predicates.md (scc_rev_comparison_operator): New.

	* config/rs6000/predicates.md (scc_rev_comparison_operator): New.
	* config/rs6000/rs6000.md (*isel_reversed_signed_<mode>): New.
	(*isel_reversed_unsigned_<mode>): New.
	* config/rs6000/rs6000.c (output_isel): Accept GE/GEU/LE/LEU/NE
	as valid comparisons and adjust operands and output appropriately.
	(rs6000_rtx_costs) <CONST_INT>: Accept NE as a cost-0 outer_code.

From-SVN: r165395

4 files changed, 55 insertions, 2 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 14e4cde..9b72153 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2010-10-12  Nathan Froyd  <froydnj@codesourcery.com>
+
+	* config/rs6000/predicates.md (scc_rev_comparison_operator): New.
+	* config/rs6000/rs6000.md (*isel_reversed_signed_<mode>): New.
+	(*isel_reversed_unsigned_<mode>): New.
+	* config/rs6000/rs6000.c (output_isel): Accept GE/GEU/LE/LEU/NE
+	as valid comparisons and adjust operands and output appropriately.
+	(rs6000_rtx_costs) <CONST_INT>: Accept NE as a cost-0 outer_code.
+
 2010-10-12  Chung-Lin Tang  <cltang@codesourcery.com>
 
 	* config/arm/arm.h (ARM_EXPAND_ALIGNMENT): Rename from
diff --git a/gcc/config/rs6000/predicates.md b/gcc/config/rs6000/predicates.md
index c94af46..81ac68a 100644
--- a/gcc/config/rs6000/predicates.md
+++ b/gcc/config/rs6000/predicates.md
@@ -903,6 +903,12 @@
   (and (match_operand 0 "branch_comparison_operator")
        (match_code "eq,lt,gt,ltu,gtu,unordered")))
 
+;; Return 1 if OP is a comparison operation whose inverse would be valid for
+;; an SCC insn.
+(define_predicate "scc_rev_comparison_operator"
+  (and (match_operand 0 "branch_comparison_operator")
+       (match_code "ne,le,ge,leu,geu,ordered")))
+
 ;; Return 1 if OP is a comparison operation that is valid for a branch
 ;; insn, which is true if the corresponding bit in the CC register is set.
 (define_predicate "branch_positive_comparison_operator"
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index cd1c8cc..d7377a5 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -17159,7 +17159,13 @@ output_isel (rtx *operands)
 
   code = GET_CODE (operands[1]);
 
-  gcc_assert (!(code == GE || code == GEU || code == LE || code == LEU || code == NE));
+  if (code == GE || code == GEU || code == LE || code == LEU || code == NE)
+    {
+      gcc_assert (GET_CODE (operands[2]) == REG
+		  && GET_CODE (operands[3]) == REG);
+      PUT_CODE (operands[1], reverse_condition (code));
+      return "isel %0,%3,%2,%j1";
+    }
 
   return "isel %0,%2,%3,%j1";
 }
@@ -25731,7 +25737,7 @@ rs6000_rtx_costs (rtx x, int code, int outer_code, int *total,
 	  || (outer_code == COMPARE
 	      && (satisfies_constraint_I (x)
 		  || satisfies_constraint_K (x)))
-	  || (outer_code == EQ
+	  || ((outer_code == EQ || outer_code == NE)
 	      && (satisfies_constraint_I (x)
 		  || satisfies_constraint_K (x)
 		  || (mode == SImode
diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
index 23fde85..9fa2ff1 100644
--- a/gcc/config/rs6000/rs6000.md
+++ b/gcc/config/rs6000/rs6000.md
@@ -6126,6 +6126,38 @@
   [(set_attr "type" "isel")
    (set_attr "length" "4")])
 
+;; These patterns can be useful for combine; they let combine know that
+;; isel can handle reversed comparisons so long as the operands are
+;; registers.
+
+(define_insn "*isel_reversed_signed_<mode>"
+  [(set (match_operand:GPR 0 "gpc_reg_operand" "=r")
+	(if_then_else:GPR
+	 (match_operator 1 "scc_rev_comparison_operator"
+			 [(match_operand:CC 4 "cc_reg_operand" "y")
+			  (const_int 0)])
+	 (match_operand:GPR 2 "gpc_reg_operand" "b")
+	 (match_operand:GPR 3 "gpc_reg_operand" "b")))]
+  "TARGET_ISEL<sel>"
+  "*
+{ return output_isel (operands); }"
+  [(set_attr "type" "isel")
+   (set_attr "length" "4")])
+
+(define_insn "*isel_reversed_unsigned_<mode>"
+  [(set (match_operand:GPR 0 "gpc_reg_operand" "=r")
+	(if_then_else:GPR
+	 (match_operator 1 "scc_rev_comparison_operator"
+			 [(match_operand:CCUNS 4 "cc_reg_operand" "y")
+			  (const_int 0)])
+	 (match_operand:GPR 2 "gpc_reg_operand" "b")
+	 (match_operand:GPR 3 "gpc_reg_operand" "b")))]
+  "TARGET_ISEL<sel>"
+  "*
+{ return output_isel (operands); }"
+  [(set_attr "type" "isel")
+   (set_attr "length" "4")])
+
 (define_expand "movsfcc"
    [(set (match_operand:SF 0 "gpc_reg_operand" "")
 	 (if_then_else:SF (match_operand 1 "comparison_operator" "")