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-rw-r--r--gcc/ChangeLog8
-rw-r--r--gcc/simplify-rtx.c36
-rw-r--r--gcc/testsuite/ChangeLog5
-rw-r--r--gcc/testsuite/gcc.target/i386/387-10.c20
4 files changed, 62 insertions, 7 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index dc310f6..97ec80cd 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2006-05-29 Roger Sayle <roger@eyesopen.com>
+
+ PR tree-optimization/24964
+ * simplify-rtx.c (simplify_binary_operation_1): Add function comment.
+ <MULT>: Minor clean-up. Don't convert x*-1.0 into -x if we honor
+ signaling NaNs. Optimize -x*-x as x*x for all float modes, and
+ abs(x)*abs(x) as x*x for scalar floating point modes.
+
2006-05-29 Sebastian Pop <pop@cri.ensmp.fr>
PR middle-end/27745
diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c
index 7199316..c51ca9e 100644
--- a/gcc/simplify-rtx.c
+++ b/gcc/simplify-rtx.c
@@ -1472,6 +1472,11 @@ simplify_binary_operation (enum rtx_code code, enum machine_mode mode,
return simplify_binary_operation_1 (code, mode, op0, op1, trueop0, trueop1);
}
+/* Subroutine of simplify_binary_operation. Simplify a binary operation
+ CODE with result mode MODE, operating on OP0 and OP1. If OP0 and/or
+ OP1 are constant pool references, TRUEOP0 and TRUEOP1 represent the
+ actual constants. */
+
static rtx
simplify_binary_operation_1 (enum rtx_code code, enum machine_mode mode,
rtx op0, rtx op1, rtx trueop0, rtx trueop1)
@@ -1907,12 +1912,12 @@ simplify_binary_operation_1 (enum rtx_code code, enum machine_mode mode,
return simplify_gen_binary (ASHIFT, mode, op0, GEN_INT (val));
/* Likewise for multipliers wider than a word. */
- else if (GET_CODE (trueop1) == CONST_DOUBLE
- && (GET_MODE (trueop1) == VOIDmode
- || GET_MODE_CLASS (GET_MODE (trueop1)) == MODE_INT)
- && GET_MODE (op0) == mode
- && CONST_DOUBLE_LOW (trueop1) == 0
- && (val = exact_log2 (CONST_DOUBLE_HIGH (trueop1))) >= 0)
+ if (GET_CODE (trueop1) == CONST_DOUBLE
+ && (GET_MODE (trueop1) == VOIDmode
+ || GET_MODE_CLASS (GET_MODE (trueop1)) == MODE_INT)
+ && GET_MODE (op0) == mode
+ && CONST_DOUBLE_LOW (trueop1) == 0
+ && (val = exact_log2 (CONST_DOUBLE_HIGH (trueop1))) >= 0)
return simplify_gen_binary (ASHIFT, mode, op0,
GEN_INT (val + HOST_BITS_PER_WIDE_INT));
@@ -1927,10 +1932,27 @@ simplify_binary_operation_1 (enum rtx_code code, enum machine_mode mode,
if (REAL_VALUES_EQUAL (d, dconst2))
return simplify_gen_binary (PLUS, mode, op0, copy_rtx (op0));
- if (REAL_VALUES_EQUAL (d, dconstm1))
+ if (!HONOR_SNANS (mode)
+ && REAL_VALUES_EQUAL (d, dconstm1))
return simplify_gen_unary (NEG, mode, op0, mode);
}
+ /* Optimize -x * -x as x * x. */
+ if (FLOAT_MODE_P (mode)
+ && GET_CODE (op0) == NEG
+ && GET_CODE (op1) == NEG
+ && rtx_equal_p (XEXP (op0, 0), XEXP (op1, 0))
+ && !side_effects_p (XEXP (op0, 0)))
+ return simplify_gen_binary (MULT, mode, XEXP (op0, 0), XEXP (op1, 0));
+
+ /* Likewise, optimize abs(x) * abs(x) as x * x. */
+ if (SCALAR_FLOAT_MODE_P (mode)
+ && GET_CODE (op0) == ABS
+ && GET_CODE (op1) == ABS
+ && rtx_equal_p (XEXP (op0, 0), XEXP (op1, 0))
+ && !side_effects_p (XEXP (op0, 0)))
+ return simplify_gen_binary (MULT, mode, XEXP (op0, 0), XEXP (op1, 0));
+
/* Reassociate multiplication, but for floating point MULTs
only when the user specifies unsafe math optimizations. */
if (! FLOAT_MODE_P (mode)
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 96c5729..8778352 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2006-05-29 Roger Sayle <roger@eyesopen.com>
+
+ PR tree-optimization/24964
+ * gcc.target/i386/387-10.c: New test case.
+
2006-05-28 Thomas Koenig <Thomas.Koenig@online.de>
* intrinsics/string_intrinsics.c (compare_string):
diff --git a/gcc/testsuite/gcc.target/i386/387-10.c b/gcc/testsuite/gcc.target/i386/387-10.c
new file mode 100644
index 0000000..150515b
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/387-10.c
@@ -0,0 +1,20 @@
+/* PR tree-optimization/24964 */
+/* { dg-do compile { target i?86-*-* x86_64-*-* } } */
+/* { dg-options "-O2 -mfpmath=387" } */
+
+double fabs(double x);
+
+double test1(double x)
+{
+ double t = fabs(x);
+ return t*t;
+}
+
+double test2(double x)
+{
+ double t = -x;
+ return t*t;
+}
+
+/* { dg-final { scan-assembler-not "fchs" } } */
+/* { dg-final { scan-assembler-not "fabs" } } */