entered into RCS

From-SVN: r1024

gcc/config/m68k/m68k.md

@@ -1267,11 +1267,13 @@
 
 ;; Patterns to recognize zero-extend insns produced by the combiner.
 ;; We don't allow both operands in memory, because of aliasing problems.
+;; Explicitly disallow two memory operands via the condition since reloading
+;; of this case will result in worse code than the uncombined patterns.
 
 (define_insn ""
   [(set (match_operand:SI 0 "general_operand" "=do<>,d<")
 	(zero_extend:SI (match_operand:HI 1 "nonimmediate_operand" "r,m")))]
-  ""
+  "GET_CODE (operands[0]) != MEM || GET_CODE (operands[1]) != MEM"
   "*
 {
   if (DATA_REG_P (operands[0]))
@@ -1300,7 +1302,7 @@
 (define_insn ""
   [(set (match_operand:HI 0 "general_operand" "=do<>,d")
 	(zero_extend:HI (match_operand:QI 1 "nonimmediate_operand" "d,m")))]
-  ""
+  "GET_CODE (operands[0]) != MEM || GET_CODE (operands[1]) != MEM"
   "*
 {
   if (DATA_REG_P (operands[0]))
@@ -1340,7 +1342,7 @@
 (define_insn ""
   [(set (match_operand:SI 0 "general_operand" "=do<>,d")
 	(zero_extend:SI (match_operand:QI 1 "nonimmediate_operand" "d,m")))]
-  ""
+  "GET_CODE (operands[0]) != MEM || GET_CODE (operands[1]) != MEM"
   "*
 {
   if (DATA_REG_P (operands[0]))