forked from OSchip/llvm-project
90c31b0f42
ISD::FROUND is defined to round to nearest with ties rounding away from 0. This mode isn't supported in hardware on X86. But as long as we aren't compiling with trapping math, we can emulate this with floor(X + copysign(nextafter(0.5, 0.0), X)). We have to use nextafter to avoid some corner cases that adding 0.5 would have. For example, if X is nextafter(0.5, 0.0) it should round to 0.0, but adding 0.5 would need one extra bit of mantissa than can be stored so it rounds to 1.0. Adding nextafter(0.5, 0.0) instead will just increase the exponent by 1 and leave the mantissa as all 1s. This would be nextafter(1.0, 0.0) which will floor to 0.0. Techically this requires -fno-trapping-math which isn't our default. But if we care about exceptions we should be using constrained intrinsics. Constrained intrinsics would use STRICT_FROUND which won't go through this code. Fixes PR42195. Differential Revision: https://reviews.llvm.org/D73607 |
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| include | ||
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| runtimes | ||
| test | ||
| tools | ||
| unittests | ||
| utils | ||
| .arcconfig | ||
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| .gitattributes | ||
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| CMakeLists.txt | ||
| CODE_OWNERS.TXT | ||
| CREDITS.TXT | ||
| LICENSE.TXT | ||
| LLVMBuild.txt | ||
| README.txt | ||
| RELEASE_TESTERS.TXT | ||
| configure | ||
| llvm.spec.in | ||
README.txt
The LLVM Compiler Infrastructure ================================ This directory and its subdirectories contain source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and runtime environments. LLVM is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt. Please see the documentation provided in docs/ for further assistance with LLVM, and in particular docs/GettingStarted.rst for getting started with LLVM and docs/README.txt for an overview of LLVM's documentation setup. If you are writing a package for LLVM, see docs/Packaging.rst for our suggestions.