https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117682
Bug ID: 117682
Summary: [15 Regression] rv64gcv_zvl256b miscompile since
r15-3228-g771256bcb9d
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: patrick at rivosinc dot com
Target Milestone: ---
Testcase:
signed char a = 9;
int main() {
for (char e = 0; e < 20; e++)
for (char f = 0; f < 7; f++)
a *= 57;
if (a != 41)
return 1;
}
Commands:
> riscv64-unknown-linux-gnu-gcc -march=rv64gcv_zvl256b -O3
> -mrvv-vector-bits=zvl test.c -o user-config.out -fsigned-char
> -fno-strict-aliasing -fwrapv
> QEMU_CPU=rv64,vlen=256,rvv_ta_all_1s=true,rvv_ma_all_1s=true,v=true,vext_spec=v1.0,zve32f=true,zve32x=true,zve64d=true,zve64f=true,zve64x=true
> timeout --verbose -k 0.1 4
> /scratch/tc-testing/tc-compiler-fuzz-trunk/build-gcv/bin/qemu-riscv64
> user-config.out
> echo $?
1
> riscv64-unknown-linux-gnu-gcc -march=rv64gcv_zvl256b -O2
> -mrvv-vector-bits=zvl test.c -o user-config.out -fsigned-char
> -fno-strict-aliasing -fwrapv
> QEMU_CPU=rv64,vlen=256,rvv_ta_all_1s=true,rvv_ma_all_1s=true,v=true,vext_spec=v1.0,zve32f=true,zve32x=true,zve64d=true,zve64f=true,zve64x=true
> timeout --verbose -k 0.1 4
> /scratch/tc-testing/tc-compiler-fuzz-trunk/build-gcv/bin/qemu-riscv64
> user-config.out
> echo $?
0
Found via fuzzer
First bad commit: r15-3228-g771256bcb9d
Looks like a latent bug exposed by costing more patterns.
