sysdeps/powerpc/powerpc64/sysdep.h

   1 /* Assembly macros for 64-bit PowerPC.
   2    Copyright (C) 2002-2019 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <sysdeps/powerpc/sysdep.h>
  20
  21 #ifdef __ASSEMBLER__
  22
  23 /* Stack frame offsets.  */
  24 #define FRAME_BACKCHAIN         0
  25 #define FRAME_CR_SAVE           8
  26 #define FRAME_LR_SAVE           16
  27 #if _CALL_ELF != 2
  28 #define FRAME_MIN_SIZE          112
  29 #define FRAME_MIN_SIZE_PARM     112
  30 #define FRAME_TOC_SAVE          40
  31 #define FRAME_PARM_SAVE         48
  32 #else
  33 #define FRAME_MIN_SIZE          32
  34 #define FRAME_MIN_SIZE_PARM     96
  35 #define FRAME_TOC_SAVE          24
  36 #define FRAME_PARM_SAVE         32
  37 #endif
  38
  39 /* Support macros for CALL_MCOUNT.  */
  40         .macro SAVE_ARG NARG
  41         .if \NARG
  42         SAVE_ARG \NARG-1
  43         std     2+\NARG,-FRAME_MIN_SIZE_PARM+FRAME_PARM_SAVE-8+8*(\NARG)(1)
  44         .endif
  45         .endm
  46
  47         .macro REST_ARG NARG
  48         .if \NARG
  49         REST_ARG \NARG-1
  50         ld      2+\NARG,FRAME_PARM_SAVE-8+8*(\NARG)(1)
  51         .endif
  52         .endm
  53
  54         .macro CFI_SAVE_ARG NARG
  55         .if \NARG
  56         CFI_SAVE_ARG \NARG-1
  57         cfi_offset(2+\NARG,-FRAME_MIN_SIZE_PARM+FRAME_PARM_SAVE-8+8*(\NARG))
  58         .endif
  59         .endm
  60
  61         .macro CFI_REST_ARG NARG
  62         .if \NARG
  63         CFI_REST_ARG \NARG-1
  64         cfi_restore(2+\NARG)
  65         .endif
  66         .endm
  67
  68 /* If compiled for profiling, call `_mcount' at the start of each function.
  69    see ppc-mcount.S for more details.  */
  70         .macro CALL_MCOUNT NARG
  71 #ifdef  PROF
  72         mflr    r0
  73         SAVE_ARG \NARG
  74         std     r0,FRAME_LR_SAVE(r1)
  75         stdu    r1,-FRAME_MIN_SIZE_PARM(r1)
  76         cfi_adjust_cfa_offset(FRAME_MIN_SIZE_PARM)
  77         cfi_offset(lr,FRAME_LR_SAVE)
  78         CFI_SAVE_ARG \NARG
  79         bl      JUMPTARGET (_mcount)
  80 #ifndef SHARED
  81         nop
  82 #endif
  83         ld      r0,FRAME_MIN_SIZE_PARM+FRAME_LR_SAVE(r1)
  84         REST_ARG \NARG
  85         mtlr    r0
  86         addi    r1,r1,FRAME_MIN_SIZE_PARM
  87         cfi_adjust_cfa_offset(-FRAME_MIN_SIZE_PARM)
  88         cfi_restore(lr)
  89         CFI_REST_ARG \NARG
  90 #endif
  91         .endm
  92
  93 #if _CALL_ELF != 2
  94
  95 /* Macro to prepare for calling via a function pointer.  */
  96         .macro PPC64_LOAD_FUNCPTR PTR
  97         ld      r12,0(\PTR)
  98         ld      r2,8(\PTR)
  99         mtctr   r12
 100         ld      r11,16(\PTR)
 101         .endm
 102
 103 #ifdef USE_PPC64_OVERLAPPING_OPD
 104 # define OPD_ENT(name)  .quad BODY_LABEL (name), .TOC.@tocbase
 105 #else
 106 # define OPD_ENT(name)  .quad BODY_LABEL (name), .TOC.@tocbase, 0
 107 #endif
 108
 109 #define ENTRY_1(name)                           \
 110         .type BODY_LABEL(name),@function;       \
 111         .globl name;                            \
 112         .section ".opd","aw";                   \
 113         .p2align 3;FUNC_LABEL(name):            \
 114         OPD_ENT (name);                         \
 115         .previous
 116
 117 #define FUNC_LABEL(X) X
 118 #define BODY_LABEL(X) .LY##X
 119 #define ENTRY_2(name)                           \
 120         .type name,@function;                   \
 121         ENTRY_1(name)
 122 #define END_2(name)                             \
 123         .size name,.-BODY_LABEL(name);          \
 124         .size BODY_LABEL(name),.-BODY_LABEL(name)
 125 #define LOCALENTRY(name)
 126
 127 #else /* _CALL_ELF == 2 */
 128
 129 /* Macro to prepare for calling via a function pointer.  */
 130         .macro PPC64_LOAD_FUNCPTR PTR
 131         mr      r12,\PTR
 132         mtctr   r12
 133         .endm
 134
 135 #define FUNC_LABEL(X) X
 136 #define BODY_LABEL(X) X
 137 #define ENTRY_2(name)                           \
 138         .globl name;                            \
 139         .type name,@function
 140 #define END_2(name)                             \
 141         .size name,.-name
 142 #define LOCALENTRY(name)                        \
 143 1:      addis   r2,r12,.TOC.-1b@ha;             \
 144         addi    r2,r2,.TOC.-1b@l;               \
 145         .localentry name,.-name
 146
 147 #endif /* _CALL_ELF */
 148
 149         .macro NOPS NARG
 150         .if \NARG
 151         NOPS \NARG-1
 152         nop
 153         .endif
 154         .endm
 155
 156         .macro ENTRY_3 name, alignp2=2, nopwords=0
 157         .text
 158         ENTRY_2(\name)
 159         .p2align \alignp2
 160         NOPS \nopwords
 161 BODY_LABEL(\name):
 162         .endm
 163
 164 /* Use ENTRY_TOCLESS for functions that make no use of r2 and
 165    guarantee r2 is unchanged on exit.  Any function that has @toc or
 166    @got relocs uses r2.  Functions that call other functions via the
 167    PLT use r2.  Use ENTRY for functions that may use or change r2.
 168    The first argument is the function name.
 169    The optional second argument specifies alignment of the function's
 170    code, as the logarithm base two of the byte alignment.  For
 171    example, a value of four aligns to a sixteen byte boundary.
 172    The optional third argument specifies the number of NOPs to emit
 173    before the start of the function's code.   */
 174 #ifndef PROF
 175 #define ENTRY_TOCLESS(name, ...)                \
 176         ENTRY_3 name, ## __VA_ARGS__;           \
 177         cfi_startproc
 178
 179 #define ENTRY(name, ...)                        \
 180         ENTRY_TOCLESS(name, ## __VA_ARGS__);    \
 181         LOCALENTRY(name)
 182 #else
 183 /* The call to _mcount is potentially via the plt, so profiling code
 184    is never free of an r2 use.  */
 185 #define ENTRY_TOCLESS(name, ...)                \
 186         ENTRY_3 name, ## __VA_ARGS__;           \
 187         cfi_startproc;                          \
 188         LOCALENTRY(name)
 189
 190 #define ENTRY(name, ...)                        \
 191         ENTRY_TOCLESS(name, ## __VA_ARGS__)
 192 #endif
 193
 194 /* Local labels stripped out by the linker.  */
 195 #undef L
 196 #define L(x) .L##x
 197
 198 #define tostring(s) #s
 199 #define stringify(s) tostring(s)
 200 #define XGLUE(a,b) a##b
 201 #define GLUE(a,b) XGLUE(a,b)
 202 #define LT_LABEL(name) GLUE(.LT,name)
 203 #define LT_LABELSUFFIX(name,suffix) GLUE(GLUE(.LT,name),suffix)
 204
 205 /* Support Traceback tables */
 206 #define TB_ASM                  0x000c000000000000
 207 #define TB_GLOBALLINK           0x0000800000000000
 208 #define TB_IS_EPROL             0x0000400000000000
 209 #define TB_HAS_TBOFF            0x0000200000000000
 210 #define TB_INT_PROC             0x0000100000000000
 211 #define TB_HAS_CTL              0x0000080000000000
 212 #define TB_TOCLESS              0x0000040000000000
 213 #define TB_FP_PRESENT           0x0000020000000000
 214 #define TB_LOG_ABORT            0x0000010000000000
 215 #define TB_INT_HANDL            0x0000008000000000
 216 #define TB_NAME_PRESENT         0x0000004000000000
 217 #define TB_USES_ALLOCA          0x0000002000000000
 218 #define TB_SAVES_CR             0x0000000200000000
 219 #define TB_SAVES_LR             0x0000000100000000
 220 #define TB_STORES_BC            0x0000000080000000
 221 #define TB_FIXUP                0x0000000040000000
 222 #define TB_FP_SAVED(fprs)       (((fprs) & 0x3f) << 24)
 223 #define TB_GPR_SAVED(gprs)      (((fprs) & 0x3f) << 16)
 224 #define TB_FIXEDPARMS(parms)    (((parms) & 0xff) << 8)
 225 #define TB_FLOATPARMS(parms)    (((parms) & 0x7f) << 1)
 226 #define TB_PARMSONSTK           0x0000000000000001
 227
 228 #define PPC_HIGHER(v)           (((v) >> 32) & 0xffff)
 229 #define TB_DEFAULT              TB_ASM | TB_HAS_TBOFF | TB_NAME_PRESENT
 230
 231 #define TRACEBACK(name) \
 232 LT_LABEL(name): ; \
 233         .long   0 ; \
 234         .quad   TB_DEFAULT ; \
 235         .long   LT_LABEL(name)-BODY_LABEL(name) ; \
 236         .short  LT_LABELSUFFIX(name,_name_end)-LT_LABELSUFFIX(name,_name_start) ; \
 237 LT_LABELSUFFIX(name,_name_start): ;\
 238         .ascii  stringify(name) ; \
 239 LT_LABELSUFFIX(name,_name_end): ; \
 240         .p2align 2
 241
 242 #define TRACEBACK_MASK(name,mask) \
 243 LT_LABEL(name): ; \
 244         .long   0 ; \
 245         .quad   TB_DEFAULT | mask ; \
 246         .long   LT_LABEL(name)-BODY_LABEL(name) ; \
 247         .short  LT_LABELSUFFIX(name,_name_end)-LT_LABELSUFFIX(name,_name_start) ; \
 248 LT_LABELSUFFIX(name,_name_start): ;\
 249         .ascii  stringify(name) ; \
 250 LT_LABELSUFFIX(name,_name_end): ; \
 251         .p2align 2
 252
 253 /* END generates Traceback tables */
 254 #undef  END
 255 #define END(name) \
 256   cfi_endproc;                  \
 257   TRACEBACK(name);              \
 258   END_2(name)
 259
 260 /* This form supports more informative traceback tables */
 261 #define END_GEN_TB(name,mask)   \
 262   cfi_endproc;                  \
 263   TRACEBACK_MASK(name,mask);    \
 264   END_2(name)
 265
 266 #define DO_CALL(syscall) \
 267     li 0,syscall; \
 268     sc
 269
 270 /* ppc64 is always PIC */
 271 #undef JUMPTARGET
 272 #define JUMPTARGET(name) FUNC_LABEL(name)
 273
 274 #define PSEUDO(name, syscall_name, args) \
 275   .section ".text";                             \
 276   ENTRY (name);                                 \
 277   DO_CALL (SYS_ify (syscall_name))
 278
 279 #ifdef SHARED
 280 #define TAIL_CALL_SYSCALL_ERROR \
 281     b JUMPTARGET(__syscall_error)
 282 #else
 283 /* Static version might be linked into a large app with a toc exceeding
 284    64k.  We can't put a toc adjusting stub on a plain branch, so can't
 285    tail call __syscall_error.  */
 286 #define TAIL_CALL_SYSCALL_ERROR \
 287     .ifdef .Local_syscall_error; \
 288     b .Local_syscall_error; \
 289     .else; \
 290 .Local_syscall_error: \
 291     mflr 0; \
 292     std 0,FRAME_LR_SAVE(1); \
 293     stdu 1,-FRAME_MIN_SIZE(1); \
 294     cfi_adjust_cfa_offset(FRAME_MIN_SIZE); \
 295     cfi_offset(lr,FRAME_LR_SAVE); \
 296     bl JUMPTARGET(__syscall_error); \
 297     nop; \
 298     ld 0,FRAME_MIN_SIZE+FRAME_LR_SAVE(1); \
 299     addi 1,1,FRAME_MIN_SIZE; \
 300     cfi_adjust_cfa_offset(-FRAME_MIN_SIZE); \
 301     mtlr 0; \
 302     cfi_restore(lr); \
 303     blr; \
 304     .endif
 305 #endif
 306
 307 #define PSEUDO_RET \
 308     bnslr+; \
 309     TAIL_CALL_SYSCALL_ERROR
 310
 311 #define ret PSEUDO_RET
 312
 313 #undef  PSEUDO_END
 314 #define PSEUDO_END(name) \
 315   END (name)
 316
 317 #define PSEUDO_NOERRNO(name, syscall_name, args) \
 318   .section ".text";                                     \
 319   ENTRY (name);                                         \
 320   DO_CALL (SYS_ify (syscall_name))
 321
 322 #define PSEUDO_RET_NOERRNO \
 323     blr
 324
 325 #define ret_NOERRNO PSEUDO_RET_NOERRNO
 326
 327 #undef  PSEUDO_END_NOERRNO
 328 #define PSEUDO_END_NOERRNO(name) \
 329   END (name)
 330
 331 #define PSEUDO_ERRVAL(name, syscall_name, args) \
 332   .section ".text";                                     \
 333   ENTRY (name);                                         \
 334   DO_CALL (SYS_ify (syscall_name))
 335
 336 #define PSEUDO_RET_ERRVAL \
 337     blr
 338
 339 #define ret_ERRVAL PSEUDO_RET_ERRVAL
 340
 341 #undef  PSEUDO_END_ERRVAL
 342 #define PSEUDO_END_ERRVAL(name) \
 343   END (name)
 344
 345 #else /* !__ASSEMBLER__ */
 346
 347 #if _CALL_ELF != 2
 348
 349 #define PPC64_LOAD_FUNCPTR(ptr) \
 350         "ld     12,0(" #ptr ")\n"                                       \
 351         "ld     2,8(" #ptr ")\n"                                        \
 352         "mtctr  12\n"                                                   \
 353         "ld     11,16(" #ptr ")"
 354
 355 #ifdef USE_PPC64_OVERLAPPING_OPD
 356 # define OPD_ENT(name)  ".quad " BODY_PREFIX #name ", .TOC.@tocbase"
 357 #else
 358 # define OPD_ENT(name)  ".quad " BODY_PREFIX #name ", .TOC.@tocbase, 0"
 359 #endif
 360
 361 #define ENTRY_1(name)   \
 362         ".type   " BODY_PREFIX #name ",@function\n"                     \
 363         ".globl " #name "\n"                                            \
 364         ".pushsection \".opd\",\"aw\"\n"                                \
 365         ".p2align 3\n"                                                  \
 366 #name ":\n"                                                             \
 367         OPD_ENT (name) "\n"                                             \
 368         ".popsection"
 369
 370 #define DOT_PREFIX ""
 371 #define BODY_PREFIX ".LY"
 372 #define ENTRY_2(name)   \
 373         ".type " #name ",@function\n"                                   \
 374         ENTRY_1(name)
 375 #define END_2(name)     \
 376         ".size " #name ",.-" BODY_PREFIX #name "\n"                     \
 377         ".size " BODY_PREFIX #name ",.-" BODY_PREFIX #name
 378 #define LOCALENTRY(name)
 379
 380 #else /* _CALL_ELF */
 381
 382 #define PPC64_LOAD_FUNCPTR(ptr) \
 383         "mr     12," #ptr "\n"                                          \
 384         "mtctr  12"
 385
 386 #define DOT_PREFIX ""
 387 #define BODY_PREFIX ""
 388 #define ENTRY_2(name)   \
 389         ".type " #name ",@function\n"                                   \
 390         ".globl " #name
 391 #define END_2(name)     \
 392         ".size " #name ",.-" #name
 393 #define LOCALENTRY(name)        \
 394         "1: addis 2,12,.TOC.-1b@ha\n"                                   \
 395         "addi   2,2,.TOC.-1b@l\n"                                       \
 396         ".localentry " #name ",.-" #name
 397
 398 #endif /* _CALL_ELF */
 399
 400 #endif  /* __ASSEMBLER__ */