On 26 July 2016 at 17:41, Richard Biener <rguent...@suse.de> wrote:
> On Mon, 25 Jul 2016, Prathamesh Kulkarni wrote:
>
>> Hi,
>> The attached patch tries to fix PR71078.
>> I am not sure if I have got the converts right.
>> I put (convert? @0) and (convert1? (abs @1))
>> to match for cases when operands's types may
>> be different from outermost type like in pr71078-3.c
>
> Types of RDIV_EXPR have to be the same so as you have a
> match on @0 the converts need to be either both present
> or not present.
>
> + (if (FLOAT_TYPE_P (type)
>
> as you special-case several types below please use SCALAR_FLOAT_TYPE_P
> here.
>
> + && ! HONOR_NANS (type)
> + && ! HONOR_INFINITIES (type))
> + (switch
> + (if (type == float_type_node)
> + (BUILT_IN_COPYSIGNF { build_one_cst (type); } (convert @0)))
>
> please use if (types_match (type, float_type_node)) instead of
> pointer equality. I _think_ you can do better here by using
> IFN_COPYSIGN but possibly only so if the target supports it.
> Richard - this seems to be the first pattern in need of
> generating a builtin where no other was there to match the type
> to - any idea how we can safely use the internal function here?
> I see those do not have an expander that would fall back to
> expanding the regular builtin, correct?
>
> Please place the pattern next to
>
> /* Optimize -A / A to -1.0 if we don't care about
> NaNs or Infinities. */
> (simplify
> (rdiv:C @0 (negate @0))
> (if (FLOAT_TYPE_P (type)
> && ! HONOR_NANS (type)
> && ! HONOR_INFINITIES (type))
> { build_minus_one_cst (type); }))
>
> where it logically belongs.
Hi,
Is this version OK ?
Bootstrap + test in progress on x86_64-unknown-linux-gnu.
Thanks,
Prathamesh
>
> Thanks,
> Richard.
>
>> test-case (included in patch).
>> Bootstrap+test in progress on x86_64-unknown-linux-gnu.
>>
>> Thanks,
>> Prathamesh
>>
>
> --
> Richard Biener <rguent...@suse.de>
> SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB
> 21284 (AG Nuernberg)
2016-07-27 Prathamesh Kulkarni <prathamesh.kulka...@linaro.org>
PR middle-end/71078
* match.pd (x / abs(x) -> copysign(1.0, x)): New pattern.
testsuite/
* gcc.dg/tree-ssa/pr71078-1.c: New test-case.
* gcc.dg/tree-ssa/pr71078-2.c: Likewise.
* gcc.dg/tree-ssa/pr71078-3.c: Likewise.
diff --git a/gcc/match.pd b/gcc/match.pd
index 21bf617..2fd898a 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -195,6 +195,20 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
&& ! HONOR_INFINITIES (type))
{ build_minus_one_cst (type); }))
+/* PR71078: x / abs(x) -> copysign (1.0, x) */
+(simplify
+ (rdiv:C (convert? @0) (convert? (abs @0)))
+ (if (SCALAR_FLOAT_TYPE_P (type)
+ && ! HONOR_NANS (type)
+ && ! HONOR_INFINITIES (type))
+ (switch
+ (if (types_match (type, float_type_node))
+ (BUILT_IN_COPYSIGNF { build_one_cst (type); } (convert @0)))
+ (if (types_match (type, double_type_node))
+ (BUILT_IN_COPYSIGN { build_one_cst (type); } (convert @0)))
+ (if (types_match (type, long_double_type_node))
+ (BUILT_IN_COPYSIGNL { build_one_cst (type); } (convert @0))))))
+
/* In IEEE floating point, x/1 is not equivalent to x for snans. */
(simplify
(rdiv @0 real_onep)
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr71078-1.c
b/gcc/testsuite/gcc.dg/tree-ssa/pr71078-1.c
new file mode 100644
index 0000000..6204c14
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr71078-1.c
@@ -0,0 +1,29 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -ffast-math -fdump-tree-forwprop-details" } */
+
+#include <math.h>
+
+float f1(float x)
+{
+ float t1 = fabsf (x);
+ float t2 = x / t1;
+ return t2;
+}
+
+double f2(double x)
+{
+ double t1 = fabs (x);
+ double t2 = x / t1;
+ return t2;
+}
+
+long double f3 (long double x)
+{
+ long double t1 = fabsl (x);
+ long double t2 = x / t1;
+ return t2;
+}
+
+/* { dg-final { scan-tree-dump "__builtin_copysignf" "forwprop1" } } */
+/* { dg-final { scan-tree-dump "__builtin_copysign" "forwprop1" } } */
+/* { dg-final { scan-tree-dump "__builtin_copysignl" "forwprop1" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr71078-2.c
b/gcc/testsuite/gcc.dg/tree-ssa/pr71078-2.c
new file mode 100644
index 0000000..96485af
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr71078-2.c
@@ -0,0 +1,29 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -ffast-math -fdump-tree-forwprop-details" } */
+
+#include <math.h>
+
+float f1(float x)
+{
+ float t1 = fabsf (x);
+ float t2 = t1 / x;
+ return t2;
+}
+
+double f2(double x)
+{
+ double t1 = fabs (x);
+ double t2 = t1 / x;
+ return t2;
+}
+
+long double f3 (long double x)
+{
+ long double t1 = fabsl (x);
+ long double t2 = t1 / x;
+ return t2;
+}
+
+/* { dg-final { scan-tree-dump "__builtin_copysignf" "forwprop1" } } */
+/* { dg-final { scan-tree-dump "__builtin_copysign" "forwprop1" } } */
+/* { dg-final { scan-tree-dump "__builtin_copysignl" "forwprop1" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr71078-3.c
b/gcc/testsuite/gcc.dg/tree-ssa/pr71078-3.c
new file mode 100644
index 0000000..8780b6a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr71078-3.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -ffast-math -fdump-tree-forwprop-details" } */
+
+#include <math.h>
+double f(float f)
+{
+ double t1 = fabs(f);
+ double t2 = f / t1;
+ return t2;
+}
+
+/* { dg-final { scan-tree-dump "__builtin_copysign" "forwprop1" } } */
