Merge ObjWriter into dotnet/main and update to LLVM 14 API #287
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* Taken from https://github.com/dotnet/runtime/tree/7ab969c84ef05ba948c0075392716ce335b47744/src/coreclr/tools/aot/ObjWriter. * Updated README.md * Updated CMakeLists.txt to remove reference to CORECLR_INCLUDE_DIR. * Added cordebuginfo.h, cvconst.h, cfi.h from coreclr/inc at the above commit.
Do this unconditionally because there's no scenario where we would need executable stack for managed code.
This caught my attention as I was looking at the ObjWriter. LLVM no longer emits a `LC_VERSION_MIN_MACOSX` load command unless we explicitly set a version. I don't see a difference in `llvm-objdump -macho -x foo.o` with/without these lines (I didn't bother myself to boot into macOS to run `otool`).
Fixes https://github.com/dotnet/runtimelab/issues/1535. No warnings left with llvm-dwarfdump from LLVM 12.
This reverts commit afc9070.
…s `FileCheck` and `llvm-mca` (dotnet#256) https://github.com/dotnet/runtime is wanting to start writing assembly (x64/ARM64) verification tests. Instead of building our own tool to support writing those kinds of tests, we want to leverage LLVM's `FileCheck`. We also want to include `llvm-mca` at the request of @EgorBo This PR creates a new NuGet package for `dotnet/runtime` to consume which we named `Microsoft.NETCore.Runtime.JIT.Tools`. So far, this package only includes LLVM's `FileCheck` and `llvm-mca` tools.
…if not explicitly overridden
We support `.bss` but not custom sections that are bss-like. This adds such support.
If we ended up with nothing in the text section, this line would error LLVM out in: https://github.com/dotnet/llvm-project/blob/3db8d68195c17386557f1a258312bbae4051dc05/llvm/lib/MC/ELFObjectWriter.cpp#L1458-L1459 Because we generate a reference to the empty text section in the `aranges` section. I double checked and debugging on Linux still works fine without this. `SetCodeSectionAttribute` is an objwriter API and we have access to it from the managed side. We should be calling it from there if it's needed for something that I didn't realize (we do call it from the managed side for the `.managed` section, but that one actually has debug information generated, unlike `.text`).
The DWARF specification states that the form of an exprloc consists of an unsigned LEB128 length value, followed by the encoded location bytes of the specified length. For some reason we were adding one to the length value being emitted. This looks incorrect to me. The above calculation for REG-REG (a variable stored in two registers) correctly calculates the length of each register type tag, plus the size of the interpolating PIECE tags, plus the size of notation for each register. The extra byte looks wrong. I've tested this locally and it appears to resolve dotnet/runtime#77407. Unfortunately, it also causes llvm-dwarfdump --verify to constantly complain about missing base addresses. I can't confirm at the moment, but my suspicion is that this is revealing an existing bug. Even if this is somehow causing a new bug, I think the resulting symbols with this change are better than the alternative (no working symbols at all).
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Hi @filipnavara, first of all thanks for your contributions 😁, I am following up this PR because I want to measure how much effort would it take to upgrade llvm's version |
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The effort should not be that big. Not sure if I applied all the recent patches from ObjWriter branch. Fixing the build breaks would likely be relatively easy too (at least by switching to different build machine images). I am more than happy to revive this PR if there's interest. |
In order to understand what is happening with std path error.
This reverts commit 5c4636e.
@filipnavara Do you mean upgrading linux build image version in the yaml file? I am not able to reproduce locally the error the pipeline is getting |
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Thanks for fixing the compiler references. Now we are back to an error that was occurring previously: I'll try to reproduce and fix it locally. |
BrianBohe
reviewed
Feb 3, 2023
BrianBohe
reviewed
Feb 3, 2023
$(ClangVersion) $(ClangPlusVersion) weren't defined for OSX and should be defined for every Linux
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Thanks @filipnavara! Nice work! |
BrianBohe
approved these changes
Feb 3, 2023
akoeplinger
reviewed
Feb 4, 2023
Always quote _BuildConfig on command line so empty value is not accidentally using next parameter as the value
…ted as environment variable into wrong steps
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@filipnavara Thanks for the contribution! |
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Happy to help! |
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