Re: [PATCH] combine: Tweak change_zero_ext

[Kyrill Tkachov]

On 30/11/16 10:02, Bin.Cheng wrote:

On Tue, Nov 29, 2016 at 9:14 PM, Christophe Lyon
 wrote:

On 29 November 2016 at 20:38, Uros Bizjak  wrote:

2016-11-26  Segher Boessenkool  

* combine.c (change_zero_ext): Also handle extends from a subreg
to a mode bigger than that of the operand of the subreg.

This patch introduced:

FAIL: gcc.target/i386/pr44578.c (internal compiler error)

on i686 (or x86_64 32bit multi-lib).

./cc1 -O2 -mtune=athlon64 -m32 -quiet pr44578.c
pr44578.c: In function ‘test’:
pr44578.c:18:1: internal compiler error: in gen_rtx_SUBREG, at emit-rtl.c:908
  }
  ^
0x81493b gen_rtx_SUBREG(machine_mode, rtx_def*, int)
 /home/uros/gcc-svn/trunk/gcc/emit-rtl.c:908
0x122609f change_zero_ext
 /home/uros/gcc-svn/trunk/gcc/combine.c:11260
0x1226207 recog_for_combine
 /home/uros/gcc-svn/trunk/gcc/combine.c:11346
0x1236db3 try_combine
 /home/uros/gcc-svn/trunk/gcc/combine.c:3501
0x123a3e0 combine_instructions
 /home/uros/gcc-svn/trunk/gcc/combine.c:1265
0x123a3e0 rest_of_handle_combine
 /home/uros/gcc-svn/trunk/gcc/combine.c:14581
0x123a3e0 execute
 /home/uros/gcc-svn/trunk/gcc/combine.c:14626

Uros.

Hi,

I'm seeing a similar error on aarch64:
FAIL: gcc.target/aarch64/advsimd-intrinsics/vduph_lane.c   -O1
(internal compiler error)
with the same backtrace.

Hi,
I also saw the same failure for below tests on aarch64.

/tmp/.../src/gcc/gcc/testsuite/gcc.target/aarch64/advsimd-intrinsics/vget_lane.c:
In function 'exec_vget_lane':
/tmp/.../src/gcc/gcc/testsuite/gcc.target/aarch64/advsimd-intrinsics/vget_lane.c:136:1:
internal compiler error: in gen_rtx_SUBREG, at emit-rtl.c:908
0x7d9cd1 gen_rtx_SUBREG(machine_mode, rtx_def*, int)
 /tmp/.../src/gcc/gcc/emit-rtl.c:908
0x7d9d25 gen_lowpart_SUBREG(machine_mode, rtx_def*)
 /tmp/.../src/gcc/gcc/emit-rtl.c:924
0x1112562 change_zero_ext
 /tmp/.../src/gcc/gcc/combine.c:11260
0x1112b47 recog_for_combine
 /tmp/.../src/gcc/gcc/combine.c:11346


This is PR 78590 and Segher fixed it today.
Kyrill


Thanks,
bin

Christophe

Re: [PATCH] combine: Tweak change_zero_ext

[Bin.Cheng]

On Tue, Nov 29, 2016 at 9:14 PM, Christophe Lyon
 wrote:
> On 29 November 2016 at 20:38, Uros Bizjak  wrote:
>>> 2016-11-26  Segher Boessenkool  
>>>
>>> * combine.c (change_zero_ext): Also handle extends from a subreg
>>> to a mode bigger than that of the operand of the subreg.
>>
>> This patch introduced:
>>
>> FAIL: gcc.target/i386/pr44578.c (internal compiler error)
>>
>> on i686 (or x86_64 32bit multi-lib).
>>
>> ./cc1 -O2 -mtune=athlon64 -m32 -quiet pr44578.c
>> pr44578.c: In function ‘test’:
>> pr44578.c:18:1: internal compiler error: in gen_rtx_SUBREG, at emit-rtl.c:908
>>  }
>>  ^
>> 0x81493b gen_rtx_SUBREG(machine_mode, rtx_def*, int)
>> /home/uros/gcc-svn/trunk/gcc/emit-rtl.c:908
>> 0x122609f change_zero_ext
>> /home/uros/gcc-svn/trunk/gcc/combine.c:11260
>> 0x1226207 recog_for_combine
>> /home/uros/gcc-svn/trunk/gcc/combine.c:11346
>> 0x1236db3 try_combine
>> /home/uros/gcc-svn/trunk/gcc/combine.c:3501
>> 0x123a3e0 combine_instructions
>> /home/uros/gcc-svn/trunk/gcc/combine.c:1265
>> 0x123a3e0 rest_of_handle_combine
>> /home/uros/gcc-svn/trunk/gcc/combine.c:14581
>> 0x123a3e0 execute
>> /home/uros/gcc-svn/trunk/gcc/combine.c:14626
>>
>> Uros.
>
> Hi,
>
> I'm seeing a similar error on aarch64:
> FAIL: gcc.target/aarch64/advsimd-intrinsics/vduph_lane.c   -O1
> (internal compiler error)
> with the same backtrace.
Hi,
I also saw the same failure for below tests on aarch64.

/tmp/.../src/gcc/gcc/testsuite/gcc.target/aarch64/advsimd-intrinsics/vget_lane.c:
In function 'exec_vget_lane':
/tmp/.../src/gcc/gcc/testsuite/gcc.target/aarch64/advsimd-intrinsics/vget_lane.c:136:1:
internal compiler error: in gen_rtx_SUBREG, at emit-rtl.c:908
0x7d9cd1 gen_rtx_SUBREG(machine_mode, rtx_def*, int)
/tmp/.../src/gcc/gcc/emit-rtl.c:908
0x7d9d25 gen_lowpart_SUBREG(machine_mode, rtx_def*)
/tmp/.../src/gcc/gcc/emit-rtl.c:924
0x1112562 change_zero_ext
/tmp/.../src/gcc/gcc/combine.c:11260
0x1112b47 recog_for_combine
/tmp/.../src/gcc/gcc/combine.c:11346

Thanks,
bin
>
> Christophe

Re: [PATCH] combine: Tweak change_zero_ext

[Christophe Lyon]

On 29 November 2016 at 20:38, Uros Bizjak  wrote:
>> 2016-11-26  Segher Boessenkool  
>>
>> * combine.c (change_zero_ext): Also handle extends from a subreg
>> to a mode bigger than that of the operand of the subreg.
>
> This patch introduced:
>
> FAIL: gcc.target/i386/pr44578.c (internal compiler error)
>
> on i686 (or x86_64 32bit multi-lib).
>
> ./cc1 -O2 -mtune=athlon64 -m32 -quiet pr44578.c
> pr44578.c: In function ‘test’:
> pr44578.c:18:1: internal compiler error: in gen_rtx_SUBREG, at emit-rtl.c:908
>  }
>  ^
> 0x81493b gen_rtx_SUBREG(machine_mode, rtx_def*, int)
> /home/uros/gcc-svn/trunk/gcc/emit-rtl.c:908
> 0x122609f change_zero_ext
> /home/uros/gcc-svn/trunk/gcc/combine.c:11260
> 0x1226207 recog_for_combine
> /home/uros/gcc-svn/trunk/gcc/combine.c:11346
> 0x1236db3 try_combine
> /home/uros/gcc-svn/trunk/gcc/combine.c:3501
> 0x123a3e0 combine_instructions
> /home/uros/gcc-svn/trunk/gcc/combine.c:1265
> 0x123a3e0 rest_of_handle_combine
> /home/uros/gcc-svn/trunk/gcc/combine.c:14581
> 0x123a3e0 execute
> /home/uros/gcc-svn/trunk/gcc/combine.c:14626
>
> Uros.

Hi,

I'm seeing a similar error on aarch64:
FAIL: gcc.target/aarch64/advsimd-intrinsics/vduph_lane.c   -O1
(internal compiler error)
with the same backtrace.

Christophe

Re: [PATCH] combine: Tweak change_zero_ext

[Uros Bizjak]

> 2016-11-26  Segher Boessenkool  
>
> * combine.c (change_zero_ext): Also handle extends from a subreg
> to a mode bigger than that of the operand of the subreg.

This patch introduced:

FAIL: gcc.target/i386/pr44578.c (internal compiler error)

on i686 (or x86_64 32bit multi-lib).

./cc1 -O2 -mtune=athlon64 -m32 -quiet pr44578.c
pr44578.c: In function ‘test’:
pr44578.c:18:1: internal compiler error: in gen_rtx_SUBREG, at emit-rtl.c:908
 }
 ^
0x81493b gen_rtx_SUBREG(machine_mode, rtx_def*, int)
/home/uros/gcc-svn/trunk/gcc/emit-rtl.c:908
0x122609f change_zero_ext
/home/uros/gcc-svn/trunk/gcc/combine.c:11260
0x1226207 recog_for_combine
/home/uros/gcc-svn/trunk/gcc/combine.c:11346
0x1236db3 try_combine
/home/uros/gcc-svn/trunk/gcc/combine.c:3501
0x123a3e0 combine_instructions
/home/uros/gcc-svn/trunk/gcc/combine.c:1265
0x123a3e0 rest_of_handle_combine
/home/uros/gcc-svn/trunk/gcc/combine.c:14581
0x123a3e0 execute
/home/uros/gcc-svn/trunk/gcc/combine.c:14626

Uros.

[PATCH] combine: Tweak change_zero_ext

[Segher Boessenkool]

change_zero_ext handles (zero_extend:M1 (subreg:M2 (reg:M1) ...))
already; this patch extends it to also deal with any
(zero_extend:M1 (subreg:M2 (reg:M3) ...)) where the subreg is not
paradoxical.

Tested on powerpc64-linux.  This is needed for some of the rlwimi
testcases to be optimised properly.


Segher


2016-11-26  Segher Boessenkool  

* combine.c (change_zero_ext): Also handle extends from a subreg
to a mode bigger than that of the operand of the subreg.

---
 gcc/combine.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/gcc/combine.c b/gcc/combine.c
index 4b3496b..2c3bcf1 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -11275,11 +11275,13 @@ change_zero_ext (rtx pat)
   else if (GET_CODE (x) == ZERO_EXTEND
   && SCALAR_INT_MODE_P (mode)
   && GET_CODE (XEXP (x, 0)) == SUBREG
-  && GET_MODE (SUBREG_REG (XEXP (x, 0))) == mode
+  && !paradoxical_subreg_p (XEXP (x, 0))
   && subreg_lowpart_p (XEXP (x, 0)))
{
  size = GET_MODE_PRECISION (GET_MODE (XEXP (x, 0)));
  x = SUBREG_REG (XEXP (x, 0));
+ if (GET_MODE (x) != mode)
+   x = gen_lowpart_SUBREG (mode, x);
}
   else if (GET_CODE (x) == ZERO_EXTEND
   && SCALAR_INT_MODE_P (mode)
-- 
1.9.3