pa.md (shadd): Create shadd insns, even if the result of the shift is needed without the addition.

0
        * pa.md (shadd): Create shadd insns, even if the result of the shift is
        needed without the addition.

From-SVN: r24700

gcc/config/pa/pa.md

@@ -3627,6 +3627,42 @@
   [(set_attr "type" "binary")
    (set_attr "length" "4")])
 
+;; This anonymous pattern and splitter wins because it reduces the latency
+;; of the shadd sequence without increasing the latency of the shift.
+;;
+;; We want to make sure and split up the operations for the scheduler since
+;; these instructions can (and should) schedule independently.
+;;
+;; It would be clearer if combine used the same operator for both expressions,
+;; it's somewhat confusing to have a mult in ine operation and an ashift
+;; in the other.
+(define_insn ""
+  [(set (match_operand:SI 0 "register_operand" "=r")
+	(plus:SI (mult:SI (match_operand:SI 2 "register_operand" "r")
+			  (match_operand:SI 3 "shadd_operand" ""))
+		 (match_operand:SI 1 "register_operand" "r")))
+   (set (match_operand:SI 4 "register_operand" "=r")
+	(ashift:SI (match_dup 2)
+		   (match_operand:SI 5 "const_int_operand" "i")))]
+  "INTVAL (operands[5]) == exact_log2 (INTVAL (operands[3]))"
+  "#"
+  [(set_attr "type" "binary")
+   (set_attr "length" "8")])
+
+(define_split
+  [(set (match_operand:SI 0 "register_operand" "=r")
+	(plus:SI (mult:SI (match_operand:SI 2 "register_operand" "r")
+			  (match_operand:SI 3 "shadd_operand" ""))
+		 (match_operand:SI 1 "register_operand" "r")))
+   (set (match_operand:SI 4 "register_operand" "=r")
+	(ashift:SI (match_dup 2)
+		   (match_operand:SI 5 "const_int_operand" "i")))]
+  "INTVAL (operands[5]) == exact_log2 (INTVAL (operands[3]))"
+  [(set (match_dup 4) (ashift:SI (match_dup 2) (match_dup 5)))
+   (set (match_dup 0) (plus:SI (mult:SI (match_dup 2) (match_dup 3))
+			       (match_dup 1)))]
+  "")
+
 ;; This variant of the above insn can occur if the first operand
 ;; is the frame pointer.  This is a kludge, but there doesn't
 ;; seem to be a way around it.  Only recognize it while reloading.