gcc/config/vax/vax.c

   1 /* Subroutines for insn-output.c for VAX.
   2    Copyright (C) 1987, 1994, 1995, 1997, 1998, 1999, 2000, 2001, 2002, 2004
   3    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
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public 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 COPYING.  If not, write to
  19 the Free Software Foundation, 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "tm.h"
  26 #include "rtl.h"
  27 #include "tree.h"
  28 #include "regs.h"
  29 #include "hard-reg-set.h"
  30 #include "real.h"
  31 #include "insn-config.h"
  32 #include "conditions.h"
  33 #include "function.h"
  34 #include "output.h"
  35 #include "insn-attr.h"
  36 #include "recog.h"
  37 #include "expr.h"
  38 #include "optabs.h"
  39 #include "flags.h"
  40 #include "debug.h"
  41 #include "toplev.h"
  42 #include "tm_p.h"
  43 #include "target.h"
  44 #include "target-def.h"
  45
  46 static void vax_output_function_prologue (FILE *, HOST_WIDE_INT);
  47 static void vax_file_start (void);
  48 static void vax_init_libfuncs (void);
  49 static void vax_output_mi_thunk (FILE *, tree, HOST_WIDE_INT,
  50                                  HOST_WIDE_INT, tree);
  51 static int vax_address_cost_1 (rtx);
  52 static int vax_address_cost (rtx);
  53 static int vax_rtx_costs_1 (rtx, enum rtx_code, enum rtx_code);
  54 static bool vax_rtx_costs (rtx, int, int, int *);
  55 static rtx vax_struct_value_rtx (tree, int);
  56 \f
  57 /* Initialize the GCC target structure.  */
  58 #undef TARGET_ASM_ALIGNED_HI_OP
  59 #define TARGET_ASM_ALIGNED_HI_OP "\t.word\t"
  60
  61 #undef TARGET_ASM_FUNCTION_PROLOGUE
  62 #define TARGET_ASM_FUNCTION_PROLOGUE vax_output_function_prologue
  63
  64 #undef TARGET_ASM_FILE_START
  65 #define TARGET_ASM_FILE_START vax_file_start
  66 #undef TARGET_ASM_FILE_START_APP_OFF
  67 #define TARGET_ASM_FILE_START_APP_OFF true
  68
  69 #undef TARGET_INIT_LIBFUNCS
  70 #define TARGET_INIT_LIBFUNCS vax_init_libfuncs
  71
  72 #undef TARGET_ASM_OUTPUT_MI_THUNK
  73 #define TARGET_ASM_OUTPUT_MI_THUNK vax_output_mi_thunk
  74 #undef TARGET_ASM_CAN_OUTPUT_MI_THUNK
  75 #define TARGET_ASM_CAN_OUTPUT_MI_THUNK default_can_output_mi_thunk_no_vcall
  76
  77 #undef TARGET_RTX_COSTS
  78 #define TARGET_RTX_COSTS vax_rtx_costs
  79 #undef TARGET_ADDRESS_COST
  80 #define TARGET_ADDRESS_COST vax_address_cost
  81
  82 #undef TARGET_PROMOTE_PROTOTYPES
  83 #define TARGET_PROMOTE_PROTOTYPES hook_bool_tree_true
  84
  85 #undef TARGET_STRUCT_VALUE_RTX
  86 #define TARGET_STRUCT_VALUE_RTX vax_struct_value_rtx
  87
  88 struct gcc_target targetm = TARGET_INITIALIZER;
  89 \f
  90 /* Set global variables as needed for the options enabled.  */
  91
  92 void
  93 override_options (void)
  94 {
  95   /* We're VAX floating point, not IEEE floating point.  */
  96   if (TARGET_G_FLOAT)
  97     REAL_MODE_FORMAT (DFmode) = &vax_g_format;
  98 }
  99
 100 /* Generate the assembly code for function entry.  FILE is a stdio
 101    stream to output the code to.  SIZE is an int: how many units of
 102    temporary storage to allocate.
 103
 104    Refer to the array `regs_ever_live' to determine which registers to
 105    save; `regs_ever_live[I]' is nonzero if register number I is ever
 106    used in the function.  This function is responsible for knowing
 107    which registers should not be saved even if used.  */
 108
 109 static void
 110 vax_output_function_prologue (FILE * file, HOST_WIDE_INT size)
 111 {
 112   register int regno;
 113   register int mask = 0;
 114
 115   for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
 116     if (regs_ever_live[regno] && !call_used_regs[regno])
 117       mask |= 1 << regno;
 118
 119   fprintf (file, "\t.word 0x%x\n", mask);
 120
 121   if (dwarf2out_do_frame ())
 122     {
 123       const char *label = dwarf2out_cfi_label ();
 124       int offset = 0;
 125
 126       for (regno = FIRST_PSEUDO_REGISTER-1; regno >= 0; --regno)
 127         if (regs_ever_live[regno] && !call_used_regs[regno])
 128           dwarf2out_reg_save (label, regno, offset -= 4);
 129
 130       dwarf2out_reg_save (label, PC_REGNUM, offset -= 4);
 131       dwarf2out_reg_save (label, FRAME_POINTER_REGNUM, offset -= 4);
 132       dwarf2out_reg_save (label, ARG_POINTER_REGNUM, offset -= 4);
 133       dwarf2out_def_cfa (label, FRAME_POINTER_REGNUM, -(offset - 4));
 134     }
 135
 136   size -= STARTING_FRAME_OFFSET;
 137   if (size >= 64)
 138     asm_fprintf (file, "\tmovab %wd(%Rsp),%Rsp\n", -size);
 139   else if (size)
 140     asm_fprintf (file, "\tsubl2 $%wd,%Rsp\n", size);
 141 }
 142
 143 /* When debugging with stabs, we want to output an extra dummy label
 144    so that gas can distinguish between D_float and G_float prior to
 145    processing the .stabs directive identifying type double.  */
 146 static void
 147 vax_file_start (void)
 148 {
 149   default_file_start ();
 150
 151   if (write_symbols == DBX_DEBUG)
 152     fprintf (asm_out_file, "___vax_%c_doubles:\n", ASM_DOUBLE_CHAR);
 153 }
 154
 155 /* We can use the BSD C library routines for the libgcc calls that are
 156    still generated, since that's what they boil down to anyways.  When
 157    ELF, avoid the user's namespace.  */
 158
 159 static void
 160 vax_init_libfuncs (void)
 161 {
 162   set_optab_libfunc (udiv_optab, SImode, TARGET_ELF ? "*__udiv" : "*udiv");
 163   set_optab_libfunc (umod_optab, SImode, TARGET_ELF ? "*__urem" : "*urem");
 164 }
 165
 166 /* This is like nonimmediate_operand with a restriction on the type of MEM.  */
 167
 168 void
 169 split_quadword_operands (rtx * operands, rtx * low, int n ATTRIBUTE_UNUSED)
 170 {
 171   int i;
 172   /* Split operands.  */
 173
 174   low[0] = low[1] = low[2] = 0;
 175   for (i = 0; i < 3; i++)
 176     {
 177       if (low[i])
 178         /* it's already been figured out */;
 179       else if (GET_CODE (operands[i]) == MEM
 180                && (GET_CODE (XEXP (operands[i], 0)) == POST_INC))
 181         {
 182           rtx addr = XEXP (operands[i], 0);
 183           operands[i] = low[i] = gen_rtx_MEM (SImode, addr);
 184           if (which_alternative == 0 && i == 0)
 185             {
 186               addr = XEXP (operands[i], 0);
 187               operands[i+1] = low[i+1] = gen_rtx_MEM (SImode, addr);
 188             }
 189         }
 190       else
 191         {
 192           low[i] = operand_subword (operands[i], 0, 0, DImode);
 193           operands[i] = operand_subword (operands[i], 1, 0, DImode);
 194         }
 195     }
 196 }
 197 \f
 198 void
 199 print_operand_address (FILE * file, register rtx addr)
 200 {
 201   register rtx reg1, breg, ireg;
 202   rtx offset;
 203
 204  retry:
 205   switch (GET_CODE (addr))
 206     {
 207     case MEM:
 208       fprintf (file, "*");
 209       addr = XEXP (addr, 0);
 210       goto retry;
 211
 212     case REG:
 213       fprintf (file, "(%s)", reg_names[REGNO (addr)]);
 214       break;
 215
 216     case PRE_DEC:
 217       fprintf (file, "-(%s)", reg_names[REGNO (XEXP (addr, 0))]);
 218       break;
 219
 220     case POST_INC:
 221       fprintf (file, "(%s)+", reg_names[REGNO (XEXP (addr, 0))]);
 222       break;
 223
 224     case PLUS:
 225       /* There can be either two or three things added here.  One must be a
 226          REG.  One can be either a REG or a MULT of a REG and an appropriate
 227          constant, and the third can only be a constant or a MEM.
 228
 229          We get these two or three things and put the constant or MEM in
 230          OFFSET, the MULT or REG in IREG, and the REG in BREG.  If we have
 231          a register and can't tell yet if it is a base or index register,
 232          put it into REG1.  */
 233
 234       reg1 = 0; ireg = 0; breg = 0; offset = 0;
 235
 236       if (CONSTANT_ADDRESS_P (XEXP (addr, 0))
 237           || GET_CODE (XEXP (addr, 0)) == MEM)
 238         {
 239           offset = XEXP (addr, 0);
 240           addr = XEXP (addr, 1);
 241         }
 242       else if (CONSTANT_ADDRESS_P (XEXP (addr, 1))
 243                || GET_CODE (XEXP (addr, 1)) == MEM)
 244         {
 245           offset = XEXP (addr, 1);
 246           addr = XEXP (addr, 0);
 247         }
 248       else if (GET_CODE (XEXP (addr, 1)) == MULT)
 249         {
 250           ireg = XEXP (addr, 1);
 251           addr = XEXP (addr, 0);
 252         }
 253       else if (GET_CODE (XEXP (addr, 0)) == MULT)
 254         {
 255           ireg = XEXP (addr, 0);
 256           addr = XEXP (addr, 1);
 257         }
 258       else if (GET_CODE (XEXP (addr, 1)) == REG)
 259         {
 260           reg1 = XEXP (addr, 1);
 261           addr = XEXP (addr, 0);
 262         }
 263       else if (GET_CODE (XEXP (addr, 0)) == REG)
 264         {
 265           reg1 = XEXP (addr, 0);
 266           addr = XEXP (addr, 1);
 267         }
 268       else
 269         abort ();
 270
 271       if (GET_CODE (addr) == REG)
 272         {
 273           if (reg1)
 274             ireg = addr;
 275           else
 276             reg1 = addr;
 277         }
 278       else if (GET_CODE (addr) == MULT)
 279         ireg = addr;
 280       else if (GET_CODE (addr) == PLUS)
 281         {
 282           if (CONSTANT_ADDRESS_P (XEXP (addr, 0))
 283               || GET_CODE (XEXP (addr, 0)) == MEM)
 284             {
 285               if (offset)
 286                 {
 287                   if (GET_CODE (offset) == CONST_INT)
 288                     offset = plus_constant (XEXP (addr, 0), INTVAL (offset));
 289                   else if (GET_CODE (XEXP (addr, 0)) == CONST_INT)
 290                     offset = plus_constant (offset, INTVAL (XEXP (addr, 0)));
 291                   else
 292                     abort ();
 293                 }
 294               offset = XEXP (addr, 0);
 295             }
 296           else if (GET_CODE (XEXP (addr, 0)) == REG)
 297             {
 298               if (reg1)
 299                 ireg = reg1, breg = XEXP (addr, 0), reg1 = 0;
 300               else
 301                 reg1 = XEXP (addr, 0);
 302             }
 303           else if (GET_CODE (XEXP (addr, 0)) == MULT)
 304             {
 305               if (ireg)
 306                 abort ();
 307               ireg = XEXP (addr, 0);
 308             }
 309           else
 310             abort ();
 311
 312           if (CONSTANT_ADDRESS_P (XEXP (addr, 1))
 313               || GET_CODE (XEXP (addr, 1)) == MEM)
 314             {
 315               if (offset)
 316                 {
 317                   if (GET_CODE (offset) == CONST_INT)
 318                     offset = plus_constant (XEXP (addr, 1), INTVAL (offset));
 319                   else if (GET_CODE (XEXP (addr, 1)) == CONST_INT)
 320                     offset = plus_constant (offset, INTVAL (XEXP (addr, 1)));
 321                   else
 322                     abort ();
 323                 }
 324               offset = XEXP (addr, 1);
 325             }
 326           else if (GET_CODE (XEXP (addr, 1)) == REG)
 327             {
 328               if (reg1)
 329                 ireg = reg1, breg = XEXP (addr, 1), reg1 = 0;
 330               else
 331                 reg1 = XEXP (addr, 1);
 332             }
 333           else if (GET_CODE (XEXP (addr, 1)) == MULT)
 334             {
 335               if (ireg)
 336                 abort ();
 337               ireg = XEXP (addr, 1);
 338             }
 339           else
 340             abort ();
 341         }
 342       else
 343         abort ();
 344
 345       /* If REG1 is nonzero, figure out if it is a base or index register.  */
 346       if (reg1)
 347         {
 348           if (breg != 0 || (offset && GET_CODE (offset) == MEM))
 349             {
 350               if (ireg)
 351                 abort ();
 352               ireg = reg1;
 353             }
 354           else
 355             breg = reg1;
 356         }
 357
 358       if (offset != 0)
 359         output_address (offset);
 360
 361       if (breg != 0)
 362         fprintf (file, "(%s)", reg_names[REGNO (breg)]);
 363
 364       if (ireg != 0)
 365         {
 366           if (GET_CODE (ireg) == MULT)
 367             ireg = XEXP (ireg, 0);
 368           if (GET_CODE (ireg) != REG)
 369             abort ();
 370           fprintf (file, "[%s]", reg_names[REGNO (ireg)]);
 371         }
 372       break;
 373
 374     default:
 375       output_addr_const (file, addr);
 376     }
 377 }
 378 \f
 379 const char *
 380 rev_cond_name (rtx op)
 381 {
 382   switch (GET_CODE (op))
 383     {
 384     case EQ:
 385       return "neq";
 386     case NE:
 387       return "eql";
 388     case LT:
 389       return "geq";
 390     case LE:
 391       return "gtr";
 392     case GT:
 393       return "leq";
 394     case GE:
 395       return "lss";
 396     case LTU:
 397       return "gequ";
 398     case LEU:
 399       return "gtru";
 400     case GTU:
 401       return "lequ";
 402     case GEU:
 403       return "lssu";
 404
 405     default:
 406       abort ();
 407     }
 408 }
 409
 410 int
 411 vax_float_literal(register rtx c)
 412 {
 413   register enum machine_mode mode;
 414   REAL_VALUE_TYPE r, s;
 415   int i;
 416
 417   if (GET_CODE (c) != CONST_DOUBLE)
 418     return 0;
 419
 420   mode = GET_MODE (c);
 421
 422   if (c == const_tiny_rtx[(int) mode][0]
 423       || c == const_tiny_rtx[(int) mode][1]
 424       || c == const_tiny_rtx[(int) mode][2])
 425     return 1;
 426
 427   REAL_VALUE_FROM_CONST_DOUBLE (r, c);
 428
 429   for (i = 0; i < 7; i++)
 430     {
 431       int x = 1 << i;
 432       REAL_VALUE_FROM_INT (s, x, 0, mode);
 433
 434       if (REAL_VALUES_EQUAL (r, s))
 435         return 1;
 436       if (!exact_real_inverse (mode, &s))
 437         abort ();
 438       if (REAL_VALUES_EQUAL (r, s))
 439         return 1;
 440     }
 441   return 0;
 442 }
 443
 444
 445 /* Return the cost in cycles of a memory address, relative to register
 446    indirect.
 447
 448    Each of the following adds the indicated number of cycles:
 449
 450    1 - symbolic address
 451    1 - pre-decrement
 452    1 - indexing and/or offset(register)
 453    2 - indirect */
 454
 455
 456 static int
 457 vax_address_cost_1 (register rtx addr)
 458 {
 459   int reg = 0, indexed = 0, indir = 0, offset = 0, predec = 0;
 460   rtx plus_op0 = 0, plus_op1 = 0;
 461  restart:
 462   switch (GET_CODE (addr))
 463     {
 464     case PRE_DEC:
 465       predec = 1;
 466     case REG:
 467     case SUBREG:
 468     case POST_INC:
 469       reg = 1;
 470       break;
 471     case MULT:
 472       indexed = 1;      /* 2 on VAX 2 */
 473       break;
 474     case CONST_INT:
 475       /* byte offsets cost nothing (on a VAX 2, they cost 1 cycle) */
 476       if (offset == 0)
 477         offset = (unsigned)(INTVAL(addr)+128) > 256;
 478       break;
 479     case CONST:
 480     case SYMBOL_REF:
 481       offset = 1;       /* 2 on VAX 2 */
 482       break;
 483     case LABEL_REF:     /* this is probably a byte offset from the pc */
 484       if (offset == 0)
 485         offset = 1;
 486       break;
 487     case PLUS:
 488       if (plus_op0)
 489         plus_op1 = XEXP (addr, 0);
 490       else
 491         plus_op0 = XEXP (addr, 0);
 492       addr = XEXP (addr, 1);
 493       goto restart;
 494     case MEM:
 495       indir = 2;        /* 3 on VAX 2 */
 496       addr = XEXP (addr, 0);
 497       goto restart;
 498     default:
 499       break;
 500     }
 501
 502   /* Up to 3 things can be added in an address.  They are stored in
 503      plus_op0, plus_op1, and addr.  */
 504
 505   if (plus_op0)
 506     {
 507       addr = plus_op0;
 508       plus_op0 = 0;
 509       goto restart;
 510     }
 511   if (plus_op1)
 512     {
 513       addr = plus_op1;
 514       plus_op1 = 0;
 515       goto restart;
 516     }
 517   /* Indexing and register+offset can both be used (except on a VAX 2)
 518      without increasing execution time over either one alone.  */
 519   if (reg && indexed && offset)
 520     return reg + indir + offset + predec;
 521   return reg + indexed + indir + offset + predec;
 522 }
 523
 524 static int
 525 vax_address_cost (rtx x)
 526 {
 527   return (1 + (GET_CODE (x) == REG ? 0 : vax_address_cost_1 (x)));
 528 }
 529
 530 /* Cost of an expression on a VAX.  This version has costs tuned for the
 531    CVAX chip (found in the VAX 3 series) with comments for variations on
 532    other models.  */
 533
 534 static int
 535 vax_rtx_costs_1 (register rtx x, enum rtx_code code, enum rtx_code outer_code)
 536 {
 537   enum machine_mode mode = GET_MODE (x);
 538   register int c;
 539   int i = 0;                            /* may be modified in switch */
 540   const char *fmt = GET_RTX_FORMAT (code); /* may be modified in switch */
 541
 542   switch (code)
 543     {
 544       /* On a VAX, constants from 0..63 are cheap because they can use the
 545          1 byte literal constant format.  compare to -1 should be made cheap
 546          so that decrement-and-branch insns can be formed more easily (if
 547          the value -1 is copied to a register some decrement-and-branch
 548          patterns will not match).  */
 549     case CONST_INT:
 550       if (INTVAL (x) == 0)
 551         return 0;
 552       if (outer_code == AND)
 553         return ((unsigned HOST_WIDE_INT) ~INTVAL (x) <= 077) ? 1 : 2;
 554       if ((unsigned HOST_WIDE_INT) INTVAL (x) <= 077)
 555         return 1;
 556       if (outer_code == COMPARE && INTVAL (x) == -1)
 557         return 1;
 558       if (outer_code == PLUS && (unsigned HOST_WIDE_INT) -INTVAL (x) <= 077)
 559         return 1;
 560       /* FALLTHRU */
 561
 562     case CONST:
 563     case LABEL_REF:
 564     case SYMBOL_REF:
 565       return 3;
 566
 567     case CONST_DOUBLE:
 568       if (GET_MODE_CLASS (GET_MODE (x)) == MODE_FLOAT)
 569         return vax_float_literal (x) ? 5 : 8;
 570       else
 571         return (((CONST_DOUBLE_HIGH (x) == 0
 572                   && (unsigned HOST_WIDE_INT) CONST_DOUBLE_LOW (x) < 64)
 573                  || (outer_code == PLUS
 574                      && CONST_DOUBLE_HIGH (x) == -1             \
 575                      && (unsigned HOST_WIDE_INT)-CONST_DOUBLE_LOW (x) < 64))
 576                 ? 2 : 5);
 577
 578     case POST_INC:
 579       return 2;
 580     case PRE_DEC:
 581       return 3;
 582     case MULT:
 583       switch (mode)
 584         {
 585         case DFmode:
 586           c = 16;               /* 4 on VAX 9000 */
 587           break;
 588         case SFmode:
 589           c = 9;                /* 4 on VAX 9000, 12 on VAX 2 */
 590           break;
 591         case DImode:
 592           c = 16;               /* 6 on VAX 9000, 28 on VAX 2 */
 593           break;
 594         case SImode:
 595         case HImode:
 596         case QImode:
 597           c = 10;               /* 3-4 on VAX 9000, 20-28 on VAX 2 */
 598           break;
 599         default:
 600           return MAX_COST;      /* Mode is not supported.  */
 601         }
 602       break;
 603     case UDIV:
 604       if (mode != SImode)
 605         return MAX_COST;        /* Mode is not supported.  */
 606       c = 17;
 607       break;
 608     case DIV:
 609       if (mode == DImode)
 610         c = 30; /* highly variable */
 611       else if (mode == DFmode)
 612         /* divide takes 28 cycles if the result is not zero, 13 otherwise */
 613         c = 24;
 614       else
 615         c = 11;                 /* 25 on VAX 2 */
 616       break;
 617     case MOD:
 618       c = 23;
 619       break;
 620     case UMOD:
 621       if (mode != SImode)
 622         return MAX_COST;        /* Mode is not supported.  */
 623       c = 29;
 624       break;
 625     case FLOAT:
 626       c = 6 + (mode == DFmode) + (GET_MODE (XEXP (x, 0)) != SImode);
 627       /* 4 on VAX 9000 */
 628       break;
 629     case FIX:
 630       c = 7;                    /* 17 on VAX 2 */
 631       break;
 632     case ASHIFT:
 633     case LSHIFTRT:
 634     case ASHIFTRT:
 635       if (mode == DImode)
 636         c = 12;
 637       else
 638         c = 10;                 /* 6 on VAX 9000 */
 639       break;
 640     case ROTATE:
 641     case ROTATERT:
 642       c = 6;                    /* 5 on VAX 2, 4 on VAX 9000 */
 643       if (GET_CODE (XEXP (x, 1)) == CONST_INT)
 644         fmt = "e";      /* all constant rotate counts are short */
 645       break;
 646     case PLUS:
 647       /* Check for small negative integer operand: subl2 can be used with
 648          a short positive constant instead.  */
 649       if (GET_CODE (XEXP (x, 1)) == CONST_INT)
 650         if ((unsigned)(INTVAL (XEXP (x, 1)) + 63) < 127)
 651           fmt = "e";
 652     case MINUS:
 653       c = (mode == DFmode) ? 13 : 8;    /* 6/8 on VAX 9000, 16/15 on VAX 2 */
 654     case IOR:
 655     case XOR:
 656       c = 3;
 657       break;
 658     case AND:
 659       /* AND is special because the first operand is complemented.  */
 660       c = 3;
 661       if (GET_CODE (XEXP (x, 0)) == CONST_INT)
 662         {
 663           if ((unsigned)~INTVAL (XEXP (x, 0)) > 63)
 664             c = 4;
 665           fmt = "e";
 666           i = 1;
 667         }
 668       break;
 669     case NEG:
 670       if (mode == DFmode)
 671         return 9;
 672       else if (mode == SFmode)
 673         return 6;
 674       else if (mode == DImode)
 675         return 4;
 676     case NOT:
 677       return 2;
 678     case ZERO_EXTRACT:
 679     case SIGN_EXTRACT:
 680       c = 15;
 681       break;
 682     case MEM:
 683       if (mode == DImode || mode == DFmode)
 684         c = 5;                          /* 7 on VAX 2 */
 685       else
 686         c = 3;                          /* 4 on VAX 2 */
 687       x = XEXP (x, 0);
 688       if (GET_CODE (x) == REG || GET_CODE (x) == POST_INC)
 689         return c;
 690       return c + vax_address_cost_1 (x);
 691     default:
 692       c = 3;
 693       break;
 694     }
 695
 696   /* Now look inside the expression.  Operands which are not registers or
 697      short constants add to the cost.
 698
 699      FMT and I may have been adjusted in the switch above for instructions
 700      which require special handling */
 701
 702   while (*fmt++ == 'e')
 703     {
 704       register rtx op = XEXP (x, i++);
 705       code = GET_CODE (op);
 706
 707       /* A NOT is likely to be found as the first operand of an AND
 708          (in which case the relevant cost is of the operand inside
 709          the not) and not likely to be found anywhere else.  */
 710       if (code == NOT)
 711         op = XEXP (op, 0), code = GET_CODE (op);
 712
 713       switch (code)
 714         {
 715         case CONST_INT:
 716           if ((unsigned)INTVAL (op) > 63 && GET_MODE (x) != QImode)
 717             c += 1;             /* 2 on VAX 2 */
 718           break;
 719         case CONST:
 720         case LABEL_REF:
 721         case SYMBOL_REF:
 722           c += 1;               /* 2 on VAX 2 */
 723           break;
 724         case CONST_DOUBLE:
 725           if (GET_MODE_CLASS (GET_MODE (op)) == MODE_FLOAT)
 726             {
 727               /* Registers are faster than floating point constants -- even
 728                  those constants which can be encoded in a single byte.  */
 729               if (vax_float_literal (op))
 730                 c++;
 731               else
 732                 c += (GET_MODE (x) == DFmode) ? 3 : 2;
 733             }
 734           else
 735             {
 736               if (CONST_DOUBLE_HIGH (op) != 0
 737                   || (unsigned)CONST_DOUBLE_LOW (op) > 63)
 738                 c += 2;
 739             }
 740           break;
 741         case MEM:
 742           c += 1;               /* 2 on VAX 2 */
 743           if (GET_CODE (XEXP (op, 0)) != REG)
 744             c += vax_address_cost_1 (XEXP (op, 0));
 745           break;
 746         case REG:
 747         case SUBREG:
 748           break;
 749         default:
 750           c += 1;
 751           break;
 752         }
 753     }
 754   return c;
 755 }
 756
 757 static bool
 758 vax_rtx_costs (rtx x, int code, int outer_code, int * total)
 759 {
 760   *total = vax_rtx_costs_1 (x, code, outer_code);
 761   return true;
 762 }
 763 \f
 764 /* Output code to add DELTA to the first argument, and then jump to FUNCTION.
 765    Used for C++ multiple inheritance.
 766         .mask   ^m<r2,r3,r4,r5,r6,r7,r8,r9,r10,r11>  #conservative entry mask
 767         addl2   $DELTA, 4(ap)   #adjust first argument
 768         jmp     FUNCTION+2      #jump beyond FUNCTION's entry mask
 769 */
 770
 771 static void
 772 vax_output_mi_thunk (FILE * file,
 773                      tree thunk ATTRIBUTE_UNUSED,
 774                      HOST_WIDE_INT delta,
 775                      HOST_WIDE_INT vcall_offset ATTRIBUTE_UNUSED,
 776                      tree function)
 777 {
 778   fprintf (file, "\t.word 0x0ffc\n\taddl2 $" HOST_WIDE_INT_PRINT_DEC, delta);
 779   asm_fprintf (file, ",4(%Rap)\n");
 780   fprintf (file, "\tjmp ");
 781   assemble_name (file,  XSTR (XEXP (DECL_RTL (function), 0), 0));
 782   fprintf (file, "+2\n");
 783 }
 784 \f
 785 static rtx
 786 vax_struct_value_rtx (tree fntype ATTRIBUTE_UNUSED,
 787                       int incoming ATTRIBUTE_UNUSED)
 788 {
 789   return gen_rtx_REG (Pmode, VAX_STRUCT_VALUE_REGNUM);
 790 }