gcc

ICE in reload_cse_simplify_operands, at postreload.c:402 with neon optimized code

Bug #744754 reported by Luke Kim on 2011-03-29

This bug affects 3 people

Affects		Status	Importance	Assigned to	Milestone
	Linaro GCC	Fix Released	Medium	Ramana Radhakrishnan	Linaro GCC 4.6-2011.07
	gcc	Confirmed	Medium	gcc-bugzilla #48325

Bug Description

While building neon optimized code

$ cat insn-unsat-constr.c
#include <arm_neon.h>

void test(signed int *output)
{
int16_t * out = (int16_t *) output;
{
  int16x4_t a = {0, };
  int16x4_t b = {1, };
  int16x4x4_t z;
  z.val[0] = vadd_s16(a, b);
  z.val[1] = vadd_s16(a, b);
  z.val[2] = vsub_s16(a, b);
  z.val[3] = vadd_s16(a, b);

vst4_lane_s16(&out[0]+0*4, z, 0);
vst4_lane_s16(&out[8]+0*4, z, 1);

}
}

$ arm-linux-gnueabi-gcc -mfloat-abi=softfp -mfpu=neon -O1 -Wall -o insn-unsat-constr.o -c insn-unsat-constr.c
insn-unsat-constr.c: In function ‘test’:
insn-unsat-constr.c:19:1: error: insn does not satisfy its constraints:
(insn 40 38 26 2 /usr/lib/gcc/arm-linux-gnueabi/4.5.2/include/arm_neon.h:10277 (set (reg:OI 95 d16 [orig:152 __b ] [152])
(mem/s/c:OI (pre_dec:SI (reg/f:SI 3 r3 [151])) [0 __b+0 S32 A64])) 786 {*neon_movoi} (expr_list:REG_INC (reg/f:SI 3 r3 [151])
(nil)))
insn-unsat-constr.c:19:1: internal compiler error: in reload_cse_simplify_operands, at postreload.c:402
Please submit a full bug report,
with preprocessed source if appropriate.
See <file:///usr/share/doc/gcc-4.5/README.Bugs> for instructions.

$ arm-linux-gnueabi-gcc -v
Using built-in specs.
COLLECT_GCC=arm-linux-gnueabi-gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/arm-linux-gnueabi/4.5.2/lto-wrapper
Target: arm-linux-gnueabi
Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro 4.5.2-5ubuntu2~ppa1' --with-bugurl=file:///usr/share/doc/gcc-4.5/README.Bugs --enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-4.5 --enable-shared --enable-multiarch --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/arm-linux-gnueabi/include/c++/4.5.2 --libdir=/usr/lib --enable-nls --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-plugin --enable-gold --enable-ld=default --with-plugin-ld=ld.gold --enable-objc-gc --disable-sjlj-exceptions --with-arch=armv7-a --with-float=softfp --with-fpu=vfpv3-d16 --with-mode=thumb --disable-werror --enable-checking=release --program-prefix=arm-linux-gnueabi- --includedir=/usr/arm-linux-gnueabi/include --build=i486-linux-gnu --host=i486-linux-gnu --target=arm-linux-gnueabi --with-headers=/usr/arm-linux-gnueabi/include --with-libs=/usr/arm-linux-gnueabi/lib
Thread model: posix
gcc version 4.5.2 (Ubuntu/Linaro 4.5.2-5ubuntu2~ppa1)

Related branches

lp://staging/~linaro-toolchain-dev/gcc-linaro/lp-744754-neon-ice

Rejected for merging into lp://staging/gcc-linaro/4.5

Michael Hope: Disapprove on 2011-07-04

Ramana Radhakrishnan (community): Needs Fixing on 2011-05-03

lp://staging/~ramana/gcc-linaro/fix-lp-744754-46

Merged into lp://staging/gcc-linaro/4.6 at revision 106764

Ulrich Weigand (community): Approve on 2011-07-01

lp://staging/~ramana/gcc-linaro/fix-lp-744754-45

Merged into lp://staging/gcc-linaro/4.5 at revision 99519

Ulrich Weigand (community): Approve on 2011-07-01

Revision history for this message

In GCC Bugzilla #48325, Luke Kim (nereusuj) wrote on 2011-03-29:

Download full text (3.5 KiB)

Created attachment 23794
preprocessed file

I have following error while building neon optimized code.

$ cat insn-unsat-constr.c
#include <arm_neon.h>

vst4_lane_s16(&out[0]+0*4, z, 0);
vst4_lane_s16(&out[8]+0*4, z, 1);

}
}

$ arm-none-linux-gnueabi-gcc -mfloat-abi=softfp -mfpu=neon -O1 -o insn-unsat-constr.o -c insn-unsat-constr.c
insn-unsat-constr.c: In function 'test':
insn-unsat-constr.c:19:1: error: insn does not satisfy its constraints:
(insn 40 38 26 2 /scratchbox/compilers/arm-linux-gnueabi-gcc4.5.1-2010.09-50/bin/../lib/gcc/arm-none-linux-gnueabi/4.5.1/include/arm_neon.h:10277 (set (reg:OI 95 d16 [orig:152 __b ] [152])
(mem/s/c:OI (pre_dec:SI (reg/f:SI 3 r3 [151])) [0 __b+0 S32 A64])) 740 {*neon_movoi} (expr_list:REG_INC (reg/f:SI 3 r3 [151])
(nil)))
insn-unsat-constr.c:19:1: internal compiler error: in reload_cse_simplify_operands, at postreload.c:403
Please submit a full bug report,
with preprocessed source if appropriate.

$ arm-none-linux-gnueabi-gcc -v
Using built-in specs.
COLLECT_GCC=/scratchbox/compilers/arm-linux-gnueabi-gcc4.5.1-2010.09-50/bin/arm-none-linux-gnueabi-gcc
COLLECT_LTO_WRAPPER=/scratchbox/compilers/arm-linux-gnueabi-gcc4.5.1-2010.09-50/bin/../libexec/gcc/arm-none-linux-gnueabi/4.5.1/lto-wrapper
Target: arm-none-linux-gnueabi
Configured with: /scratch/nathan/arm-lite/src/gcc-4.5-2010.09/configure --build=i686-pc-linux-gnu --host=i686-pc-linux-gnu --target=arm-none-linux-gnueabi --enable-threads --disable-libmudflap --disable-libssp --disable-libstdcxx-pch --enable-extra-sgxxlite-multilibs --with-arch=armv5te --with-gnu-as --with-gnu-ld --with-specs='%{save-temps: -fverbose-asm} %{funwind-tables|fno-unwind-tables|mabi=*|ffreestanding|nostdlib:;:-funwind-tables} -D__CS_SOURCERYGXX_MAJ__=2010 -D__CS_SOURCERYGXX_MIN__=9 -D__CS_SOURCERYGXX_REV__=50 %{O2:%{!fno-remove-local-statics: -fremove-local-statics}} %{O*:%{O|O0|O1|O2|Os:;:%{!fno-remove-local-statics: -fremove-local-statics}}}' --enable-languages=c,c++ --enable-shared --enable-lto --enable-symvers=gnu --enable-__cxa_atexit --with-pkgversion='Sourcery G++ Lite 2010.09-50' --with-bugurl=https://support.codesourcery.com/GNUToolchain/ --disable-nls --prefix=/opt/codesourcery --with-sysroot=/opt/codesourcery/arm-none-linux-gnueabi/libc --with-build-sysroot=/scratch/nathan/arm-lite/install/arm-none-linux-gnueabi/libc --with-gmp=/scratch/nathan/arm-lite/obj/host-libs-2010.09-50-arm-none-linux-gnueabi-i686-pc-linux-gnu/usr --with-mpfr=/scratch/nathan/arm-lite/obj/host-libs-2010.09-50-arm-none-linux-gnueabi-i686-pc-linux-gnu/usr --with-mpc=/scratch/nathan/arm-lite/obj/host-libs-2010.09-50-arm-none-linux-gnueabi-i686-pc-linux-gnu/usr --with-ppl=/scratch/nathan/arm-lite/obj/host-libs-2010.09-50-arm-none-linux-gnueabi-i686-pc-linux-gnu/usr --with-host-libstdcxx='-static-libgcc -Wl,-Bstatic,-lstdc++,-Bdynamic -lm' --with-cloog=/scratch/nathan/arm-lite/obj/host-libs-2010.09-50-arm-none-linu...

Created attachment 23794
preprocessed file

I have following error while building neon optimized code.

$ cat insn-unsat-constr.c 
#include <arm_neon.h>

void test(signed int *output)
{ 
	int16_t * out = (int16_t *) output;
	{
		int16x4_t a = {0, };
		int16x4_t b = {1, };
		int16x4x4_t z;
		z.val[0] = vadd_s16(a, b); 
		z.val[1] = vadd_s16(a, b); 
		z.val[2] = vsub_s16(a, b); 
		z.val[3] = vadd_s16(a, b); 
		
		vst4_lane_s16(&out[0]+0*4, z, 0);
		vst4_lane_s16(&out[8]+0*4, z, 1);
		
	}
}

$ arm-none-linux-gnueabi-gcc -mfloat-abi=softfp -mfpu=neon -O1 -o insn-unsat-constr.o -c insn-unsat-constr.c
insn-unsat-constr.c: In function 'test':
insn-unsat-constr.c:19:1: error: insn does not satisfy its constraints:
(insn 40 38 26 2 /scratchbox/compilers/arm-linux-gnueabi-gcc4.5.1-2010.09-50/bin/../lib/gcc/arm-none-linux-gnueabi/4.5.1/include/arm_neon.h:10277 (set (reg:OI 95 d16 [orig:152 __b ] [152])
        (mem/s/c:OI (pre_dec:SI (reg/f:SI 3 r3 [151])) [0 __b+0 S32 A64])) 740 {*neon_movoi} (expr_list:REG_INC (reg/f:SI 3 r3 [151])
        (nil)))
insn-unsat-constr.c:19:1: internal compiler error: in reload_cse_simplify_operands, at postreload.c:403
Please submit a full bug report,
with preprocessed source if appropriate.

Revision history for this message

Luke Kim (nereusuj) wrote on 2011-03-29:

Source code Edit (363 bytes, text/plain)

Revision history for this message

Luke Kim (nereusuj) wrote on 2011-03-29:

preprocessed file Edit (393.9 KiB, text/plain)

Revision history for this message

In GCC Bugzilla #48325, Mikpe (mikpe) wrote on 2011-03-29:

That's a heavily modified compiler by CodeSourcery. Please reproduce with a vanilla FSF GCC, or report the problem to CodeSourcery as their compiler clearly directs you to do (see the --with-bugurl= setting).

Revision history for this message

In GCC Bugzilla #48325, Ibolton (ibolton) wrote on 2011-03-29:

I get the same thing when I use r171282 of FSF 4.5 branch.

arm-none-linux-gnueabi-gcc pr48325.c -mfloat-abi=softfp -mfpu=neon -O1
pr48325.c: In function 'test':
pr48325.c:19:1: error: insn does not satisfy its constraints:
(insn 40 38 26 2 /work/ianbol01/cross-build/gcc45-r171282-thumb/arm-none-linux-gnueabi/tools/lib/gcc/arm-none-linux-gnueabi/4.5.3/include/arm_neon.h:10277 (set (reg:OI 95 d16 [orig:152 __b ] [152])
(mem/s/c:OI (pre_dec:SI (reg/f:SI 3 r3 [151])) [0 __b+0 S32 A64])) 731 {*neon_movoi} (expr_list:REG_INC (reg/f:SI 3 r3 [151])
(nil)))
pr48325.c:19:1: internal compiler error: in reload_cse_simplify_operands, at postreload.c:396

Here is the command-line just for cc1:

cc1 -quiet pr48325.c -mfloat-abi=softfp -mfpu=neon -marm -mcpu=cortex-a9 -O1

Doesn't work for thumb either.

It also fails on trunk.

There are two other bugs in flight that manifest in reload_cse_simplify_operands: PR48250 (broke on trunk for EABI, works on 4.5 for EABI) and PR42949 (works on EABI for trunk and gcc4.5, broke for OABI).

I do not know if they are duplicates of each other, or if there are two or more separate bugs causing this.

Revision history for this message

Michael Hope (michaelh1) wrote on 2011-03-30:

Confirmed in gcc-linaro-4.5-2011.03-0:

michaelh@ursa3:~/linaro/bugs$ /tools/toolchains/gcc-linaro-4.5-2011.03-0-armv7l-maverick-cbuild71-carina7-cortexa8r1/bin/gcc -mfpu=neon -O1 -c insn-unsat-constr.i
insn-unsat-constr.c: In function 'test':
insn-unsat-constr.c:19:1: error: insn does not satisfy its constraints:
(insn 40 38 26 2 /usr/lib/gcc/arm-linux-gnueabi/4.5.2/include/arm_neon.h:10277 (set (reg:OI 95 d16 [orig:152 __b ] [152])
(mem/s/c:OI (pre_dec:SI (reg/f:SI 3 r3 [151])) [0 __b+0 S32 A64])) 786 {*neon_movoi} (expr_list:REG_INC (reg/f:SI 3 r3 [151])
(nil)))
insn-unsat-constr.c:19:1: internal compiler error: in reload_cse_simplify_operands, at postreload.c:402

Does not occur in gcc-linaro-4.4-2010.10-0. Does not occur at -O0, but does at -O1, -O2, -O3.

The work around is to supply -fno-auto-inc-dec.

Changed in gcc-linaro:
status:	New → Triaged
importance:	Undecided → Medium

Revision history for this message

Michael Hope (michaelh1) wrote on 2011-03-30:

Also occurs in trunk in gcc 4.5.1 and gcc-4.5.2+svn171194.

Could you also report this in the GCC bugzilla please?

Revision history for this message

Luke Kim (nereusuj) wrote on 2011-03-30:

Upstream bug submitted http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48325

Revision history for this message

Chung-Lin Tang (cltang) wrote on 2011-03-30:

I also saw several other testsuite regressions on upstream trunk with a similar ICE too, will look at this.

Bug Watch Updater (bug-watch-updater) on 2011-03-30

Changed in gcc:
importance:	Unknown → Medium
status:	Unknown → Confirmed

Revision history for this message

Chung-Lin Tang (cltang) wrote on 2011-03-31:

#10

Correct comment #6, the regressions I saw on upstream trunk should be different from this; this is another bug.

Revision history for this message

Chung-Lin Tang (cltang) wrote on 2011-03-31:

#11

Upstream patch posted: http://gcc.gnu.org/ml/gcc-patches/2011-03/msg02204.html

Michael Hope (michaelh1) on 2011-03-31

Changed in gcc-linaro:
status:	Triaged → In Progress
assignee:	nobody → Chung-Lin Tang (cltang)

Revision history for this message

Michael Hope (michaelh1) wrote on 2011-04-15:

#12

Chung-Lin, could you ping this patch please?

Revision history for this message

Ira Rosen (irar) wrote on 2011-04-15: AUTO: Ira Rosen is out of the office. (returning 17/04/2011)

#13

I am out of the office until 17/04/2011.

Note: This is an automated response to your message "[Bug 744754] Re: ICE
in reload_cse_simplify_operands, at postreload.c:402 with neon optimized
code" sent on 15/4/2011 4:47:17.

This is the only notification you will receive while this person is away.

Revision history for this message

Michael Hope (michaelh1) wrote on 2011-06-09:

#14

No longer occurs in gcc-linaro-4.5-2011.05 and gcc-linaro-4.6-2011.05 due to the changes Richard made on general NEON accesses.

Richard is looking into pre/post inc/dec in general so we'll mark this as fixed.

Changed in gcc-linaro:
milestone:	none → 4.5-2011.06-0
status:	In Progress → Fix Committed

Michael Hope (michaelh1) on 2011-06-16

Changed in gcc-linaro:
status:	Fix Committed → Fix Released

Revision history for this message

Michael K. Edwards (m-k-edwards) wrote on 2011-06-29:

#15

I encountered this bug again with 4.6-2011.06-0 + patches. (See comment 3 on https://bugs.launchpad.net/gcc-linaro/+bug/803232 .) I will test with Chung-Lin's patch.

Revision history for this message

Michael K. Edwards (m-k-edwards) wrote on 2011-06-30:

#16

Updated "repaired" test case from bug 803232 Edit (2.8 KiB, text/plain)

Before Chung-Lin's patch, compiling jsimd_arm-min12.i fails:

build@ctbu-bld5:~/stuff$ ./compile.sh jsimd_arm-min12.i
jsimd_arm-min12.i: In function 'jsimd_idct_ifast':
jsimd_arm-min12.i:73:1: error: insn does not satisfy its constraints:
(insn 113 21 22 2 (set (mem/s/c:XI (post_inc:SI (reg/f:SI 4 r4 [184])) [0 MEM[(struct int8x8x4_t *)&coef].__o+0 S64 A128])
        (reg:XI 75 s12)) jsimd_arm-min12.i:40 757 {*neon_movxi}
     (expr_list:REG_INC (reg/f:SI 4 r4 [184])
        (nil)))
jsimd_arm-min12.i:73:1: internal compiler error: in reload_cse_simplify_operands, at postreload.c:403