<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/80052>80052</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            RISCV64 miscompile at -O2/-O1
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          patrick-rivos
      </td>
    </tr>
</table>

<pre>
    Testcase:
```c
int printf(const char *, ...);
int a[10000];
int b, c, d, e, f;
char g, h;
int j[100][100];
int m(long n) {
  b = ((b >> 4) ^ (b ^ n));
  b = ((b >> 4)) ^ a[(b ^ 0x0f) & 0x0F];
  b = ((b >> 4)) ^ a[(b ^ 0x0f) & 0x0F];
  b = ((b >> 4)) ^ a[(b ^ 0x0f) & 0x0F];
  printf("%s %lX\n", &g, b ^ 0xFFFFFFFFUL);
  return 0;
}
int main() {
  int i = 0;
  for (; c < 256; c++)
    a[c] = c;
  volatile int k = 3;
  h = 0;
  for (; (h <= 4); h += 1) {
    int *l = &d;
    *l = k;
 k = 0;
  }
  for (; i < 6; i++)
    for (; e < 1; e++) {
 m(j[i][e]);
      if (f)
        printf("%d%d\n", i, e);
 }
  return m(d);
}
```
Commands:
```bash
> /scratch/tc-testing/llvm-jan-24/build/bin/clang -O2 red.c -o user-config-O2.out
> QEMU_CPU=rv64 /scratch/tc-testing/llvm-jan-24/build/bin/qemu-riscv64 user-config-O2.out
 FFFFFFF0
 FFFFFFFC
> /scratch/tc-testing/llvm-jan-24/build/bin/clang -O0 red.c -o user-config-O0.out
> QEMU_CPU=rv64 /scratch/tc-testing/llvm-jan-24/build/bin/qemu-riscv64 user-config-O0.out
 FFFFFFF0
 FFFFFFFF
```
This raw testcase differs at -O2, but after feeding it through bugpoint, I got a .bc file that differs at -01.
```bash
> /scratch/tc-testing/llvm-jan-24/build/bin/clang red.c -O2 -o user-config.bc -emit-llvm -c
> /scratch/tc-testing/llvm-jan-24/build/build-llvm-linux/bin/bugpoint user-config.bc --run-llc
> /scratch/tc-testing/llvm-jan-24/build/build-llvm-linux/bin/clang bugpoint-reduced-named-md.bc -O0 -o bugpoint-O0.out
> QEMU_CPU=rv64 /scratch/tc-testing/llvm-jan-24/build/bin/qemu-riscv64 bugpoint-O0.out
 FFFFFFF0
 FFFFFFFF
> /scratch/tc-testing/llvm-jan-24/build/build-llvm-linux/bin/clang bugpoint-reduced-named-md.bc -O1 -o bugpoint-O1.out
> QEMU_CPU=rv64 /scratch/tc-testing/llvm-jan-24/build/bin/qemu-riscv64 bugpoint-O1.out
 FFFFFFF0
 FFFFFFFC
```
[bugpoint.zip](https://github.com/llvm/llvm-project/files/14103541/bugpoint.zip)

</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzMVllv4zYQ_jX0y0ACRR22HvQQ2xGwQIv02BR9KyiSkphIlEtS2W1_fUFalqUku9trgzUUHZzhN_PNxVBjZKOEKFC6R-lxQ0fbDro4Uaslewy0fBrMphr4H8V7YSyjRqD4BuEjwjcow-eLnb-lsnDSUtkakR0blLHAWqoBkRtEDhCGISI5ivdXbYrSfYQxxig9rgSV28DcjbubcLd61vCojVtrV7seznAObH5ZyntEdt2gGlCI5IC2kwigAhQfAZEdIjv3foviW0i8UnoL58X01m9bUvjMxstex3Dejz_i2gtI5t7LpX_fLtacUkQIIqkBRNLuV5QelF84uG0-GRewcvrdf7cOlhZ21ArwvIS2x0VyqFTeyCozTiI9GbxAqgftycV7YIDiA5A08x-I7P2VXzTBM2UoPXoQtgB5GjpqZSe8jUcvjhfi9nNWEdk5-cGpJGeWbgPZu4XoGYczC0RuuikrGV-gwlXyeF1-fGF9DtbKEenpe_LyFfILTeE1I_86ay7cdM3hGkie20e4xyp9nkjt4OqVDfd7ViPc_10rRE5NvIBb0JnqwjnAlzqzyjxozp-Hoe-p4ublIKqoaael2PVtaZimlrWIlJYFVhgrVYNI2XVPffBAVUASRMpqlB13T1eAJeuoaiC4I6AFDxkEA4xG6IANqpZNcEfCYbRXIz_efn__2-GHexQf9VOW_Eujv4t-DLQ0zEF8yhxMfYXXn4f_izH-BGP8tozxFxmXr5bF-1Ya0PQD2OmgAi7rWmgD1Lp8-hE1WqC1FRpqIbhUDUgLttXD2LRQjc1pkMo6xXfQDBYohBWD2g0J21K7AsRR-NWqb8rDHXmWC-dNIHppA4cBAfsP5tzTwwSdVOPH2YNLFF7YDfSogq77GjbPrC-WAy34yAQPFO0FD3ruzd9hF4xZ5w2q8lVbXyjJN49KtI5K9IZRif72aFo3Kkr3F5DwT3nyB82utfbkJzopESkbaduxCtnQT65dPDzp4UEwi0jputIgUkZJhOM0iRal61EvR9SGFzHP45xuRBFtcZYlaRzlm7bACcOCZ4TUnPIt223JNq8zUdXVNoq2u2ojC4JJgqMYE4x3cR4mmOd5ss3yTPCqimKUYNFT2YXOtXDQzUYaM4pih3FKNh2tRGf8_9WEKPEBvNCdiOlxowtPpxobgxLcSWPNFcVK24nip3c_H37JEuilYUN_ckPoMsjK4C7ajLor_nHUvA8ubN7HvwIAAP__8eNa6w">