<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/64278>64278</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            "fatal error: unknown codeview register D1_D2" when compiling with `-O1 -g -gcodeview` on armv7-windows
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
      </td>
    </tr>

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

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

<pre>
    ### Repro

Tested with LLVM 17.0.0-rc1.

```console
$ docker run --rm -v $(pwd):/repro -w /repro -it mstorsjo/llvm-mingw:latest armv7-w64-mingw32-clang -O1 -g -gcodeview -c reduced.c
fatal error: error in backend: unknown codeview register D1_D2
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: /opt/llvm-mingw/bin/clang --start-no-unused-arguments -target armv7-w64-mingw32 -rtlib=compiler-rt -unwindlib=libunwind -stdlib=libc++ -fuse-ld=lld --end-no-unused-arguments -O1 -g -gcodeview -c reduced.c
1.      <eof> parser at end of file
2.      Code generation
3.      Running pass 'Function Pass Manager' on module 'reduced.c'.
4.      Running pass 'ARM Assembly Printer' on function '@transpose_M_win5'
 #0 0x00007f85c8ffeeff llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0x88aeff)
 #1 0x00007f85c8ffcf2c llvm::sys::CleanupOnSignal(unsigned long) (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0x888f2c)
 #2 0x00007f85c8f06457 llvm::CrashRecoveryContext::HandleExit(int) (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0x792457)
 #3 0x00007f85c8ff49c2 llvm::sys::Process::Exit(int, bool) (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0x8809c2)
 #4 0x0000561f6dbd3f66 (/opt/llvm-mingw/bin/clang+0x12f66)
 #5 0x00007f85c8f195ca llvm::report_fatal_error(llvm::Twine const&, bool) (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0x7a55ca)
 #6 0x00007f85cae39b6d llvm::MCRegisterInfo::getCodeViewRegNum(llvm::MCRegister) const (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0x26c5b6d)
 #7 0x00007f85c9c1fb24 (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0x14abb24)
 #8 0x00007f85c9c2f665 (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0x14bb665)
 #9 0x00007f85c9c33245 (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0x14bf245)
#10 0x00007f85c9ba458b llvm::DebugHandlerBase::endFunction(llvm::MachineFunction const*) (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0x143058b)
#11 0x00007f85c9b96619 llvm::AsmPrinter::emitFunctionBody() (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0x1422619)
#12 0x00007f85cb6a3e93 (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0x2f2fe93)
#13 0x00007f85c94f04a0 (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0xd7c4a0)
#14 0x00007f85c9199c4a llvm::FPPassManager::runOnFunction(llvm::Function&) (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0xa25c4a)
#15 0x00007f85c9199dd9 llvm::FPPassManager::runOnModule(llvm::Module&) (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0xa25dd9)
#16 0x00007f85c919b1a0 llvm::legacy::PassManagerImpl::run(llvm::Module&) (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0xa271a0)
#17 0x00007f85cf6cd9f0 clang::EmitBackendOutput(clang::DiagnosticsEngine&, clang::HeaderSearchOptions const&, clang::CodeGenOptions const&, clang::TargetOptions const&, clang::LangOptions const&, llvm::StringRef, llvm::Module*, clang::BackendAction, llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem>, std::unique_ptr<llvm::raw_pwrite_stream, std::default_delete<llvm::raw_pwrite_stream>>) (/opt/llvm-mingw/bin/../lib/libclang-cpp.so.17git+0x1e5f9f0)
#18 0x00007f85cfb58709 (/opt/llvm-mingw/bin/../lib/libclang-cpp.so.17git+0x22ea709)
#19 0x00007f85ce28a039 clang::ParseAST(clang::Sema&, bool, bool) (/opt/llvm-mingw/bin/../lib/libclang-cpp.so.17git+0xa1c039)
#20 0x00007f85cfb5785d clang::CodeGenAction::ExecuteAction() (/opt/llvm-mingw/bin/../lib/libclang-cpp.so.17git+0x22e985d)
#21 0x00007f85d06d70f1 clang::FrontendAction::Execute() (/opt/llvm-mingw/bin/../lib/libclang-cpp.so.17git+0x2e690f1)
#22 0x00007f85d0657303 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/llvm-mingw/bin/../lib/libclang-cpp.so.17git+0x2de9303)
#23 0x00007f85d076dde3 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/llvm-mingw/bin/../lib/libclang-cpp.so.17git+0x2effde3)
#24 0x0000561f6dbd538c cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/llvm-mingw/bin/clang+0x1438c)
#25 0x0000561f6dbce84d (/opt/llvm-mingw/bin/clang+0xd84d)
#26 0x00007f85d028241d (/opt/llvm-mingw/bin/../lib/libclang-cpp.so.17git+0x2a1441d)
#27 0x00007f85c8f06347 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/opt/llvm-mingw/bin/../lib/libLLVM-17git.so+0x792347)
#28 0x00007f85d02828bc (/opt/llvm-mingw/bin/../lib/libclang-cpp.so.17git+0x2a148bc)
#29 0x00007f85d024798e clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/opt/llvm-mingw/bin/../lib/libclang-cpp.so.17git+0x29d998e)
#30 0x00007f85d024835d clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const (/opt/llvm-mingw/bin/../lib/libclang-cpp.so.17git+0x29da35d)
#31 0x00007f85d025446c clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/opt/llvm-mingw/bin/../lib/libclang-cpp.so.17git+0x29e646c)
#32 0x0000561f6dbd3121 clang_main(int, char**, llvm::ToolContext const&) (/opt/llvm-mingw/bin/clang+0x12121)
#33 0x0000561f6dbcdfc5 main (/opt/llvm-mingw/bin/clang+0xcfc5)
#34 0x00007f85c83c0083 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x24083)
#35 0x0000561f6dbce00e _start (/opt/llvm-mingw/bin/clang+0xd00e)
```

### `reduced.c`

```c
#include <arm_neon.h>

int64x2_t aom_vtrn2q_s64(int64x2_t a, int64x2_t b) {
  return vcombine_s64(vget_high_s64(a), vget_high_s64(b));
}

void transpose_M_win5(int64_t *M, int64_t *M_trn) {
  int64x2_t row23 = vld1q_s64(M_trn);
  int64x2_t row33 = vld1q_s64(M_trn + 3);
 vst1q_s64(M, aom_vtrn2q_s64(row23, row33));
}
```

### Additional info

Can also be reproduced by compiling either libwebp or aom from source.

<details>
 <summary>Details</summary>

```Dockerfile
# Build with:
# docker build --build-arg ARCH=armv7 -t llvm-mingw .
# docker run --rm llvm-mingw tar -cf - /packaging | tar -xvf -
FROM mstorsjo/llvm-mingw:latest

# Supported architectures: x86_64, i686, aarch64 and armv7
ARG ARCH=armv7

# Install git
RUN apt-get update -qq && \
 apt-get install -qqy --no-install-recommends git && \
    apt-get clean -y && \
    rm -rf /var/lib/apt/lists/*

WORKDIR /build

# Clone libwebp
RUN git clone --depth 1 --recursive https://chromium.googlesource.com/webm/libwebp

# Clone aom
RUN git clone --depth 1 --recursive https://aomedia.googlesource.com/aom

# Compiler flags
ENV \
  CFLAGS="-g -gcodeview" \
  CXXFLAGS="-g -gcodeview" \
  LDFLAGS="-Wl,--pdb="

WORKDIR /build/libwebp/build-$ARCH

# Cross-compile libwebp for Windows
RUN cmake \
      -DCMAKE_BUILD_TYPE=Release \
 -DCMAKE_INSTALL_PREFIX="/packaging" \
 -DCMAKE_C_COMPILER=$ARCH-w64-mingw32-clang \
 -DCMAKE_CXX_COMPILER=$ARCH-w64-mingw32-clang++ \
 -DCMAKE_SYSTEM_NAME=Windows \
      -DCMAKE_SYSTEM_PROCESSOR=$ARCH \
 .. && \
    cmake --build . -- -j$(nproc) && \
    cmake --install .

WORKDIR /build/aom/build-$ARCH

# Cross-compile aom for Windows
RUN cmake \
      -DCMAKE_BUILD_TYPE=Release \
 -DENABLE_DOCS=OFF \
      -DENABLE_TESTDATA=OFF \
 -DENABLE_TOOLS=OFF \
      -DENABLE_EXAMPLES=OFF \
 -DCONFIG_AV1_HIGHBITDEPTH=0 \
      -DCONFIG_WEBM_IO=0 \
 -DCONFIG_RUNTIME_CPU_DETECT=0 \
 -DCMAKE_INSTALL_PREFIX="/packaging" \
 -DCMAKE_C_COMPILER=$ARCH-w64-mingw32-clang \
 -DCMAKE_CXX_COMPILER=$ARCH-w64-mingw32-clang++ \
 -DCMAKE_SYSTEM_NAME=Windows \
      -DCMAKE_SYSTEM_PROCESSOR=$ARCH \
 .. && \
    cmake --build . -- -j$(nproc) && \
    cmake --install .
```
</details>

/cc @mstorsjo 
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzsWl1zm7zy_zTkRoMHBOblIheOX9qckzQZ20-fnitGSALrKUiuJOzk2_9HgG3kOE3a5pyr_0wnNdJq97er1e6KBSnFSk7ptTO-ccazK9TojZDX3yvKFGq-06tckOdrBwbdP7CkWykcb-Z4k-7vmipNCdgzvQF3d1_vgR-PvJHnSuyPhnRO5HX_sOBKVLQfhSEgAn-nEsiGA9eVNXB3wIGhA5PtnjgwdYKJAxfSyAXuHpx-Mw1qpYVU_wgHLqpqV7s14-XeCSYV0lRpgGS9i919FHYTAXRxhXgJ3AcfuCVwSywI3TG6By4GkpIGUzLCHbICaVQBKqWQTjDpfgDGQY7wd8qJGWv4dy72HBy5SFoypakEMz-bwY7P4918spoD1eQ10wCBvCmBpFshNdACbLTeqk5DBy5KpjdNPsKi7hU66LWV4h-KtQMXTKmGKgcuAOIEMI6rhlCgNxRgidSmhaclwtSBU7BtLYWpUpQAJRrZDZuVSCmBGTJbZwyvsGRb3W_YSiP8HZCm3hpk7ZA3crz0UYpSohogWTY15doAN_shttreALjIGXfgore2qzSS2uXCbXijKHGPDICrkSzphZ0CrtQVy51ghkW9ZRWVrtTAbfiecdJNVCzvHoGr9GkMO_DGgTfALRpF3YqY0YoA16WcXMbwDm8wvpw6wZSKwgnmYIukohIgDSgnQBSgYAePhoZyKggFJeVUIs0E72YCM7NsOGe8BFukFHBgvGg4NiTg0QzcI45KKh0YA8FBLUhTUUN1QgPjfpPCS9wmy3swUYrWefUMHiXj-sisOAhyYOyEnpaIq61QNLvP9oyPzWjLFzgw8ID35HmeFxfJGCdFQWlRgNYfg4kTTNSz6n60ElpvWXcul5yIJNpnQmlJUe3AyLgd49qBKXBg8jOfGY3MOMu7vyaiuH5cMj1SwoE33lOSIFoUJi4c4fpncHEB8SW404oi3mwf-IqVHFUOTBreRj8CKsHLDwGXFBBb4KANzovCcTwANzWndkmx2FH5PBVc0yfdzXxGnFR0_sS0A5OPsV2cwnAcW_CCM9uFKYaXt7qNI93DENQU5EJUH2I7L8XQAhf24MaRX0QkJ0ERRW-JaWNOy9CHRRRZ_Ma2sn46xmigbBeWszbyZ13kH3r0es84BSZ96d6jP0jzGI3HGFlIoyFSRIM0j8gA6f102aeaW16Ibqyk2oSdr4zul7T80tQW-NMKA7hV4k9hwwiP84hYuOMh7hT7RQ7DP5XjhyjPTUEwkJPYcsxOj_9cTp5H0diSk9pyggCGHyGngOFJjolgVsRNcxSOk3yw3zOaN2UXEOQNUrQbpZwc0oe91whvGKfH1NK77OQDXNUPA2-c5BZ238aeRpGfDrBPVH3IRB3qmukDtBtBnltEHwAMwshPLWBW6M0jFNA0-GOnL2BB08CSY8XQNCy8EHl_KofEOESeJSa0xPhpisNh9Fo8mhLiUEF0Aa3hD_yii5wGow8wPoJjHCIL7PgcLCHpO8DetyWP7c390AcBJcR2kugMaO4jbwC0oiXCz30OPEG-rbfVEfZ_EW7snzmBFWCLCJO08ECX87rUXDN9011RHhq9bUyeHkzPGCq5UJphNecl47TPZAOSzxQRKlcUSbx52BonUVbSG5CafPOJ8jeo1m2J_wbRHeLlJZKTYVdaMl4uaWEPH-w9OWPYG2HSu_lwyS3XslFsR5e0mHL9qKUTTE_Tu6IvcxasoqtnpWntBHPDQmnSzTSc_Whotj1baWre7V4yTbND5TtYRGiBmkpnhFZU0zcWBvNW5i-6UKu_i7fbkRKj1pW64EjHRVrYjmRl0CIfJ7H3McIgpCj27ENmpVEKE-QF6XCzHs19arJa2866ojWyKq3frLheAYp87AUWTuidGSVOxuSCw_dO1dfCFDeaHvzs13PZ62ZMkzGx4A0zLfEiEnuFP4S3kOYCcXT6Ib6PREaj1Ct8Cxm0kY3jwAtsw3WX-FuuNOKYXrbd66r8Rjh9DT2haeBZCRwGFvo4IoRa6HucJyV2AqOXmF8o-Rsl16s2LwpCbdTnt6NxkGCAsZ_ViNk5aSIlejaRM5jiDZKngrALa_YYnIKdYOR94Ae3rTBIsIVvbOPDNAnJ-_mRJLSdP7I2CSYw9N9k9z7bIj8MfVtYfH5rD8L33dqXDV-hglbP1gYcXr5kst0EY98Oevo7Uf7ixT4IY0uD5NxcSY4_zFxJbm91agsL4zShwwNEJNsd6rzulKAXEWoq6hpxYh-ps4WG4LUK4iekk7P7-m9cf18zRkrSNKFDY1hvz4wxksBOIu8xxr9Erl63xL9EfseUfq1QqlFVfaVYi75MnR5LkC1ipmLpX9y813h9LfLfMyEK7EQX2IkOjsMwwq_BnQ1-W4H6QoR-zfT_QxN-UD5IaRRG1iE8vmk8vi3zYV8dHDLCAfQGyfZQTGyt10JUfTAbuNav5ADoQ6suOL5ePOQAUuAxMGjezxQX2HpXElj34CTAnpcEIMuMsbK205ANBHSGfEqiLArdivHmyS1509vW2DTq7Bl6iZVdgxfZy_Mo6Pj_QhLzvEFsOHTArLbYsbPmRN7pNf8Z0bF3dlx06Pw4wRTJOuNU8NHG-NhgGeM6Cp9gpgESdbbTksMfmYrCzhMOU_2r-f4xbzc8vulfgQFJdSM52GFR54zTfvmupDrbsHLTP7d3f1M4nI23L4pMkuv5OfFsCLDNgy87ER26zNh5cn-E1z9nWvIzjCf0UuyNJYMZ2FXEPyh7WHOEcbYkeGUJcOANCKyFO6VPNG0v7dyyLQQz0zJ-Vf-f-8KEEGYCE6oA44XVb50iDlClBMgpaNt7rcuA_Bl0jTLGS0CZ3lAJKpbvab4FQhqYoJCi7ruAdmc2mBKqEavU0X-MW6mmrpF8doL57DA7deDiNHzRQ2dtM_fUDjPa3DSs6jrEx36iGe77vnk767rt_y6SJZgsp5-dYNb2BIGrwemIgdGL5ce28YBKIwlcXAAXOHCxRfg7Ko1ZnHjaTT3tCuB2nBbLh_s32shnWwRWzXYrpKYEIIk3TFOsG0nbZmgXZ1qXjZI2pyBDE4Vdz9Uo1PGZLD9Zap7LaK8QVQVMvG8Hl399AWir3ZJq0GwJ0hS4P36ANkJHwBlP-4070LCegfvjxzNwXS7cfsSVFIu6ppwow_0lBwCOTHBFEQfu80UiWQNXFsbCO5NO-kiLuqDIlFZtT3sy1Ozvh-W_Z7dLs6bd7XOtp5Xg9OC2J70NTNxOuS6hW70Bvtlyihup2I6eNdHxRoqaNfWoFKKsaO_wXU99T_O6g3qScC4eifp3RSNRU8LQJclHrgNx_XURFBUqVTc-__J1aOXp4m7yaeUEMwdCq0XtQGjRffv2Tsq72ZDw78qBU9fdkrwb-OlmnezWj7gODFsnPldMCqXcvm9_jEKFkOBvxonYq5N9cY2-U9uvAHBn0_vJv-fZzV-3d7Ns_Z_HuRPMlrSiSA1pD2S3X1bryd1d9ricL26_9YoMzr1tgcOqaTZ9uH-8vZsv2xWtIhc-Fbmw8Nu3dy3tP0N4yWD1n9V6fp99mdwbvXqTvGaDnvhx-TCdr1YPA4mDFaPRxRPaGbePrGAEXBe4_3Sf1vCtFLir7V5fd4ghozfcArUe_gsu0Wajj3eH-ZfJzd08mz1MjX8_LBYvOfUk6_lqPZusJy_IThQPD3dvcZl_m9w_3s1fkrmz6cOXxe2nbPLVzz7ffvp8c7uezR_XJtx7F9TriP-e39xntw9nNMfp5V9f1rf382z6-Fc2m6_n0_VLyv8_D__L83BWw7Xl0XkldTgCC4yBE3qHSgNckeuApEGKrui1H6VeAv3U86421yGMc1L4KESUpn6UED8ICi-PkecVEHveFbuGHgy8OPD9KBx73ihGOI_jPIqjPIFROHZCj9aIVSNTy4yELK_aj8auoxDGyVWFclqpw-d-8rotePKmVE7otWn7tEwzXdFrB8Kzb-He-u4NQrDfUD4oSNuvA53Ie_GplRN5QPDD51_d1l81srr-_Q_jWjX_LwAA__9kSv1b">