(adddi3, subdi3, negdi2): Add constraints so output reg does not

overlap one reg with one of the inputs.

From-SVN: r10325

gcc/config/rs6000/rs6000.md

@@ -3510,7 +3510,11 @@
   [(set_attr "type" "fp")])
 
 ;; Define the DImode operations that can be done in a small number
-;; of instructions.
+;; of instructions.  The & constraints are to prevent the register
+;; allocator from allocating registers that overlap with the inputs
+;; (for example, having an input in 7,8 and an output in 6,7).  We
+;; also allow for the the output being the same as one of the inputs.
+
 (define_expand "adddi3"
   [(set (match_operand:DI 0 "gpc_reg_operand" "")
 	(plus:DI (match_operand:DI 1 "gpc_reg_operand" "")
@@ -3524,19 +3528,21 @@
 }")
 
 (define_insn ""
-  [(set (match_operand:DI 0 "gpc_reg_operand" "=r,r")
-	(plus:DI (match_operand:DI 1 "gpc_reg_operand" "%r,r")
-		 (match_operand:DI 2 "reg_or_short_operand" "r,I")))]
+  [(set (match_operand:DI 0 "gpc_reg_operand" "=&r,&r,r,r")
+	(plus:DI (match_operand:DI 1 "gpc_reg_operand" "%r,r,0,0")
+		 (match_operand:DI 2 "reg_or_short_operand" "r,I,r,I")))]
   "TARGET_POWER && ! TARGET_POWERPC64"
   "@
    {a|addc} %L0,%L1,%L2\;{ae|adde} %0,%1,%2
+   {ai|addic} %L0,%L1,%2\;{a%G2e|add%G2e} %0,%1
+   {a|addc} %L0,%L1,%L2\;{ae|adde} %0,%1,%2
    {ai|addic} %L0,%L1,%2\;{a%G2e|add%G2e} %0,%1"
   [(set_attr "length" "8")])
 
 (define_insn ""
-  [(set (match_operand:DI 0 "gpc_reg_operand" "=r")
-	(plus:DI (match_operand:DI 1 "gpc_reg_operand" "%r")
-		 (match_operand:DI 2 "gpc_reg_operand" "r")))]
+  [(set (match_operand:DI 0 "gpc_reg_operand" "=&r,r")
+	(plus:DI (match_operand:DI 1 "gpc_reg_operand" "%r,0")
+		 (match_operand:DI 2 "gpc_reg_operand" "r,r")))]
   "! TARGET_POWER && ! TARGET_POWERPC64"
   "*
 {
@@ -3547,9 +3553,9 @@
   [(set_attr "length" "8")])
 
 (define_expand "subdi3"
-  [(set (match_operand:DI 0 "gpc_reg_operand" "=r,r")
-	(minus:DI (match_operand:DI 1 "reg_or_short_operand" "r,I")
-		  (match_operand:DI 2 "gpc_reg_operand" "r,r")))]
+  [(set (match_operand:DI 0 "gpc_reg_operand" "")
+	(minus:DI (match_operand:DI 1 "reg_or_short_operand" "")
+		  (match_operand:DI 2 "gpc_reg_operand" "")))]
   ""
   "
 {
@@ -3559,19 +3565,21 @@
 }")
 
 (define_insn ""
-  [(set (match_operand:DI 0 "gpc_reg_operand" "=r,r")
-	(minus:DI (match_operand:DI 1 "reg_or_short_operand" "r,I")
-		  (match_operand:DI 2 "gpc_reg_operand" "r,r")))]
+  [(set (match_operand:DI 0 "gpc_reg_operand" "=&r,&r,r,r")
+	(minus:DI (match_operand:DI 1 "reg_or_short_operand" "r,I,0,r")
+		  (match_operand:DI 2 "gpc_reg_operand" "r,r,r,0")))]
   "TARGET_POWER && ! TARGET_POWERPC64"
   "@
    {sf|subfc} %L0,%L2,%L1\;{sfe|subfe} %0,%2,%1
+   {sfi|subfic} %L0,%L2,%1\;{sf%G1e|subf%G1e} %0,%2
+   {sf|subfc} %L0,%L2,%L1\;{sfe|subfe} %0,%2,%1
    {sfi|subfic} %L0,%L2,%1\;{sf%G1e|subf%G1e} %0,%2"
   [(set_attr "length" "8")])
 
 (define_insn ""
-  [(set (match_operand:DI 0 "gpc_reg_operand" "=r")
-	(minus:DI (match_operand:DI 1 "gpc_reg_operand" "r")
-		  (match_operand:DI 2 "gpc_reg_operand" "r")))]
+  [(set (match_operand:DI 0 "gpc_reg_operand" "=&r,r,r")
+	(minus:DI (match_operand:DI 1 "gpc_reg_operand" "r,0,r")
+		  (match_operand:DI 2 "gpc_reg_operand" "r,r,0")))]
   "! TARGET_POWER && ! TARGET_POWERPC64"
   "*
 {
@@ -3588,8 +3596,8 @@
   "")
 
 (define_insn ""
-  [(set (match_operand:DI 0 "gpc_reg_operand" "=r")
-	(neg:DI (match_operand:DI 1 "gpc_reg_operand" "r")))]
+  [(set (match_operand:DI 0 "gpc_reg_operand" "=&r,r")
+	(neg:DI (match_operand:DI 1 "gpc_reg_operand" "r,0")))]
   "! TARGET_POWERPC64"
   "*
 {