(expand_divmod): prefer divmod in same mode over div in wider mode.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@13638 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/expmed.c b/gcc/expmed.c
index 4b569b1..65fb007 100644 (file)
--- a/gcc/expmed.c
+++ b/gcc/expmed.c
@@ -3661,11 +3661,18 @@ expand_divmod (rem_flag, code, mode, op0, op1, target, unsignedp)
            return gen_lowpart (mode, remainder);
        }
 
-      /* Produce the quotient.  */
-      /* Try a quotient insn, but not a library call.  */
-      quotient = sign_expand_binop (compute_mode, udiv_optab, sdiv_optab,
-                                   op0, op1, rem_flag ? NULL_RTX : target,
-                                   unsignedp, OPTAB_WIDEN);
+      /* Produce the quotient.  Try a quotient insn, but not a library call.
+        If we have a divmod in this mode, use it in preference to widening
+        the div (for this test we assume it will not fail). Note that optab2
+        is set to the one of the two optabs that the call below will use.  */
+      quotient
+       = sign_expand_binop (compute_mode, udiv_optab, sdiv_optab,
+                            op0, op1, rem_flag ? NULL_RTX : target,
+                            unsignedp,
+                            ((optab2->handlers[(int) compute_mode].insn_code
+                              != CODE_FOR_nothing)
+                             ? OPTAB_DIRECT : OPTAB_WIDEN));
+
       if (quotient == 0)
        {
          /* No luck there.  Try a quotient-and-remainder insn,