gcc/config/nds32/nds32-cost.c

   1 /* Subroutines used for calculate rtx costs of Andes NDS32 cpu for GNU compiler
   2    Copyright (C) 2012-2015 Free Software Foundation, Inc.
   3    Contributed by Andes Technology Corporation.
   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 /* ------------------------------------------------------------------------ */
  22
  23 #include "config.h"
  24 #include "system.h"
  25 #include "coretypes.h"
  26 #include "tm.h"
  27 #include "tree.h"
  28 #include "stor-layout.h"
  29 #include "varasm.h"
  30 #include "calls.h"
  31 #include "rtl.h"
  32 #include "regs.h"
  33 #include "hard-reg-set.h"
  34 #include "insn-config.h"        /* Required by recog.h.  */
  35 #include "conditions.h"
  36 #include "output.h"
  37 #include "insn-attr.h"          /* For DFA state_t.  */
  38 #include "insn-codes.h"         /* For CODE_FOR_xxx.  */
  39 #include "reload.h"             /* For push_reload().  */
  40 #include "flags.h"
  41 #include "hashtab.h"
  42 #include "hash-set.h"
  43 #include "vec.h"
  44 #include "machmode.h"
  45 #include "input.h"
  46 #include "function.h"
  47 #include "expr.h"
  48 #include "recog.h"
  49 #include "diagnostic-core.h"
  50 #include "dominance.h"
  51 #include "cfg.h"
  52 #include "cfgrtl.h"
  53 #include "cfganal.h"
  54 #include "lcm.h"
  55 #include "cfgbuild.h"
  56 #include "cfgcleanup.h"
  57 #include "predict.h"
  58 #include "basic-block.h"
  59 #include "df.h"
  60 #include "tm_p.h"
  61 #include "tm-constrs.h"
  62 #include "optabs.h"             /* For GEN_FCN.  */
  63 #include "target.h"
  64 #include "target-def.h"
  65 #include "langhooks.h"          /* For add_builtin_function().  */
  66 #include "ggc.h"
  67 #include "builtins.h"
  68
  69 /* ------------------------------------------------------------------------ */
  70
  71 bool
  72 nds32_rtx_costs_impl (rtx x,
  73                       int code,
  74                       int outer_code,
  75                       int opno ATTRIBUTE_UNUSED,
  76                       int *total,
  77                       bool speed)
  78 {
  79   /* According to 'speed', goto suitable cost model section.  */
  80   if (speed)
  81     goto performance_cost;
  82   else
  83     goto size_cost;
  84
  85
  86 performance_cost:
  87   /* This is section for performance cost model.  */
  88
  89   /* In gcc/rtl.h, the default value of COSTS_N_INSNS(N) is N*4.
  90      We treat it as 4-cycle cost for each instruction
  91      under performance consideration.  */
  92   switch (code)
  93     {
  94     case SET:
  95       /* For 'SET' rtx, we need to return false
  96          so that it can recursively calculate costs.  */
  97       return false;
  98
  99     case USE:
 100       /* Used in combine.c as a marker.  */
 101       *total = 0;
 102       break;
 103
 104     case MULT:
 105       *total = COSTS_N_INSNS (1);
 106       break;
 107
 108     case DIV:
 109     case UDIV:
 110     case MOD:
 111     case UMOD:
 112       *total = COSTS_N_INSNS (7);
 113       break;
 114
 115     default:
 116       *total = COSTS_N_INSNS (1);
 117       break;
 118     }
 119
 120   return true;
 121
 122
 123 size_cost:
 124   /* This is section for size cost model.  */
 125
 126   /* In gcc/rtl.h, the default value of COSTS_N_INSNS(N) is N*4.
 127      We treat it as 4-byte cost for each instruction
 128      under code size consideration.  */
 129   switch (code)
 130     {
 131     case SET:
 132       /* For 'SET' rtx, we need to return false
 133          so that it can recursively calculate costs.  */
 134       return false;
 135
 136     case USE:
 137       /* Used in combine.c as a marker.  */
 138       *total = 0;
 139       break;
 140
 141     case CONST_INT:
 142       /* All instructions involving constant operation
 143          need to be considered for cost evaluation.  */
 144       if (outer_code == SET)
 145         {
 146           /* (set X imm5s), use movi55, 2-byte cost.
 147              (set X imm20s), use movi, 4-byte cost.
 148              (set X BIG_INT), use sethi/ori, 8-byte cost.  */
 149           if (satisfies_constraint_Is05 (x))
 150             *total = COSTS_N_INSNS (1) - 2;
 151           else if (satisfies_constraint_Is20 (x))
 152             *total = COSTS_N_INSNS (1);
 153           else
 154             *total = COSTS_N_INSNS (2);
 155         }
 156       else if (outer_code == PLUS || outer_code == MINUS)
 157         {
 158           /* Possible addi333/subi333 or subi45/addi45, 2-byte cost.
 159              General case, cost 1 instruction with 4-byte.  */
 160           if (satisfies_constraint_Iu05 (x))
 161             *total = COSTS_N_INSNS (1) - 2;
 162           else
 163             *total = COSTS_N_INSNS (1);
 164         }
 165       else if (outer_code == ASHIFT)
 166         {
 167           /* Possible slli333, 2-byte cost.
 168              General case, cost 1 instruction with 4-byte.  */
 169           if (satisfies_constraint_Iu03 (x))
 170             *total = COSTS_N_INSNS (1) - 2;
 171           else
 172             *total = COSTS_N_INSNS (1);
 173         }
 174       else if (outer_code == ASHIFTRT || outer_code == LSHIFTRT)
 175         {
 176           /* Possible srai45 or srli45, 2-byte cost.
 177              General case, cost 1 instruction with 4-byte.  */
 178           if (satisfies_constraint_Iu05 (x))
 179             *total = COSTS_N_INSNS (1) - 2;
 180           else
 181             *total = COSTS_N_INSNS (1);
 182         }
 183       else
 184         {
 185           /* For other cases, simply set it 4-byte cost.  */
 186           *total = COSTS_N_INSNS (1);
 187         }
 188       break;
 189
 190     case CONST_DOUBLE:
 191       /* It requires high part and low part processing, set it 8-byte cost.  */
 192       *total = COSTS_N_INSNS (2);
 193       break;
 194
 195     default:
 196       /* For other cases, generally we set it 4-byte cost
 197          and stop resurively traversing.  */
 198       *total = COSTS_N_INSNS (1);
 199       break;
 200     }
 201
 202   return true;
 203 }
 204
 205 int
 206 nds32_address_cost_impl (rtx address,
 207                          machine_mode mode ATTRIBUTE_UNUSED,
 208                          addr_space_t as ATTRIBUTE_UNUSED,
 209                          bool speed)
 210 {
 211   rtx plus0, plus1;
 212   enum rtx_code code;
 213
 214   code = GET_CODE (address);
 215
 216   /* According to 'speed', goto suitable cost model section.  */
 217   if (speed)
 218     goto performance_cost;
 219   else
 220     goto size_cost;
 221
 222 performance_cost:
 223   /* This is section for performance cost model.  */
 224
 225   /* FALLTHRU, currently we use same cost model as size_cost.  */
 226
 227 size_cost:
 228   /* This is section for size cost model.  */
 229
 230   switch (code)
 231     {
 232     case POST_MODIFY:
 233     case POST_INC:
 234     case POST_DEC:
 235       /* We encourage that rtx contains
 236          POST_MODIFY/POST_INC/POST_DEC behavior.  */
 237       return 0;
 238
 239     case SYMBOL_REF:
 240       /* We can have gp-relative load/store for symbol_ref.
 241          Have it 4-byte cost.  */
 242       return COSTS_N_INSNS (1);
 243
 244     case CONST:
 245       /* It is supposed to be the pattern (const (plus symbol_ref const_int)).
 246          Have it 4-byte cost.  */
 247       return COSTS_N_INSNS (1);
 248
 249     case REG:
 250       /* Simply return 4-byte costs.  */
 251       return COSTS_N_INSNS (1);
 252
 253     case PLUS:
 254       /* We do not need to check if the address is a legitimate address,
 255          because this hook is never called with an invalid address.
 256          But we better check the range of
 257          const_int value for cost, if it exists.  */
 258       plus0 = XEXP (address, 0);
 259       plus1 = XEXP (address, 1);
 260
 261       if (REG_P (plus0) && CONST_INT_P (plus1))
 262         {
 263           /* If it is possible to be lwi333/swi333 form,
 264              make it 2-byte cost.  */
 265           if (satisfies_constraint_Iu05 (plus1))
 266             return (COSTS_N_INSNS (1) - 2);
 267           else
 268             return COSTS_N_INSNS (1);
 269         }
 270
 271       /* For other 'plus' situation, make it cost 4-byte.  */
 272       return COSTS_N_INSNS (1);
 273
 274     default:
 275       break;
 276     }
 277
 278   return COSTS_N_INSNS (4);
 279 }
 280
 281 /* ------------------------------------------------------------------------ */