| Issue |
89833
|
| Summary |
[RISC-V] rv64gcv miscompile at `-O2 -flto` with pass `gather/scatter lowering`
|
| Labels |
new issue
|
| Assignees |
|
| Reporter |
patrick-rivos
|
Testcase:
```c
short a;
long long b;
int c = 4;
signed char d[10], e[10];
int main() {
for (long h = 0; h < 10; ++h)
d[h] = 1;
for (int h = 0; h < 10; h += c || a)
e[h] = 256 / d[h];
__builtin_printf("%d\n", e[1]);
}
```
Commands:
```bash
> /scratch/tc-testing/tc-apr-23/build-rv64gcv/build-llvm-linux/bin/clang -fwrapv -march=rv64gcv -flto -O2 red.c -o red.out
> /scratch/tc-testing/tc-apr-23/build-rv64gcv/bin/qemu-riscv64 red.out
1
> /scratch/tc-testing/tc-apr-23/build-rv64gcv/build-llvm-linux/bin/clang -fwrapv red.c -o red.out
> /scratch/tc-testing/tc-apr-23/build-rv64gcv/bin/qemu-riscv64 red.out
0
```
Discovered/tested using cebc9609d8cdc6f488693cd8e4a616b935b38d2c (not bisected)
Found via fuzzer.
flto opt-bisect-limit points to `pass (70) RISC-V gather/scatter lowering on function (main)`
![]()
_______________________________________________
llvm-bugs mailing list
llvm-bugs@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-bugs
