builtins.c (fold_builtin_hypot): Rearrange recursive transformation before others, and also do ABS_EXPR.

	* builtins.c (fold_builtin_hypot): Rearrange recursive
	transformation before others, and also do ABS_EXPR.  When
	necessary, check flag_unsafe_math_optimizations.  When necessary,
	add fabs.

testsuite:
	* gcc.dg/builtins-20.c: Add more hypot tests.

From-SVN: r118160

4 files changed, 107 insertions, 19 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 1a5c2cf..c4f0bcd 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2006-10-29  Kaveh R. Ghazi  <ghazi@caip.rutgers.edu>
+
+	* builtins.c (fold_builtin_hypot): Rearrange recursive
+	transformation before others, and also do ABS_EXPR.  When
+	necessary, check flag_unsafe_math_optimizations.  When necessary,
+	add fabs.
+
 2006-10-29  Roger Sayle  <roger@eyesopen.com>
 
 	* fold-const.c (fold_comparison): Fold ~X op ~Y as Y op X.
diff --git a/gcc/builtins.c b/gcc/builtins.c
index 5375c5c..3af86cc 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -7677,35 +7677,40 @@ fold_builtin_hypot (tree fndecl, tree arglist, tree type)
   if ((res = do_mpfr_arg2 (arg0, arg1, type, mpfr_hypot)))
     return res;
   
+  /* If either argument to hypot has a negate or abs, strip that off.
+     E.g. hypot(-x,fabs(y)) -> hypot(x,y).  */
+  if (TREE_CODE (arg0) == NEGATE_EXPR || TREE_CODE (arg1) == NEGATE_EXPR
+      || TREE_CODE (arg0) == ABS_EXPR || TREE_CODE (arg1) == ABS_EXPR)
+    {
+      tree narg0 = (TREE_CODE (arg0) == NEGATE_EXPR
+		    || TREE_CODE (arg0) == ABS_EXPR)
+	? TREE_OPERAND (arg0, 0) : arg0;
+      tree narg1 = (TREE_CODE (arg1) == NEGATE_EXPR
+		    || TREE_CODE (arg1) == ABS_EXPR)
+	? TREE_OPERAND (arg1, 0) : arg1;
+      tree narglist = tree_cons (NULL_TREE, narg0,
+				 build_tree_list (NULL_TREE, narg1));
+      return build_function_call_expr (fndecl, narglist);
+    }
+  
   /* If either argument is zero, hypot is fabs of the other.  */
   if (real_zerop (arg0))
     return fold_build1 (ABS_EXPR, type, arg1);
   else if (real_zerop (arg1))
     return fold_build1 (ABS_EXPR, type, arg0);
       
-  /* hypot(x,x) -> x*sqrt(2).  */
-  if (operand_equal_p (arg0, arg1, OEP_PURE_SAME))
+  /* hypot(x,x) -> fabs(x)*sqrt(2).  */
+  if (flag_unsafe_math_optimizations
+      && operand_equal_p (arg0, arg1, OEP_PURE_SAME))
     {
       REAL_VALUE_TYPE sqrt2;
 
       real_sqrt (&sqrt2, TYPE_MODE (type), &dconst2);
-      return fold_build2 (MULT_EXPR, type, arg0,
+      return fold_build2 (MULT_EXPR, type,
+			  fold_build1 (ABS_EXPR, type, arg0),
 			  build_real (type, sqrt2));
     }
 
-  /* Transform hypot(-x,y) or hypot(x,-y) or hypot(-x,-y) into
-     hypot(x,y).  */
-  if (TREE_CODE (arg0) == NEGATE_EXPR || TREE_CODE (arg1) == NEGATE_EXPR)
-    {
-      tree narg0 = (TREE_CODE (arg0) == NEGATE_EXPR)
-	? TREE_OPERAND (arg0, 0) : arg0;
-      tree narg1 = (TREE_CODE (arg1) == NEGATE_EXPR)
-	? TREE_OPERAND (arg1, 0) : arg1;
-      tree narglist = tree_cons (NULL_TREE, narg0,
-				 build_tree_list (NULL_TREE, narg1));
-      return build_function_call_expr (fndecl, narglist);
-    }
-  
   return NULL_TREE;
 }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index bec0930..23cc4a0 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2006-10-29  Kaveh R. Ghazi  <ghazi@caip.rutgers.edu>
+
+	* gcc.dg/builtins-20.c: Add more hypot tests.
+
 2006-10-29  Roger Sayle  <roger@eyesopen.com>
 
 	* gcc.dg/fold-compare-1.c: New test case.
diff --git a/gcc/testsuite/gcc.dg/builtins-20.c b/gcc/testsuite/gcc.dg/builtins-20.c
index 1c8bb9b..d4161d1 100644
--- a/gcc/testsuite/gcc.dg/builtins-20.c
+++ b/gcc/testsuite/gcc.dg/builtins-20.c
@@ -16,14 +16,17 @@ extern double cos (double);
 extern double sin (double);
 extern double tan (double);
 extern double hypot (double, double);
+extern double pure (double) __attribute__ ((__pure__));
 extern float cosf (float);
 extern float sinf (float);
 extern float tanf (float);
 extern float hypotf (float, float);
+extern float puref (float) __attribute__ ((__pure__));
 extern long double cosl (long double);
 extern long double sinl (long double);
 extern long double tanl (long double);
 extern long double hypotl (long double, long double);
+extern long double purel (long double) __attribute__ ((__pure__));
 
 extern void link_error(void);
 
@@ -65,7 +68,7 @@ void test2(double x, double y)
   if (hypot (0, x) != __builtin_fabs(x))
     link_error ();
 
-  if (hypot (x, x) != x * __builtin_sqrt(2))
+  if (hypot (x, x) != __builtin_fabs(x) * __builtin_sqrt(2))
     link_error ();
 
   if (hypot (-x, y) != hypot (x, y))
@@ -76,6 +79,29 @@ void test2(double x, double y)
 
   if (hypot (-x, -y) != hypot (x, y))
     link_error ();
+
+  if (hypot (__builtin_fabs(x), y) != hypot (x, y))
+    link_error ();
+
+  if (hypot (x, __builtin_fabs(y)) != hypot (x, y))
+    link_error ();
+
+  if (hypot (__builtin_fabs(x), __builtin_fabs(y)) != hypot (x, y))
+    link_error ();
+
+  if (hypot (-__builtin_fabs(-x),
+	     -__builtin_fabs(__builtin_fabs(__builtin_fabs(-y))))
+      != hypot (x, y))
+    link_error ();
+
+  if (hypot (-x, 0) != __builtin_fabs(x))
+    link_error ();
+
+  if (hypot (-x, x) != __builtin_fabs(x) * __builtin_sqrt(2))
+    link_error ();
+
+  if (hypot (pure(x), -pure(x)) != __builtin_fabs(pure(x)) * __builtin_sqrt(2))
+    link_error ();
 }
 
 void test1f(float x)
@@ -118,7 +144,7 @@ void test2f(float x, float y)
   if (hypotf (0, x) != __builtin_fabsf(x))
     link_error ();
 
-  if (hypotf (x, x) != x * __builtin_sqrtf(2))
+  if (hypotf (x, x) != __builtin_fabsf(x) * __builtin_sqrtf(2))
     link_error ();
 
   if (hypotf (-x, y) != hypotf (x, y))
@@ -129,6 +155,29 @@ void test2f(float x, float y)
 
   if (hypotf (-x, -y) != hypotf (x, y))
     link_error ();
+
+  if (hypotf (__builtin_fabsf(x), y) != hypotf (x, y))
+    link_error ();
+
+  if (hypotf (x, __builtin_fabsf(y)) != hypotf (x, y))
+    link_error ();
+
+  if (hypotf (__builtin_fabsf(x), __builtin_fabsf(y)) != hypotf (x, y))
+    link_error ();
+
+  if (hypotf (-__builtin_fabsf(-x),
+	      -__builtin_fabsf(__builtin_fabsf(__builtin_fabsf(-y))))
+      != hypotf (x, y))
+    link_error ();
+
+  if (hypotf (-x, 0) != __builtin_fabsf(x))
+    link_error ();
+
+  if (hypotf (-x, x) != __builtin_fabsf(x) * __builtin_sqrtf(2))
+    link_error ();
+
+  if (hypotf (puref(x), -puref(x)) != __builtin_fabsf(puref(x)) * __builtin_sqrtf(2))
+    link_error ();
 }
 
 
@@ -172,7 +221,7 @@ void test2l(long double x, long double y)
   if (hypotl (0, x) != __builtin_fabsl(x))
     link_error ();
 
-  if (hypotl (x, x) != x * __builtin_sqrtl(2))
+  if (hypotl (x, x) != __builtin_fabsl(x) * __builtin_sqrtl(2))
     link_error ();
 
   if (hypotl (-x, y) != hypotl (x, y))
@@ -183,6 +232,29 @@ void test2l(long double x, long double y)
 
   if (hypotl (-x, -y) != hypotl (x, y))
     link_error ();
+
+  if (hypotl (__builtin_fabsl(x), y) != hypotl (x, y))
+    link_error ();
+
+  if (hypotl (x, __builtin_fabsl(y)) != hypotl (x, y))
+    link_error ();
+
+  if (hypotl (__builtin_fabsl(x), __builtin_fabsl(y)) != hypotl (x, y))
+    link_error ();
+
+  if (hypotl (-__builtin_fabsl(-x),
+	      -__builtin_fabsl(__builtin_fabsl(__builtin_fabsl(-y))))
+      != hypotl (x, y))
+    link_error ();
+
+  if (hypotl (-x, 0) != __builtin_fabsl(x))
+    link_error ();
+
+  if (hypotl (-x, x) != __builtin_fabsl(x) * __builtin_sqrtl(2))
+    link_error ();
+
+  if (hypotl (purel(x), -purel(x)) != __builtin_fabsl(purel(x)) * __builtin_sqrtl(2))
+    link_error ();
 }
 
 int main()