 				 const elfcpp::Rela<size, true>& reloc,
2285 				 unsigned int r_type,
2286 				 const elfcpp::Sym<size, true>& lsym,
2287 				 bool is_discarded)
2288 {
2289   if (is_discarded)
2290     return;
2291 
2292   // A local STT_GNU_IFUNC symbol may require a PLT entry.
2293   bool is_ifunc = lsym.get_st_type() == elfcpp::STT_GNU_IFUNC;
2294 
2295   if (is_ifunc && this->reloc_needs_plt_for_ifunc(object, r_type))
2296     {
2297       unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2298       target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
2299     }
2300 
2301   switch (r_type)
2302     {
2303     case elfcpp::R_390_NONE:
2304     case elfcpp::R_390_GNU_VTINHERIT:
2305     case elfcpp::R_390_GNU_VTENTRY:
2306       break;
2307 
2308     case elfcpp::R_390_64:
2309       // If building a shared library (or a position-independent
2310       // executable), we need to create a dynamic relocation for this
2311       // location.  The relocation applied at link time will apply the
2312       // link-time value, so we flag the location with an
2313       // R_390_RELATIVE relocation so the dynamic loader can
2314       // relocate it easily.
2315       if (parameters->options().output_is_position_independent() && size == 64)
2316 	{
2317 	  unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2318 	  Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2319 	  rela_dyn->add_local_relative(object, r_sym,
2320 				       elfcpp::R_390_RELATIVE,
2321 				       output_section, data_shndx,
2322 				       reloc.get_r_offset(),
2323 				       reloc.get_r_addend(), is_ifunc);
2324 	}
2325       break;
2326 
2327     case elfcpp::R_390_32:
2328     case elfcpp::R_390_20:
2329     case elfcpp::R_390_16:
2330     case elfcpp::R_390_12:
2331     case elfcpp::R_390_8:
2332       if (parameters->options().output_is_position_independent())
2333 	{
2334 	  if (size == 32 && r_type == elfcpp::R_390_32)
2335 	    {
2336 	      unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2337 	      Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2338 	      rela_dyn->add_local_relative(object, r_sym,
2339 					   elfcpp::R_390_RELATIVE,
2340 					   output_section, data_shndx,
2341 					   reloc.get_r_offset(),
2342 					   reloc.get_r_addend(), is_ifunc);
2343 	      break;
2344 	    }
2345 
2346 	  check_non_pic(object, r_type);
2347 
2348 	  Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2349 	  unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2350 	  if (lsym.get_st_type() != elfcpp::STT_SECTION)
2351 	    rela_dyn->add_local(object, r_sym, r_type, output_section,
2352 				data_shndx, reloc.get_r_offset(),
2353 				reloc.get_r_addend());
2354 	  else
2355 	    {
2356 	      gold_assert(lsym.get_st_value() == 0);
2357 	      unsigned int shndx = lsym.get_st_shndx();
2358 	      bool is_ordinary;
2359 	      shndx = object->adjust_sym_shndx(r_sym, shndx,
2360 					       &is_ordinary);
2361 	      if (!is_ordinary)
2362 		object->error(_("section symbol %u has bad shndx %u"),
2363 			      r_sym, shndx);
2364 	      else
2365 		rela_dyn->add_local_section(object, shndx,
2366 					    r_type, output_section,
2367 					    data_shndx, reloc.get_r_offset(),
2368 					    reloc.get_r_addend());
2369 	    }
2370 	}
2371       break;
2372 
2373     case elfcpp::R_390_PC12DBL:
2374     case elfcpp::R_390_PC16:
2375     case elfcpp::R_390_PC16DBL:
2376     case elfcpp::R_390_PC24DBL:
2377     case elfcpp::R_390_PC32:
2378     case elfcpp::R_390_PC32DBL:
2379     case elfcpp::R_390_PC64:
2380       break;
2381 
2382     case elfcpp::R_390_PLT12DBL:
2383     case elfcpp::R_390_PLT16DBL:
2384     case elfcpp::R_390_PLT24DBL:
2385     case elfcpp::R_390_PLT32:
2386     case elfcpp::R_390_PLT32DBL:
2387     case elfcpp::R_390_PLT64:
2388       // Since we know this is a local symbol, we can handle this as a
2389       // PC32 reloc.
2390       break;
2391 
2392     case elfcpp::R_390_GOTPC:
2393     case elfcpp::R_390_GOTPCDBL:
2394     case elfcpp::R_390_GOTOFF16:
2395     case elfcpp::R_390_GOTOFF32:
2396     case elfcpp::R_390_GOTOFF64:
2397     case elfcpp::R_390_PLTOFF16:
2398     case elfcpp::R_390_PLTOFF32:
2399     case elfcpp::R_390_PLTOFF64:
2400       // We need a GOT section.
2401       target->got_section(symtab, layout);
2402       // For PLTOFF*, we'd normally want a PLT section, but since we
2403       // know this is a local symbol, no PLT is needed.
2404       break;
2405 
2406     case elfcpp::R_390_GOT12:
2407     case elfcpp::R_390_GOT16:
2408     case elfcpp::R_390_GOT20:
2409     case elfcpp::R_390_GOT32:
2410     case elfcpp::R_390_GOT64:
2411     case elfcpp::R_390_GOTENT:
2412     case elfcpp::R_390_GOTPLT12:
2413     case elfcpp::R_390_GOTPLT16:
2414     case elfcpp::R_390_GOTPLT20:
2415     case elfcpp::R_390_GOTPLT32:
2416     case elfcpp::R_390_GOTPLT64:
2417     case elfcpp::R_390_GOTPLTENT:
2418       {
2419 	// The symbol requires a GOT section.
2420 	Output_data_got<size, true>* got = target->got_section(symtab, layout);
2421 
2422 	// The symbol requires a GOT entry.
2423 	unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2424 
2425 	// For a STT_GNU_IFUNC symbol we want the PLT offset.  That
2426 	// lets function pointers compare correctly with shared
2427 	// libraries.  Otherwise we would need an IRELATIVE reloc.
2428 	bool is_new;
2429 	if (is_ifunc)
2430 	  is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
2431 	else
2432 	  is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
2433 	if (is_new)
2434 	  {
2435 	    // If we are generating a shared object, we need to add a
2436 	    // dynamic relocation for this symbol's GOT entry.
2437 	    if (parameters->options().output_is_position_independent())
2438 	      {
2439 		Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2440 		unsigned int got_offset =
2441 		  object->local_got_offset(r_sym, GOT_TYPE_STANDARD);
2442 		rela_dyn->add_local_relative(object, r_sym,
2443 					     elfcpp::R_390_RELATIVE,
2444 					     got, got_offset, 0, is_ifunc);
2445 	      }
2446 	  }
2447 	// For GOTPLT*, we'd normally want a PLT section, but since
2448 	// we know this is a local symbol, no PLT is needed.
2449       }
2450       break;
2451 
2452     case elfcpp::R_390_COPY:
2453     case elfcpp::R_390_GLOB_DAT:
2454     case elfcpp::R_390_JMP_SLOT:
2455     case elfcpp::R_390_RELATIVE:
2456     case elfcpp::R_390_IRELATIVE:
2457       // These are outstanding tls relocs, which are unexpected when linking
2458     case elfcpp::R_390_TLS_TPOFF:
2459     case elfcpp::R_390_TLS_DTPOFF:
2460     case elfcpp::R_390_TLS_DTPMOD:
2461       gold_error(_("%s: unexpected reloc %u in object file"),
2462 		 object->name().c_str(), r_type);
2463       break;
2464 
2465       // These are initial tls relocs, which are expected when linking
2466     case elfcpp::R_390_TLS_GD32:          // Global-dynamic
2467     case elfcpp::R_390_TLS_GD64:
2468     case elfcpp::R_390_TLS_GDCALL:
2469     case elfcpp::R_390_TLS_LDM32:         // Local-dynamic
2470     case elfcpp::R_390_TLS_LDM64:
2471     case elfcpp::R_390_TLS_LDO32:
2472     case elfcpp::R_390_TLS_LDO64:
2473     case elfcpp::R_390_TLS_LDCALL:
2474     case elfcpp::R_390_TLS_IE32:          // Initial-exec
2475     case elfcpp::R_390_TLS_IE64:
2476     case elfcpp::R_390_TLS_IEENT:
2477     case elfcpp::R_390_TLS_GOTIE12:
2478     case elfcpp::R_390_TLS_GOTIE20:
2479     case elfcpp::R_390_TLS_GOTIE32:
2480     case elfcpp::R_390_TLS_GOTIE64:
2481     case elfcpp::R_390_TLS_LOAD:
2482     case elfcpp::R_390_TLS_LE32:          // Local-exec
2483     case elfcpp::R_390_TLS_LE64:
2484       {
2485 	bool output_is_shared = parameters->options().shared();
2486 	const tls::Tls_optimization optimized_type
2487 	    = Target_s390<size>::optimize_tls_reloc(!output_is_shared,
2488 						      r_type);
2489 	switch (r_type)
2490 	  {
2491 	  case elfcpp::R_390_TLS_GD32:       // General-dynamic
2492 	  case elfcpp::R_390_TLS_GD64:
2493 	  case elfcpp::R_390_TLS_GDCALL:
2494 	    if (optimized_type == tls::TLSOPT_NONE)
2495 	      {
2496 		// Create a pair of GOT entries for the module index and
2497 		// dtv-relative offset.
2498 		Output_data_got<size, true>* got
2499 		    = target->got_section(symtab, layout);
2500 		unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2501 		unsigned int shndx = lsym.get_st_shndx();
2502 		bool is_ordinary;
2503 		shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
2504 		if (!is_ordinary)
2505 		  object->error(_("local symbol %u has bad shndx %u"),
2506 			      r_sym, shndx);
2507 		else
2508 		  got->add_local_pair_with_rel(object, r_sym,
2509 					       shndx,
2510 					       GOT_TYPE_TLS_PAIR,
2511 					       target->rela_dyn_section(layout),
2512 					       elfcpp::R_390_TLS_DTPMOD);
2513 	      }
2514 	    else if (optimized_type != tls::TLSOPT_TO_LE)
2515 	      unsupported_reloc_local(object, r_type);
2516 	    break;
2517 
2518 	  case elfcpp::R_390_TLS_LDM32:       // Local-dynamic
2519 	  case elfcpp::R_390_TLS_LDM64:
2520 	  case elfcpp::R_390_TLS_LDCALL:
2521 	    if (optimized_type == tls::TLSOPT_NONE)
2522 	      {
2523 		// Create a GOT entry for the module index.
2524 		target->got_mod_index_entry(symtab, layout, object);
2525 	      }
2526 	    else if (optimized_type != tls::TLSOPT_TO_LE)
2527 	      unsupported_reloc_local(object, r_type);
2528 	    break;
2529 
2530 	  case elfcpp::R_390_TLS_LDO32:
2531 	  case elfcpp::R_390_TLS_LDO64:
2532 	    break;
2533 
2534 	  case elfcpp::R_390_TLS_IE32:    // Initial-exec
2535 	  case elfcpp::R_390_TLS_IE64:
2536 	    // These two involve an absolute address
2537 	    if (parameters->options().shared()
2538 		&& optimized_type == tls::TLSOPT_NONE)
2539 	      {
2540 		if ((size == 32 && r_type == elfcpp::R_390_TLS_IE32) ||
2541 		    (size == 64 && r_type == elfcpp::R_390_TLS_IE64))
2542 		  {
2543 		    // We need to create a dynamic relocation.
2544 		    Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2545 		    unsigned int r_sym =
2546 			elfcpp::elf_r_sym<size>(reloc.get_r_info());
2547 		    rela_dyn->add_local_relative(object, r_sym,
2548 						elfcpp::R_390_RELATIVE,
2549 						output_section, data_shndx,
2550 						reloc.get_r_offset(),
2551 						reloc.get_r_addend(), false);
2552 		  }
2553 		else
2554 		  {
2555 		    unsupported_reloc_local(object, r_type);
2556 		  }
2557 	      }
2558 	    // fall through
2559 	  case elfcpp::R_390_TLS_IEENT:
2560 	  case elfcpp::R_390_TLS_GOTIE12:
2561 	  case elfcpp::R_390_TLS_GOTIE20:
2562 	  case elfcpp::R_390_TLS_GOTIE32:
2563 	  case elfcpp::R_390_TLS_GOTIE64:
2564 	  case elfcpp::R_390_TLS_LOAD:
2565 	    layout->set_has_static_tls();
2566 	    if (optimized_type == tls::TLSOPT_NONE)
2567 	      {
2568 		if (!output_is_shared)
2569 		  {
2570 		    // We're making an executable, and the symbol is local, but
2571 		    // we cannot optimize to LE.  Make a const GOT entry instead.
2572 		    Output_data_got<size, true>* got
2573 			= target->got_section(symtab, layout);
2574 		    unsigned int r_sym
2575 			= elfcpp::elf_r_sym<size>(reloc.get_r_info());
2576 		    got->add_local_plt(object, r_sym, GOT_TYPE_TLS_OFFSET);
2577 		  }
2578 		else
2579 		{
2580 		  // Create a GOT entry for the tp-relative offset.
2581 		  Output_data_got<size, true>* got
2582 		      = target->got_section(symtab, layout);
2583 		  unsigned int r_sym
2584 		      = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2585 		  got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
2586 					  target->rela_dyn_section(layout),
2587 					  elfcpp::R_390_TLS_TPOFF);
2588 		}
2589 	      }
2590 	    else if (optimized_type != tls::TLSOPT_TO_LE)
2591 	      unsupported_reloc_local(object, r_type);
2592 	    break;
2593 
2594 	  case elfcpp::R_390_TLS_LE32:     // Local-exec
2595 	  case elfcpp::R_390_TLS_LE64:
2596 	    layout->set_has_static_tls();
2597 	    if (output_is_shared)
2598 	    {
2599 	      // We need to create a dynamic relocation.
2600 	      if ((size == 32 && r_type == elfcpp::R_390_TLS_LE32) ||
2601 	          (size == 64 && r_type == elfcpp::R_390_TLS_LE64))
2602 		{
2603 		  Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2604 		  unsigned int r_sym
2605 		      = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2606 		  gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
2607 		  rela_dyn->add_local(object, r_sym, elfcpp::R_390_TLS_TPOFF,
2608 				      output_section, data_shndx,
2609 				      reloc.get_r_offset(),
2610 				      reloc.get_r_addend());
2611 		}
2612 	      else
2613 		{
2614 		  unsupported_reloc_local(object, r_type);
2615 		}
2616 	    }
2617 	    break;
2618 
2619 	  default:
2620 	    gold_unreachable();
2621 	  }
2622       }
2623       break;
2624 
2625     default:
2626       gold_error(_("%s: unsupported reloc %u against local symbol"),
2627 		 object->name().c_str(), r_type);
2628       break;
2629     }
2630 }
2631 
2632 // Scan a relocation for a global symbol.
2633 
2634 template<int size>
2635 inline void
global(Symbol_table * symtab,Layout * layout,Target_s390<size> * target,Sized_relobj_file<size,true> * object,unsigned int data_shndx,Output_section * output_section,const elfcpp::Rela<size,true> & reloc,unsigned int r_type,Symbol * gsym)2636 Target_s390<size>::Scan::global(Symbol_table* symtab,
2637 			    Layout* layout,
2638 			    Target_s390<size>* target,
2639 			    Sized_relobj_file<size, true>* object,
2640 			    unsigned int data_shndx,
2641 			    Output_section* output_section,
2642 			    const elfcpp::Rela<size, true>& reloc,
2643 			    unsigned int r_type,
2644 			    Symbol* gsym)
2645 {
2646   // A STT_GNU_IFUNC symbol may require a PLT entry.
2647   if (gsym->type() == elfcpp::STT_GNU_IFUNC
2648       && this->reloc_needs_plt_for_ifunc(object, r_type))
2649     target->make_plt_entry(symtab, layout, gsym);
2650 
2651   switch (r_type)
2652     {
2653     case elfcpp::R_390_NONE:
2654     case elfcpp::R_390_GNU_VTINHERIT:
2655     case elfcpp::R_390_GNU_VTENTRY:
2656       break;
2657 
2658     case elfcpp::R_390_64:
2659     case elfcpp::R_390_32:
2660     case elfcpp::R_390_20:
2661     case elfcpp::R_390_16:
2662     case elfcpp::R_390_12:
2663     case elfcpp::R_390_8:
2664       {
2665 	// Make a PLT entry if necessary.
2666 	if (gsym->needs_plt_entry())
2667 	  {
2668 	    target->make_plt_entry(symtab, layout, gsym);
2669 	    // Since this is not a PC-relative relocation, we may be
2670 	    // taking the address of a function. In that case we need to
2671 	    // set the entry in the dynamic symbol table to the address of
2672 	    // the PLT entry.
2673 	    if (gsym->is_from_dynobj() && !parameters->options().shared())
2674 	      gsym->set_needs_dynsym_value();
2675 	  }
2676 	// Make a dynamic relocation if necessary.
2677 	if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2678 	  {
2679 	    if (!parameters->options().output_is_position_independent()
2680 		&& gsym->may_need_copy_reloc())
2681 	      {
2682 		target->copy_reloc(symtab, layout, object,
2683 				   data_shndx, output_section, gsym, reloc);
2684 	      }
2685 	    else if (((size == 64 && r_type == elfcpp::R_390_64)
2686 		      || (size == 32 && r_type == elfcpp::R_390_32))
2687 		     && gsym->type() == elfcpp::STT_GNU_IFUNC
2688 		     && gsym->can_use_relative_reloc(false)
2689 		     && !gsym->is_from_dynobj()
2690 		     && !gsym->is_undefined()
2691 		     && !gsym->is_preemptible())
2692 	      {
2693 		// Use an IRELATIVE reloc for a locally defined
2694 		// STT_GNU_IFUNC symbol.  This makes a function
2695 		// address in a PIE executable match the address in a
2696 		// shared library that it links against.
2697 		Reloc_section* rela_dyn =
2698 		  target->rela_irelative_section(layout);
2699 		unsigned int r_type = elfcpp::R_390_IRELATIVE;
2700 		rela_dyn->add_symbolless_global_addend(gsym, r_type,
2701 						       output_section, object,
2702 						       data_shndx,
2703 						       reloc.get_r_offset(),
2704 						       reloc.get_r_addend());
2705 	      }
2706 	    else if (((size == 64 && r_type == elfcpp::R_390_64)
2707 		      || (size == 32 && r_type == elfcpp::R_390_32))
2708 		     && gsym->can_use_relative_reloc(false))
2709 	      {
2710 		Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2711 		rela_dyn->add_global_relative(gsym, elfcpp::R_390_RELATIVE,
2712 					      output_section, object,
2713 					      data_shndx,
2714 					      reloc.get_r_offset(),
2715 					      reloc.get_r_addend(), false);
2716 	      }
2717 	    else
2718 	      {
2719 		check_non_pic(object, r_type);
2720 		Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2721 		rela_dyn->add_global(gsym, r_type, output_section, object,
2722 				     data_shndx, reloc.get_r_offset(),
2723 				     reloc.get_r_addend());
2724 	      }
2725 	  }
2726       }
2727       break;
2728 
2729     case elfcpp::R_390_PC12DBL:
2730     case elfcpp::R_390_PC16:
2731     case elfcpp::R_390_PC16DBL:
2732     case elfcpp::R_390_PC24DBL:
2733     case elfcpp::R_390_PC32:
2734     case elfcpp::R_390_PC32DBL:
2735     case elfcpp::R_390_PC64:
2736       {
2737 	// Make a PLT entry if necessary.
2738 	if (gsym->needs_plt_entry())
2739 	  {
2740 	    target->make_plt_entry(symtab, layout, gsym);
2741 	    // larl is often used to take address of a function.  Aim the
2742 	    // symbol at the PLT entry.
2743 	    if (gsym->is_from_dynobj() && !parameters->options().shared())
2744 	      gsym->set_needs_dynsym_value();
2745 	  }
2746 	// Make a dynamic relocation if necessary.
2747 	if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2748 	  {
2749 	    if (parameters->options().output_is_executable()
2750 		&& gsym->may_need_copy_reloc())
2751 	      {
2752 		target->copy_reloc(symtab, layout, object,
2753 				   data_shndx, output_section, gsym, reloc);
2754 	      }
2755 	    else
2756 	      {
2757 		check_non_pic(object, r_type);
2758 		Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2759 		rela_dyn->add_global(gsym, r_type, output_section, object,
2760 				     data_shndx, reloc.get_r_offset(),
2761 				     reloc.get_r_addend());
2762 	      }
2763 	  }
2764       }
2765       break;
2766 
2767     case elfcpp::R_390_PLT12DBL:
2768     case elfcpp::R_390_PLT16DBL:
2769     case elfcpp::R_390_PLT24DBL:
2770     case elfcpp::R_390_PLT32:
2771     case elfcpp::R_390_PLT32DBL:
2772     case elfcpp::R_390_PLT64:
2773       // If the symbol is fully resolved, this is just a PC32 reloc.
2774       // Otherwise we need a PLT entry.
2775       if (gsym->final_value_is_known())
2776 	break;
2777       // If building a shared library, we can also skip the PLT entry
2778       // if the symbol is defined in the output file and is protected
2779       // or hidden.
2780       if (gsym->is_defined()
2781 	  && !gsym->is_from_dynobj()
2782 	  && !gsym->is_preemptible())
2783 	break;
2784       target->make_plt_entry(symtab, layout, gsym);
2785       break;
2786 
2787     case elfcpp::R_390_GOTPC:
2788     case elfcpp::R_390_GOTPCDBL:
2789     case elfcpp::R_390_GOTOFF16:
2790     case elfcpp::R_390_GOTOFF32:
2791     case elfcpp::R_390_GOTOFF64:
2792     case elfcpp::R_390_PLTOFF16:
2793     case elfcpp::R_390_PLTOFF32:
2794     case elfcpp::R_390_PLTOFF64:
2795       // We need a GOT section.
2796       target->got_section(symtab, layout);
2797       // For PLTOFF*, we also need a PLT entry (but only if the
2798       // symbol is not fully resolved).
2799       if ((r_type == elfcpp::R_390_PLTOFF16
2800            || r_type == elfcpp::R_390_PLTOFF32
2801 	   || r_type == elfcpp::R_390_PLTOFF64)
2802 	  && !gsym->final_value_is_known())
2803 	target->make_plt_entry(symtab, layout, gsym);
2804       break;
2805 
2806     case elfcpp::R_390_GOT12:
2807     case elfcpp::R_390_GOT16:
2808     case elfcpp::R_390_GOT20:
2809     case elfcpp::R_390_GOT32:
2810     case elfcpp::R_390_GOT64:
2811     case elfcpp::R_390_GOTENT:
2812     case elfcpp::R_390_GOTPLT12:
2813     case elfcpp::R_390_GOTPLT16:
2814     case elfcpp::R_390_GOTPLT20:
2815     case elfcpp::R_390_GOTPLT32:
2816     case elfcpp::R_390_GOTPLT64:
2817     case elfcpp::R_390_GOTPLTENT:
2818       {
2819 	// The symbol requires a GOT entry.
2820 	Output_data_got<size, true>* got = target->got_section(symtab, layout);
2821 
2822 	if (gsym->final_value_is_known())
2823 	  {
2824 	    // For a STT_GNU_IFUNC symbol we want the PLT address.
2825 	    if (gsym->type() == elfcpp::STT_GNU_IFUNC)
2826 	      got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2827 	    else
2828 	      got->add_global(gsym, GOT_TYPE_STANDARD);
2829 	  }
2830 	else
2831 	  {
2832 	    // If this symbol is not fully resolved, we need to add a
2833 	    // dynamic relocation for it.
2834 	    Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2835 
2836 	    // Use a GLOB_DAT rather than a RELATIVE reloc if:
2837 	    //
2838 	    // 1) The symbol may be defined in some other module.
2839 	    //
2840 	    // 2) We are building a shared library and this is a
2841 	    // protected symbol; using GLOB_DAT means that the dynamic
2842 	    // linker can use the address of the PLT in the main
2843 	    // executable when appropriate so that function address
2844 	    // comparisons work.
2845 	    //
2846 	    // 3) This is a STT_GNU_IFUNC symbol in position dependent
2847 	    // code, again so that function address comparisons work.
2848 	    if (gsym->is_from_dynobj()
2849 		|| gsym->is_undefined()
2850 		|| gsym->is_preemptible()
2851 		|| (gsym->visibility() == elfcpp::STV_PROTECTED
2852 		    && parameters->options().shared())
2853 		|| (gsym->type() == elfcpp::STT_GNU_IFUNC
2854 		    && parameters->options().output_is_position_independent()))
2855 	      got->add_global_with_rel(gsym, GOT_TYPE_STANDARD, rela_dyn,
2856 				       elfcpp::R_390_GLOB_DAT);
2857 	    else
2858 	      {
2859 		// For a STT_GNU_IFUNC symbol we want to write the PLT
2860 		// offset into the GOT, so that function pointer
2861 		// comparisons work correctly.
2862 		bool is_new;
2863 		if (gsym->type() != elfcpp::STT_GNU_IFUNC)
2864 		  is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
2865 		else
2866 		  {
2867 		    is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2868 		    // Tell the dynamic linker to use the PLT address
2869 		    // when resolving relocations.
2870 		    if (gsym->is_from_dynobj()
2871 			&& !parameters->options().shared())
2872 		      gsym->set_needs_dynsym_value();
2873 		  }
2874 		if (is_new)
2875 		  {
2876 		    unsigned int got_off = gsym->got_offset(GOT_TYPE_STANDARD);
2877 		    rela_dyn->add_global_relative(gsym,
2878 						  elfcpp::R_390_RELATIVE,
2879 						  got, got_off, 0, false);
2880 		  }
2881 	      }
2882 	  }
2883       }
2884       break;
2885 
2886     case elfcpp::R_390_COPY:
2887     case elfcpp::R_390_GLOB_DAT:
2888     case elfcpp::R_390_JMP_SLOT:
2889     case elfcpp::R_390_RELATIVE:
2890     case elfcpp::R_390_IRELATIVE:
2891       // These are outstanding tls relocs, which are unexpected when linking
2892     case elfcpp::R_390_TLS_TPOFF:
2893     case elfcpp::R_390_TLS_DTPOFF:
2894     case elfcpp::R_390_TLS_DTPMOD:
2895       gold_error(_("%s: unexpected reloc %u in object file"),
2896 		 object->name().c_str(), r_type);
2897       break;
2898 
2899       // These are initial tls relocs, which are expected for global()
2900     case elfcpp::R_390_TLS_GD32:          // Global-dynamic
2901     case elfcpp::R_390_TLS_GD64:
2902     case elfcpp::R_390_TLS_GDCALL:
2903     case elfcpp::R_390_TLS_LDM32:         // Local-dynamic
2904     case elfcpp::R_390_TLS_LDM64:
2905     case elfcpp::R_390_TLS_LDO32:
2906     case elfcpp::R_390_TLS_LDO64:
2907     case elfcpp::R_390_TLS_LDCALL:
2908     case elfcpp::R_390_TLS_IE32:          // Initial-exec
2909     case elfcpp::R_390_TLS_IE64:
2910     case elfcpp::R_390_TLS_IEENT:
2911     case elfcpp::R_390_TLS_GOTIE12:
2912     case elfcpp::R_390_TLS_GOTIE20:
2913     case elfcpp::R_390_TLS_GOTIE32:
2914     case elfcpp::R_390_TLS_GOTIE64:
2915     case elfcpp::R_390_TLS_LOAD:
2916     case elfcpp::R_390_TLS_LE32:          // Local-exec
2917     case elfcpp::R_390_TLS_LE64:
2918       {
2919 	// For the optimizable Initial-Exec model, we can treat undef symbols
2920 	// as final when building an executable.
2921 	const bool is_final = (gsym->final_value_is_known() ||
2922 			       ((r_type == elfcpp::R_390_TLS_IE32 ||
2923 			         r_type == elfcpp::R_390_TLS_IE64 ||
2924 			         r_type == elfcpp::R_390_TLS_GOTIE32 ||
2925 			         r_type == elfcpp::R_390_TLS_GOTIE64) &&
2926 			        gsym->is_undefined() &&
2927 				parameters->options().output_is_executable()));
2928 	const tls::Tls_optimization optimized_type
2929 	    = Target_s390<size>::optimize_tls_reloc(is_final, r_type);
2930 	switch (r_type)
2931 	  {
2932 	  case elfcpp::R_390_TLS_GD32:       // General-dynamic
2933 	  case elfcpp::R_390_TLS_GD64:
2934 	  case elfcpp::R_390_TLS_GDCALL:
2935 	    if (optimized_type == tls::TLSOPT_NONE)
2936 	      {
2937 		// Create a pair of GOT entries for the module index and
2938 		// dtv-relative offset.
2939 		Output_data_got<size, true>* got
2940 		    = target->got_section(symtab, layout);
2941 		got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
2942 					      target->rela_dyn_section(layout),
2943 					      elfcpp::R_390_TLS_DTPMOD,
2944 					      elfcpp::R_390_TLS_DTPOFF);
2945 	      }
2946 	    else if (optimized_type == tls::TLSOPT_TO_IE)
2947 	      {
2948 		// Create a GOT entry for the tp-relative offset.
2949 		Output_data_got<size, true>* got
2950 		    = target->got_section(symtab, layout);
2951 		got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
2952 					 target->rela_dyn_section(layout),
2953 					 elfcpp::R_390_TLS_TPOFF);
2954 	      }
2955 	    else if (optimized_type != tls::TLSOPT_TO_LE)
2956 	      unsupported_reloc_global(object, r_type, gsym);
2957 	    break;
2958 
2959 	  case elfcpp::R_390_TLS_LDM32:       // Local-dynamic
2960 	  case elfcpp::R_390_TLS_LDM64:
2961 	  case elfcpp::R_390_TLS_LDCALL:
2962 	    if (optimized_type == tls::TLSOPT_NONE)
2963 	      {
2964 		// Create a GOT entry for the module index.
2965 		target->got_mod_index_entry(symtab, layout, object);
2966 	      }
2967 	    else if (optimized_type != tls::TLSOPT_TO_LE)
2968 	      unsupported_reloc_global(object, r_type, gsym);
2969 	    break;
2970 
2971 	  case elfcpp::R_390_TLS_LDO32:
2972 	  case elfcpp::R_390_TLS_LDO64:
2973 	    break;
2974 
2975 	  case elfcpp::R_390_TLS_IE32:    // Initial-exec
2976 	  case elfcpp::R_390_TLS_IE64:
2977 	    // These two involve an absolute address
2978 	    if (parameters->options().shared())
2979 	      {
2980 		if ((size == 32 && r_type == elfcpp::R_390_TLS_IE32) ||
2981 		    (size == 64 && r_type == elfcpp::R_390_TLS_IE64))
2982 		  {
2983 		    // We need to create a dynamic relocation.
2984 		    Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2985 		    rela_dyn->add_global_relative(gsym, elfcpp::R_390_RELATIVE,
2986 						  output_section, object,
2987 						  data_shndx,
2988 						  reloc.get_r_offset(),
2989 						  reloc.get_r_addend(), false);
2990 		  }
2991 		else
2992 		  {
2993 		    unsupported_reloc_global(object, r_type, gsym);
2994 		  }
2995 	      }
2996 	    // fall through
2997 	  case elfcpp::R_390_TLS_IEENT:
2998 	  case elfcpp::R_390_TLS_GOTIE12:
2999 	  case elfcpp::R_390_TLS_GOTIE20:
3000 	  case elfcpp::R_390_TLS_GOTIE32:
3001 	  case elfcpp::R_390_TLS_GOTIE64:
3002 	  case elfcpp::R_390_TLS_LOAD:
3003 	    layout->set_has_static_tls();
3004 	    if (optimized_type == tls::TLSOPT_NONE)
3005 	      {
3006 		if (is_final && !parameters->options().shared())
3007 		  {
3008 		    // We're making an executable, and the symbol is local, but
3009 		    // we cannot optimize to LE.  Make a const GOT entry instead.
3010 		    Output_data_got<size, true>* got
3011 			= target->got_section(symtab, layout);
3012 		    got->add_global_plt(gsym, GOT_TYPE_TLS_OFFSET);
3013 		  }
3014 		else
3015 		  {
3016 		    // Create a GOT entry for the tp-relative offset.
3017 		    Output_data_got<size, true>* got
3018 			= target->got_section(symtab, layout);
3019 		    got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
3020 					     target->rela_dyn_section(layout),
3021 					     elfcpp::R_390_TLS_TPOFF);
3022 		  }
3023 	      }
3024 	    else if (optimized_type != tls::TLSOPT_TO_LE)
3025 	      unsupported_reloc_global(object, r_type, gsym);
3026 	    break;
3027 
3028 	  case elfcpp::R_390_TLS_LE32:     // Local-exec
3029 	  case elfcpp::R_390_TLS_LE64:
3030 	    layout->set_has_static_tls();
3031 	    if (parameters->options().shared())
3032 	      {
3033 		// We need to create a dynamic relocation.
3034 		if ((size == 32 && r_type == elfcpp::R_390_TLS_LE32) ||
3035 		    (size == 64 && r_type == elfcpp::R_390_TLS_LE64))
3036 		  {
3037 		    Reloc_section* rela_dyn = target->rela_dyn_section(layout);
3038 		    rela_dyn->add_global(gsym, elfcpp::R_390_TLS_TPOFF,
3039 					 output_section, object,
3040 					 data_shndx, reloc.get_r_offset(),
3041 					 reloc.get_r_addend());
3042 		  }
3043 		else
3044 		  {
3045 		    unsupported_reloc_global(object, r_type, gsym);
3046 		  }
3047 	      }
3048 	    break;
3049 
3050 	  default:
3051 	    gold_unreachable();
3052 	  }
3053       }
3054       break;
3055 
3056     default:
3057       gold_error(_("%s: unsupported reloc %u against global symbol %s"),
3058 		 object->name().c_str(), r_type,
3059 		 gsym->demangled_name().c_str());
3060       break;
3061     }
3062 }
3063 
3064 
3065 // Report an unsupported relocation against a global symbol.
3066 
3067 template<int size>
3068 void
unsupported_reloc_global(Sized_relobj_file<size,true> * object,unsigned int r_type,Symbol * gsym)3069 Target_s390<size>::Scan::unsupported_reloc_global(
3070     Sized_relobj_file<size, true>* object,
3071     unsigned int r_type,
3072     Symbol* gsym)
3073 {
3074   gold_error(_("%s: unsupported reloc %u against global symbol %s"),
3075 	     object->name().c_str(), r_type, gsym->demangled_name().c_str());
3076 }
3077 
3078 // Returns true if this relocation type could be that of a function pointer.
3079 template<int size>
3080 inline bool
possible_function_pointer_reloc(unsigned int r_type)3081 Target_s390<size>::Scan::possible_function_pointer_reloc(unsigned int r_type)
3082 {
3083   switch (r_type)
3084     {
3085     case elfcpp::R_390_32:
3086     case elfcpp::R_390_64:
3087     case elfcpp::R_390_PC32DBL: // could be used by larl insn
3088     case elfcpp::R_390_GOT12:
3089     case elfcpp::R_390_GOT16:
3090     case elfcpp::R_390_GOT20:
3091     case elfcpp::R_390_GOT32:
3092     case elfcpp::R_390_GOT64:
3093     case elfcpp::R_390_GOTENT:
3094     case elfcpp::R_390_GOTOFF16:
3095     case elfcpp::R_390_GOTOFF32:
3096     case elfcpp::R_390_GOTOFF64:
3097       return true;
3098     }
3099   return false;
3100 }
3101 
3102 // For safe ICF, scan a relocation for a local symbol to check if it
3103 // corresponds to a function pointer being taken.  In that case mark
3104 // the function whose pointer was taken as not foldable.
3105 
3106 template<int size>
3107 inline bool
local_reloc_may_be_function_pointer(Symbol_table *,Layout *,Target_s390<size> *,Sized_relobj_file<size,true> *,unsigned int,Output_section *,const elfcpp::Rela<size,true> &,unsigned int r_type,const elfcpp::Sym<size,true> &)3108 Target_s390<size>::Scan::local_reloc_may_be_function_pointer(
3109   Symbol_table* ,
3110   Layout* ,
3111   Target_s390<size>* ,
3112   Sized_relobj_file<size, true>* ,
3113   unsigned int ,
3114   Output_section* ,
3115   const elfcpp::Rela<size, true>& ,
3116   unsigned int r_type,
3117   const elfcpp::Sym<size, true>&)
3118 {
3119   // When building a shared library, do not fold any local symbols.
3120   return (parameters->options().shared()
3121 	  || possible_function_pointer_reloc(r_type));
3122 }
3123 
3124 // For safe ICF, scan a relocation for a global symbol to check if it
3125 // corresponds to a function pointer being taken.  In that case mark
3126 // the function whose pointer was taken as not foldable.
3127 
3128 template<int size>
3129 inline bool
global_reloc_may_be_function_pointer(Symbol_table *,Layout *,Target_s390<size> *,Sized_relobj_file<size,true> *,unsigned int,Output_section *,const elfcpp::Rela<size,true> &,unsigned int r_type,Symbol * gsym)3130 Target_s390<size>::Scan::global_reloc_may_be_function_pointer(
3131   Symbol_table*,
3132   Layout* ,
3133   Target_s390<size>* ,
3134   Sized_relobj_file<size, true>* ,
3135   unsigned int ,
3136   Output_section* ,
3137   const elfcpp::Rela<size, true>& ,
3138   unsigned int r_type,
3139   Symbol* gsym)
3140 {
3141   // When building a shared library, do not fold symbols whose visibility
3142   // is hidden, internal or protected.
3143   return ((parameters->options().shared()
3144 	   && (gsym->visibility() == elfcpp::STV_INTERNAL
3145 	       || gsym->visibility() == elfcpp::STV_PROTECTED
3146 	       || gsym->visibility() == elfcpp::STV_HIDDEN))
3147 	  || possible_function_pointer_reloc(r_type));
3148 }
3149 
3150 template<int size>
3151 void
gc_process_relocs(Symbol_table * symtab,Layout * layout,Sized_relobj_file<size,true> * object,unsigned int data_shndx,unsigned int sh_type,const unsigned char * prelocs,size_t reloc_count,Output_section * output_section,bool needs_special_offset_handling,size_t local_symbol_count,const unsigned char * plocal_symbols)3152 Target_s390<size>::gc_process_relocs(Symbol_table* symtab,
3153 				       Layout* layout,
3154 				       Sized_relobj_file<size, true>* object,
3155 				       unsigned int data_shndx,
3156 				       unsigned int sh_type,
3157 				       const unsigned char* prelocs,
3158 				       size_t reloc_count,
3159 				       Output_section* output_section,
3160 				       bool needs_special_offset_handling,
3161 				       size_t local_symbol_count,
3162 				       const unsigned char* plocal_symbols)
3163 {
3164   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, true>
3165       Classify_reloc;
3166 
3167   if (sh_type == elfcpp::SHT_REL)
3168     return;
3169 
3170   gold::gc_process_relocs<size, true, Target_s390<size>, Scan, Classify_reloc>(
3171     symtab,
3172     layout,
3173     this,
3174     object,
3175     data_shndx,
3176     prelocs,
3177     reloc_count,
3178     output_section,
3179     needs_special_offset_handling,
3180     local_symbol_count,
3181     plocal_symbols);
3182 }
3183 
3184 // Perform a relocation.
3185 
3186 template<int size>
3187 inline bool
relocate(const Relocate_info<size,true> * relinfo,unsigned int,Target_s390<size> * target,Output_section *,size_t relnum,const unsigned char * preloc,const Sized_symbol<size> * gsym,const Symbol_value<size> * psymval,unsigned char * view,typename elfcpp::Elf_types<size>::Elf_Addr address,section_size_type view_size)3188 Target_s390<size>::Relocate::relocate(
3189     const Relocate_info<size, true>* relinfo,
3190     unsigned int,
3191     Target_s390<size>* target,
3192     Output_section*,
3193     size_t relnum,
3194     const unsigned char* preloc,
3195     const Sized_symbol<size>* gsym,
3196     const Symbol_value<size>* psymval,
3197     unsigned char* view,
3198     typename elfcpp::Elf_types<size>::Elf_Addr address,
3199     section_size_type view_size)
3200 {
3201   if (view == NULL)
3202     return true;
3203 
3204   const elfcpp::Rela<size, true> rela(preloc);
3205   unsigned int r_type = elfcpp::elf_r_type<size>(rela.get_r_info());
3206   const Sized_relobj_file<size, true>* object = relinfo->object;
3207 
3208   // Pick the value to use for symbols defined in the PLT.
3209   Symbol_value<size> symval;
3210   if (gsym != NULL
3211       && gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
3212     {
3213       symval.set_output_value(target->plt_address_for_global(gsym));
3214       psymval = &symval;
3215     }
3216   else if (gsym == NULL && psymval->is_ifunc_symbol())
3217     {
3218       unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3219       if (object->local_has_plt_offset(r_sym))
3220 	{
3221 	  symval.set_output_value(target->plt_address_for_local(object, r_sym));
3222 	  psymval = &symval;
3223 	}
3224     }
3225 
3226   const elfcpp::Elf_Xword addend = rela.get_r_addend();
3227 
3228   typename elfcpp::Elf_types<size>::Elf_Addr value = 0;
3229 
3230   switch (r_type)
3231     {
3232     case elfcpp::R_390_PLT64:
3233     case elfcpp::R_390_PLT32:
3234     case elfcpp::R_390_PLT32DBL:
3235     case elfcpp::R_390_PLT24DBL:
3236     case elfcpp::R_390_PLT16DBL:
3237     case elfcpp::R_390_PLT12DBL:
3238       gold_assert(gsym == NULL
3239 		  || gsym->has_plt_offset()
3240 		  || gsym->final_value_is_known()
3241 		  || (gsym->is_defined()
3242 		      && !gsym->is_from_dynobj()
3243 		      && !gsym->is_preemptible()));
3244       // fallthru
3245     case elfcpp::R_390_8:
3246     case elfcpp::R_390_12:
3247     case elfcpp::R_390_16:
3248     case elfcpp::R_390_20:
3249     case elfcpp::R_390_32:
3250     case elfcpp::R_390_64:
3251     case elfcpp::R_390_PC16:
3252     case elfcpp::R_390_PC32:
3253     case elfcpp::R_390_PC64:
3254     case elfcpp::R_390_PC32DBL:
3255     case elfcpp::R_390_PC24DBL:
3256     case elfcpp::R_390_PC16DBL:
3257     case elfcpp::R_390_PC12DBL:
3258       value = psymval->value(object, addend);
3259       break;
3260 
3261     case elfcpp::R_390_GOTPC:
3262     case elfcpp::R_390_GOTPCDBL:
3263       gold_assert(gsym != NULL);
3264       value = target->got_address() + addend;
3265       break;
3266 
3267     case elfcpp::R_390_PLTOFF64:
3268     case elfcpp::R_390_PLTOFF32:
3269     case elfcpp::R_390_PLTOFF16:
3270       gold_assert(gsym == NULL
3271 		  || gsym->has_plt_offset()
3272 		  || gsym->final_value_is_known());
3273       // fallthru
3274     case elfcpp::R_390_GOTOFF64:
3275     case elfcpp::R_390_GOTOFF32:
3276     case elfcpp::R_390_GOTOFF16:
3277       value = (psymval->value(object, addend)
3278 	       - target->got_address());
3279       break;
3280 
3281     case elfcpp::R_390_GOT12:
3282     case elfcpp::R_390_GOT16:
3283     case elfcpp::R_390_GOT20:
3284     case elfcpp::R_390_GOT32:
3285     case elfcpp::R_390_GOT64:
3286     case elfcpp::R_390_GOTENT:
3287     case elfcpp::R_390_GOTPLT12:
3288     case elfcpp::R_390_GOTPLT16:
3289     case elfcpp::R_390_GOTPLT20:
3290     case elfcpp::R_390_GOTPLT32:
3291     case elfcpp::R_390_GOTPLT64:
3292     case elfcpp::R_390_GOTPLTENT:
3293       {
3294         unsigned int got_offset = 0;
3295         if (gsym != NULL)
3296 	  {
3297 	    gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
3298 	    got_offset = gsym->got_offset(GOT_TYPE_STANDARD);
3299 	  }
3300         else
3301 	  {
3302 	    unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3303 	    gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
3304 	    got_offset = object->local_got_offset(r_sym, GOT_TYPE_STANDARD);
3305 	  }
3306         value = got_offset + target->got_main_offset() + addend;
3307       }
3308       break;
3309 
3310       // These are initial tls relocs, which are expected when linking
3311     case elfcpp::R_390_TLS_LOAD:
3312     case elfcpp::R_390_TLS_GDCALL:          // Global-dynamic
3313     case elfcpp::R_390_TLS_GD32:
3314     case elfcpp::R_390_TLS_GD64:
3315     case elfcpp::R_390_TLS_LDCALL:          // Local-dynamic
3316     case elfcpp::R_390_TLS_LDM32:
3317     case elfcpp::R_390_TLS_LDM64:
3318     case elfcpp::R_390_TLS_LDO32:
3319     case elfcpp::R_390_TLS_LDO64:
3320     case elfcpp::R_390_TLS_GOTIE12:         // Initial-exec
3321     case elfcpp::R_390_TLS_GOTIE20:
3322     case elfcpp::R_390_TLS_GOTIE32:
3323     case elfcpp::R_390_TLS_GOTIE64:
3324     case elfcpp::R_390_TLS_IE32:
3325     case elfcpp::R_390_TLS_IE64:
3326     case elfcpp::R_390_TLS_IEENT:
3327     case elfcpp::R_390_TLS_LE32:            // Local-exec
3328     case elfcpp::R_390_TLS_LE64:
3329       value = this->relocate_tls(relinfo, target, relnum, rela, r_type, gsym, psymval,
3330 			 view, view_size);
3331       break;
3332 
3333     default:
3334       break;
3335     }
3336 
3337   typename S390_relocate_functions<size>::Status status
3338       = S390_relocate_functions<size>::STATUS_OK;
3339 
3340   switch (r_type)
3341     {
3342     case elfcpp::R_390_NONE:
3343     case elfcpp::R_390_GNU_VTINHERIT:
3344     case elfcpp::R_390_GNU_VTENTRY:
3345     case elfcpp::R_390_TLS_GDCALL:
3346     case elfcpp::R_390_TLS_LDCALL:
3347     case elfcpp::R_390_TLS_LOAD:
3348       break;
3349 
3350     case elfcpp::R_390_64:
3351     case elfcpp::R_390_GOT64:
3352     case elfcpp::R_390_GOTPLT64:
3353     case elfcpp::R_390_PLTOFF64:
3354     case elfcpp::R_390_GOTOFF64:
3355     case elfcpp::R_390_TLS_GD64:
3356     case elfcpp::R_390_TLS_LDM64:
3357     case elfcpp::R_390_TLS_LDO64:
3358     case elfcpp::R_390_TLS_GOTIE64:
3359     case elfcpp::R_390_TLS_IE64:
3360     case elfcpp::R_390_TLS_LE64:
3361       Relocate_functions<size, true>::rela64(view, value, 0);
3362       break;
3363 
3364     case elfcpp::R_390_32:
3365     case elfcpp::R_390_GOT32:
3366     case elfcpp::R_390_GOTPLT32:
3367     case elfcpp::R_390_PLTOFF32:
3368     case elfcpp::R_390_GOTOFF32:
3369     case elfcpp::R_390_TLS_GD32:
3370     case elfcpp::R_390_TLS_LDM32:
3371     case elfcpp::R_390_TLS_LDO32:
3372     case elfcpp::R_390_TLS_GOTIE32:
3373     case elfcpp::R_390_TLS_IE32:
3374     case elfcpp::R_390_TLS_LE32:
3375       Relocate_functions<size, true>::rela32(view, value, 0);
3376       break;
3377 
3378     case elfcpp::R_390_20:
3379     case elfcpp::R_390_GOT20:
3380     case elfcpp::R_390_GOTPLT20:
3381     case elfcpp::R_390_TLS_GOTIE20:
3382       status = S390_relocate_functions<size>::rela20(view, value);
3383       break;
3384 
3385     case elfcpp::R_390_16:
3386     case elfcpp::R_390_GOT16:
3387     case elfcpp::R_390_GOTPLT16:
3388     case elfcpp::R_390_PLTOFF16:
3389     case elfcpp::R_390_GOTOFF16:
3390       status = S390_relocate_functions<size>::rela16(view, value);
3391       break;
3392 
3393     case elfcpp::R_390_12:
3394     case elfcpp::R_390_GOT12:
3395     case elfcpp::R_390_GOTPLT12:
3396     case elfcpp::R_390_TLS_GOTIE12:
3397       status = S390_relocate_functions<size>::rela12(view, value);
3398       break;
3399 
3400     case elfcpp::R_390_8:
3401       Relocate_functions<size, true>::rela8(view, value, 0);
3402       break;
3403 
3404     case elfcpp::R_390_PC16:
3405       Relocate_functions<size, true>::pcrela16(view, value, 0,
3406 					       address);
3407       break;
3408 
3409     case elfcpp::R_390_PLT64:
3410     case elfcpp::R_390_PC64:
3411       Relocate_functions<size, true>::pcrela64(view, value, 0, address);
3412       break;
3413 
3414     case elfcpp::R_390_PLT32:
3415     case elfcpp::R_390_PC32:
3416     case elfcpp::R_390_GOTPC:
3417       Relocate_functions<size, true>::pcrela32(view, value, 0, address);
3418       break;
3419 
3420     case elfcpp::R_390_PLT32DBL:
3421     case elfcpp::R_390_PC32DBL:
3422     case elfcpp::R_390_GOTPCDBL:
3423       status = S390_relocate_functions<size>::pcrela32dbl(view, value, address);
3424       break;
3425 
3426     case elfcpp::R_390_PLT24DBL:
3427     case elfcpp::R_390_PC24DBL:
3428       status = S390_relocate_functions<size>::pcrela24dbl(view, value, address);
3429       break;
3430 
3431     case elfcpp::R_390_PLT16DBL:
3432     case elfcpp::R_390_PC16DBL:
3433       status = S390_relocate_functions<size>::pcrela16dbl(view, value, address);
3434       break;
3435 
3436     case elfcpp::R_390_PLT12DBL:
3437     case elfcpp::R_390_PC12DBL:
3438       status = S390_relocate_functions<size>::pcrela12dbl(view, value, address);
3439       break;
3440 
3441     case elfcpp::R_390_GOTENT:
3442     case elfcpp::R_390_GOTPLTENT:
3443     case elfcpp::R_390_TLS_IEENT:
3444       value += target->got_address();
3445       status = S390_relocate_functions<size>::pcrela32dbl(view, value, address);
3446       break;
3447 
3448     case elfcpp::R_390_COPY:
3449     case elfcpp::R_390_GLOB_DAT:
3450     case elfcpp::R_390_JMP_SLOT:
3451     case elfcpp::R_390_RELATIVE:
3452     case elfcpp::R_390_IRELATIVE:
3453       // These are outstanding tls relocs, which are unexpected when linking
3454     case elfcpp::R_390_TLS_TPOFF:
3455     case elfcpp::R_390_TLS_DTPMOD:
3456     case elfcpp::R_390_TLS_DTPOFF:
3457       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3458 			     _("unexpected reloc %u in object file"),
3459 			     r_type);
3460       break;
3461 
3462     default:
3463       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3464 			     _("unsupported reloc %u"),
3465 			     r_type);
3466       break;
3467     }
3468 
3469   if (status != S390_relocate_functions<size>::STATUS_OK)
3470     {
3471       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3472 			     _("relocation overflow"));
3473     }
3474 
3475   return true;
3476 }
3477 
3478 // Perform a TLS relocation.
3479 
3480 template<int size>
3481 inline typename elfcpp::Elf_types<size>::Elf_Addr
relocate_tls(const Relocate_info<size,true> * relinfo,Target_s390<size> * target,size_t relnum,const elfcpp::Rela<size,true> & rela,unsigned int r_type,const Sized_symbol<size> * gsym,const Symbol_value<size> * psymval,unsigned char * view,section_size_type view_size)3482 Target_s390<size>::Relocate::relocate_tls(
3483     const Relocate_info<size, true>* relinfo,
3484     Target_s390<size>* target,
3485     size_t relnum,
3486     const elfcpp::Rela<size, true>& rela,
3487     unsigned int r_type,
3488     const Sized_symbol<size>* gsym,
3489     const Symbol_value<size>* psymval,
3490     unsigned char* view,
3491     section_size_type view_size)
3492 {
3493   Output_segment* tls_segment = relinfo->layout->tls_segment();
3494 
3495   const Sized_relobj_file<size, true>* object = relinfo->object;
3496   const elfcpp::Elf_Xword addend = rela.get_r_addend();
3497   elfcpp::Shdr<size, true> data_shdr(relinfo->data_shdr);
3498   bool is_allocatable = (data_shdr.get_sh_flags() & elfcpp::SHF_ALLOC) != 0;
3499 
3500   typename elfcpp::Elf_types<size>::Elf_Addr value
3501       = psymval->value(relinfo->object, addend);
3502 
3503   const bool is_final = (gsym == NULL
3504 			 ? !parameters->options().shared()
3505 			 : gsym->final_value_is_known());
3506   tls::Tls_optimization optimized_type
3507       = Target_s390<size>::optimize_tls_reloc(is_final, r_type);
3508   switch (r_type)
3509     {
3510     case elfcpp::R_390_TLS_GDCALL:            // Global-dynamic marker
3511       if (optimized_type == tls::TLSOPT_TO_LE)
3512 	{
3513 	  if (tls_segment == NULL)
3514 	    {
3515 	      gold_assert(parameters->errors()->error_count() > 0
3516 			  || issue_undefined_symbol_error(gsym));
3517 	      return 0;
3518 	    }
3519 	  this->tls_gd_to_le(relinfo, relnum, rela, view, view_size);
3520 	  break;
3521 	}
3522       else
3523 	{
3524 	  if (optimized_type == tls::TLSOPT_TO_IE)
3525 	    {
3526 	      this->tls_gd_to_ie(relinfo, relnum, rela, view, view_size);
3527 	      break;
3528 	    }
3529 	  else if (optimized_type == tls::TLSOPT_NONE)
3530 	    {
3531 	      break;
3532 	    }
3533 	}
3534       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3535 			     _("unsupported reloc %u"), r_type);
3536       break;
3537 
3538     case elfcpp::R_390_TLS_GD32:            // Global-dynamic
3539     case elfcpp::R_390_TLS_GD64:
3540       if (optimized_type == tls::TLSOPT_TO_LE)
3541 	{
3542 	  if (tls_segment == NULL)
3543 	    {
3544 	      gold_assert(parameters->errors()->error_count() > 0
3545 			  || issue_undefined_symbol_error(gsym));
3546 	      return 0;
3547 	    }
3548 	  return value - tls_segment->memsz();
3549 	}
3550       else
3551 	{
3552 	  unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3553 				   ? GOT_TYPE_TLS_OFFSET
3554 				   : GOT_TYPE_TLS_PAIR);
3555 	  if (gsym != NULL)
3556 	    {
3557 	      gold_assert(gsym->has_got_offset(got_type));
3558 	      return (gsym->got_offset(got_type)
3559 		      + target->got_main_offset()
3560 		      + addend);
3561 	    }
3562 	  else
3563 	    {
3564 	      unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3565 	      gold_assert(object->local_has_got_offset(r_sym, got_type));
3566 	      return (object->local_got_offset(r_sym, got_type)
3567 		      + target->got_main_offset()
3568 		      + addend);
3569 	    }
3570 	}
3571       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3572 			     _("unsupported reloc %u"), r_type);
3573       break;
3574 
3575     case elfcpp::R_390_TLS_LDCALL:            // Local-dynamic marker
3576       // This is a marker relocation. If the sequence is being turned to LE,
3577       // we modify the instruction, otherwise the instruction is untouched.
3578       if (optimized_type == tls::TLSOPT_TO_LE)
3579 	{
3580 	  if (tls_segment == NULL)
3581 	    {
3582 	      gold_assert(parameters->errors()->error_count() > 0
3583 			  || issue_undefined_symbol_error(gsym));
3584 	      return 0;
3585 	    }
3586 	  this->tls_ld_to_le(relinfo, relnum, rela, view, view_size);
3587 	  break;
3588 	}
3589       else if (optimized_type == tls::TLSOPT_NONE)
3590 	{
3591 	  break;
3592 	}
3593       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3594 			     _("unsupported reloc %u"), r_type);
3595       break;
3596 
3597     case elfcpp::R_390_TLS_LDM32:            // Local-dynamic module
3598     case elfcpp::R_390_TLS_LDM64:
3599       if (optimized_type == tls::TLSOPT_TO_LE)
3600 	{
3601 	  if (tls_segment == NULL)
3602 	    {
3603 	      gold_assert(parameters->errors()->error_count() > 0
3604 			  || issue_undefined_symbol_error(gsym));
3605 	      return 0;
3606 	    }
3607 	  // Doesn't matter what we fill it with - it's going to be unused.
3608 	  return 0;
3609 	}
3610       else if (optimized_type == tls::TLSOPT_NONE)
3611 	{
3612 	  // Relocate the field with the offset of the GOT entry for
3613 	  // the module index.
3614 	  return (target->got_mod_index_entry(NULL, NULL, NULL)
3615 		  + addend
3616 		  + target->got_main_offset());
3617 	}
3618       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3619 			     _("unsupported reloc %u"), r_type);
3620       break;
3621 
3622     case elfcpp::R_390_TLS_LDO32:         // Local-dynamic offset
3623     case elfcpp::R_390_TLS_LDO64:
3624       // This relocation type is used in debugging information.
3625       // In that case we need to not optimize the value.  If the
3626       // section is not allocatable, then we assume we should not
3627       // optimize this reloc.
3628       if (optimized_type == tls::TLSOPT_TO_LE && is_allocatable)
3629 	{
3630 	  if (tls_segment == NULL)
3631 	    {
3632 	      gold_assert(parameters->errors()->error_count() > 0
3633 			  || issue_undefined_symbol_error(gsym));
3634 	      return 0;
3635 	    }
3636 	  value -= tls_segment->memsz();
3637 	}
3638       return value;
3639 
3640     case elfcpp::R_390_TLS_LOAD:         // Initial-exec marker
3641       // This is a marker relocation. If the sequence is being turned to LE,
3642       // we modify the instruction, otherwise the instruction is untouched.
3643       if (gsym != NULL
3644 	  && gsym->is_undefined()
3645 	  && parameters->options().output_is_executable())
3646 	{
3647 	  Target_s390<size>::Relocate::tls_ie_to_le(relinfo, relnum,
3648 						      rela, view,
3649 						      view_size);
3650 	  break;
3651 	}
3652       else if (optimized_type == tls::TLSOPT_TO_LE)
3653 	{
3654 	  if (tls_segment == NULL)
3655 	    {
3656 	      gold_assert(parameters->errors()->error_count() > 0
3657 			  || issue_undefined_symbol_error(gsym));
3658 	      return 0;
3659 	    }
3660 	  Target_s390<size>::Relocate::tls_ie_to_le(relinfo, relnum,
3661 						      rela, view,
3662 						      view_size);
3663 	  break;
3664 	}
3665       else if (optimized_type == tls::TLSOPT_NONE)
3666 	{
3667 	  break;
3668 	}
3669       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3670 			     _("unsupported reloc type %u"),
3671 			     r_type);
3672       break;
3673 
3674     case elfcpp::R_390_TLS_GOTIE12:       // Initial-exec, not optimizable
3675     case elfcpp::R_390_TLS_GOTIE20:
3676     case elfcpp::R_390_TLS_IEENT:
3677     case elfcpp::R_390_TLS_GOTIE32:       // Initial-exec, optimizable
3678     case elfcpp::R_390_TLS_GOTIE64:
3679     case elfcpp::R_390_TLS_IE32:
3680     case elfcpp::R_390_TLS_IE64:
3681       if (gsym != NULL
3682 	  && gsym->is_undefined()
3683 	  && parameters->options().output_is_executable()
3684 	  // These three cannot be optimized to LE, no matter what
3685 	  && r_type != elfcpp::R_390_TLS_GOTIE12
3686 	  && r_type != elfcpp::R_390_TLS_GOTIE20
3687 	  && r_type != elfcpp::R_390_TLS_IEENT)
3688 	{
3689           return value;
3690 	}
3691       else if (optimized_type == tls::TLSOPT_TO_LE)
3692 	{
3693 	  if (tls_segment == NULL)
3694 	    {
3695 	      gold_assert(parameters->errors()->error_count() > 0
3696 			  || issue_undefined_symbol_error(gsym));
3697 	      return 0;
3698 	    }
3699           return value - tls_segment->memsz();
3700 	}
3701       else if (optimized_type == tls::TLSOPT_NONE)
3702 	{
3703 	  // Relocate the field with the offset of the GOT entry for
3704 	  // the tp-relative offset of the symbol.
3705 	  unsigned int got_offset;
3706 	  if (gsym != NULL)
3707 	    {
3708 	      gold_assert(gsym->has_got_offset(GOT_TYPE_TLS_OFFSET));
3709 	      got_offset = gsym->got_offset(GOT_TYPE_TLS_OFFSET);
3710 	    }
3711 	  else
3712 	    {
3713 	      unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3714 	      gold_assert(object->local_has_got_offset(r_sym,
3715 						       GOT_TYPE_TLS_OFFSET));
3716 	      got_offset = object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET);
3717 	    }
3718 	  got_offset += target->got_main_offset();
3719 	  if (r_type == elfcpp::R_390_TLS_IE32
3720 	      || r_type == elfcpp::R_390_TLS_IE64)
3721 	    return target->got_address() + got_offset + addend;
3722 	  else
3723 	    return got_offset + addend;
3724 	}
3725       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3726 			     _("unsupported reloc type %u"),
3727 			     r_type);
3728       break;
3729 
3730     case elfcpp::R_390_TLS_LE32:          // Local-exec
3731     case elfcpp::R_390_TLS_LE64:
3732       if (tls_segment == NULL)
3733 	{
3734 	  gold_assert(parameters->errors()->error_count() > 0
3735 		      || issue_undefined_symbol_error(gsym));
3736 	  return 0;
3737 	}
3738       return value - tls_segment->memsz();
3739     }
3740   return 0;
3741 }
3742 
3743 // Do a relocation in which we convert a TLS General-Dynamic to an
3744 // Initial-Exec.
3745 
3746 template<int size>
3747 inline void
tls_gd_to_ie(const Relocate_info<size,true> * relinfo,size_t relnum,const elfcpp::Rela<size,true> & rela,unsigned char * view,section_size_type view_size)3748 Target_s390<size>::Relocate::tls_gd_to_ie(
3749     const Relocate_info<size, true>* relinfo,
3750     size_t relnum,
3751     const elfcpp::Rela<size, true>& rela,
3752     unsigned char* view,
3753     section_size_type view_size)
3754 {
3755   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
3756   if (view[0] == 0x4d)
3757     {
3758       // bas, don't care about details
3759       // Change to l %r2, 0(%r2, %r12)
3760       view[0] = 0x58;
3761       view[1] = 0x22;
3762       view[2] = 0xc0;
3763       view[3] = 0x00;
3764       return;
3765     }
3766   else if (view[0] == 0xc0)
3767     {
3768       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 6);
3769       // brasl %r14, __tls_get_offset@plt
3770       if (view[1] == 0xe5)
3771 	{
3772 	  // Change to l/lg %r2, 0(%r2, %r12)
3773 	  // There was a PLT32DBL reloc at the last 4 bytes, overwrite its result.
3774 	  if (size == 32)
3775 	    {
3776 	      // l
3777 	      view[0] = 0x58;
3778 	      view[1] = 0x22;
3779 	      view[2] = 0xc0;
3780 	      view[3] = 0x00;
3781 	      // nop
3782 	      view[4] = 0x07;
3783 	      view[5] = 0x07;
3784 	    }
3785 	  else
3786 	    {
3787 	      // lg
3788 	      view[0] = 0xe3;
3789 	      view[1] = 0x22;
3790 	      view[2] = 0xc0;
3791 	      view[3] = 0;
3792 	      view[4] = 0;
3793 	      view[5] = 0x04;
3794 	    }
3795 	  return;
3796 	}
3797     }
3798   gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3799 			 _("unsupported op for GD to IE"));
3800 }
3801 
3802 // Do a relocation in which we convert a TLS General-Dynamic to a
3803 // Local-Exec.
3804 
3805 template<int size>
3806 inline void
tls_gd_to_le(const Relocate_info<size,true> * relinfo,size_t relnum,const elfcpp::Rela<size,true> & rela,unsigned char * view,section_size_type view_size)3807 Target_s390<size>::Relocate::tls_gd_to_le(
3808     const Relocate_info<size, true>* relinfo,
3809     size_t relnum,
3810     const elfcpp::Rela<size, true>& rela,
3811     unsigned char* view,
3812     section_size_type view_size)
3813 {
3814   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
3815   if (view[0] == 0x0d)
3816     {
3817       // basr, change to nop
3818       view[0] = 0x07;
3819       view[1] = 0x07;
3820     }
3821   else if (view[0] == 0x4d)
3822     {
3823       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
3824       // bas, don't care about details, change to nop
3825       view[0] = 0x47;
3826       view[1] = 0;
3827       view[2] = 0;
3828       view[3] = 0;
3829       return;
3830     }
3831   else if (view[0] == 0xc0)
3832     {
3833       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 6);
3834       // brasl %r14, __tls_get_offset@plt
3835       if (view[1] == 0xe5)
3836 	{
3837 	  // Change to nop jump. There was a PLT32DBL reloc at the last
3838 	  // 4 bytes, overwrite its result.
3839 	  view[1] = 0x04;
3840 	  view[2] = 0;
3841 	  view[3] = 0;
3842 	  view[4] = 0;
3843 	  view[5] = 0;
3844 	  return;
3845 	}
3846     }
3847   gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3848 			 _("unsupported op for GD to LE"));
3849 }
3850 
3851 template<int size>
3852 inline void
tls_ld_to_le(const Relocate_info<size,true> * relinfo,size_t relnum,const elfcpp::Rela<size,true> & rela,unsigned char * view,section_size_type view_size)3853 Target_s390<size>::Relocate::tls_ld_to_le(
3854     const Relocate_info<size, true>* relinfo,
3855     size_t relnum,
3856     const elfcpp::Rela<size, true>& rela,
3857     unsigned char* view,
3858     section_size_type view_size)
3859 {
3860   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
3861 
3862   if (view[0] == 0x0d)
3863     {
3864       // basr, change to nop
3865       view[0] = 0x07;
3866       view[1] = 0x07;
3867     }
3868   else if (view[0] == 0x4d)
3869     {
3870       // bas, don't care about details, change to nop
3871       view[0] = 0x47;
3872       view[1] = 0;
3873       view[2] = 0;
3874       view[3] = 0;
3875       return;
3876     }
3877   else if (view[0] == 0xc0)
3878     {
3879       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 6);
3880       // brasl %r14, __tls_get_offset@plt
3881       if (view[1] == 0xe5)
3882 	{
3883 	  // Change to nop jump. There was a PLT32DBL reloc at the last
3884 	  // 4 bytes, overwrite its result.
3885 	  view[1] = 0x04;
3886 	  view[2] = 0;
3887 	  view[3] = 0;
3888 	  view[4] = 0;
3889 	  view[5] = 0;
3890 	  return;
3891 	}
3892     }
3893   gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3894 			 _("unsupported op for LD to LE"));
3895 }
3896 
3897 // Do a relocation in which we convert a TLS Initial-Exec to a
3898 // Local-Exec.
3899 
3900 template<int size>
3901 inline void
tls_ie_to_le(const Relocate_info<size,true> * relinfo,size_t relnum,const elfcpp::Rela<size,true> & rela,unsigned char * view,section_size_type view_size)3902 Target_s390<size>::Relocate::tls_ie_to_le(
3903     const Relocate_info<size, true>* relinfo,
3904     size_t relnum,
3905     const elfcpp::Rela<size, true>& rela,
3906     unsigned char* view,
3907     section_size_type view_size)
3908 {
3909   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
3910 
3911   if (view[0] == 0x58)
3912     {
3913       // l %rX, 0(%rY) or l %rX, 0(%rY, %r12)
3914       if ((view[2] & 0x0f) != 0 || view[3] != 0)
3915 	goto err;
3916       int rx = view[1] >> 4 & 0xf;
3917       int ry = view[1] & 0xf;
3918       int rz = view[2] >> 4 & 0xf;
3919       if (rz == 0)
3920 	{
3921 	}
3922       else if (ry == 0)
3923 	{
3924 	  ry = rz;
3925 	}
3926       else if (rz == 12)
3927 	{
3928 	}
3929       else if (ry == 12)
3930 	{
3931 	  ry = rz;
3932 	}
3933       else
3934 	goto err;
3935       // to lr %rX, $rY
3936       view[0] = 0x18;
3937       view[1] = rx << 4 | ry;
3938       // and insert a nop
3939       view[2] = 0x07;
3940       view[3] = 0x00;
3941     }
3942   else if (view[0] == 0xe3)
3943     {
3944       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 6);
3945       // lg %rX, 0(%rY) or lg %rX, 0(%rY, %r12)
3946       if ((view[2] & 0x0f) != 0 ||
3947 	  view[3] != 0 ||
3948 	  view[4] != 0 ||
3949 	  view[5] != 0x04)
3950 	goto err;
3951       int rx = view[1] >> 4 & 0xf;
3952       int ry = view[1] & 0xf;
3953       int rz = view[2] >> 4 & 0xf;
3954       if (rz == 0)
3955 	{
3956 	}
3957       else if (ry == 0)
3958 	{
3959 	  ry = rz;
3960 	}
3961       else if (rz == 12)
3962 	{
3963 	}
3964       else if (ry == 12)
3965 	{
3966 	  ry = rz;
3967 	}
3968       else
3969 	goto err;
3970       // to sllg %rX, $rY, 0
3971       view[0] = 0xeb;
3972       view[1] = rx << 4 | ry;
3973       view[2] = 0x00;
3974       view[3] = 0x00;
3975       view[4] = 0x00;
3976       view[5] = 0x0d;
3977     }
3978   else
3979     {
3980 err:
3981       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3982 			     _("unsupported op for IE to LE"));
3983     }
3984 }
3985 
3986 // Scan relocations for a section.
3987 
3988 template<int size>
3989 void
scan_relocs(Symbol_table * symtab,Layout * layout,Sized_relobj_file<size,true> * object,unsigned int data_shndx,unsigned int sh_type,const unsigned char * prelocs,size_t reloc_count,Output_section * output_section,bool needs_special_offset_handling,size_t local_symbol_count,const unsigned char * plocal_symbols)3990 Target_s390<size>::scan_relocs(Symbol_table* symtab,
3991 				 Layout* layout,
3992 				 Sized_relobj_file<size, true>* object,
3993 				 unsigned int data_shndx,
3994 				 unsigned int sh_type,
3995 				 const unsigned char* prelocs,
3996 				 size_t reloc_count,
3997 				 Output_section* output_section,
3998 				 bool needs_special_offset_handling,
3999 				 size_t local_symbol_count,
4000 				 const unsigned char* plocal_symbols)
4001 {
4002   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, true>
4003       Classify_reloc;
4004 
4005   if (sh_type == elfcpp::SHT_REL)
4006     {
4007       gold_error(_("%s: unsupported REL reloc section"),
4008 		 object->name().c_str());
4009       return;
4010     }
4011 
4012   gold::scan_relocs<size, true, Target_s390<size>, Scan, Classify_reloc>(
4013     symtab,
4014     layout,
4015     this,
4016     object,
4017     data_shndx,
4018     prelocs,
4019     reloc_count,
4020     output_section,
4021     needs_special_offset_handling,
4022     local_symbol_count,
4023     plocal_symbols);
4024 }
4025 
4026 // Finalize the sections.
4027 
4028 template<int size>
4029 void
do_finalize_sections(Layout * layout,const Input_objects *,Symbol_table * symtab)4030 Target_s390<size>::do_finalize_sections(
4031     Layout* layout,
4032     const Input_objects*,
4033     Symbol_table* symtab)
4034 {
4035   const Reloc_section* rel_plt = (this->plt_ == NULL
4036 				  ? NULL
4037 				  : this->plt_->rela_plt());
4038   layout->add_target_dynamic_tags(false, this->got_plt_, rel_plt,
4039 				  this->rela_dyn_, true, size == 32);
4040 
4041   this->layout_ = layout;
4042 
4043   // Emit any relocs we saved in an attempt to avoid generating COPY
4044   // relocs.
4045   if (this->copy_relocs_.any_saved_relocs())
4046     this->copy_relocs_.emit(this->rela_dyn_section(layout));
4047 
4048   // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
4049   // the .got section.
4050   Symbol* sym = this->global_offset_table_;
4051   if (sym != NULL)
4052     {
4053       uint64_t data_size = this->got_->current_data_size();
4054       symtab->get_sized_symbol<size>(sym)->set_symsize(data_size);
4055     }
4056 
4057   if (parameters->doing_static_link()
4058       && (this->plt_ == NULL || !this->plt_->has_irelative_section()))
4059     {
4060       // If linking statically, make sure that the __rela_iplt symbols
4061       // were defined if necessary, even if we didn't create a PLT.
4062       static const Define_symbol_in_segment syms[] =
4063 	{
4064 	  {
4065 	    "__rela_iplt_start",	// name
4066 	    elfcpp::PT_LOAD,		// segment_type
4067 	    elfcpp::PF_W,		// segment_flags_set
4068 	    elfcpp::PF(0),		// segment_flags_clear
4069 	    0,				// value
4070 	    0,				// size
4071 	    elfcpp::STT_NOTYPE,		// type
4072 	    elfcpp::STB_GLOBAL,		// binding
4073 	    elfcpp::STV_HIDDEN,		// visibility
4074 	    0,				// nonvis
4075 	    Symbol::SEGMENT_START,	// offset_from_base
4076 	    true			// only_if_ref
4077 	  },
4078 	  {
4079 	    "__rela_iplt_end",		// name
4080 	    elfcpp::PT_LOAD,		// segment_type
4081 	    elfcpp::PF_W,		// segment_flags_set
4082 	    elfcpp::PF(0),		// segment_flags_clear
4083 	    0,				// value
4084 	    0,				// size
4085 	    elfcpp::STT_NOTYPE,		// type
4086 	    elfcpp::STB_GLOBAL,		// binding
4087 	    elfcpp::STV_HIDDEN,		// visibility
4088 	    0,				// nonvis
4089 	    Symbol::SEGMENT_START,	// offset_from_base
4090 	    true			// only_if_ref
4091 	  }
4092 	};
4093 
4094       symtab->define_symbols(layout, 2, syms,
4095 			     layout->script_options()->saw_sections_clause());
4096     }
4097 }
4098 
4099 // Scan the relocs during a relocatable link.
4100 
4101 template<int size>
4102 void
scan_relocatable_relocs(Symbol_table * symtab,Layout * layout,Sized_relobj_file<size,true> * object,unsigned int data_shndx,unsigned int sh_type,const unsigned char * prelocs,size_t reloc_count,Output_section * output_section,bool needs_special_offset_handling,size_t local_symbol_count,const unsigned char * plocal_symbols,Relocatable_relocs * rr)4103 Target_s390<size>::scan_relocatable_relocs(
4104     Symbol_table* symtab,
4105     Layout* layout,
4106     Sized_relobj_file<size, true>* object,
4107     unsigned int data_shndx,
4108     unsigned int sh_type,
4109     const unsigned char* prelocs,
4110     size_t reloc_count,
4111     Output_section* output_section,
4112     bool needs_special_offset_handling,
4113     size_t local_symbol_count,
4114     const unsigned char* plocal_symbols,
4115     Relocatable_relocs* rr)
4116 {
4117   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, true>
4118       Classify_reloc;
4119   typedef gold::Default_scan_relocatable_relocs<Classify_reloc>
4120       Scan_relocatable_relocs;
4121 
4122   gold_assert(sh_type == elfcpp::SHT_RELA);
4123 
4124   gold::scan_relocatable_relocs<size, true, Scan_relocatable_relocs>(
4125     symtab,
4126     layout,
4127     object,
4128     data_shndx,
4129     prelocs,
4130     reloc_count,
4131     output_section,
4132     needs_special_offset_handling,
4133     local_symbol_count,
4134     plocal_symbols,
4135     rr);
4136 }
4137 
4138 // Scan the relocs for --emit-relocs.
4139 
4140 template<int size>
4141 void
emit_relocs_scan(Symbol_table * symtab,Layout * layout,Sized_relobj_file<size,true> * object,unsigned int data_shndx,unsigned int sh_type,const unsigned char * prelocs,size_t reloc_count,Output_section * output_section,bool needs_special_offset_handling,size_t local_symbol_count,const unsigned char * plocal_syms,Relocatable_relocs * rr)4142 Target_s390<size>::emit_relocs_scan(
4143     Symbol_table* symtab,
4144     Layout* layout,
4145     Sized_relobj_file<size, true>* object,
4146     unsigned int data_shndx,
4147     unsigned int sh_type,
4148     const unsigned char* prelocs,
4149     size_t reloc_count,
4150     Output_section* output_section,
4151     bool needs_special_offset_handling,
4152     size_t local_symbol_count,
4153     const unsigned char* plocal_syms,
4154     Relocatable_relocs* rr)
4155 {
4156   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, true>
4157       Classify_reloc;
4158   typedef gold::Default_emit_relocs_strategy<Classify_reloc>
4159       Emit_relocs_strategy;
4160 
4161   gold_assert(sh_type == elfcpp::SHT_RELA);
4162 
4163   gold::scan_relocatable_relocs<size, true, Emit_relocs_strategy>(
4164     symtab,
4165     layout,
4166     object,
4167     data_shndx,
4168     prelocs,
4169     reloc_count,
4170     output_section,
4171     needs_special_offset_handling,
4172     local_symbol_count,
4173     plocal_syms,
4174     rr);
4175 }
4176 
4177 // Relocate a section during a relocatable link.
4178 
4179 template<int size>
4180 void
relocate_relocs(const Relocate_info<size,true> * relinfo,unsigned int sh_type,const unsigned char * prelocs,size_t reloc_count,Output_section * output_section,typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,unsigned char * view,typename elfcpp::Elf_types<size>::Elf_Addr view_address,section_size_type view_size,unsigned char * reloc_view,section_size_type reloc_view_size)4181 Target_s390<size>::relocate_relocs(
4182     const Relocate_info<size, true>* relinfo,
4183     unsigned int sh_type,
4184     const unsigned char* prelocs,
4185     size_t reloc_count,
4186     Output_section* output_section,
4187     typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
4188     unsigned char* view,
4189     typename elfcpp::Elf_types<size>::Elf_Addr view_address,
4190     section_size_type view_size,
4191     unsigned char* reloc_view,
4192     section_size_type reloc_view_size)
4193 {
4194   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, true>
4195       Classify_reloc;
4196 
4197   gold_assert(sh_type == elfcpp::SHT_RELA);
4198 
4199   gold::relocate_relocs<size, true, Classify_reloc>(
4200     relinfo,
4201     prelocs,
4202     reloc_count,
4203     output_section,
4204     offset_in_output_section,
4205     view,
4206     view_address,
4207     view_size,
4208     reloc_view,
4209     reloc_view_size);
4210 }
4211 
4212 // Return the offset to use for the GOT_INDX'th got entry which is
4213 // for a local tls symbol specified by OBJECT, SYMNDX.
4214 template<int size>
4215 int64_t
do_tls_offset_for_local(const Relobj *,unsigned int,unsigned int) const4216 Target_s390<size>::do_tls_offset_for_local(
4217     const Relobj*,
4218     unsigned int,
4219     unsigned int) const
4220 {
4221   // The only way we can get called is when IEENT/GOTIE12/GOTIE20
4222   // couldn't be optimised to LE.
4223   Output_segment* tls_segment = layout_->tls_segment();
4224   return -tls_segment->memsz();
4225 }
4226 
4227 // Return the offset to use for the GOT_INDX'th got entry which is
4228 // for global tls symbol GSYM.
4229 template<int size>
4230 int64_t
do_tls_offset_for_global(Symbol *,unsigned int) const4231 Target_s390<size>::do_tls_offset_for_global(
4232     Symbol*,
4233     unsigned int) const
4234 {
4235   Output_segment* tls_segment = layout_->tls_segment();
4236   return -tls_segment->memsz();
4237 }
4238 
4239 // Return the value to use for a dynamic which requires special
4240 // treatment.  This is how we support equality comparisons of function
4241 // pointers across shared library boundaries, as described in the
4242 // processor specific ABI supplement.
4243 
4244 template<int size>
4245 uint64_t
do_dynsym_value(const Symbol * gsym) const4246 Target_s390<size>::do_dynsym_value(const Symbol* gsym) const
4247 {
4248   gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
4249   return this->plt_address_for_global(gsym);
4250 }
4251 
4252 // Return a string used to fill a code section with nops to take up
4253 // the specified length.
4254 
4255 template<int size>
4256 std::string
do_code_fill(section_size_type length) const4257 Target_s390<size>::do_code_fill(section_size_type length) const
4258 {
4259   if (length & 1)
4260     gold_warning(_("S/390 code fill of odd length requested"));
4261   return std::string(length, static_cast<char>(0x07));
4262 }
4263 
4264 // Return whether SYM should be treated as a call to a non-split
4265 // function.  We don't want that to be true of a larl instruction
4266 // that merely loads its address.
4267 
4268 template<int size>
4269 bool
do_is_call_to_non_split(const Symbol * sym,const unsigned char * preloc,const unsigned char * view,section_size_type view_size) const4270 Target_s390<size>::do_is_call_to_non_split(const Symbol* sym,
4271 					   const unsigned char* preloc,
4272 					   const unsigned char* view,
4273 					   section_size_type view_size) const
4274 {
4275   if (sym->type() != elfcpp::STT_FUNC)
4276     return false;
4277   typename Reloc_types<elfcpp::SHT_RELA, size, true>::Reloc reloc(preloc);
4278   typename elfcpp::Elf_types<size>::Elf_WXword r_info
4279     = reloc.get_r_info();
4280   unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
4281   section_offset_type offset = reloc.get_r_offset();
4282   switch (r_type)
4283     {
4284     // PLT refs always involve calling the function.
4285     case elfcpp::R_390_PLT12DBL:
4286     case elfcpp::R_390_PLT16DBL:
4287     case elfcpp::R_390_PLT24DBL:
4288     case elfcpp::R_390_PLT32:
4289     case elfcpp::R_390_PLT32DBL:
4290     case elfcpp::R_390_PLT64:
4291     case elfcpp::R_390_PLTOFF16:
4292     case elfcpp::R_390_PLTOFF32:
4293     case elfcpp::R_390_PLTOFF64:
4294     // Could be used for calls for -msmall-exec.
4295     case elfcpp::R_390_PC16DBL:
4296       return true;
4297 
4298     // Tricky case.  When used in a brasl, jg, and other branch instructions,
4299     // it's a call or a sibcall.  However, when used in larl, it only loads
4300     // the function's address - not a call.
4301     case elfcpp::R_390_PC32DBL:
4302       {
4303 	if (offset < 2
4304 	    || offset + 4 > static_cast<section_offset_type>(view_size))
4305 	  {
4306 	    // Should not happen.
4307 	    gold_error(_("instruction with PC32DBL not wholly within section"));
4308 	    return false;
4309 	  }
4310 
4311 	uint8_t op0 = view[offset-2];
4312 	uint8_t op1 = view[offset-1] & 0xf;
4313 
4314 	// LARL
4315 	if (op0 == 0xc0 && op1 == 0)
4316 	  return false;
4317 
4318 	// Otherwise, it's either a call instruction, a branch instruction
4319 	// (used as a sibcall), or a data manipulation instruction (which
4320 	// has no business being used on a function, and can be ignored).
4321         return true;
4322       }
4323 
4324     // Otherwise, it's probably not a call.
4325     default:
4326       return false;
4327     }
4328 }
4329 
4330 // Code sequences to match below.
4331 
4332 template<int size>
4333 const unsigned char
4334 Target_s390<size>::ss_code_bras_8[] = {
4335   0xa7, 0x15, 0x00, 0x06,		// bras %r1, .+0xc
4336 };
4337 
4338 template<int size>
4339 const unsigned char
4340 Target_s390<size>::ss_code_l_basr[] = {
4341   0x58, 0xe0, 0x10, 0x00,		// l %r14, 0(%r1)
4342   0x58, 0x10, 0x10, 0x04,		// l %r1, 4(%r1)
4343   0x0d, 0xee,				// basr %r14, %r14
4344 };
4345 
4346 template<int size>
4347 const unsigned char
4348 Target_s390<size>::ss_code_a_basr[] = {
4349   0x18, 0xe1,				// lr %r14, %r1
4350   0x5a, 0xe0, 0x10, 0x00,		// a %r14, 0(%r1)
4351   0x5a, 0x10, 0x10, 0x04,		// a %r1, 4(%r1)
4352   0x0d, 0xee,				// basr %r14, %r14
4353 };
4354 
4355 template<int size>
4356 const unsigned char
4357 Target_s390<size>::ss_code_larl[] = {
4358   0xc0, 0x10,				// larl %r1, ...
4359 };
4360 
4361 template<int size>
4362 const unsigned char
4363 Target_s390<size>::ss_code_brasl[] = {
4364   0xc0, 0xe5,				// brasl %r14, ...
4365 };
4366 
4367 template<int size>
4368 const unsigned char
4369 Target_s390<size>::ss_code_jg[] = {
4370   0xc0, 0xf4,				// jg ...
4371 };
4372 
4373 template<int size>
4374 const unsigned char
4375 Target_s390<size>::ss_code_jgl[] = {
4376   0xc0, 0x44,				// jgl ...
4377 };
4378 
4379 template<>
4380 bool
ss_match_st_r14(unsigned char * view,section_size_type view_size,section_offset_type * offset) const4381 Target_s390<32>::ss_match_st_r14(unsigned char* view,
4382 				 section_size_type view_size,
4383 				 section_offset_type *offset) const
4384 {
4385   static const unsigned char ss_code_st_r14[] = {
4386     0x50, 0xe0, 0xf0, 0x04,		// st %r14, 4(%r15)
4387   };
4388   if (!this->match_view_u(view, view_size, *offset, ss_code_st_r14,
4389 			  sizeof ss_code_st_r14))
4390     return false;
4391   *offset += sizeof ss_code_st_r14;
4392   return true;
4393 }
4394 
4395 template<>
4396 bool
ss_match_st_r14(unsigned char * view,section_size_type view_size,section_offset_type * offset) const4397 Target_s390<64>::ss_match_st_r14(unsigned char* view,
4398 				 section_size_type view_size,
4399 				 section_offset_type *offset) const
4400 {
4401   static const unsigned char ss_code_st_r14[] = {
4402     0xe3, 0xe0, 0xf0, 0x08, 0x00, 0x24	// stg %r14, 8(%r15)
4403   };
4404   if (!this->match_view_u(view, view_size, *offset, ss_code_st_r14,
4405 			  sizeof ss_code_st_r14))
4406     return false;
4407   *offset += sizeof ss_code_st_r14;
4408   return true;
4409 }
4410 
4411 template<>
4412 bool
ss_match_l_r14(unsigned char * view,section_size_type view_size,section_offset_type * offset) const4413 Target_s390<32>::ss_match_l_r14(unsigned char* view,
4414 				section_size_type view_size,
4415 				section_offset_type *offset) const
4416 {
4417   static const unsigned char ss_code_l_r14[] = {
4418     0x58, 0xe0, 0xf0, 0x04,		// l %r14, 4(%r15)
4419   };
4420   if (!this->match_view_u(view, view_size, *offset, ss_code_l_r14,
4421 			  sizeof ss_code_l_r14))
4422     return false;
4423   *offset += sizeof ss_code_l_r14;
4424   return true;
4425 }
4426 
4427 template<>
4428 bool
ss_match_l_r14(unsigned char * view,section_size_type view_size,section_offset_type * offset) const4429 Target_s390<64>::ss_match_l_r14(unsigned char* view,
4430 				section_size_type view_size,
4431 				section_offset_type *offset) const
4432 {
4433   static const unsigned char ss_code_l_r14[] = {
4434     0xe3, 0xe0, 0xf0, 0x08, 0x00, 0x04	// lg %r14, 8(%r15)
4435   };
4436   if (!this->match_view_u(view, view_size, *offset, ss_code_l_r14,
4437 			  sizeof ss_code_l_r14))
4438     return false;
4439   *offset += sizeof ss_code_l_r14;
4440   return true;
4441 }
4442 
4443 template<int size>
4444 bool
ss_match_mcount(unsigned char * view,section_size_type view_size,section_offset_type * offset) const4445 Target_s390<size>::ss_match_mcount(unsigned char* view,
4446 				   section_size_type view_size,
4447 				   section_offset_type *offset) const
4448 {
4449   // Match the mcount call sequence.
4450   section_offset_type myoff = *offset;
4451 
4452   // First, look for the store instruction saving %r14.
4453   if (!this->ss_match_st_r14(view, view_size, &myoff))
4454     return false;
4455 
4456   // Now, param load and the actual call.
4457   if (this->match_view_u(view, view_size, myoff, ss_code_larl,
4458 			 sizeof ss_code_larl))
4459     {
4460       myoff += sizeof ss_code_larl + 4;
4461 
4462       // After larl, expect a brasl.
4463       if (!this->match_view_u(view, view_size, myoff, ss_code_brasl,
4464 			      sizeof ss_code_brasl))
4465 	return false;
4466       myoff += sizeof ss_code_brasl + 4;
4467     }
4468   else if (size == 32 &&
4469 	   this->match_view_u(view, view_size, myoff, ss_code_bras_8,
4470 			      sizeof ss_code_bras_8))
4471     {
4472       // The bras skips over a block of 8 bytes, loading its address
4473       // to %r1.
4474       myoff += sizeof ss_code_bras_8 + 8;
4475 
4476       // Now, there are two sequences used for actual load and call,
4477       // absolute and PIC.
4478       if (this->match_view_u(view, view_size, myoff, ss_code_l_basr,
4479 			     sizeof ss_code_l_basr))
4480         myoff += sizeof ss_code_l_basr;
4481       else if (this->match_view_u(view, view_size, myoff, ss_code_a_basr,
4482 				  sizeof ss_code_a_basr))
4483         myoff += sizeof ss_code_a_basr;
4484       else
4485 	return false;
4486     }
4487   else
4488     return false;
4489 
4490   // Finally, a load bringing %r14 back.
4491   if (!this->ss_match_l_r14(view, view_size, &myoff))
4492     return false;
4493 
4494   // Found it.
4495   *offset = myoff;
4496   return true;
4497 }
4498 
4499 template<>
4500 bool
ss_match_ear(unsigned char * view,section_size_type view_size,section_offset_type * offset) const4501 Target_s390<32>::ss_match_ear(unsigned char* view,
4502 				section_size_type view_size,
4503 				section_offset_type *offset) const
4504 {
4505   static const unsigned char ss_code_ear[] = {
4506     0xb2, 0x4f, 0x00, 0x10,		// ear %r1, %a0
4507   };
4508   if (!this->match_view_u(view, view_size, *offset, ss_code_ear,
4509 			  sizeof ss_code_ear))
4510     return false;
4511   *offset += sizeof ss_code_ear;
4512   return true;
4513 }
4514 
4515 template<>
4516 bool
ss_match_ear(unsigned char * view,section_size_type view_size,section_offset_type * offset) const4517 Target_s390<64>::ss_match_ear(unsigned char* view,
4518 				section_size_type view_size,
4519 				section_offset_type *offset) const
4520 {
4521   static const unsigned char ss_code_ear[] = {
4522     0xb2, 0x4f, 0x00, 0x10,		// ear %r1, %a0
4523     0xeb, 0x11, 0x00, 0x20, 0x00, 0x0d,	// sllg %r1,%r1,32
4524     0xb2, 0x4f, 0x00, 0x11,		// ear %r1, %a1
4525   };
4526   if (!this->match_view_u(view, view_size, *offset, ss_code_ear,
4527 			  sizeof ss_code_ear))
4528     return false;
4529   *offset += sizeof ss_code_ear;
4530   return true;
4531 }
4532 
4533 template<>
4534 bool
ss_match_c(unsigned char * view,section_size_type view_size,section_offset_type * offset) const4535 Target_s390<32>::ss_match_c(unsigned char* view,
4536 				section_size_type view_size,
4537 				section_offset_type *offset) const
4538 {
4539   static const unsigned char ss_code_c[] = {
4540     0x59, 0xf0, 0x10, 0x20,		// c %r15, 0x20(%r1)
4541   };
4542   if (!this->match_view_u(view, view_size, *offset, ss_code_c,
4543 			  sizeof ss_code_c))
4544     return false;
4545   *offset += sizeof ss_code_c;
4546   return true;
4547 }
4548 
4549 template<>
4550 bool
ss_match_c(unsigned char * view,section_size_type view_size,section_offset_type * offset) const4551 Target_s390<64>::ss_match_c(unsigned char* view,
4552 				section_size_type view_size,
4553 				section_offset_type *offset) const
4554 {
4555   static const unsigned char ss_code_c[] = {
4556     0xe3, 0xf0, 0x10, 0x38, 0x00, 0x20,	// cg %r15, 0x38(%r1)
4557   };
4558   if (!this->match_view_u(view, view_size, *offset, ss_code_c,
4559 			  sizeof ss_code_c))
4560     return false;
4561   *offset += sizeof ss_code_c;
4562   return true;
4563 }
4564 
4565 template<>
4566 bool
ss_match_l(unsigned char * view,section_size_type view_size,section_offset_type * offset,int * guard_reg) const4567 Target_s390<32>::ss_match_l(unsigned char* view,
4568 			    section_size_type view_size,
4569 			    section_offset_type *offset,
4570 			    int *guard_reg) const
4571 {
4572   // l %guard_reg, 0x20(%r1)
4573   if (convert_to_section_size_type(*offset + 4) > view_size
4574       || view[*offset] != 0x58
4575       || (view[*offset + 1] & 0xf) != 0x0
4576       || view[*offset + 2] != 0x10
4577       || view[*offset + 3] != 0x20)
4578     return false;
4579   *offset += 4;
4580   *guard_reg = view[*offset + 1] >> 4 & 0xf;
4581   return true;
4582 }
4583 
4584 template<>
4585 bool
ss_match_l(unsigned char * view,section_size_type view_size,section_offset_type * offset,int * guard_reg) const4586 Target_s390<64>::ss_match_l(unsigned char* view,
4587 			    section_size_type view_size,
4588 			    section_offset_type *offset,
4589 			    int *guard_reg) const
4590 {
4591   // lg %guard_reg, 0x38(%r1)
4592   if (convert_to_section_size_type(*offset + 6) > view_size
4593       || view[*offset] != 0xe3
4594       || (view[*offset + 1] & 0xf) != 0x0
4595       || view[*offset + 2] != 0x10
4596       || view[*offset + 3] != 0x38
4597       || view[*offset + 4] != 0x00
4598       || view[*offset + 5] != 0x04)
4599     return false;
4600   *offset += 6;
4601   *guard_reg = view[*offset + 1] >> 4 & 0xf;
4602   return true;
4603 }
4604 
4605 template<int size>
4606 bool
ss_match_ahi(unsigned char * view,section_size_type view_size,section_offset_type * offset,int guard_reg,uint32_t * arg) const4607 Target_s390<size>::ss_match_ahi(unsigned char* view,
4608 				section_size_type view_size,
4609 				section_offset_type *offset,
4610 				int guard_reg,
4611 				uint32_t *arg) const
4612 {
4613   int op = size == 32 ? 0xa : 0xb;
4614   // a[g]hi %guard_reg, <arg>
4615   if (convert_to_section_size_type(*offset + 4) > view_size
4616       || view[*offset] != 0xa7
4617       || view[*offset + 1] != (guard_reg << 4 | op)
4618       // Disallow negative size.
4619       || view[*offset + 2] & 0x80)
4620     return false;
4621   *arg = elfcpp::Swap<16, true>::readval(view + *offset + 2);
4622   *offset += 4;
4623   return true;
4624 }
4625 
4626 template<int size>
4627 bool
ss_match_alfi(unsigned char * view,section_size_type view_size,section_offset_type * offset,int guard_reg,uint32_t * arg) const4628 Target_s390<size>::ss_match_alfi(unsigned char* view,
4629 				 section_size_type view_size,
4630 				 section_offset_type *offset,
4631 				 int guard_reg,
4632 				 uint32_t *arg) const
4633 {
4634   int op = size == 32 ? 0xb : 0xa;
4635   // al[g]fi %guard_reg, <arg>
4636   if (convert_to_section_size_type(*offset + 6) > view_size
4637       || view[*offset] != 0xc2
4638       || view[*offset + 1] != (guard_reg << 4 | op))
4639     return false;
4640   *arg = elfcpp::Swap<32, true>::readval(view + *offset + 2);
4641   *offset += 6;
4642   return true;
4643 }
4644 
4645 template<>
4646 bool
ss_match_cr(unsigned char * view,section_size_type view_size,section_offset_type * offset,int guard_reg) const4647 Target_s390<32>::ss_match_cr(unsigned char* view,
4648 			     section_size_type view_size,
4649 			     section_offset_type *offset,
4650 			     int guard_reg) const
4651 {
4652   // cr %r15, %guard_reg
4653   if (convert_to_section_size_type(*offset + 2) > view_size
4654       || view[*offset] != 0x19
4655       || view[*offset + 1] != (0xf0 | guard_reg))
4656     return false;
4657   *offset += 2;
4658   return true;
4659 }
4660 
4661 template<>
4662 bool
ss_match_cr(unsigned char * view,section_size_type view_size,section_offset_type * offset,int guard_reg) const4663 Target_s390<64>::ss_match_cr(unsigned char* view,
4664 			     section_size_type view_size,
4665 			     section_offset_type *offset,
4666 			     int guard_reg) const
4667 {
4668   // cgr %r15, %guard_reg
4669   if (convert_to_section_size_type(*offset + 4) > view_size
4670       || view[*offset] != 0xb9
4671       || view[*offset + 1] != 0x20
4672       || view[*offset + 2] != 0x00
4673       || view[*offset + 3] != (0xf0 | guard_reg))
4674     return false;
4675   *offset += 4;
4676   return true;
4677 }
4678 
4679 
4680 // FNOFFSET in section SHNDX in OBJECT is the start of a function
4681 // compiled with -fsplit-stack.  The function calls non-split-stack
4682 // code.  We have to change the function so that it always ensures
4683 // that it has enough stack space to run some random function.
4684 
4685 template<int size>
4686 void
do_calls_non_split(Relobj * object,unsigned int shndx,section_offset_type fnoffset,section_size_type,const unsigned char * prelocs,size_t reloc_count,unsigned char * view,section_size_type view_size,std::string *,std::string *) const4687 Target_s390<size>::do_calls_non_split(Relobj* object, unsigned int shndx,
4688 				      section_offset_type fnoffset,
4689 				      section_size_type,
4690 				      const unsigned char *prelocs,
4691 				      size_t reloc_count,
4692 				      unsigned char* view,
4693 				      section_size_type view_size,
4694 				      std::string*,
4695 				      std::string*) const
4696 {
4697   // true if there's a conditional call to __morestack in the function,
4698   // false if there's an unconditional one.
4699   bool conditional = false;
4700   // Offset of the byte after the compare insn, if conditional.
4701   section_offset_type cmpend = 0;
4702   // Type and immediate offset of the add instruction that adds frame size
4703   // to guard.
4704   enum {
4705     SS_ADD_NONE,
4706     SS_ADD_AHI,
4707     SS_ADD_ALFI,
4708   } fsadd_type = SS_ADD_NONE;
4709   section_offset_type fsadd_offset = 0;
4710   uint32_t fsadd_frame_size = 0;
4711   // Register used for loading guard.  Usually r1, but can also be r0 or r2-r5.
4712   int guard_reg;
4713   // Offset of the conditional jump.
4714   section_offset_type jump_offset = 0;
4715   // Section view and offset of param block.
4716   section_offset_type param_offset = 0;
4717   unsigned char *param_view = 0;
4718   section_size_type param_view_size = 0;
4719   // Current position in function.
4720   section_offset_type curoffset = fnoffset;
4721   // And the position of split-stack prologue.
4722   section_offset_type ssoffset;
4723   // Frame size.
4724   typename elfcpp::Elf_types<size>::Elf_Addr frame_size;
4725   // Relocation parsing.
4726   typedef typename Reloc_types<elfcpp::SHT_RELA, size, true>::Reloc Reltype;
4727   const int reloc_size = Reloc_types<elfcpp::SHT_RELA, size, true>::reloc_size;
4728   const unsigned char *pr = prelocs;
4729 
4730   // If the function was compiled with -pg, the profiling code may come before
4731   // the split-stack prologue.  Skip it.
4732 
4733   this->ss_match_mcount(view, view_size, &curoffset);
4734   ssoffset = curoffset;
4735 
4736   // First, figure out if there's a conditional call by looking for the
4737   // extract-tp, add, cmp sequence.
4738 
4739   if (this->ss_match_ear(view, view_size, &curoffset))
4740     {
4741       // Found extract-tp, now look for an add and compare.
4742       conditional = true;
4743       if (this->ss_match_c(view, view_size, &curoffset))
4744 	{
4745 	  // Found a direct compare of stack pointer with the guard,
4746 	  // we're done here.
4747 	}
4748       else if (this->ss_match_l(view, view_size, &curoffset, &guard_reg))
4749 	{
4750 	  // Found a load of guard to register, look for an add and compare.
4751           if (this->ss_match_ahi(view, view_size, &curoffset, guard_reg,
4752 				 &fsadd_frame_size))
4753 	    {
4754 	      fsadd_type = SS_ADD_AHI;
4755 	      fsadd_offset = curoffset - 2;
4756 	    }
4757 	  else if (this->ss_match_alfi(view, view_size, &curoffset, guard_reg,
4758 				       &fsadd_frame_size))
4759 	    {
4760 	      fsadd_type = SS_ADD_ALFI;
4761 	      fsadd_offset = curoffset - 4;
4762 	    }
4763 	  else
4764             {
4765 	      goto bad;
4766             }
4767 	  // Now, there has to be a compare.
4768           if (!this->ss_match_cr(view, view_size, &curoffset, guard_reg))
4769 	    goto bad;
4770 	}
4771       else
4772         {
4773 	  goto bad;
4774         }
4775       cmpend = curoffset;
4776     }
4777 
4778   // Second, look for the call.
4779   if (!this->match_view_u(view, view_size, curoffset, ss_code_larl,
4780 			  sizeof ss_code_larl))
4781     goto bad;
4782   curoffset += sizeof ss_code_larl;
4783 
4784   // Find out larl's operand.  It should be a local symbol in .rodata
4785   // section.
4786   for (size_t i = 0; i < reloc_count; ++i, pr += reloc_size)
4787     {
4788       Reltype reloc(pr);
4789       if (static_cast<section_offset_type>(reloc.get_r_offset())
4790           == curoffset)
4791         {
4792           typename elfcpp::Elf_types<size>::Elf_WXword r_info
4793             = reloc.get_r_info();
4794           unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
4795           unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
4796           if (r_type != elfcpp::R_390_PC32DBL)
4797             goto bad;
4798           if (r_sym >= object->local_symbol_count())
4799             goto bad;
4800           Sized_relobj_file<size, true> *object_sized =
4801             static_cast<Sized_relobj_file<size, true> *>(object);
4802           const Symbol_value<size>* sym = object_sized->local_symbol(r_sym);
4803           bool param_shndx_ordinary;
4804           const unsigned int param_shndx =
4805             sym->input_shndx(&param_shndx_ordinary);
4806           if (!param_shndx_ordinary)
4807             goto bad;
4808           param_offset = sym->input_value() + reloc.get_r_addend() - 2
4809                          - object->output_section(param_shndx)->address()
4810                          - object->output_section_offset(param_shndx);
4811           param_view = object->get_output_view(param_shndx,
4812                                                   &param_view_size);
4813           break;
4814         }
4815     }
4816 
4817   if (!param_view)
4818     goto bad;
4819 
4820   curoffset += 4;
4821 
4822   // Now, there has to be a jump to __morestack.
4823   jump_offset = curoffset;
4824 
4825   if (this->match_view_u(view, view_size, curoffset,
4826                        conditional ? ss_code_jgl : ss_code_jg,
4827                        sizeof ss_code_jg))
4828     curoffset += sizeof ss_code_jg;
4829   else
4830     goto bad;
4831 
4832   curoffset += 4;
4833 
4834   // Read the frame size.
4835   if (convert_to_section_size_type(param_offset + size / 8) > param_view_size)
4836     goto bad;
4837   frame_size = elfcpp::Swap<size, true>::readval(param_view + param_offset);
4838 
4839   // Sanity check.
4840   if (fsadd_type != SS_ADD_NONE && fsadd_frame_size != frame_size)
4841     goto bad;
4842 
4843   // Bump the frame size.
4844   frame_size += parameters->options().split_stack_adjust_size();
4845 
4846   // Store it to the param block.
4847   elfcpp::Swap<size, true>::writeval(param_view + param_offset, frame_size);
4848 
4849   if (!conditional)
4850     {
4851       // If the call was already unconditional, we're done.
4852     }
4853   else if (frame_size <= 0xffffffff && fsadd_type == SS_ADD_ALFI)
4854     {
4855       // Using alfi to add the frame size, and it still fits.  Adjust it.
4856       elfcpp::Swap_unaligned<32, true>::writeval(view + fsadd_offset,
4857 						 frame_size);
4858     }
4859   else
4860     {
4861       // We were either relying on the backoff area, or used ahi to load
4862       // frame size.  This won't fly, as our new frame size is too large.
4863       // Convert the sequence to unconditional by nopping out the comparison,
4864       // and rewiring the jump.
4865       this->set_view_to_nop(view, view_size, ssoffset, cmpend - ssoffset);
4866 
4867       // The jump is jgl, we'll mutate it to jg.
4868       view[jump_offset+1] = 0xf4;
4869     }
4870 
4871   return;
4872 
4873 bad:
4874   if (!object->has_no_split_stack())
4875       object->error(_("failed to match split-stack sequence at "
4876 		      "section %u offset %0zx"),
4877 		    shndx, static_cast<size_t>(fnoffset));
4878 }
4879 
4880 // Relocate section data.
4881 
4882 template<int size>
4883 void
relocate_section(const Relocate_info<size,true> * relinfo,unsigned int sh_type,const unsigned char * prelocs,size_t reloc_count,Output_section * output_section,bool needs_special_offset_handling,unsigned char * view,typename elfcpp::Elf_types<size>::Elf_Addr address,section_size_type view_size,const Reloc_symbol_changes * reloc_symbol_changes)4884 Target_s390<size>::relocate_section(
4885     const Relocate_info<size, true>* relinfo,
4886     unsigned int sh_type,
4887     const unsigned char* prelocs,
4888     size_t reloc_count,
4889     Output_section* output_section,
4890     bool needs_special_offset_handling,
4891     unsigned char* view,
4892     typename elfcpp::Elf_types<size>::Elf_Addr address,
4893     section_size_type view_size,
4894     const Reloc_symbol_changes* reloc_symbol_changes)
4895 {
4896   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, true>
4897       Classify_reloc;
4898 
4899   gold_assert(sh_type == elfcpp::SHT_RELA);
4900 
4901   gold::relocate_section<size, true, Target_s390<size>, Relocate,
4902 			 gold::Default_comdat_behavior, Classify_reloc>(
4903     relinfo,
4904     this,
4905     prelocs,
4906     reloc_count,
4907     output_section,
4908     needs_special_offset_handling,
4909     view,
4910     address,
4911     view_size,
4912     reloc_symbol_changes);
4913 }
4914 
4915 // Apply an incremental relocation.  Incremental relocations always refer
4916 // to global symbols.
4917 
4918 template<int size>
4919 void
apply_relocation(const Relocate_info<size,true> * relinfo,typename elfcpp::Elf_types<size>::Elf_Addr r_offset,unsigned int r_type,typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,const Symbol * gsym,unsigned char * view,typename elfcpp::Elf_types<size>::Elf_Addr address,section_size_type view_size)4920 Target_s390<size>::apply_relocation(
4921     const Relocate_info<size, true>* relinfo,
4922     typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
4923     unsigned int r_type,
4924     typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
4925     const Symbol* gsym,
4926     unsigned char* view,
4927     typename elfcpp::Elf_types<size>::Elf_Addr address,
4928     section_size_type view_size)
4929 {
4930   gold::apply_relocation<size, true, Target_s390<size>,
4931 			 typename Target_s390<size>::Relocate>(
4932     relinfo,
4933     this,
4934     r_offset,
4935     r_type,
4936     r_addend,
4937     gsym,
4938     view,
4939     address,
4940     view_size);
4941 }
4942 
4943 // The selector for s390 object files.
4944 
4945 template<int size>
4946 class Target_selector_s390 : public Target_selector
4947 {
4948 public:
Target_selector_s390()4949   Target_selector_s390()
4950     : Target_selector(elfcpp::EM_S390, size, true,
4951 		      (size == 64 ? "elf64-s390" : "elf32-s390"),
4952 		      (size == 64 ? "elf64_s390" : "elf32_s390"))
4953   { }
4954 
4955   virtual Target*
do_instantiate_target()4956   do_instantiate_target()
4957   { return new Target_s390<size>(); }
4958 };
4959 
4960 Target_selector_s390<32> target_selector_s390;
4961 Target_selector_s390<64> target_selector_s390x;
4962 
4963 } // End anonymous namespace.
4964