(expand_binop): If, e.g., mulqi3 doesn't exist, try mulqihi3.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@1932 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/optabs.c b/gcc/optabs.c
index bdc69ca..cee0762 100644 (file)
--- a/gcc/optabs.c
+++ b/gcc/optabs.c
@@ -413,15 +413,39 @@ expand_binop (mode, binoptab, op0, op1, target, unsignedp, methods)
        delete_insns_since (last);
     }
 
+  /* If this is a multiply, see if we can do a widening operation that
+     takes operands of this mode and makes a wider mode.  */
+
+  if (binoptab == smul_optab && GET_MODE_WIDER_MODE (mode) != VOIDmode
+      && (((unsignedp ? umul_widen_optab : smul_widen_optab)
+          ->handlers[(int) GET_MODE_WIDER_MODE (mode)].insn_code)
+         != CODE_FOR_nothing))
+    {
+      temp = expand_binop (GET_MODE_WIDER_MODE (mode),
+                          unsignedp ? umul_widen_optab : smul_widen_optab,
+                          op0, op1, 0, unsignedp, OPTAB_DIRECT);
+
+      if (GET_MODE_CLASS (mode) == MODE_INT)
+       return gen_lowpart (mode, temp);
+      else
+       return convert_to_mode (mode, temp, unsignedp);
+    }
+
   /* Look for a wider mode of the same class for which we think we
-     can open-code the operation.  */
+     can open-code the operation.  Check for a widening multiply at the
+     wider mode as well.  */
 
   if ((class == MODE_INT || class == MODE_FLOAT || class == MODE_COMPLEX_FLOAT)
       && mode != OPTAB_DIRECT && mode != OPTAB_LIB)
     for (wider_mode = GET_MODE_WIDER_MODE (mode); wider_mode != VOIDmode;
         wider_mode = GET_MODE_WIDER_MODE (wider_mode))
       {
-       if (binoptab->handlers[(int) wider_mode].insn_code != CODE_FOR_nothing)
+       if (binoptab->handlers[(int) wider_mode].insn_code != CODE_FOR_nothing
+           || (binoptab == smul_optab
+               && GET_MODE_WIDER_MODE (wider_mode) != VOIDmode
+               && (((unsignedp ? umul_widen_optab : smul_widen_optab)
+                    ->handlers[(int) GET_MODE_WIDER_MODE (wider_mode)].insn_code)
+                   != CODE_FOR_nothing)))
          {
            rtx xop0 = op0, xop1 = op1;
            int no_extend = 0;