ghc/rts/StgCRun.c

   1 /* -----------------------------------------------------------------------------
   2  *
   3  * (c) The GHC Team, 1998-2003
   4  *
   5  * STG-to-C glue.
   6  *
   7  * To run an STG function from C land, call
   8  *
   9  *              rv = StgRun(f,BaseReg);
  10  *
  11  * where "f" is the STG function to call, and BaseReg is the address of the
  12  * RegTable for this run (we might have separate RegTables if we're running
  13  * multiple threads on an SMP machine).
  14  *
  15  * In the end, "f" must JMP to StgReturn (defined below),
  16  * passing the return-value "rv" in R1,
  17  * to return to the caller of StgRun returning "rv" in
  18  * the whatever way C returns a value.
  19  *
  20  * NOTE: StgRun/StgReturn do *NOT* load or store Hp or any
  21  * other registers (other than saving the C callee-saves
  22  * registers).  Instead, the called function "f" must do that
  23  * in STG land.
  24  *
  25  * GCC will have assumed that pushing/popping of C-stack frames is
  26  * going on when it generated its code, and used stack space
  27  * accordingly.  However, we actually {\em post-process away} all
  28  * such stack-framery (see \tr{ghc/driver/ghc-asm.lprl}). Things will
  29  * be OK however, if we initially make sure there are
  30  * @RESERVED_C_STACK_BYTES@ on the C-stack to begin with, for local
  31  * variables.
  32  *
  33  * -------------------------------------------------------------------------- */
  34
  35 #include "PosixSource.h"
  36
  37
  38 /*
  39  * We define the following (unused) global register variables, because for
  40  * some reason gcc generates sub-optimal code for StgRun() on the Alpha
  41  * (unnecessarily saving extra registers on the stack) if we don't.
  42  *
  43  * Why do it at the top of this file, rather than near StgRun() below?  Because
  44  * gcc doesn't let us define global register variables after any function
  45  * definition has been read.  Any point after #include "Stg.h" would be too
  46  * late.
  47  *
  48  * We define alpha_EXTRA_CAREFUL here to save $s6, $f8 and $f9 -- registers
  49  * that we don't use but which are callee-save registers.  The __divq() routine
  50  * in libc.a clobbers $s6.
  51  */
  52 #include "ghcconfig.h"
  53 #ifdef alpha_HOST_ARCH
  54 #define alpha_EXTRA_CAREFUL
  55 register long   fake_ra __asm__("$26");
  56 register long   fake_gp __asm__("$29");
  57 #ifdef alpha_EXTRA_CAREFUL
  58 register long   fake_s6 __asm__("$15");
  59 register double fake_f8 __asm__("$f8");
  60 register double fake_f9 __asm__("$f9");
  61 #endif
  62 #endif
  63
  64 /* include Stg.h first because we want real machine regs in here: we
  65  * have to get the value of R1 back from Stg land to C land intact.
  66  */
  67 #include "Stg.h"
  68 #include "Rts.h"
  69 #include "StgRun.h"
  70 #include "RtsFlags.h"
  71 #include "OSThreads.h"
  72 #include "Capability.h"
  73
  74 #ifdef DEBUG
  75 #include "RtsUtils.h"
  76 #include "Printer.h"
  77 #endif
  78
  79 #ifdef USE_MINIINTERPRETER
  80
  81 /* -----------------------------------------------------------------------------
  82    any architecture (using miniinterpreter)
  83    -------------------------------------------------------------------------- */
  84
  85 StgRegTable * StgRun(StgFunPtr f, StgRegTable *basereg STG_UNUSED)
  86 {
  87     while (f) {
  88         IF_DEBUG(interpreter,
  89             debugBelch("Jumping to ");
  90             printPtr((P_)f); fflush(stdout);
  91             debugBelch("\n");
  92             );
  93         f = (StgFunPtr) (f)();
  94     }
  95     return (StgRegTable *)R1.p;
  96 }
  97
  98 StgFunPtr StgReturn(void)
  99 {
 100     return 0;
 101 }
 102
 103 #else /* !USE_MINIINTERPRETER */
 104
 105 #ifdef LEADING_UNDERSCORE
 106 #define STG_RETURN "_StgReturn"
 107 #else
 108 #define STG_RETURN "StgReturn"
 109 #endif
 110
 111 /* -----------------------------------------------------------------------------
 112    x86 architecture
 113    -------------------------------------------------------------------------- */
 114
 115 #ifdef i386_HOST_ARCH
 116
 117 #ifdef darwin_TARGET_OS
 118 #define STG_GLOBAL ".globl "
 119 #else
 120 #define STG_GLOBAL ".global "
 121 #endif
 122
 123 StgRegTable *
 124 StgRun(StgFunPtr f, StgRegTable *basereg) {
 125
 126     unsigned char space[ RESERVED_C_STACK_BYTES + 4*sizeof(void *) ];
 127     StgRegTable * r;
 128
 129     __asm__ volatile (
 130         /*
 131          * save callee-saves registers on behalf of the STG code.
 132          */
 133         "movl %%esp, %%eax\n\t"
 134         "addl %4, %%eax\n\t"
 135         "movl %%ebx,0(%%eax)\n\t"
 136         "movl %%esi,4(%%eax)\n\t"
 137         "movl %%edi,8(%%eax)\n\t"
 138         "movl %%ebp,12(%%eax)\n\t"
 139         /*
 140          * Set BaseReg
 141          */
 142         "movl %3,%%ebx\n\t"
 143         /*
 144          * grab the function argument from the stack
 145          */
 146         "movl %2,%%eax\n\t"
 147
 148         /*
 149          * Darwin note:
 150          * The stack pointer has to be aligned to a multiple of 16 bytes at
 151          * this point. This works out correctly with gcc 4.0.1, but it might
 152          * break at any time in the future. TODO: Make this future-proof.
 153          */
 154
 155         /*
 156          * jump to it
 157          */
 158         "jmp *%%eax\n\t"
 159
 160         STG_GLOBAL STG_RETURN "\n"
 161         STG_RETURN ":\n\t"
 162
 163         "movl %%esi, %%eax\n\t"   /* Return value in R1  */
 164
 165         /*
 166          * restore callee-saves registers.  (Don't stomp on %%eax!)
 167          */
 168         "movl %%esp, %%edx\n\t"
 169         "addl %4, %%edx\n\t"
 170         "movl 0(%%edx),%%ebx\n\t"       /* restore the registers saved above */
 171         "movl 4(%%edx),%%esi\n\t"
 172         "movl 8(%%edx),%%edi\n\t"
 173         "movl 12(%%edx),%%ebp\n\t"
 174
 175       : "=&a" (r), "=m" (space)
 176       : "m" (f), "m" (basereg), "i" (RESERVED_C_STACK_BYTES)
 177       : "edx" /* stomps on %edx */
 178     );
 179
 180     return r;
 181 }
 182
 183 #endif
 184
 185 /* ----------------------------------------------------------------------------
 186    x86-64 is almost the same as plain x86.
 187
 188    I've done it using entirely inline assembler, because I couldn't
 189    get gcc to generate the correct subtraction from %rsp by using
 190    the local array variable trick.  It didn't seem to reserve
 191    enough space.  Oh well, it's not much harder this way.
 192
 193    ------------------------------------------------------------------------- */
 194
 195 #ifdef x86_64_HOST_ARCH
 196
 197 extern StgRegTable * StgRun(StgFunPtr f, StgRegTable *basereg);
 198
 199 static void GNUC3_ATTRIBUTE(used)
 200 StgRunIsImplementedInAssembler(void)
 201 {
 202     __asm__ volatile (
 203         /*
 204          * save callee-saves registers on behalf of the STG code.
 205          */
 206         ".globl StgRun\n"
 207         "StgRun:\n\t"
 208         "subq %0, %%rsp\n\t"
 209         "movq %%rsp, %%rax\n\t"
 210         "addq %0-48, %%rax\n\t"
 211         "movq %%rbx,0(%%rax)\n\t"
 212         "movq %%rbp,8(%%rax)\n\t"
 213         "movq %%r12,16(%%rax)\n\t"
 214         "movq %%r13,24(%%rax)\n\t"
 215         "movq %%r14,32(%%rax)\n\t"
 216         "movq %%r15,40(%%rax)\n\t"
 217         /*
 218          * Set BaseReg
 219          */
 220         "movq %%rsi,%%r13\n\t"
 221         /*
 222          * grab the function argument from the stack, and jump to it.
 223          */
 224         "movq %%rdi,%%rax\n\t"
 225         "jmp *%%rax\n\t"
 226
 227         ".global " STG_RETURN "\n"
 228         STG_RETURN ":\n\t"
 229
 230         "movq %%rbx, %%rax\n\t"   /* Return value in R1  */
 231
 232         /*
 233          * restore callee-saves registers.  (Don't stomp on %%rax!)
 234          */
 235         "movq %%rsp, %%rdx\n\t"
 236         "addq %0-48, %%rdx\n\t"
 237         "movq 0(%%rdx),%%rbx\n\t"       /* restore the registers saved above */
 238         "movq 8(%%rdx),%%rbp\n\t"
 239         "movq 16(%%rdx),%%r12\n\t"
 240         "movq 24(%%rdx),%%r13\n\t"
 241         "movq 32(%%rdx),%%r14\n\t"
 242         "movq 40(%%rdx),%%r15\n\t"
 243         "addq %0, %%rsp\n\t"
 244         "retq"
 245
 246         : : "i"(RESERVED_C_STACK_BYTES+48+8 /*stack frame size*/));
 247     /*
 248        HACK alert!
 249
 250        The x86_64 ABI specifies that on a procedure call, %rsp is
 251        aligned on a 16-byte boundary + 8.  That is, the first
 252        argument on the stack after the return address will be
 253        16-byte aligned.
 254
 255        Which should be fine: RESERVED_C_STACK_BYTES+48 is a multiple
 256        of 16 bytes.
 257
 258        BUT... when we do a C-call from STG land, gcc likes to put the
 259        stack alignment adjustment in the prolog.  eg. if we're calling
 260        a function with arguments in regs, gcc will insert 'subq $8,%rsp'
 261        in the prolog, to keep %rsp aligned (the return address is 8
 262        bytes, remember).  The mangler throws away the prolog, so we
 263        lose the stack alignment.
 264
 265        The hack is to add this extra 8 bytes to our %rsp adjustment
 266        here, so that throughout STG code, %rsp is 16-byte aligned,
 267        ready for a C-call.
 268
 269        A quick way to see if this is wrong is to compile this code:
 270
 271           main = System.Exit.exitWith ExitSuccess
 272
 273        And run it with +RTS -sstderr.  The stats code in the RTS, in
 274        particular statsPrintf(), relies on the stack alignment because
 275        it saves the %xmm regs on the stack, so it'll fall over if the
 276        stack isn't aligned, and calling exitWith from Haskell invokes
 277        shutdownHaskellAndExit using a C call.
 278
 279        Future gcc releases will almost certainly break this hack...
 280     */
 281 }
 282
 283 #endif /* x86-64 */
 284
 285 /* -----------------------------------------------------------------------------
 286    Sparc architecture
 287
 288    --
 289    OLD COMMENT from GHC-3.02:
 290
 291    We want tailjumps to be calls, because `call xxx' is the only Sparc
 292    branch that allows an arbitrary label as a target.  (Gcc's ``goto
 293    *target'' construct ends up loading the label into a register and
 294    then jumping, at the cost of two extra instructions for the 32-bit
 295    load.)
 296
 297    When entering the threaded world, we stash our return address in a
 298    known location so that \tr{%i7} is available as an extra
 299    callee-saves register.  Of course, we have to restore this when
 300    coming out of the threaded world.
 301
 302    I hate this god-forsaken architecture.  Since the top of the
 303    reserved stack space is used for globals and the bottom is reserved
 304    for outgoing arguments, we have to stick our return address
 305    somewhere in the middle.  Currently, I'm allowing 100 extra
 306    outgoing arguments beyond the first 6.  --JSM
 307
 308    Updated info (GHC 4.06): we don't appear to use %i7 any more, so
 309    I'm not sure whether we still need to save it.  Incedentally, what
 310    does the last paragraph above mean when it says "the top of the
 311    stack is used for globals"?  What globals?  --SDM
 312
 313    Updated info (GHC 4.08.2): not saving %i7 any more (see below).
 314    -------------------------------------------------------------------------- */
 315
 316 #ifdef sparc_HOST_ARCH
 317
 318 StgRegTable *
 319 StgRun(StgFunPtr f, StgRegTable *basereg) {
 320
 321     unsigned char space[RESERVED_C_STACK_BYTES];
 322 #if 0
 323     register void *i7 __asm__("%i7");
 324     ((void **)(space))[100] = i7;
 325 #endif
 326     f();
 327     __asm__ volatile (
 328             ".align 4\n"
 329             ".global " STG_RETURN "\n"
 330             STG_RETURN ":"
 331             : : : "l0","l1","l2","l3","l4","l5","l6","l7");
 332     /* we tell the C compiler that l0-l7 are clobbered on return to
 333      * StgReturn, otherwise it tries to use these to save eg. the
 334      * address of space[100] across the call.  The correct thing
 335      * to do would be to save all the callee-saves regs, but we
 336      * can't be bothered to do that.
 337      *
 338      * The code that gcc generates for this little fragment is now
 339      * terrible.  We could do much better by coding it directly in
 340      * assembler.
 341      */
 342 #if 0
 343     /* updated 4.08.2: we don't save %i7 in the middle of the reserved
 344      * space any more, since gcc tries to save its address across the
 345      * call to f(), this gets clobbered in STG land and we end up
 346      * dereferencing a bogus pointer in StgReturn.
 347      */
 348     __asm__ volatile ("ld %1,%0"
 349                       : "=r" (i7) : "m" (((void **)(space))[100]));
 350 #endif
 351     return (StgRegTable *)R1.i;
 352 }
 353
 354 #endif
 355
 356 /* -----------------------------------------------------------------------------
 357    alpha architecture
 358
 359    "The stack pointer (SP) must at all times denote an address that has octaword
 360     alignment. (This restriction has the side effect that the in-memory portion
 361     of the argument list, if any, will start on an octaword boundary.) Note that
 362     the stack grows toward lower addresses. During a procedure invocation, SP
 363     can never be set to a value that is higher than the value of SP at entry to
 364     that procedure invocation.
 365
 366    "The contents of the stack, located above the portion of the argument list
 367     (if any) that is passed in memory, belong to the calling procedure. Because
 368     they are part of the calling procedure, they should not be read or written
 369     by the called procedure, except as specified by indirect arguments or
 370     language-controlled up-level references.
 371
 372    "The SP value might be used by the hardware when raising exceptions and
 373     asynchronous interrupts. It must be assumed that the contents of the stack
 374     below the current SP value and within the stack for the current thread are
 375     continually and unpredictably modified, as specified in the _Alpha
 376     Architecture Reference Manual_, and as a result of asynchronous software
 377     actions."
 378
 379    -- Compaq Computer Corporation, Houston. Tru64 UNIX Calling Standard for
 380       Alpha Systems, 5.1 edition, August 2000, section 3.2.1.  http://www.
 381       tru64unix.compaq.com/docs/base_doc/DOCUMENTATION/V51_PDF/ARH9MBTE.PDF
 382    -------------------------------------------------------------------------- */
 383
 384 #ifdef alpha_HOST_ARCH
 385
 386 StgRegTable *
 387 StgRun(StgFunPtr f, StgRegTable *basereg)
 388 {
 389     register long   real_ra __asm__("$26"); volatile long   save_ra;
 390     register long   real_gp __asm__("$29"); volatile long   save_gp;
 391
 392     register long   real_s0 __asm__("$9" ); volatile long   save_s0;
 393     register long   real_s1 __asm__("$10"); volatile long   save_s1;
 394     register long   real_s2 __asm__("$11"); volatile long   save_s2;
 395     register long   real_s3 __asm__("$12"); volatile long   save_s3;
 396     register long   real_s4 __asm__("$13"); volatile long   save_s4;
 397     register long   real_s5 __asm__("$14"); volatile long   save_s5;
 398 #ifdef alpha_EXTRA_CAREFUL
 399     register long   real_s6 __asm__("$15"); volatile long   save_s6;
 400 #endif
 401
 402     register double real_f2 __asm__("$f2"); volatile double save_f2;
 403     register double real_f3 __asm__("$f3"); volatile double save_f3;
 404     register double real_f4 __asm__("$f4"); volatile double save_f4;
 405     register double real_f5 __asm__("$f5"); volatile double save_f5;
 406     register double real_f6 __asm__("$f6"); volatile double save_f6;
 407     register double real_f7 __asm__("$f7"); volatile double save_f7;
 408 #ifdef alpha_EXTRA_CAREFUL
 409     register double real_f8 __asm__("$f8"); volatile double save_f8;
 410     register double real_f9 __asm__("$f9"); volatile double save_f9;
 411 #endif
 412
 413     register StgFunPtr real_pv __asm__("$27");
 414
 415     StgRegTable * ret;
 416
 417     save_ra = real_ra;
 418     save_gp = real_gp;
 419
 420     save_s0 = real_s0;
 421     save_s1 = real_s1;
 422     save_s2 = real_s2;
 423     save_s3 = real_s3;
 424     save_s4 = real_s4;
 425     save_s5 = real_s5;
 426 #ifdef alpha_EXTRA_CAREFUL
 427     save_s6 = real_s6;
 428 #endif
 429
 430     save_f2 = real_f2;
 431     save_f3 = real_f3;
 432     save_f4 = real_f4;
 433     save_f5 = real_f5;
 434     save_f6 = real_f6;
 435     save_f7 = real_f7;
 436 #ifdef alpha_EXTRA_CAREFUL
 437     save_f8 = real_f8;
 438     save_f9 = real_f9;
 439 #endif
 440
 441     real_pv = f;
 442
 443     __asm__ volatile(   "lda $30,-%0($30)"      "\n"
 444                 "\t"    "jmp ($27)"             "\n"
 445                 "\t"    ".align 3"              "\n"
 446                 ".globl " STG_RETURN            "\n"
 447                 STG_RETURN ":"                  "\n"
 448                 "\t"    "lda $30,%0($30)"       "\n"
 449                 : : "K" (RESERVED_C_STACK_BYTES));
 450
 451     ret = real_s5;
 452
 453     real_s0 = save_s0;
 454     real_s1 = save_s1;
 455     real_s2 = save_s2;
 456     real_s3 = save_s3;
 457     real_s4 = save_s4;
 458     real_s5 = save_s5;
 459 #ifdef alpha_EXTRA_CAREFUL
 460     real_s6 = save_s6;
 461 #endif
 462
 463     real_f2 = save_f2;
 464     real_f3 = save_f3;
 465     real_f4 = save_f4;
 466     real_f5 = save_f5;
 467     real_f6 = save_f6;
 468     real_f7 = save_f7;
 469 #ifdef alpha_EXTRA_CAREFUL
 470     real_f8 = save_f8;
 471     real_f9 = save_f9;
 472 #endif
 473
 474     real_ra = save_ra;
 475     real_gp = save_gp;
 476
 477     return ret;
 478 }
 479
 480 #endif /* alpha_HOST_ARCH */
 481
 482 /* -----------------------------------------------------------------------------
 483    HP-PA architecture
 484    -------------------------------------------------------------------------- */
 485
 486 #ifdef hppa1_1_HOST_ARCH
 487
 488 StgRegTable *
 489 StgRun(StgFunPtr f, StgRegTable *basereg)
 490 {
 491     StgChar space[RESERVED_C_STACK_BYTES+16*sizeof(long)+10*sizeof(double)];
 492     StgRegTable * ret;
 493
 494     __asm__ volatile ("ldo %0(%%r30),%%r19\n"
 495                       "\tstw %%r3, 0(0,%%r19)\n"
 496                       "\tstw %%r4, 4(0,%%r19)\n"
 497                       "\tstw %%r5, 8(0,%%r19)\n"
 498                       "\tstw %%r6,12(0,%%r19)\n"
 499                       "\tstw %%r7,16(0,%%r19)\n"
 500                       "\tstw %%r8,20(0,%%r19)\n"
 501                       "\tstw %%r9,24(0,%%r19)\n"
 502                       "\tstw %%r10,28(0,%%r19)\n"
 503                       "\tstw %%r11,32(0,%%r19)\n"
 504                       "\tstw %%r12,36(0,%%r19)\n"
 505                       "\tstw %%r13,40(0,%%r19)\n"
 506                       "\tstw %%r14,44(0,%%r19)\n"
 507                       "\tstw %%r15,48(0,%%r19)\n"
 508                       "\tstw %%r16,52(0,%%r19)\n"
 509                       "\tstw %%r17,56(0,%%r19)\n"
 510                       "\tstw %%r18,60(0,%%r19)\n"
 511                       "\tldo 80(%%r19),%%r19\n"
 512                       "\tfstds %%fr12,-16(0,%%r19)\n"
 513                       "\tfstds %%fr13, -8(0,%%r19)\n"
 514                       "\tfstds %%fr14,  0(0,%%r19)\n"
 515                       "\tfstds %%fr15,  8(0,%%r19)\n"
 516                       "\tldo 32(%%r19),%%r19\n"
 517                       "\tfstds %%fr16,-16(0,%%r19)\n"
 518                       "\tfstds %%fr17, -8(0,%%r19)\n"
 519                       "\tfstds %%fr18,  0(0,%%r19)\n"
 520                       "\tfstds %%fr19,  8(0,%%r19)\n"
 521                       "\tldo 32(%%r19),%%r19\n"
 522                       "\tfstds %%fr20,-16(0,%%r19)\n"
 523                       "\tfstds %%fr21, -8(0,%%r19)\n" : :
 524                       "n" (-(116 * sizeof(long) + 10 * sizeof(double))) : "%r19"
 525                       );
 526
 527     f();
 528
 529     __asm__ volatile (".align 4\n"
 530                       "\t.EXPORT " STG_RETURN ",CODE\n"
 531                       "\t.EXPORT " STG_RETURN ",ENTRY,PRIV_LEV=3\n"
 532                       STG_RETURN "\n"
 533                       /* "\tldo %0(%%r3),%%r19\n" */
 534                       "\tldo %1(%%r30),%%r19\n"
 535                       "\tcopy %%r11, %0\n"  /* save R1 */
 536                       "\tldw  0(0,%%r19),%%r3\n"
 537                       "\tldw  4(0,%%r19),%%r4\n"
 538                       "\tldw  8(0,%%r19),%%r5\n"
 539                       "\tldw 12(0,%%r19),%%r6\n"
 540                       "\tldw 16(0,%%r19),%%r7\n"
 541                       "\tldw 20(0,%%r19),%%r8\n"
 542                       "\tldw 24(0,%%r19),%%r9\n"
 543                       "\tldw 28(0,%%r19),%%r10\n"
 544                       "\tldw 32(0,%%r19),%%r11\n"
 545                       "\tldw 36(0,%%r19),%%r12\n"
 546                       "\tldw 40(0,%%r19),%%r13\n"
 547                       "\tldw 44(0,%%r19),%%r14\n"
 548                       "\tldw 48(0,%%r19),%%r15\n"
 549                       "\tldw 52(0,%%r19),%%r16\n"
 550                       "\tldw 56(0,%%r19),%%r17\n"
 551                       "\tldw 60(0,%%r19),%%r18\n"
 552                       "\tldo 80(%%r19),%%r19\n"
 553                       "\tfldds -16(0,%%r19),%%fr12\n"
 554                       "\tfldds  -8(0,%%r19),%%fr13\n"
 555                       "\tfldds   0(0,%%r19),%%fr14\n"
 556                       "\tfldds   8(0,%%r19),%%fr15\n"
 557                       "\tldo 32(%%r19),%%r19\n"
 558                       "\tfldds -16(0,%%r19),%%fr16\n"
 559                       "\tfldds  -8(0,%%r19),%%fr17\n"
 560                       "\tfldds   0(0,%%r19),%%fr18\n"
 561                       "\tfldds   8(0,%%r19),%%fr19\n"
 562                       "\tldo 32(%%r19),%%r19\n"
 563                       "\tfldds -16(0,%%r19),%%fr20\n"
 564                       "\tfldds  -8(0,%%r19),%%fr21\n"
 565                          : "=r" (ret)
 566                          : "n" (-(116 * sizeof(long) + 10 * sizeof(double)))
 567                          : "%r19"
 568                       );
 569
 570     return ret;
 571 }
 572
 573 #endif /* hppa1_1_HOST_ARCH */
 574
 575 /* -----------------------------------------------------------------------------
 576    PowerPC architecture
 577
 578    Everything is in assembler, so we don't have to deal with GCC...
 579
 580    -------------------------------------------------------------------------- */
 581
 582 #ifdef powerpc_HOST_ARCH
 583
 584 extern StgRegTable * StgRun(StgFunPtr f, StgRegTable *basereg);
 585
 586 #ifdef darwin_HOST_OS
 587 void StgRunIsImplementedInAssembler(void)
 588 {
 589 #if HAVE_SUBSECTIONS_VIA_SYMBOLS
 590             // if the toolchain supports deadstripping, we have to
 591             // prevent it here (it tends to get confused here).
 592         __asm__ volatile (".no_dead_strip _StgRunIsImplementedInAssembler");
 593 #endif
 594         __asm__ volatile (
 595                 "\n.globl _StgRun\n"
 596                 "_StgRun:\n"
 597                 "\tmflr r0\n"
 598                 "\tbl saveFP # f14\n"
 599                 "\tstmw r13,-220(r1)\n"
 600                 "\tstwu r1,-%0(r1)\n"
 601                 "\tmr r27,r4\n" // BaseReg == r27
 602                 "\tmtctr r3\n"
 603                 "\tmr r12,r3\n"
 604                 "\tbctr\n"
 605                 ".globl _StgReturn\n"
 606                 "_StgReturn:\n"
 607                 "\tmr r3,r14\n"
 608                 "\tla r1,%0(r1)\n"
 609                 "\tlmw r13,-220(r1)\n"
 610                 "\tb restFP # f14\n"
 611         : : "i"(RESERVED_C_STACK_BYTES+224 /*stack frame size*/));
 612 }
 613 #else
 614
 615 // This version is for PowerPC Linux.
 616
 617 // Differences from the Darwin/Mac OS X version:
 618 // *) Different Assembler Syntax
 619 // *) Doesn't use Register Saving Helper Functions (although they exist somewhere)
 620 // *) We may not access positive stack offsets
 621 //    (no "Red Zone" as in the Darwin ABI)
 622 // *) The Link Register is saved to a different offset in the caller's stack frame
 623 //    (Linux: 4(r1), Darwin 8(r1))
 624
 625 static void GNUC3_ATTRIBUTE(used)
 626 StgRunIsImplementedInAssembler(void)
 627 {
 628         __asm__ volatile (
 629                 "\t.globl StgRun\n"
 630                 "\t.type StgRun,@function\n"
 631                 "StgRun:\n"
 632                 "\tmflr 0\n"
 633                 "\tstw 0,4(1)\n"
 634                 "\tmr 5,1\n"
 635                 "\tstwu 1,-%0(1)\n"
 636                 "\tstmw 13,-220(5)\n"
 637                 "\tstfd 14,-144(5)\n"
 638                 "\tstfd 15,-136(5)\n"
 639                 "\tstfd 16,-128(5)\n"
 640                 "\tstfd 17,-120(5)\n"
 641                 "\tstfd 18,-112(5)\n"
 642                 "\tstfd 19,-104(5)\n"
 643                 "\tstfd 20,-96(5)\n"
 644                 "\tstfd 21,-88(5)\n"
 645                 "\tstfd 22,-80(5)\n"
 646                 "\tstfd 23,-72(5)\n"
 647                 "\tstfd 24,-64(5)\n"
 648                 "\tstfd 25,-56(5)\n"
 649                 "\tstfd 26,-48(5)\n"
 650                 "\tstfd 27,-40(5)\n"
 651                 "\tstfd 28,-32(5)\n"
 652                 "\tstfd 29,-24(5)\n"
 653                 "\tstfd 30,-16(5)\n"
 654                 "\tstfd 31,-8(5)\n"
 655                 "\tmr 27,4\n"  // BaseReg == r27
 656                 "\tmtctr 3\n"
 657                 "\tmr 12,3\n"
 658                 "\tbctr\n"
 659                 ".globl StgReturn\n"
 660                 "\t.type StgReturn,@function\n"
 661                 "StgReturn:\n"
 662                 "\tmr 3,14\n"
 663                 "\tla 5,%0(1)\n"
 664                 "\tlmw 13,-220(5)\n"
 665                 "\tlfd 14,-144(5)\n"
 666                 "\tlfd 15,-136(5)\n"
 667                 "\tlfd 16,-128(5)\n"
 668                 "\tlfd 17,-120(5)\n"
 669                 "\tlfd 18,-112(5)\n"
 670                 "\tlfd 19,-104(5)\n"
 671                 "\tlfd 20,-96(5)\n"
 672                 "\tlfd 21,-88(5)\n"
 673                 "\tlfd 22,-80(5)\n"
 674                 "\tlfd 23,-72(5)\n"
 675                 "\tlfd 24,-64(5)\n"
 676                 "\tlfd 25,-56(5)\n"
 677                 "\tlfd 26,-48(5)\n"
 678                 "\tlfd 27,-40(5)\n"
 679                 "\tlfd 28,-32(5)\n"
 680                 "\tlfd 29,-24(5)\n"
 681                 "\tlfd 30,-16(5)\n"
 682                 "\tlfd 31,-8(5)\n"
 683                 "\tmr 1,5\n"
 684                 "\tlwz 0,4(1)\n"
 685                 "\tmtlr 0\n"
 686                 "\tblr\n"
 687         : : "i"(RESERVED_C_STACK_BYTES+224 /*stack frame size*/));
 688 }
 689 #endif
 690
 691 #endif
 692
 693 /* -----------------------------------------------------------------------------
 694    PowerPC 64 architecture
 695
 696    Everything is in assembler, so we don't have to deal with GCC...
 697
 698    -------------------------------------------------------------------------- */
 699
 700 #ifdef powerpc64_HOST_ARCH
 701
 702 #ifdef linux_HOST_OS
 703 extern StgRegTable * StgRun(StgFunPtr f, StgRegTable *basereg);
 704
 705 static void GNUC3_ATTRIBUTE(used)
 706 StgRunIsImplementedInAssembler(void)
 707 {
 708         // r0 volatile
 709         // r1 stack pointer
 710         // r2 toc - needs to be saved
 711         // r3-r10 argument passing, volatile
 712         // r11, r12 very volatile (not saved across cross-module calls)
 713         // r13 thread local state (never modified, don't need to save)
 714         // r14-r31 callee-save
 715         __asm__ volatile (
 716                 ".section \".opd\",\"aw\"\n"
 717                 ".align 3\n"
 718                 ".globl StgRun\n"
 719                 "StgRun:\n"
 720                         "\t.quad\t.StgRun,.TOC.@tocbase,0\n"
 721                         "\t.size StgRun,24\n"
 722                 ".globl StgReturn\n"
 723                 "StgReturn:\n"
 724                         "\t.quad\t.StgReturn,.TOC.@tocbase,0\n"
 725                         "\t.size StgReturn,24\n"
 726                 ".previous\n"
 727                 ".globl .StgRun\n"
 728                 ".type .StgRun,@function\n"
 729                 ".StgRun:\n"
 730                         "\tmflr 0\n"
 731                         "\tmr 5, 1\n"
 732                         "\tstd 0, 16(1)\n"
 733                         "\tstdu 1, -%0(1)\n"
 734                         "\tstd 2, -296(5)\n"
 735                         "\tstd 14, -288(5)\n"
 736                         "\tstd 15, -280(5)\n"
 737                         "\tstd 16, -272(5)\n"
 738                         "\tstd 17, -264(5)\n"
 739                         "\tstd 18, -256(5)\n"
 740                         "\tstd 19, -248(5)\n"
 741                         "\tstd 20, -240(5)\n"
 742                         "\tstd 21, -232(5)\n"
 743                         "\tstd 22, -224(5)\n"
 744                         "\tstd 23, -216(5)\n"
 745                         "\tstd 24, -208(5)\n"
 746                         "\tstd 25, -200(5)\n"
 747                         "\tstd 26, -192(5)\n"
 748                         "\tstd 27, -184(5)\n"
 749                         "\tstd 28, -176(5)\n"
 750                         "\tstd 29, -168(5)\n"
 751                         "\tstd 30, -160(5)\n"
 752                         "\tstd 31, -152(5)\n"
 753                         "\tstfd 14, -144(5)\n"
 754                         "\tstfd 15, -136(5)\n"
 755                         "\tstfd 16, -128(5)\n"
 756                         "\tstfd 17, -120(5)\n"
 757                         "\tstfd 18, -112(5)\n"
 758                         "\tstfd 19, -104(5)\n"
 759                         "\tstfd 20, -96(5)\n"
 760                         "\tstfd 21, -88(5)\n"
 761                         "\tstfd 22, -80(5)\n"
 762                         "\tstfd 23, -72(5)\n"
 763                         "\tstfd 24, -64(5)\n"
 764                         "\tstfd 25, -56(5)\n"
 765                         "\tstfd 26, -48(5)\n"
 766                         "\tstfd 27, -40(5)\n"
 767                         "\tstfd 28, -32(5)\n"
 768                         "\tstfd 29, -24(5)\n"
 769                         "\tstfd 30, -16(5)\n"
 770                         "\tstfd 31, -8(5)\n"
 771                         "\tmr 27, 4\n"  // BaseReg == r27
 772                         "\tld 2, 8(3)\n"
 773                         "\tld 3, 0(3)\n"
 774                         "\tmtctr 3\n"
 775                         "\tbctr\n"
 776                 ".globl .StgReturn\n"
 777                 ".type .StgReturn,@function\n"
 778                 ".StgReturn:\n"
 779                         "\tmr 3,14\n"
 780                         "\tla 5, %0(1)\n" // load address == addi r5, r1, %0
 781                         "\tld 2, -296(5)\n"
 782                         "\tld 14, -288(5)\n"
 783                         "\tld 15, -280(5)\n"
 784                         "\tld 16, -272(5)\n"
 785                         "\tld 17, -264(5)\n"
 786                         "\tld 18, -256(5)\n"
 787                         "\tld 19, -248(5)\n"
 788                         "\tld 20, -240(5)\n"
 789                         "\tld 21, -232(5)\n"
 790                         "\tld 22, -224(5)\n"
 791                         "\tld 23, -216(5)\n"
 792                         "\tld 24, -208(5)\n"
 793                         "\tld 25, -200(5)\n"
 794                         "\tld 26, -192(5)\n"
 795                         "\tld 27, -184(5)\n"
 796                         "\tld 28, -176(5)\n"
 797                         "\tld 29, -168(5)\n"
 798                         "\tld 30, -160(5)\n"
 799                         "\tld 31, -152(5)\n"
 800                         "\tlfd 14, -144(5)\n"
 801                         "\tlfd 15, -136(5)\n"
 802                         "\tlfd 16, -128(5)\n"
 803                         "\tlfd 17, -120(5)\n"
 804                         "\tlfd 18, -112(5)\n"
 805                         "\tlfd 19, -104(5)\n"
 806                         "\tlfd 20, -96(5)\n"
 807                         "\tlfd 21, -88(5)\n"
 808                         "\tlfd 22, -80(5)\n"
 809                         "\tlfd 23, -72(5)\n"
 810                         "\tlfd 24, -64(5)\n"
 811                         "\tlfd 25, -56(5)\n"
 812                         "\tlfd 26, -48(5)\n"
 813                         "\tlfd 27, -40(5)\n"
 814                         "\tlfd 28, -32(5)\n"
 815                         "\tlfd 29, -24(5)\n"
 816                         "\tlfd 30, -16(5)\n"
 817                         "\tlfd 31, -8(5)\n"
 818                         "\tmr 1, 5\n"
 819                         "\tld 0, 16(1)\n"
 820                         "\tmtlr 0\n"
 821                         "\tblr\n"
 822         : : "i"(RESERVED_C_STACK_BYTES+304 /*stack frame size*/));
 823 }
 824 #else // linux_HOST_OS
 825 #error Only linux support for power64 right now.
 826 #endif
 827
 828 #endif
 829
 830 /* -----------------------------------------------------------------------------
 831    IA64 architecture
 832
 833    Again, in assembler - so we can fiddle with the register stack, and because
 834    gcc doesn't handle asm-clobbered callee-saves correctly.
 835
 836    loc0  - loc15: preserved locals
 837    loc16 - loc28: STG registers
 838            loc29: saved ar.pfs
 839            loc30: saved b0
 840            loc31: saved gp (gcc 3.3 uses this slot)
 841    -------------------------------------------------------------------------- */
 842
 843 #ifdef ia64_HOST_ARCH
 844
 845 /* the memory stack is rarely used, so 16K is excessive */
 846 #undef RESERVED_C_STACK_BYTES
 847 #define RESERVED_C_STACK_BYTES 1024
 848
 849 #if ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 3)
 850 /* gcc 3.3+: leave an extra slot for gp saves */
 851 #define LOCALS 32
 852 #else
 853 #define LOCALS 31
 854 #endif
 855
 856 static void GNUC3_ATTRIBUTE(used)
 857 StgRunIsImplementedInAssembler(void)
 858 {
 859     __asm__ volatile(
 860                 ".global StgRun\n"
 861                 "StgRun:\n"
 862                 "\talloc loc29 = ar.pfs, 0, %1, 8, 0\n" /* setup register frame */
 863                 "\tld8 r18 = [r32],8\n"                 /* get procedure address */
 864                 "\tadds sp = -%0, sp ;;\n"              /* setup stack */
 865                 "\tld8 gp = [r32]\n"                    /* get procedure GP */
 866                 "\tadds r16 = %0-(6*16), sp\n"
 867                 "\tadds r17 = %0-(5*16), sp ;;\n"
 868                 "\tstf.spill [r16] = f16,32\n"          /* spill callee-saved fp regs */
 869                 "\tstf.spill [r17] = f17,32\n"
 870                 "\tmov b6 = r18 ;;\n"                   /* set target address */
 871                 "\tstf.spill [r16] = f18,32\n"
 872                 "\tstf.spill [r17] = f19,32\n"
 873                 "\tmov loc30 = b0 ;;\n"                 /* save return address */
 874                 "\tstf.spill [r16] = f20,32\n"
 875                 "\tstf.spill [r17] = f21,32\n"
 876                 "\tbr.few b6 ;;\n"                      /* branch to function */
 877                 ".global StgReturn\n"
 878                 "StgReturn:\n"
 879                 "\tmov r8 = loc16\n"            /* return value in r8 */
 880                 "\tadds r16 = %0-(6*16), sp\n"
 881                 "\tadds r17 = %0-(5*16), sp ;;\n"
 882                 "\tldf.fill f16 = [r16],32\n"   /* start restoring fp regs */
 883                 "\tldf.fill f17 = [r17],32\n"
 884                 "\tmov ar.pfs = loc29 ;;\n"     /* restore register frame */
 885                 "\tldf.fill f18 = [r16],32\n"
 886                 "\tldf.fill f19 = [r17],32\n"
 887                 "\tmov b0 = loc30 ;;\n"         /* restore return address */
 888                 "\tldf.fill f20 = [r16],32\n"
 889                 "\tldf.fill f21 = [r17],32\n"
 890                 "\tadds sp = %0, sp\n"          /* restore stack */
 891                 "\tbr.ret.sptk.many b0 ;;\n"    /* return */
 892         : : "i"(RESERVED_C_STACK_BYTES + 6*16), "i"(LOCALS));
 893 }
 894
 895 #endif
 896
 897 #endif /* !USE_MINIINTERPRETER */