0053-tcg-Optimize-two-address-commutative-operations.patch

   1 From af2bf6bcc6614622c87d28e9d763b57408c17500 Mon Sep 17 00:00:00 2001
   2 From: Richard Henderson <rth@twiddle.net>
   3 Date: Fri, 21 Sep 2012 10:13:38 -0700
   4 Subject: [PATCH] tcg: Optimize two-address commutative operations
   5
   6 While swapping constants to the second operand, swap
   7 sources matching destinations to the first operand.
   8
   9 Signed-off-by: Richard Henderson <rth@twiddle.net>
  10 Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
  11 Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
  12 ---
  13  tcg/optimize.c | 15 ++++++++++++++-
  14  1 file changed, 14 insertions(+), 1 deletion(-)
  15
  16 diff --git a/tcg/optimize.c b/tcg/optimize.c
  17 index 26038a6..1be7631 100644
  18 --- a/tcg/optimize.c
  19 +++ b/tcg/optimize.c
  20 @@ -334,6 +334,8 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
  21      const TCGOpDef *def;
  22      TCGArg *gen_args;
  23      TCGArg tmp;
  24 +    TCGCond cond;
  25 +
  26      /* Array VALS has an element for each temp.
  27         If this temp holds a constant then its value is kept in VALS' element.
  28         If this temp is a copy of other ones then this equivalence class'
  29 @@ -395,13 +397,24 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
  30              }
  31              break;
  32          CASE_OP_32_64(movcond):
  33 +            cond = args[5];
  34              if (temps[args[1]].state == TCG_TEMP_CONST
  35                  && temps[args[2]].state != TCG_TEMP_CONST) {
  36                  tmp = args[1];
  37                  args[1] = args[2];
  38                  args[2] = tmp;
  39 -                args[5] = tcg_swap_cond(args[5]);
  40 +                cond = tcg_swap_cond(cond);
  41 +            }
  42 +            /* For movcond, we canonicalize the "false" input reg to match
  43 +               the destination reg so that the tcg backend can implement
  44 +               a "move if true" operation.  */
  45 +            if (args[0] == args[3]) {
  46 +                tmp = args[3];
  47 +                args[3] = args[4];
  48 +                args[4] = tmp;
  49 +                cond = tcg_invert_cond(cond);
  50              }
  51 +            args[5] = cond;
  52          default:
  53              break;
  54          }
  55 --
  56 1.7.12.1
  57