[PATCH MIDDLE-END]: more builtin cproj optimizations

[Kaveh R. GHAZI]

Here are a few more optimizations for builtin cproj, namely:

1.  If the real part is infinity and the imaginary part is known to be
unsigned, then we can return INF + 0i.

2.  If the imaginary part is infinity, then we can determine the
result regardless of what the real part is.

This patch depends on a previous one posted here:
http://gcc.gnu.org/ml/gcc-patches/2010-04/msg00490.html

Tested on x86_64-unknown-linux-gnu, no regressions.  Okay for mainline?

		Thanks,
		--Kaveh


2010-04-10  Kaveh R. Ghazi  <ghazi@caip.rutgers.edu>

	* builtins.c (fold_builtin_cproj): Fold more cases.

testsuite:
	* gcc.dg/torture/builtin-cproj-1.c: Test more cases.

diff -rup orig/egcc-SVN20100409/gcc/builtins.c egcc-SVN20100409/gcc/builtins.c
--- orig/egcc-SVN20100409/gcc/builtins.c	2010-04-09 21:17:23.000000000 +0200
+++ egcc-SVN20100409/gcc/builtins.c	2010-04-09 22:18:37.000000000 +0200
@@ -6995,6 +6995,33 @@ fold_builtin_cproj (location_t loc, tree
       else
 	return arg;
     }
+  else if (TREE_CODE (arg) == COMPLEX_EXPR)
+    {
+      tree real = TREE_OPERAND (arg, 0);
+      tree imag = TREE_OPERAND (arg, 1);
+
+      STRIP_NOPS (real);
+      STRIP_NOPS (imag);
+
+      /* If the real part is inf and the imag part is known to be
+	 nonnegative, return (inf + 0i).  Remember side-effects are
+	 possible in the imag part.  */
+      if (TREE_CODE (real) == REAL_CST
+	  && real_isinf (TREE_REAL_CST_PTR (real))
+	  && tree_expr_nonnegative_p (imag))
+	return omit_one_operand_loc (loc, type,
+				     build_complex_cproj (type, false),
+				     arg);
+
+      /* If the imag part is inf, return (inf+I*copysign(0,imag)).
+	 Remember side-effects are possible in the real part.  */
+      if (TREE_CODE (imag) == REAL_CST
+	  && real_isinf (TREE_REAL_CST_PTR (imag)))
+	return
+	  omit_one_operand_loc (loc, type,
+				build_complex_cproj (type, TREE_REAL_CST_PTR
+						     (imag)->sign), arg);
+    }

   return NULL_TREE;
 }
diff -rup orig/egcc-SVN20100409/gcc/testsuite/gcc.dg/torture/builtin-cproj-1.c egcc-SVN20100409/gcc/testsuite/gcc.dg/torture/builtin-cproj-1.c
--- orig/egcc-SVN20100409/gcc/testsuite/gcc.dg/torture/builtin-cproj-1.c	2010-04-09 21:17:23.000000000 +0200
+++ egcc-SVN20100409/gcc/testsuite/gcc.dg/torture/builtin-cproj-1.c	2010-04-10 18:02:19.000000000 +0200
@@ -44,7 +44,80 @@ extern void link_error(int);
     link_error(__LINE__); \
 } while (0)

-void foo (void)
+/* Test that cproj(X + I*INF) -> (ZERO + INF), where ZERO is +-0i.
+   NEG is either blank or a minus sign when ZERO is negative.  */
+#define TEST_IMAG_INF(NEG,ZERO) do { \
+  if (CPROJF(f+I*NEG INF) != ZERO+INF \
+      || CKSGN_I (CPROJF(f+I*NEG INF), ZERO+INF)) \
+    link_error(__LINE__); \
+  if (CPROJ(d+I*NEG INF) != ZERO+INF \
+      || CKSGN_I (CPROJ(d+I*NEG INF), ZERO+INF)) \
+    link_error(__LINE__); \
+  if (CPROJL(ld+I*NEG INF) != ZERO+INF \
+      || CKSGN_I (CPROJL(ld+I*NEG INF), ZERO+INF)) \
+    link_error(__LINE__); \
+} while (0)
+
+/* Like TEST_IMAG_INF, but check that side effects are honored.  */
+#define TEST_IMAG_INF_SIDE_EFFECT(NEG,ZERO) do { \
+  int side = 4; \
+  if (CPROJF(++side+I*NEG INF) != ZERO+INF \
+      || CKSGN_I (CPROJF(++side+I*NEG INF), ZERO+INF)) \
+    link_error(__LINE__); \
+  if (CPROJ(++side+I*NEG INF) != ZERO+INF \
+      || CKSGN_I (CPROJ(++side+I*NEG INF), ZERO+INF)) \
+    link_error(__LINE__); \
+  if (CPROJL(++side+I*NEG INF) != ZERO+INF \
+      || CKSGN_I (CPROJL(++side+I*NEG INF), ZERO+INF)) \
+    link_error(__LINE__); \
+  if (side != 10) \
+    link_error(__LINE__); \
+} while (0)
+
+/* Test that cproj(INF, POSITIVE) -> INF+0i.  NEG is either blank or a
+   minus sign to test negative INF.  */
+#define TEST_REAL_INF(NEG) do { \
+  __real cf = NEG INF; \
+  __imag cf = (x ? 4 : 5); \
+  if (CPROJF(cf) != INF \
+      || CKSGN_I (CPROJF(cf), INF)) \
+    link_error(__LINE__); \
+  __real cd = NEG INF; \
+  __imag cd = (x ? 4 : 5); \
+  if (CPROJ(cd) != INF \
+      || CKSGN_I (CPROJ(cd), INF)) \
+    link_error(__LINE__); \
+  __real cld = NEG INF; \
+  __imag cld = (x ? 4 : 5); \
+  if (CPROJL(cld) != INF \
+      || CKSGN_I (CPROJL(cld), INF)) \
+    link_error(__LINE__); \
+} while (0)
+
+/* Like TEST_REAL_INF, but check that side effects are honored.  */
+#define TEST_REAL_INF_SIDE_EFFECT(NEG) do { \
+  int side = -9; \
+  __real cf = NEG INF; \
+  __imag cf = (x ? 4 : 5); \
+  if (CPROJF((++side,cf)) != INF \
+      || CKSGN_I (CPROJF((++side,cf)), INF)) \
+    link_error(__LINE__); \
+  __real cd = NEG INF; \
+  __imag cd = (x ? 4 : 5); \
+  if (CPROJ((++side,cd)) != INF \
+      || CKSGN_I (CPROJ((++side,cd)), INF)) \
+    link_error(__LINE__); \
+  __real cld = NEG INF; \
+  __imag cld = (x ? 4 : 5); \
+  if (CPROJL((++side,cld)) != INF \
+      || CKSGN_I (CPROJL((++side,cld)), INF)) \
+    link_error(__LINE__); \
+  if (side != -3) \
+    link_error(__LINE__); \
+} while (0)
+
+void foo (_Complex long double cld, _Complex double cd, _Complex float cf,
+	  long double ld, double d, float f, int x)
 {
   TEST_CST_INF (INF+0I, 0);
   TEST_CST_INF (INF-0I, -0.FI);
@@ -79,6 +152,20 @@ void foo (void)
   TEST_CST (-22+3I);
   TEST_CST (-22-3I);

+  TEST_IMAG_INF (,0.FI);
+  TEST_IMAG_INF (-,-0.FI);
+
+#ifdef __OPTIMIZE__
+  TEST_REAL_INF( );
+  TEST_REAL_INF(-);
+
+  TEST_IMAG_INF_SIDE_EFFECT (,0.FI);
+  TEST_IMAG_INF_SIDE_EFFECT (-,-0.FI);
+
+  TEST_REAL_INF_SIDE_EFFECT( );
+  TEST_REAL_INF_SIDE_EFFECT(-);
+#endif
+
   return;
 }