[AArch64] Properly cost MNEG/[SU]MNEGL patterns

	* config/aarch64/aarch64.c (aarch64_rtx_mult_cost): Handle MNEG
	and [SU]MNEGL patterns.

From-SVN: r222627

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 4eacfc9..8cf8854 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,10 @@
 2015-04-30  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
+       * config/aarch64/aarch64.c (aarch64_rtx_mult_cost): Handle MNEG
+       and [SU]MNEGL patterns.
+
+2015-04-30  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
+
        * config/aarch64/aarch64.c (aarch64_shift_p): New function.
        (aarch64_rtx_mult_cost): Update comment to reflect that it also handles
        combined arithmetic-shift ops.  Properly handle all shift and extend

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 3be7b41..7d7f890 100644 (file)
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -5229,6 +5229,15 @@ aarch64_rtx_mult_cost (rtx x, int code, int outer, bool speed)
          return cost;
        }
 
+      /* MNEG or [US]MNEGL.  Extract the NEG operand and indicate that it's a
+        compound and let the below cases handle it.  After all, MNEG is a
+        special-case alias of MSUB.  */
+      if (GET_CODE (op0) == NEG)
+       {
+         op0 = XEXP (op0, 0);
+         compound_p = true;
+       }
+
       /* Integer multiplies or FMAs have zero/sign extending variants.  */
       if ((GET_CODE (op0) == ZERO_EXTEND
           && GET_CODE (op1) == ZERO_EXTEND)
@@ -5241,7 +5250,7 @@ aarch64_rtx_mult_cost (rtx x, int code, int outer, bool speed)
          if (speed)
            {
              if (compound_p)
-               /* MADD/SMADDL/UMADDL.  */
+               /* SMADDL/UMADDL/UMSUBL/SMSUBL.  */
                cost += extra_cost->mult[0].extend_add;
              else
                /* MUL/SMULL/UMULL.  */
@@ -5251,7 +5260,7 @@ aarch64_rtx_mult_cost (rtx x, int code, int outer, bool speed)
          return cost;
        }
 
-      /* This is either an integer multiply or an FMA.  In both cases
+      /* This is either an integer multiply or a MADD.  In both cases
         we want to recurse and cost the operands.  */
       cost += rtx_cost (op0, MULT, 0, speed)
              + rtx_cost (op1, MULT, 1, speed);
@@ -5259,7 +5268,7 @@ aarch64_rtx_mult_cost (rtx x, int code, int outer, bool speed)
       if (speed)
        {
          if (compound_p)
-           /* MADD.  */
+           /* MADD/MSUB.  */
            cost += extra_cost->mult[mode == DImode].add;
          else
            /* MUL.  */