mips.md: New reciprocal square root patterns that match sqrt(1.0/x) in addition to the...

	* config/mips/mips.md: New reciprocal square root patterns that
	match sqrt(1.0/x) in addition to the existing 1.0/sqrt(x) insns.

	* gcc.dg/mips-rsqrt-1.c: New test case.
	* gcc.dg/mips-rsqrt-2.c: New test case.
	* gcc.dg/mips-rsqrt-3.c: New test case.

From-SVN: r85759

gcc/ChangeLog

+2004-08-10  Roger Sayle  <roger@eyesopen.com>
+
+	* config/mips/mips.md: New reciprocal square root patterns that
+	match sqrt(1.0/x) in addition to the existing 1.0/sqrt(x) insns.
+
 2004-08-10  Paul Brook  <paul@codesourcery.com>
 
 	* config/arm/arm-protos.h (arm_set_return_address,

gcc/config/mips/mips.md

@@ -2203,6 +2203,46 @@
         (if_then_else (ne (symbol_ref "TARGET_FIX_SB1") (const_int 0))
                       (const_int 8)
                       (const_int 4)))])
+
+;; This pattern works around the early SB-1 rev2 core "F1" erratum (see
+;; "divdf3" comment for details).
+(define_insn ""
+  [(set (match_operand:DF 0 "register_operand" "=f")
+	(sqrt:DF (div:DF (match_operand:DF 1 "const_float_1_operand" "")
+			 (match_operand:DF 2 "register_operand" "f"))))]
+  "ISA_HAS_FP4 && TARGET_HARD_FLOAT && TARGET_DOUBLE_FLOAT && flag_unsafe_math_optimizations"
+{
+  if (TARGET_FIX_SB1)
+    return "rsqrt.d\t%0,%2\;mov.d\t%0,%0";
+  else
+    return "rsqrt.d\t%0,%2";
+}
+  [(set_attr "type"	"frsqrt")
+   (set_attr "mode"	"DF")
+   (set (attr "length")
+        (if_then_else (ne (symbol_ref "TARGET_FIX_SB1") (const_int 0))
+                      (const_int 8)
+                      (const_int 4)))])
+
+;; This pattern works around the early SB-1 rev2 core "F1" erratum (see
+;; "divdf3" comment for details).
+(define_insn ""
+  [(set (match_operand:SF 0 "register_operand" "=f")
+	(sqrt:SF (div:SF (match_operand:SF 1 "const_float_1_operand" "")
+			 (match_operand:SF 2 "register_operand" "f"))))]
+  "ISA_HAS_FP4 && TARGET_HARD_FLOAT && flag_unsafe_math_optimizations"
+{
+  if (TARGET_FIX_SB1)
+    return "rsqrt.s\t%0,%2\;mov.s\t%0,%0";
+  else
+    return "rsqrt.s\t%0,%2";
+}
+  [(set_attr "type"	"frsqrt")
+   (set_attr "mode"	"SF")
+   (set (attr "length")
+        (if_then_else (ne (symbol_ref "TARGET_FIX_SB1") (const_int 0))
+                      (const_int 8)
+                      (const_int 4)))])
 
 ;;
 ;;  ....................

gcc/testsuite/ChangeLog

+2004-08-10  Roger Sayle  <roger@eyesopen.com>
+
+	* gcc.dg/mips-rsqrt-1.c: New test case.
+	* gcc.dg/mips-rsqrt-2.c: New test case.
+	* gcc.dg/mips-rsqrt-3.c: New test case.
+
 2004-08-10  Paul Brook  <paul@codesourcery.com>
 
 	* gfortran.dg/der_io_1.f90: New test.

gcc/testsuite/gcc.dg/mips-rsqrt-1.c

+/* { dg-do compile { target "mips*-*-*" } } */
+/* { dg-options "-O2 -ffast-math -mips4" } */
+/* { dg-final { scan-assembler "rsqrt.d" } } */
+/* { dg-final { scan-assembler "rsqrt.s" } } */
+
+extern double sqrt(double);
+extern float sqrtf(float);
+
+double foo(double x)
+{
+  return 1.0/sqrt(x);
+}
+
+float bar(float x)
+{
+  return 1.0f/sqrtf(x);
+}
+

gcc/testsuite/gcc.dg/mips-rsqrt-2.c

+/* { dg-do compile { target "mips*-*-*" } } */
+/* { dg-options "-O2 -ffast-math -mips4" } */
+/* { dg-final { scan-assembler "rsqrt.d" } } */
+/* { dg-final { scan-assembler "rsqrt.s" } } */
+
+extern double sqrt(double);
+extern float sqrtf(float);
+
+double foo(double x)
+{
+  return sqrt(1.0/x);
+}
+
+float bar(float x)
+{
+  return sqrtf(1.0f/x);
+}
+

gcc/testsuite/gcc.dg/mips-rsqrt-3.c

+/* { dg-do compile { target "mips*-*-*" } } */
+/* { dg-options "-O2 -mips4" } */
+/* { dg-final { scan-assembler-not "rsqrt.d" } } */
+/* { dg-final { scan-assembler-not "rsqrt.s" } } */
+
+extern double sqrt(double);
+extern float sqrtf(float);
+
+double foo(double x)
+{
+  return 1.0/sqrt(x);
+}
+
+double bar(double x)
+{
+  return sqrt(1.0/x);
+}
+
+float foof(float x)
+{
+  return 1.0f/sqrtf(x);
+}
+
+float barf(float x)
+{
+  return sqrtf(1.0f/x);
+}
+