On Tue, Dec 2, 2014 at 6:05 AM, Uros Bizjak <ubiz...@gmail.com> wrote:
> On Tue, Dec 2, 2014 at 3:03 PM, H.J. Lu <hjl.to...@gmail.com> wrote:
>> On Tue, Dec 2, 2014 at 5:25 AM, Uros Bizjak <ubiz...@gmail.com> wrote:
>>> On Sat, Nov 29, 2014 at 3:00 PM, H.J. Lu <hjl.to...@gmail.com> wrote:
>>>> When searching for an usable algorithm with -minline-all-stringops,
>>>> decide_alg stops when it sees libcall even if there is a usable
>>>> algorithm. It goes into an infinite loop. This patch changes
>>>> decide_alg to stop searching only if there aren't any usable algorithms.
>>>> Testd on Linux/x86-64. OK for trunk.
>>>>
>>>>
>>>> H.J.
>>>> ----
>>>> gcc/
>>>>
>>>> 2014-11-29 H.J. Lu <hongjiu...@intel.com>
>>>>
>>>> PR target/64108
>>>> * config/i386/i386.c (decide_alg): Stop only if there aren't
>>>> any usable algorithms.
>>>>
>>>> gcc/testsuite/
>>>>
>>>> 2014-11-29 H.J. Lu <hongjiu...@intel.com>
>>>>
>>>> PR target/64108
>>>> * gcc.target/i386/memset-strategy-2.c: New test.
>>>
>>> OK with a change below. Please wait a couple of days before
>>> backporting the fix - the fix looks kind of obvious, but this part of
>>> the code is somehow complex and has biten us in the past.
>>
>> Will do.
>>
>>> Thanks,
>>> Uros.
>>>
>>>> diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
>>>> index 2493130..d789635 100644
>>>> --- a/gcc/config/i386/i386.c
>>>> +++ b/gcc/config/i386/i386.c
>>>> @@ -24464,7 +24464,9 @@ decide_alg (HOST_WIDE_INT count, HOST_WIDE_INT
>>>> expected_size,
>>>> *noalign = alg_noalign;
>>>> return alg;
>>>> }
>>>> - break;
>>>> + /* Stop only if there aren't any usable algorithms. */
>>>> + if (!any_alg_usable_p)
>>>> + break;
>>>
>>> Please use "else if ..." and remove unneded argument. IMO, the code
>>> speaks for itself.
>>
>> Which unneeded argument to remove? All arguments of decide_alg are
>> used.
>
> Eh, slip of the tongue. Unnedded *comment*, the one your patch is adding.
>
> Uros.
This is what I checked in. I will wait for a few days before backporting
it to 4.9.
Thanks.
--
H.J.
---
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 3eacc5a..c746d0f 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2014-12-02 H.J. Lu <hongjiu...@intel.com>
+
+ PR target/64108
+ * config/i386/i386.c (decide_alg): Stop only if there aren't
+ any usable algorithms.
+
2014-12-02 Tom de Vries <t...@codesourcery.com>
PR rtl-optimization/63718
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 3397167..211c9e6 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -24464,7 +24464,8 @@ decide_alg (HOST_WIDE_INT count, HOST_WIDE_INT
expected_size,
*noalign = alg_noalign;
return alg;
}
- break;
+ else if (!any_alg_usable_p)
+ break;
}
else if (alg_usable_p (candidate, memset))
{
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 00da0bd..5d66849 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2014-12-02 H.J. Lu <hongjiu...@intel.com>
+
+ PR target/64108
+ * gcc.target/i386/memset-strategy-2.c: New test.
+
2014-12-02 Richard Biener <rguent...@suse.de>
* gcc.dg/torture/20141202-1.c: New testcase.
diff --git a/gcc/testsuite/gcc.target/i386/memset-strategy-2.c
b/gcc/testsuite/gcc.target/i386/memset-strategy-2.c
new file mode 100644
index 0000000..aafa54d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/memset-strategy-2.c
@@ -0,0 +1,10 @@
+/* PR target/64108 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -march=atom -mmemset-strategy=libcall:-1:align
-minline-all-stringops" } */
+
+char a[2048];
+void t (void)
+{
+ __builtin_memset (a, 1, 2048);
+}
+
