https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115631
Bug ID: 115631
Summary: [15 Regression] GCN: [-PASS:-]{+FAIL:+}
c-c++-common/torture/builtin-arith-overflow-6.c -O2
execution test
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Keywords: testsuite-fail
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: tschwinge at gcc dot gnu.org
CC: ams at gcc dot gnu.org, rsandifo at gcc dot gnu.org
Target Milestone: ---
Target: GCN
With commit r15-1579-g792f97b44ffc5e6a967292b3747fd835e99396e7 "Add a
late-combine pass [PR106594]", I see for GCN target testing (tested
'-march=gfx908') regress for both C, C++:
@@ -191300,7 +191300,7 @@ PASS:
c-c++-common/torture/builtin-arith-overflow-6.c -O0 (test for excess er
PASS: c-c++-common/torture/builtin-arith-overflow-6.c -O0 execution test
UNSUPPORTED: c-c++-common/torture/builtin-arith-overflow-6.c -O1
PASS: c-c++-common/torture/builtin-arith-overflow-6.c -O2 (test for
excess errors)
[-PASS:-]{+FAIL:+} c-c++-common/torture/builtin-arith-overflow-6.c -O2
execution test
UNSUPPORTED: c-c++-common/torture/builtin-arith-overflow-6.c -O3 -g
UNSUPPORTED: c-c++-common/torture/builtin-arith-overflow-6.c -Os
spawn -ignore SIGHUP [...]/build-gcc/gcc/gcn-run
./builtin-arith-overflow-6.exe
GCN Kernel Aborted
Kernel aborted
FAIL: c-c++-common/torture/builtin-arith-overflow-6.c -O2 execution test
With '-fno-late-combine-instructions', it's back to PASS.
The diff between good ('-fno-late-combine-instructions') vs. bad
('-flate-combine-instructions') of 'builtin-arith-overflow-6.s' as well as
'-fdump-rtl-all' is big, so I'm not able to directly pinpoint one specific
issue.
I however do observe a number of instances as follows (good vs. bad):
[...]
s_mov_b64 exec, -1
[...]
- s_mov_b32 s12, 0
- v_writelane_b32 v0, s12, 0
s_mov_b64 exec, 1
+ v_mov_b32 v0, 0
flat_store_dword v[18:19], v0
[...]
Might that "move across 'exec'" be in error?
