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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - LLDB reads wrong registers on 64bit Windows"
href="https://bugs.llvm.org/show_bug.cgi?id=37485">37485</a>
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<th>Summary</th>
<td>LLDB reads wrong registers on 64bit Windows
</td>
</tr>
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<th>Product</th>
<td>lldb
</td>
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<th>Version</th>
<td>6.0
</td>
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<th>Hardware</th>
<td>PC
</td>
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<th>OS</th>
<td>Windows NT
</td>
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<th>Status</th>
<td>NEW
</td>
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<th>Severity</th>
<td>enhancement
</td>
</tr>
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<th>Priority</th>
<td>P
</td>
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<th>Component</th>
<td>All Bugs
</td>
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<th>Assignee</th>
<td>lldb-dev@lists.llvm.org
</td>
</tr>
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<th>Reporter</th>
<td>kenji.koyanagi@gmail.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr></table>
<p>
<div>
<pre>LLDB reads wrong registers on 64bit Windows because
RegisterContextWindows_x64::GetRegisterInfoAtIndex returns wrong reference.
I encountered broken backtrace when the program stopped at function which does
not have prologue code, such as compiled with '-fomit-frame-pointer'.
In this situation, CFA is equal to rsp but LLDB reads r9.
I investigated the cause.
RegisterContextWindows_x64::GetRegisterInfoAtIndex depends the order of
lldb_XXX_x86_64 values, but RegisterIndex/g_register_infos/g_gpr_reg_indices
does not follow order.
In source/Plugins/Process/Utility/lldb-x86-register-enums.h
The order of GPRs is rax, rbx, rcx, rdx, rdi, rsi, rbp, rsp, r8, ...
In source/Plugins/Process/Windows/Common/x64/RegisterContextWindows_x64.cpp
The order of GPRs is rax, rbx, rcx, rdx, rdi, rsi, r8, r9, r10, ...
I am using is what I built by myself on MinGW.</pre>
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