<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/72046>72046</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [LoongArch] Broken code is generated after #71534
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            backend:loongarch
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          heiher
      </td>
    </tr>
</table>

<pre>
    For the test case below, broken code generated after #71534 crashes the program.

get.c
```c
unsigned int get(const unsigned char *box, unsigned int in)
{
    return box[in >> 24];
}
```

main.c
```c
extern unsigned int get(const unsigned char *box, unsigned int in);

static const unsigned char box[] = {
    0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b,
    0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
    0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85,
    0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
 0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5,
    0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a,
    0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
    0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0,
 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
    0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e,
    0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
    0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94,
 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
    0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68,
    0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16,
    0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
 0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17,
    0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
    0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88,
    0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
 0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c,
    0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
    0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9,
    0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
 0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6,
    0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
    0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5,
    0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
 0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0,
    0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
    0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc,
    0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
};

int main(int argc, char *argv[])
{
    return get(box, 0x80000000U);
}
```

## Before

get.ll
```bash
clang -target loongarch64 -O2 -S -o get.ll get.c -emit-llvm
```
```
define dso_local signext i32 @get(ptr nocapture noundef readonly %0, i32 noundef signext %1) local_unnamed_addr #0 {
  %3 = lshr i32 %1, 24
  %4 = zext i32 %3 to i64
  %5 = getelementptr inbounds i8, ptr %0, i64 %4
  %6 = load i8, ptr %5, align 1, !tbaa !2
  %7 = zext i8 %6 to i32
  ret i32 %7
}
```

get.s
```bash
clang -target loongarch64 -O2 -S -o get.ll get.c
```
```
get:                                    # @get
        bstrpick.d      $a1, $a1, 31, 24
        ldx.bu  $a0, $a0, $a1
        ret
```

## After

get.ll
```bash
clang -target loongarch64 -O2 -S -o get.ll get.c -emit-llvm
```
```
define dso_local signext i32 @get(ptr nocapture noundef readonly %0, i32 noundef signext %1) local_unnamed_addr #0 {
  %3 = lshr i32 %1, 24
  %4 = zext nneg i32 %3 to i64
  %5 = getelementptr inbounds i8, ptr %0, i64 %4
 %6 = load i8, ptr %5, align 1, !tbaa !2
  %7 = zext i8 %6 to i32
  ret i32 %7
}
```

get.s
```bash
clang -target loongarch64 -O2 -S -o get.ll get.c
```
```
get:                                    # @get
        srli.d  $a1, $a1, 24
        ldx.bu  $a0, $a0, $a1
        ret
```
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzsWMtu48oR_ZrWpiGB7OZzoYV9db0KkEWQ9aAfRYoZijSarYknXx-QPCVLnEcGiO9uDMMtktWnTp2uKpZlpqlrB6KjyJ9FftqZazyP4Xim7kxhZ0f_9fgyBhnPJCNNUTozkbTUj_8W6g9pw_iZBulGT7KlgYKJ5KVpIgUplC7TXGfSBTOdaVowXsPYBnM5iOQkkqf1b0vx4HCjSNZfXF-HhZ2X3RBlS1Goyo3DFOXtgTub2dWTHd9mQg8bukGoGsDl8_pBSikDxWsY5Lwlf-4GKfSfQv8pVSbyk9DPvOO04XTP-WK64Uek6S1SGORHcL-RWf5O0cTOye-hrLGI_CSFPsmHaJO3XM_wyZtP1zVJ1pX8uipcN25dLexyK9Qf90CFWR84C0NaV12va4bnGYDyCvbNBsgzg2ZdDTY2AM7AOANDjesq3wBlOTaCQaLWtQRwDkcajGp2WL0DJW85AjbsFrsqWNdArZkO4mq2dJIMAZdQFoAOa4qNdQG6oF-bLRAAUniuWDBcE4RSsLMc9zeMIEwFBgpCpFA8BVCBo8xx3yQPAgFew9qDv2VUeCG-hnBVtqFT8nnAnYUABQAzCJQAqGGhaJuKODINgJyF4Hix0cEuxdHVWyCCQcNHgzXF_QKAnoHBvM7uBaohTIqnFegQdjmWF3QVvPhtZVQ4HwP3FSc2-FsoSywYTqaotpUBgBoACgAJACxOIkfKWo6g2ABZ7grw6JEhipXl7gHghruNuhfIsXvOP1gRtwouNQiXgVZabug4PDAwLLkHwUGB5zmuU8Rf6m0GcZEjjgwMPBgpKKsQb8323ygNYYhzmjMITDyfPdaEi8jeC0RcGVxqcJtwT-VEgDfFcbqtQADwUNggnoKbGCcGUpEAVNbbyoDCDvFoXBdQtsLqAZQhPrMFKviMQb2BR0JoBQBK7j0s1EOTtnhago7iUoJ1ypXDvYl78TahiWsP_EtONSRAxm83jhPX1bZJF1C4hOeSUxIbGq5N7rFw4LZNWuPsE-45_PpgIITocd_gflk8lBgEquDWceYjjgbPc35bA61JNnQMHyyXGgAN1ygrzZnDDrdAlj1w8-XXA45I88qtgzNum9OamXDO8msfgpVYPacq96Z3ped57nGcmseseY4Tqpo_mtAucfFUZkL7ZZ2pfjpFrpMdRrj5Rb3-_PNhfPvpLCnmKUHLZ2rGQNvBuO83O62Zzust15uhlftoQktR9uM4tCa4c5HJ_d-V3P9D7ke5QiyLk3u6dHHf918u32fzeOmp6QaSfho_9aMzvVzmzbcoO62kyJI18NcY5DA68xqvgeQwXgdPjQxk_Dj0X6VQ6wQ27-GHjCPUPHfVckH_dB0GcyH_yXi__O-Q3E-xQuV6mWz76RxWAmod2lR2Z5MtNv-5kZx3xVF2xb1Rvhi1FKmnCw1xjqAb7Exukt2SQPOtG_MiW6DvEIqVymj8o_2SlKbv2kEu3IRKozVmXtXd9vKOZbXizST1zSbQjX_5Kwk0n-70YWnyK7kxn71equB__cyZjWQB49pOMbx27vPBi3k6zQzEwgf9cK4iqXv_drBX2CZsm7xvYsNwc_KTMnua_zn9XWUfU2XDQO1fVmq_K-3_rbQp9N0Pquxj6mvnj9rXujY7OqZFXZdlVZbp7nwscq0yr3Lv0lIltnIu99q4xmQJlVbVu-6oEqXTNFVJlRVpeqiz0uVNbZvKq7xqcpEldDFdf5gr6TCGdtdN05WOpUqyYtcbS_20fGmllDXuMw1e6Keb5kIpkZ924Tjv3ttrO4ks6bspTu94sYv98r3X3-ZdT_Ou_CSf777S6qYffqu1u4b-eI7xdRL6SagXoV7aLp6v9uDGi1AvS_2vy_41jP8iF4V6WUKYhHpZovhvAAAA___WvgT0">