https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103317
Bug ID: 103317
Summary: Spec 2017 benchmark blender_r fails with -Ofast on
PowerPc (power9, power10)
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: meissner at gcc dot gnu.org
Target Milestone: ---
Created attachment 51832
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=51832&action=edit
Preprocessed .i file that shows the bug (gzipped).
As of November 17th, the current trunk compiler for GCC 12 fails when compiling
the Spec 2017 benchmark blender_r for PowerPC using -Ofast. I see failures for
both power9 and power10 systems. Here is the traceback:
libpng/png.c: In function 'png_build_gamma_table':
libpng/png.c:2872:1: error: definition in block 19 does not dominate use in
block 18
2872 | }
| ^
for SSA_NAME: _57 in statement:
shift_48 = PHI <_57(18), _58(19)>
PHI argument
_57
for PHI node
shift_48 = PHI <_57(18), _58(19)>
during GIMPLE pass: phiopt
libpng/png.c:2872:1: internal compiler error: verify_ssa failed
0x10c5f64b verify_ssa(bool, bool)
/home/meissner/fsf-src/trunk-2021-11-17/gcc/tree-ssa.c:1211
0x1080e97f execute_function_todo
/home/meissner/fsf-src/trunk-2021-11-17/gcc/passes.c:2049
0x1080f613 execute_todo
/home/meissner/fsf-src/trunk-2021-11-17/gcc/passes.c:2096
Please submit a full bug report,
with preprocessed source if appropriate.
I see it with -O2, -O3, and -Ofast, using -mcpu=power8, -mcpu=power9, and
-mcpu=power10 on PowerPC little endian systems. It did compile with the
compiler I checked out on November 4th.
I will attach the .i file compressed with gzip.
