1 /* Definitions of target machine for GNU compiler, 2 for IBM RS/6000 POWER running AIX. 3 Copyright (C) 2000-2020 Free Software Foundation, Inc. 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify it 8 under the terms of the GNU General Public License as published 9 by the Free Software Foundation; either version 3, or (at your 10 option) any later version. 11 12 GCC is distributed in the hope that it will be useful, but WITHOUT 13 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 14 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public 15 License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GCC; see the file COPYING3. If not see 19 <http://www.gnu.org/licenses/>. */ 20 21 /* Yes! We are AIX! */ 22 #define DEFAULT_ABI ABI_AIX 23 #undef TARGET_AIX 24 #define TARGET_AIX 1 25 26 /* System headers are not C++-aware. */ 27 #define SYSTEM_IMPLICIT_EXTERN_C 1 28 29 /* Linux64.h wants to redefine TARGET_AIX based on -m64, but it can't be used 30 in the #if conditional in options-default.h, so provide another macro. */ 31 #undef TARGET_AIX_OS 32 #define TARGET_AIX_OS 1 33 34 /* AIX always has a TOC. */ 35 #define TARGET_HAS_TOC 1 36 #define FIXED_R2 1 37 38 /* AIX allows r13 to be used in 32-bit mode. */ 39 #define FIXED_R13 0 40 41 /* 32-bit and 64-bit AIX stack boundary is 128. */ 42 #undef STACK_BOUNDARY 43 #define STACK_BOUNDARY 128 44 45 /* Offset within stack frame to start allocating local variables at. 46 If FRAME_GROWS_DOWNWARD, this is the offset to the END of the 47 first local allocated. Otherwise, it is the offset to the BEGINNING 48 of the first local allocated. 49 50 On the RS/6000, the frame pointer is the same as the stack pointer, 51 except for dynamic allocations. So we start after the fixed area and 52 outgoing parameter area. 53 54 If the function uses dynamic stack space (CALLS_ALLOCA is set), that 55 space needs to be aligned to STACK_BOUNDARY, i.e. the sum of the 56 sizes of the fixed area and the parameter area must be a multiple of 57 STACK_BOUNDARY. */ 58 59 #undef RS6000_STARTING_FRAME_OFFSET 60 #define RS6000_STARTING_FRAME_OFFSET \ 61 (cfun->calls_alloca \ 62 ? RS6000_ALIGN (crtl->outgoing_args_size + RS6000_SAVE_AREA, 16) \ 63 : (RS6000_ALIGN (crtl->outgoing_args_size, 16) + RS6000_SAVE_AREA)) 64 65 /* Offset from the stack pointer register to an item dynamically 66 allocated on the stack, e.g., by `alloca'. 67 68 The default value for this macro is `STACK_POINTER_OFFSET' plus the 69 length of the outgoing arguments. The default is correct for most 70 machines. See `function.c' for details. 71 72 This value must be a multiple of STACK_BOUNDARY (hard coded in 73 `emit-rtl.c'). */ 74 #undef STACK_DYNAMIC_OFFSET 75 #define STACK_DYNAMIC_OFFSET(FUNDECL) \ 76 RS6000_ALIGN (crtl->outgoing_args_size.to_constant () \ 77 + STACK_POINTER_OFFSET, 16) 78 79 #undef TARGET_IEEEQUAD 80 #define TARGET_IEEEQUAD 0 81 82 #undef TARGET_IEEEQUAD_DEFAULT 83 #define TARGET_IEEEQUAD_DEFAULT 0 84 85 /* The AIX linker will discard static constructors in object files before 86 collect has a chance to see them, so scan the object files directly. */ 87 #define COLLECT_EXPORT_LIST 88 89 /* On AIX, initialisers specified with -binitfini are called in breadth-first 90 order. 91 e.g. if a.out depends on lib1.so, the init function for a.out is called before 92 the init function for lib1.so. 93 94 To ensure global C++ constructors in linked libraries are run before global 95 C++ constructors from the current module, there is additional symbol scanning 96 logic in collect2. 97 98 The global initialiser/finaliser functions are named __GLOBAL_AIXI_{libname} 99 and __GLOBAL_AIXD_{libname} and are exported from each shared library. 100 101 collect2 will detect these symbols when they exist in shared libraries that 102 the current program is being linked against. All such initiliser functions 103 will be called prior to the constructors of the current program, and 104 finaliser functions called after destructors. 105 106 Reference counting generated by collect2 will ensure that constructors are 107 only invoked once in the case of multiple dependencies on a library. 108 109 -binitfini is still used in parallel to this solution. 110 This handles the case where a library is loaded through dlopen(), and also 111 handles the option -blazy. 112 */ 113 #define COLLECT_SHARED_INIT_FUNC(STREAM, FUNC) \ 114 fprintf ((STREAM), "void %s() {\n\t%s();\n}\n", aix_shared_initname, (FUNC)) 115 #define COLLECT_SHARED_FINI_FUNC(STREAM, FUNC) \ 116 fprintf ((STREAM), "void %s() {\n\t%s();\n}\n", aix_shared_fininame, (FUNC)) 117 118 #if HAVE_AS_REF 119 /* Issue assembly directives that create a reference to the given DWARF table 120 identifier label from the current function section. This is defined to 121 ensure we drag frame tables associated with needed function bodies in 122 a link with garbage collection activated. */ 123 #define ASM_OUTPUT_DWARF_TABLE_REF rs6000_aix_asm_output_dwarf_table_ref 124 #endif 125 126 /* This is the only version of nm that collect2 can work with. */ 127 #define REAL_NM_FILE_NAME "/usr/ucb/nm" 128 129 #define USER_LABEL_PREFIX "" 130 131 /* Don't turn -B into -L if the argument specifies a relative file name. */ 132 #define RELATIVE_PREFIX_NOT_LINKDIR 133 134 /* Because of the above, we must have gcc search itself to find libgcc.a. */ 135 #define LINK_LIBGCC_SPECIAL_1 136 137 /* Names to predefine in the preprocessor for this target machine. */ 138 #define TARGET_OS_AIX_CPP_BUILTINS() \ 139 do \ 140 { \ 141 builtin_define ("_IBMR2"); \ 142 builtin_define ("_POWER"); \ 143 builtin_define ("__unix__"); \ 144 builtin_define ("_AIX"); \ 145 builtin_define ("_AIX32"); \ 146 builtin_define ("_AIX41"); \ 147 builtin_define ("_LONG_LONG"); \ 148 if (TARGET_LONG_DOUBLE_128) \ 149 builtin_define ("__LONGDOUBLE128"); \ 150 builtin_assert ("system=unix"); \ 151 builtin_assert ("system=aix"); \ 152 if (TARGET_64BIT) \ 153 { \ 154 builtin_define ("__PPC__"); \ 155 builtin_define ("__PPC64__"); \ 156 builtin_define ("__powerpc__"); \ 157 builtin_define ("__powerpc64__"); \ 158 builtin_assert ("cpu=powerpc64"); \ 159 builtin_assert ("machine=powerpc64"); \ 160 } \ 161 else \ 162 { \ 163 builtin_define ("__PPC__"); \ 164 builtin_define ("__powerpc__"); \ 165 builtin_assert ("cpu=powerpc"); \ 166 builtin_assert ("machine=powerpc"); \ 167 } \ 168 } \ 169 while (0) 170 171 /* Define appropriate architecture macros for preprocessor depending on 172 target switches. */ 173 174 #define CPP_SPEC "%{posix: -D_POSIX_SOURCE}\ 175 %{ansi: -D_ANSI_C_SOURCE}" 176 177 #define CC1_SPEC "%(cc1_cpu)" 178 179 #undef ASM_DEFAULT_SPEC 180 #define ASM_DEFAULT_SPEC "" 181 182 /* Tell the assembler to assume that all undefined names are external. 183 184 Don't do this until the fixed IBM assembler is more generally available. 185 When this becomes permanently defined, the ASM_OUTPUT_EXTERNAL, 186 ASM_OUTPUT_EXTERNAL_LIBCALL, and RS6000_OUTPUT_BASENAME macros will no 187 longer be needed. Also, the extern declaration of mcount in 188 rs6000_xcoff_file_start will no longer be needed. */ 189 190 /* #define ASM_SPEC "-u %(asm_cpu)" */ 191 192 /* Default location of syscalls.exp under AIX */ 193 #define LINK_SYSCALLS_SPEC "-bI:%R/lib/syscalls.exp" 194 195 /* Default location of libg.exp under AIX */ 196 #define LINK_LIBG_SPEC "-bexport:%R/usr/lib/libg.exp" 197 198 /* Define the options for the binder: Start text at 512, align all segments 199 to 512 bytes, and warn if there is text relocation. 200 201 The -bhalt:4 option supposedly changes the level at which ld will abort, 202 but it also suppresses warnings about multiply defined symbols and is 203 used by the AIX cc command. So we use it here. 204 205 -bnodelcsect undoes a poor choice of default relating to multiply-defined 206 csects. See AIX documentation for more information about this. 207 208 -bM:SRE tells the linker that the output file is Shared REusable. Note 209 that to actually build a shared library you will also need to specify an 210 export list with the -Wl,-bE option. */ 211 212 #define LINK_SPEC "-T512 -H512 %{!r:-btextro} -bhalt:4 -bnodelcsect\ 213 %{static:-bnso %(link_syscalls) } \ 214 %{!shared:%{g*: %(link_libg) }} %{shared:-bM:SRE}" 215 216 /* Profiled library versions are used by linking with special directories. */ 217 #define LIB_SPEC "%{pg:-L%R/lib/profiled -L%R/usr/lib/profiled}\ 218 %{p:-L%R/lib/profiled -L%R/usr/lib/profiled} %{!shared:%{g*:-lg}} -lc" 219 220 /* Static linking with shared libstdc++ requires libsupc++ as well. */ 221 #define LIBSTDCXX_STATIC "supc++" 222 223 /* This now supports a natural alignment mode. */ 224 /* AIX word-aligns FP doubles but doubleword-aligns 64-bit ints. */ 225 #define ADJUST_FIELD_ALIGN(FIELD, TYPE, COMPUTED) \ 226 ((TARGET_ALIGN_NATURAL == 0 \ 227 && TYPE_MODE (strip_array_types (TYPE)) == DFmode) \ 228 ? MIN ((COMPUTED), 32) \ 229 : (COMPUTED)) 230 231 /* AIX increases natural record alignment to doubleword if the first 232 field is an FP double while the FP fields remain word aligned. */ 233 #define ROUND_TYPE_ALIGN(STRUCT, COMPUTED, SPECIFIED) \ 234 ((TREE_CODE (STRUCT) == RECORD_TYPE \ 235 || TREE_CODE (STRUCT) == UNION_TYPE \ 236 || TREE_CODE (STRUCT) == QUAL_UNION_TYPE) \ 237 && TARGET_ALIGN_NATURAL == 0 \ 238 ? rs6000_special_round_type_align (STRUCT, COMPUTED, SPECIFIED) \ 239 : MAX ((COMPUTED), (SPECIFIED))) 240 241 /* The AIX ABI isn't explicit on whether aggregates smaller than a 242 word/doubleword should be padded upward or downward. One could 243 reasonably assume that they follow the normal rules for structure 244 layout treating the parameter area as any other block of memory, 245 then map the reg param area to registers, i.e., pad upward, which 246 is the way IBM Compilers for AIX behave. 247 Setting both of the following defines results in this behavior. */ 248 #define AGGREGATE_PADDING_FIXED 1 249 #define AGGREGATES_PAD_UPWARD_ALWAYS 1 250 251 /* Specify padding for the last element of a block move between 252 registers and memory. FIRST is nonzero if this is the only 253 element. */ 254 #define BLOCK_REG_PADDING(MODE, TYPE, FIRST) \ 255 (!(FIRST) ? PAD_UPWARD : targetm.calls.function_arg_padding (MODE, TYPE)) 256 257 /* Indicate that jump tables go in the text section. */ 258 259 #define JUMP_TABLES_IN_TEXT_SECTION 1 260 261 /* Define any extra SPECS that the compiler needs to generate. */ 262 #undef SUBTARGET_EXTRA_SPECS 263 #define SUBTARGET_EXTRA_SPECS \ 264 { "link_syscalls", LINK_SYSCALLS_SPEC }, \ 265 { "link_libg", LINK_LIBG_SPEC } 266 267 #define PROFILE_HOOK(LABEL) output_profile_hook (LABEL) 268 269 /* No version of AIX fully supports AltiVec or 64-bit instructions in 270 32-bit mode. */ 271 #define OS_MISSING_POWERPC64 1 272 #define OS_MISSING_ALTIVEC 1 273 274 /* WINT_TYPE */ 275 #define WINT_TYPE "int" 276 277 /* Static stack checking is supported by means of probes. */ 278 #define STACK_CHECK_STATIC_BUILTIN 1 279 280 /* Use standard DWARF numbering for DWARF debugging information. */ 281 #define RS6000_USE_DWARF_NUMBERING 282 283