Don't use shifts for extendsidi2

From-SVN: r13008

gcc/config/mips/mips.md

@@ -2508,35 +2508,19 @@ move\\t%0,%z4\\n\\
 ;; Extension insns.
 ;; Those for integer source operand are ordered widest source type first.
 
-(define_expand "extendsidi2"
-  [(set (match_operand:DI 0 "register_operand" "")
-	(sign_extend:DI (match_operand:SI 1 "nonimmediate_operand" "")))]
-  "TARGET_64BIT"
-  "
-{
-  if (optimize && GET_CODE (operands[1]) == MEM)
-    operands[1] = force_not_mem (operands[1]);
-
-  if (GET_CODE (operands[1]) != MEM)
-    {
-      rtx op1   = gen_lowpart (DImode, operands[1]);
-      rtx temp  = gen_reg_rtx (DImode);
-      rtx shift = gen_rtx (CONST_INT, VOIDmode, 32);
+;; In 64 bit mode, 32 bit values in general registers are always
+;; correctly sign extended.  That means that if the target is a
+;; general register, we can sign extend from SImode to DImode just by
+;; doing a move.
 
-      emit_insn (gen_ashldi3 (temp, op1, shift));
-      emit_insn (gen_ashrdi3 (operands[0], temp, shift));
-      DONE;
-    }
-}")
-
-(define_insn "extendsidi2_internal"
-  [(set (match_operand:DI 0 "register_operand" "=d,d")
-	(sign_extend:DI (match_operand:SI 1 "memory_operand" "R,m")))]
+(define_insn "extendsidi2"
+  [(set (match_operand:DI 0 "register_operand" "=d,d,d")
+	(sign_extend:DI (match_operand:SI 1 "nonimmediate_operand" "d,R,m")))]
   "TARGET_64BIT"
   "* return mips_move_1word (operands, insn, FALSE);"
-  [(set_attr "type"	"load")
+  [(set_attr "type"	"move,load,load")
    (set_attr "mode"	"DI")
-   (set_attr "length"	"1,2")])
+   (set_attr "length"	"1,1,2")])
 
 ;; These patterns originally accepted general_operands, however, slightly
 ;; better code is generated by only accepting register_operands, and then