forked from OSchip/llvm-project
7bc9185ab5
The motivation is to recognize code such as this from /llvm/projects/test-suite/SingleSource/Benchmarks/BenchmarkGame/n-body.c: float distance = sqrt(dx * dx + dy * dy + dz * dz); float mag = dt / (distance * distance * distance); Without this patch, we don't match the sqrt as a reciprocal sqrt, so for PPC the new testcase in this patch produces: addis 3, 2, .LCPI4_2@toc@ha lfs 4, .LCPI4_2@toc@l(3) addis 3, 2, .LCPI4_1@toc@ha lfs 0, .LCPI4_1@toc@l(3) fcmpu 0, 1, 4 beq 0, .LBB4_2 # BB#1: frsqrtes 4, 1 addis 3, 2, .LCPI4_0@toc@ha lfs 5, .LCPI4_0@toc@l(3) fnmsubs 13, 1, 5, 1 fmuls 6, 4, 4 fmadds 1, 13, 6, 5 fmuls 1, 4, 1 fres 4, 1 <--- reciprocal of reciprocal square root fnmsubs 1, 1, 4, 0 fmadds 4, 4, 1, 4 .LBB4_2: fmuls 1, 4, 2 fres 2, 1 fnmsubs 0, 1, 2, 0 fmadds 0, 2, 0, 2 fmuls 1, 3, 0 blr After the patch, this simplifies to: frsqrtes 0, 1 addis 3, 2, .LCPI4_1@toc@ha fres 5, 2 lfs 4, .LCPI4_1@toc@l(3) addis 3, 2, .LCPI4_0@toc@ha lfs 7, .LCPI4_0@toc@l(3) fnmsubs 13, 1, 4, 1 fmuls 6, 0, 0 fnmsubs 2, 2, 5, 7 fmadds 1, 13, 6, 4 fmadds 2, 5, 2, 5 fmuls 0, 0, 1 fmuls 0, 0, 2 fmuls 1, 3, 0 blr Differential Revision: http://reviews.llvm.org/D5628 llvm-svn: 219139 |
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| cmake | ||
| docs | ||
| examples | ||
| include | ||
| lib | ||
| projects | ||
| test | ||
| tools | ||
| unittests | ||
| utils | ||
| .arcconfig | ||
| .clang-format | ||
| .clang-tidy | ||
| .gitignore | ||
| CMakeLists.txt | ||
| CODE_OWNERS.TXT | ||
| CREDITS.TXT | ||
| LICENSE.TXT | ||
| LLVMBuild.txt | ||
| Makefile | ||
| Makefile.common | ||
| Makefile.config.in | ||
| Makefile.rules | ||
| README.txt | ||
| configure | ||
| llvm.spec.in | ||
README.txt
Low Level Virtual Machine (LLVM) ================================ This directory and its subdirectories contain source code for the Low Level Virtual Machine, 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're writing a package for LLVM, see docs/Packaging.rst for our suggestions.