Update CmpResult to use a pointer-sized return type
#920
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tgross35
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As seen at [1], LLVM uses `long long` on LLP64 (to get a 64-bit integer matching pointer size) and `long` on everything else, with exceptions for AArch64 and AVR. Our current logic always uses an `i32`. This happens to work because LLVM uses 32-bit instructions to check the output on x86-64, but the GCC checks the full 64-bit register so garbage in the upper half leads to incorrect results. Update our return type to be `isize`, with exceptions for AArch64 and AVR. Fixes: rust-lang#919 [1]: https://github.com/llvm/llvm-project/blob/0cf3c437c18ed27d9663d87804a9a15ff6874af2/compiler-rt/lib/builtins/fp_compare_impl.inc#L11-L27
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Could you please make a release with this fix? |
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I was hoping rust-lang/rust#141229 would be merged by now :) but since it isn't, I'll get the release+bump going. |
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Includes the following changes: * Enable `__powitf2` on MSVC [1] * Update `CmpResult` to use a pointer-sized return type [2] * Better code reuse between `libm` and `compiler-builtins` [3], [4] * Stop building C versions of `__netf2` [5] since we have our own implementation [1]: rust-lang/compiler-builtins#918 [2]: rust-lang/compiler-builtins#920 [3]: rust-lang/compiler-builtins#879 [4]: rust-lang/compiler-builtins#925 [5]: rust-lang/compiler-builtins#828
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Update `compiler-builtins` to 0.1.160 Includes the following changes: * Enable `__powitf2` on MSVC [1] * Update `CmpResult` to use a pointer-sized return type [2] * Better code reuse between `libm` and `compiler-builtins` [3], [4] * Stop building C versions of `__netf2` [5] since we have our own implementation [1]: rust-lang/compiler-builtins#918 [2]: rust-lang/compiler-builtins#920 [3]: rust-lang/compiler-builtins#879 [4]: rust-lang/compiler-builtins#925 [5]: rust-lang/compiler-builtins#828
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Rollup merge of #141805 - tgross35:update-builtins, r=tgross35 Update `compiler-builtins` to 0.1.160 Includes the following changes: * Enable `__powitf2` on MSVC [1] * Update `CmpResult` to use a pointer-sized return type [2] * Better code reuse between `libm` and `compiler-builtins` [3], [4] * Stop building C versions of `__netf2` [5] since we have our own implementation [1]: rust-lang/compiler-builtins#918 [2]: rust-lang/compiler-builtins#920 [3]: rust-lang/compiler-builtins#879 [4]: rust-lang/compiler-builtins#925 [5]: rust-lang/compiler-builtins#828
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As seen at 1, LLVM uses
long longon LLP64 (to get a 64-bit integer matching pointer size) andlongon everything else, with exceptions for AArch64 and AVR. Our current logic always uses ani32. This happens to work because LLVM uses 32-bit instructions to check the output on x86-64, but the GCC checks the full 64-bit register so garbage in the upper half leads to incorrect results.Update our return type to be
isize, with exceptions for AArch64 and AVR.Fixes: #919