xref: /openbsd/gnu/gcc/gcc/config/rs6000/linux64.h (revision 404b540a)
1 /* Definitions of target machine for GNU compiler,
2    for 64 bit PowerPC linux.
3    Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006
4    Free Software Foundation, Inc.
5 
6    This file is part of GCC.
7 
8    GCC is free software; you can redistribute it and/or modify it
9    under the terms of the GNU General Public License as published
10    by the Free Software Foundation; either version 2, or (at your
11    option) any later version.
12 
13    GCC is distributed in the hope that it will be useful, but WITHOUT
14    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
16    License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with GCC; see the file COPYING.  If not, write to the
20    Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
21    MA 02110-1301, USA.  */
22 
23 #ifndef RS6000_BI_ARCH
24 
25 #undef	DEFAULT_ABI
26 #define	DEFAULT_ABI ABI_AIX
27 
28 #undef	TARGET_64BIT
29 #define	TARGET_64BIT 1
30 
31 #define	DEFAULT_ARCH64_P 1
32 #define	RS6000_BI_ARCH_P 0
33 
34 #else
35 
36 #define	DEFAULT_ARCH64_P (TARGET_DEFAULT & MASK_64BIT)
37 #define	RS6000_BI_ARCH_P 1
38 
39 #endif
40 
41 #ifdef IN_LIBGCC2
42 #undef TARGET_64BIT
43 #ifdef __powerpc64__
44 #define TARGET_64BIT 1
45 #else
46 #define TARGET_64BIT 0
47 #endif
48 #endif
49 
50 #undef	TARGET_AIX
51 #define	TARGET_AIX TARGET_64BIT
52 
53 #ifdef HAVE_LD_NO_DOT_SYMS
54 /* New ABI uses a local sym for the function entry point.  */
55 extern int dot_symbols;
56 #undef DOT_SYMBOLS
57 #define DOT_SYMBOLS dot_symbols
58 #endif
59 
60 #undef  PROCESSOR_DEFAULT
61 #define PROCESSOR_DEFAULT PROCESSOR_POWER4
62 #undef  PROCESSOR_DEFAULT64
63 #define PROCESSOR_DEFAULT64 PROCESSOR_POWER4
64 
65 /* We don't need to generate entries in .fixup, except when
66    -mrelocatable or -mrelocatable-lib is given.  */
67 #undef RELOCATABLE_NEEDS_FIXUP
68 #define RELOCATABLE_NEEDS_FIXUP \
69   (target_flags & target_flags_explicit & MASK_RELOCATABLE)
70 
71 #undef	RS6000_ABI_NAME
72 #define	RS6000_ABI_NAME "linux"
73 
74 #define INVALID_64BIT "-m%s not supported in this configuration"
75 #define INVALID_32BIT INVALID_64BIT
76 
77 #undef	SUBSUBTARGET_OVERRIDE_OPTIONS
78 #define	SUBSUBTARGET_OVERRIDE_OPTIONS				\
79   do								\
80     {								\
81       if (!rs6000_explicit_options.alignment)			\
82 	rs6000_alignment_flags = MASK_ALIGN_NATURAL;		\
83       if (TARGET_64BIT)						\
84 	{							\
85 	  if (DEFAULT_ABI != ABI_AIX)				\
86 	    {							\
87 	      rs6000_current_abi = ABI_AIX;			\
88 	      error (INVALID_64BIT, "call");			\
89 	    }							\
90 	  dot_symbols = !strcmp (rs6000_abi_name, "aixdesc");	\
91 	  if (target_flags & MASK_RELOCATABLE)			\
92 	    {							\
93 	      target_flags &= ~MASK_RELOCATABLE;		\
94 	      error (INVALID_64BIT, "relocatable");		\
95 	    }							\
96 	  if (target_flags & MASK_EABI)				\
97 	    {							\
98 	      target_flags &= ~MASK_EABI;			\
99 	      error (INVALID_64BIT, "eabi");			\
100 	    }							\
101 	  if (target_flags & MASK_PROTOTYPE)			\
102 	    {							\
103 	      target_flags &= ~MASK_PROTOTYPE;			\
104 	      error (INVALID_64BIT, "prototype");		\
105 	    }							\
106 	  if ((target_flags & MASK_POWERPC64) == 0)		\
107 	    {							\
108 	      target_flags |= MASK_POWERPC64;			\
109 	      error ("-m64 requires a PowerPC64 cpu");		\
110 	    }							\
111 	}							\
112       else							\
113 	{							\
114 	  if (!RS6000_BI_ARCH_P)				\
115 	    error (INVALID_32BIT, "32");			\
116 	  if (TARGET_PROFILE_KERNEL)				\
117 	    {							\
118 	      target_flags &= ~MASK_PROFILE_KERNEL;		\
119 	      error (INVALID_32BIT, "profile-kernel");		\
120 	    }							\
121 	}							\
122     }								\
123   while (0)
124 
125 #ifdef	RS6000_BI_ARCH
126 
127 #undef	OVERRIDE_OPTIONS
128 #define	OVERRIDE_OPTIONS \
129   rs6000_override_options (((TARGET_DEFAULT ^ target_flags) & MASK_64BIT) \
130 			   ? (char *) 0 : TARGET_CPU_DEFAULT)
131 
132 #endif
133 
134 #undef	ASM_DEFAULT_SPEC
135 #undef	ASM_SPEC
136 #undef	LINK_OS_LINUX_SPEC
137 
138 #ifndef	RS6000_BI_ARCH
139 #define	ASM_DEFAULT_SPEC "-mppc64"
140 #define	ASM_SPEC	 "%(asm_spec64) %(asm_spec_common)"
141 #define	LINK_OS_LINUX_SPEC "%(link_os_linux_spec64)"
142 #else
143 #if DEFAULT_ARCH64_P
144 #define	ASM_DEFAULT_SPEC "-mppc%{!m32:64}"
145 #define	ASM_SPEC	 "%{m32:%(asm_spec32)}%{!m32:%(asm_spec64)} %(asm_spec_common)"
146 #define	LINK_OS_LINUX_SPEC "%{m32:%(link_os_linux_spec32)}%{!m32:%(link_os_linux_spec64)}"
147 #else
148 #define	ASM_DEFAULT_SPEC "-mppc%{m64:64}"
149 #define	ASM_SPEC	 "%{!m64:%(asm_spec32)}%{m64:%(asm_spec64)} %(asm_spec_common)"
150 #define	LINK_OS_LINUX_SPEC "%{!m64:%(link_os_linux_spec32)}%{m64:%(link_os_linux_spec64)}"
151 #endif
152 #endif
153 
154 #define ASM_SPEC32 "-a32 %{n} %{T} %{Ym,*} %{Yd,*} \
155 %{mrelocatable} %{mrelocatable-lib} %{fpic:-K PIC} %{fPIC:-K PIC} \
156 %{memb} %{!memb: %{msdata: -memb} %{msdata=eabi: -memb}} \
157 %{!mlittle: %{!mlittle-endian: %{!mbig: %{!mbig-endian: \
158     %{mcall-freebsd: -mbig} \
159     %{mcall-i960-old: -mlittle} \
160     %{mcall-linux: -mbig} \
161     %{mcall-gnu: -mbig} \
162     %{mcall-netbsd: -mbig} \
163 }}}}"
164 
165 #define ASM_SPEC64 "-a64"
166 
167 #define ASM_SPEC_COMMON "%(asm_cpu) \
168 %{.s: %{mregnames} %{mno-regnames}} %{.S: %{mregnames} %{mno-regnames}} \
169 %{v:-V} %{Qy:} %{!Qn:-Qy} %{Wa,*:%*} \
170 %{mlittle} %{mlittle-endian} %{mbig} %{mbig-endian}"
171 
172 #undef	SUBSUBTARGET_EXTRA_SPECS
173 #define SUBSUBTARGET_EXTRA_SPECS \
174   { "asm_spec_common",		ASM_SPEC_COMMON },			\
175   { "asm_spec32",		ASM_SPEC32 },				\
176   { "asm_spec64",		ASM_SPEC64 },				\
177   { "link_os_linux_spec32",	LINK_OS_LINUX_SPEC32 },			\
178   { "link_os_linux_spec64",	LINK_OS_LINUX_SPEC64 },
179 
180 #undef	MULTILIB_DEFAULTS
181 #if DEFAULT_ARCH64_P
182 #define MULTILIB_DEFAULTS { "m64" }
183 #else
184 #define MULTILIB_DEFAULTS { "m32" }
185 #endif
186 
187 #ifndef RS6000_BI_ARCH
188 
189 /* 64-bit PowerPC Linux is always big-endian.  */
190 #undef	TARGET_LITTLE_ENDIAN
191 #define TARGET_LITTLE_ENDIAN	0
192 
193 /* 64-bit PowerPC Linux always has a TOC.  */
194 #undef  TARGET_TOC
195 #define	TARGET_TOC		1
196 
197 /* Some things from sysv4.h we don't do when 64 bit.  */
198 #undef	TARGET_RELOCATABLE
199 #define	TARGET_RELOCATABLE	0
200 #undef	TARGET_EABI
201 #define	TARGET_EABI		0
202 #undef	TARGET_PROTOTYPE
203 #define	TARGET_PROTOTYPE	0
204 #undef RELOCATABLE_NEEDS_FIXUP
205 #define RELOCATABLE_NEEDS_FIXUP 0
206 
207 #endif
208 
209 /* We use glibc _mcount for profiling.  */
210 #define NO_PROFILE_COUNTERS 1
211 #define PROFILE_HOOK(LABEL) \
212   do { if (TARGET_64BIT) output_profile_hook (LABEL); } while (0)
213 
214 /* PowerPC64 Linux word-aligns FP doubles when -malign-power is given.  */
215 #undef  ADJUST_FIELD_ALIGN
216 #define ADJUST_FIELD_ALIGN(FIELD, COMPUTED) \
217   ((TARGET_ALTIVEC && TREE_CODE (TREE_TYPE (FIELD)) == VECTOR_TYPE)	\
218    ? 128								\
219    : (TARGET_64BIT							\
220       && TARGET_ALIGN_NATURAL == 0					\
221       && TYPE_MODE (TREE_CODE (TREE_TYPE (FIELD)) == ARRAY_TYPE		\
222 		    ? get_inner_array_type (FIELD)			\
223 		    : TREE_TYPE (FIELD)) == DFmode)			\
224    ? MIN ((COMPUTED), 32)						\
225    : (COMPUTED))
226 
227 /* PowerPC64 Linux increases natural record alignment to doubleword if
228    the first field is an FP double, only if in power alignment mode.  */
229 #undef  ROUND_TYPE_ALIGN
230 #define ROUND_TYPE_ALIGN(STRUCT, COMPUTED, SPECIFIED)			\
231   ((TARGET_64BIT							\
232     && (TREE_CODE (STRUCT) == RECORD_TYPE				\
233 	|| TREE_CODE (STRUCT) == UNION_TYPE				\
234 	|| TREE_CODE (STRUCT) == QUAL_UNION_TYPE)			\
235     && TARGET_ALIGN_NATURAL == 0)					\
236    ? rs6000_special_round_type_align (STRUCT, COMPUTED, SPECIFIED)	\
237    : MAX ((COMPUTED), (SPECIFIED)))
238 
239 /* Use the default for compiling target libs.  */
240 #ifdef IN_TARGET_LIBS
241 #undef TARGET_ALIGN_NATURAL
242 #define TARGET_ALIGN_NATURAL 1
243 #endif
244 
245 /* Indicate that jump tables go in the text section.  */
246 #undef  JUMP_TABLES_IN_TEXT_SECTION
247 #define JUMP_TABLES_IN_TEXT_SECTION TARGET_64BIT
248 
249 /* The linux ppc64 ABI isn't explicit on whether aggregates smaller
250    than a doubleword should be padded upward or downward.  You could
251    reasonably assume that they follow the normal rules for structure
252    layout treating the parameter area as any other block of memory,
253    then map the reg param area to registers.  i.e. pad upward.
254    Setting both of the following defines results in this behavior.
255    Setting just the first one will result in aggregates that fit in a
256    doubleword being padded downward, and others being padded upward.
257    Not a bad idea as this results in struct { int x; } being passed
258    the same way as an int.  */
259 #define AGGREGATE_PADDING_FIXED TARGET_64BIT
260 #define AGGREGATES_PAD_UPWARD_ALWAYS 0
261 
262 /* Specify padding for the last element of a block move between
263    registers and memory.  FIRST is nonzero if this is the only
264    element.  */
265 #define BLOCK_REG_PADDING(MODE, TYPE, FIRST) \
266   (!(FIRST) ? upward : FUNCTION_ARG_PADDING (MODE, TYPE))
267 
268 /* __throw will restore its own return address to be the same as the
269    return address of the function that the throw is being made to.
270    This is unfortunate, because we want to check the original
271    return address to see if we need to restore the TOC.
272    So we have to squirrel it away with this.  */
273 #define SETUP_FRAME_ADDRESSES() \
274   do { if (TARGET_64BIT) rs6000_aix_emit_builtin_unwind_init (); } while (0)
275 
276 /* Override svr4.h  */
277 #undef MD_EXEC_PREFIX
278 #undef MD_STARTFILE_PREFIX
279 
280 /* Linux doesn't support saving and restoring 64-bit regs in a 32-bit
281    process.  */
282 #define OS_MISSING_POWERPC64 !TARGET_64BIT
283 
284 /* glibc has float and long double forms of math functions.  */
285 #undef  TARGET_C99_FUNCTIONS
286 #define TARGET_C99_FUNCTIONS (OPTION_GLIBC)
287 
288 #undef  TARGET_OS_CPP_BUILTINS
289 #define TARGET_OS_CPP_BUILTINS()			\
290   do							\
291     {							\
292       if (TARGET_64BIT)					\
293 	{						\
294 	  builtin_define ("__PPC__");			\
295 	  builtin_define ("__PPC64__");			\
296 	  builtin_define ("__powerpc__");		\
297 	  builtin_define ("__powerpc64__");		\
298 	  builtin_assert ("cpu=powerpc64");		\
299 	  builtin_assert ("machine=powerpc64");		\
300 	}						\
301       else						\
302 	{						\
303 	  builtin_define_std ("PPC");			\
304 	  builtin_define_std ("powerpc");		\
305 	  builtin_assert ("cpu=powerpc");		\
306 	  builtin_assert ("machine=powerpc");		\
307 	  TARGET_OS_SYSV_CPP_BUILTINS ();		\
308 	}						\
309     }							\
310   while (0)
311 
312 #undef  CPP_OS_DEFAULT_SPEC
313 #define CPP_OS_DEFAULT_SPEC "%(cpp_os_linux)"
314 
315 /* The GNU C++ standard library currently requires _GNU_SOURCE being
316    defined on glibc-based systems. This temporary hack accomplishes this,
317    it should go away as soon as libstdc++-v3 has a real fix.  */
318 #undef  CPLUSPLUS_CPP_SPEC
319 #define CPLUSPLUS_CPP_SPEC "-D_GNU_SOURCE %(cpp)"
320 
321 #undef  LINK_SHLIB_SPEC
322 #define LINK_SHLIB_SPEC "%{shared:-shared} %{!shared: %{static:-static}}"
323 
324 #undef  LIB_DEFAULT_SPEC
325 #define LIB_DEFAULT_SPEC "%(lib_linux)"
326 
327 #undef  STARTFILE_DEFAULT_SPEC
328 #define STARTFILE_DEFAULT_SPEC "%(startfile_linux)"
329 
330 #undef	ENDFILE_DEFAULT_SPEC
331 #define ENDFILE_DEFAULT_SPEC "%(endfile_linux)"
332 
333 #undef	LINK_START_DEFAULT_SPEC
334 #define LINK_START_DEFAULT_SPEC "%(link_start_linux)"
335 
336 #undef	LINK_OS_DEFAULT_SPEC
337 #define LINK_OS_DEFAULT_SPEC "%(link_os_linux)"
338 
339 #define GLIBC_DYNAMIC_LINKER32 "/lib/ld.so.1"
340 #define GLIBC_DYNAMIC_LINKER64 "/lib64/ld64.so.1"
341 #define UCLIBC_DYNAMIC_LINKER32 "/lib/ld-uClibc.so.0"
342 #define UCLIBC_DYNAMIC_LINKER64 "/lib/ld64-uClibc.so.0"
343 #if UCLIBC_DEFAULT
344 #define CHOOSE_DYNAMIC_LINKER(G, U) "%{mglibc:%{muclibc:%e-mglibc and -muclibc used together}" G ";:" U "}"
345 #else
346 #define CHOOSE_DYNAMIC_LINKER(G, U) "%{muclibc:%{mglibc:%e-mglibc and -muclibc used together}" U ";:" G "}"
347 #endif
348 #define LINUX_DYNAMIC_LINKER32 \
349   CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER32, UCLIBC_DYNAMIC_LINKER32)
350 #define LINUX_DYNAMIC_LINKER64 \
351   CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER64, UCLIBC_DYNAMIC_LINKER64)
352 
353 
354 #define LINK_OS_LINUX_SPEC32 "-m elf32ppclinux %{!shared: %{!static: \
355   %{rdynamic:-export-dynamic} \
356   %{!dynamic-linker:-dynamic-linker " LINUX_DYNAMIC_LINKER32 "}}}"
357 
358 #define LINK_OS_LINUX_SPEC64 "-m elf64ppc %{!shared: %{!static: \
359   %{rdynamic:-export-dynamic} \
360   %{!dynamic-linker:-dynamic-linker " LINUX_DYNAMIC_LINKER64 "}}}"
361 
362 #undef  TOC_SECTION_ASM_OP
363 #define TOC_SECTION_ASM_OP \
364   (TARGET_64BIT						\
365    ? "\t.section\t\".toc\",\"aw\""			\
366    : "\t.section\t\".got\",\"aw\"")
367 
368 #undef  MINIMAL_TOC_SECTION_ASM_OP
369 #define MINIMAL_TOC_SECTION_ASM_OP \
370   (TARGET_64BIT						\
371    ? "\t.section\t\".toc1\",\"aw\""			\
372    : ((TARGET_RELOCATABLE || flag_pic)			\
373       ? "\t.section\t\".got2\",\"aw\""			\
374       : "\t.section\t\".got1\",\"aw\""))
375 
376 #undef  TARGET_VERSION
377 #define TARGET_VERSION fprintf (stderr, " (PowerPC64 GNU/Linux)");
378 
379 /* Must be at least as big as our pointer type.  */
380 #undef	SIZE_TYPE
381 #define	SIZE_TYPE (TARGET_64BIT ? "long unsigned int" : "unsigned int")
382 
383 #undef	PTRDIFF_TYPE
384 #define	PTRDIFF_TYPE (TARGET_64BIT ? "long int" : "int")
385 
386 #undef	WCHAR_TYPE
387 #define	WCHAR_TYPE (TARGET_64BIT ? "int" : "long int")
388 #undef  WCHAR_TYPE_SIZE
389 #define WCHAR_TYPE_SIZE 32
390 
391 /* Override rs6000.h definition.  */
392 #undef  ASM_APP_ON
393 #define ASM_APP_ON "#APP\n"
394 
395 /* Override rs6000.h definition.  */
396 #undef  ASM_APP_OFF
397 #define ASM_APP_OFF "#NO_APP\n"
398 
399 /* PowerPC no-op instruction.  */
400 #undef  RS6000_CALL_GLUE
401 #define RS6000_CALL_GLUE (TARGET_64BIT ? "nop" : "cror 31,31,31")
402 
403 #undef  RS6000_MCOUNT
404 #define RS6000_MCOUNT "_mcount"
405 
406 #ifdef __powerpc64__
407 /* _init and _fini functions are built from bits spread across many
408    object files, each potentially with a different TOC pointer.  For
409    that reason, place a nop after the call so that the linker can
410    restore the TOC pointer if a TOC adjusting call stub is needed.  */
411 #if DOT_SYMBOLS
412 #define CRT_CALL_STATIC_FUNCTION(SECTION_OP, FUNC)	\
413   asm (SECTION_OP "\n"					\
414 "	bl ." #FUNC "\n"				\
415 "	nop\n"						\
416 "	.previous");
417 #else
418 #define CRT_CALL_STATIC_FUNCTION(SECTION_OP, FUNC)	\
419   asm (SECTION_OP "\n"					\
420 "	bl " #FUNC "\n"					\
421 "	nop\n"						\
422 "	.previous");
423 #endif
424 #endif
425 
426 /* FP save and restore routines.  */
427 #undef  SAVE_FP_PREFIX
428 #define SAVE_FP_PREFIX (TARGET_64BIT ? "._savef" : "_savefpr_")
429 #undef  SAVE_FP_SUFFIX
430 #define SAVE_FP_SUFFIX (TARGET_64BIT ? "" : "_l")
431 #undef  RESTORE_FP_PREFIX
432 #define RESTORE_FP_PREFIX (TARGET_64BIT ? "._restf" : "_restfpr_")
433 #undef  RESTORE_FP_SUFFIX
434 #define RESTORE_FP_SUFFIX (TARGET_64BIT ? "" : "_l")
435 
436 /* Dwarf2 debugging.  */
437 #undef  PREFERRED_DEBUGGING_TYPE
438 #define PREFERRED_DEBUGGING_TYPE DWARF2_DEBUG
439 
440 /* This is how to declare the size of a function.  */
441 #undef	ASM_DECLARE_FUNCTION_SIZE
442 #define	ASM_DECLARE_FUNCTION_SIZE(FILE, FNAME, DECL)			\
443   do									\
444     {									\
445       if (!flag_inhibit_size_directive)					\
446 	{								\
447 	  fputs ("\t.size\t", (FILE));					\
448 	  if (TARGET_64BIT && DOT_SYMBOLS)				\
449 	    putc ('.', (FILE));						\
450 	  assemble_name ((FILE), (FNAME));				\
451 	  fputs (",.-", (FILE));					\
452 	  rs6000_output_function_entry (FILE, FNAME);			\
453 	  putc ('\n', (FILE));						\
454 	}								\
455     }									\
456   while (0)
457 
458 /* Return nonzero if this entry is to be written into the constant
459    pool in a special way.  We do so if this is a SYMBOL_REF, LABEL_REF
460    or a CONST containing one of them.  If -mfp-in-toc (the default),
461    we also do this for floating-point constants.  We actually can only
462    do this if the FP formats of the target and host machines are the
463    same, but we can't check that since not every file that uses
464    GO_IF_LEGITIMATE_ADDRESS_P includes real.h.  We also do this when
465    we can write the entry into the TOC and the entry is not larger
466    than a TOC entry.  */
467 
468 #undef  ASM_OUTPUT_SPECIAL_POOL_ENTRY_P
469 #define ASM_OUTPUT_SPECIAL_POOL_ENTRY_P(X, MODE)			\
470   (TARGET_TOC								\
471    && (GET_CODE (X) == SYMBOL_REF					\
472        || (GET_CODE (X) == CONST && GET_CODE (XEXP (X, 0)) == PLUS	\
473 	   && GET_CODE (XEXP (XEXP (X, 0), 0)) == SYMBOL_REF)		\
474        || GET_CODE (X) == LABEL_REF					\
475        || (GET_CODE (X) == CONST_INT 					\
476 	   && GET_MODE_BITSIZE (MODE) <= GET_MODE_BITSIZE (Pmode))	\
477        || (GET_CODE (X) == CONST_DOUBLE					\
478 	   && ((TARGET_64BIT						\
479 		&& (TARGET_POWERPC64					\
480 		    || TARGET_MINIMAL_TOC				\
481 		    || (SCALAR_FLOAT_MODE_P (GET_MODE (X))		\
482 			&& ! TARGET_NO_FP_IN_TOC)))			\
483 	       || (!TARGET_64BIT					\
484 		   && !TARGET_NO_FP_IN_TOC				\
485 		   && !TARGET_RELOCATABLE				\
486 		   && SCALAR_FLOAT_MODE_P (GET_MODE (X))		\
487 		   && BITS_PER_WORD == HOST_BITS_PER_INT)))))
488 
489 /* Select a format to encode pointers in exception handling data.  CODE
490    is 0 for data, 1 for code labels, 2 for function pointers.  GLOBAL is
491    true if the symbol may be affected by dynamic relocations.  */
492 #undef	ASM_PREFERRED_EH_DATA_FORMAT
493 #define	ASM_PREFERRED_EH_DATA_FORMAT(CODE, GLOBAL) \
494   ((TARGET_64BIT || flag_pic || TARGET_RELOCATABLE)			\
495    ? (((GLOBAL) ? DW_EH_PE_indirect : 0) | DW_EH_PE_pcrel		\
496       | (TARGET_64BIT ? DW_EH_PE_udata8 : DW_EH_PE_sdata4))		\
497    : DW_EH_PE_absptr)
498 
499 /* For backward compatibility, we must continue to use the AIX
500    structure return convention.  */
501 #undef DRAFT_V4_STRUCT_RET
502 #define DRAFT_V4_STRUCT_RET (!TARGET_64BIT)
503 
504 #define TARGET_ASM_FILE_END rs6000_elf_end_indicate_exec_stack
505 
506 #define TARGET_POSIX_IO
507 
508 #define LINK_GCC_C_SEQUENCE_SPEC \
509   "%{static:--start-group} %G %L %{static:--end-group}%{!static:%G}"
510 
511 /* Use --as-needed -lgcc_s for eh support.  */
512 #ifdef HAVE_LD_AS_NEEDED
513 #define USE_LD_AS_NEEDED 1
514 #endif
515 
516 #define MD_UNWIND_SUPPORT "config/rs6000/linux-unwind.h"
517 
518 #ifdef TARGET_LIBC_PROVIDES_SSP
519 /* ppc32 glibc provides __stack_chk_guard in -0x7008(2),
520    ppc64 glibc provides it at -0x7010(13).  */
521 #define TARGET_THREAD_SSP_OFFSET	(TARGET_64BIT ? -0x7010 : -0x7008)
522 #endif
523 
524 #define POWERPC_LINUX
525 
526 /* ppc{32,64} linux has 128-bit long double support in glibc 2.4 and later.  */
527 #ifdef TARGET_DEFAULT_LONG_DOUBLE_128
528 #define RS6000_DEFAULT_LONG_DOUBLE_SIZE 128
529 #endif
530