forked from OSchip/llvm-project
f740129198
MIPS32 has instructions for efficient count-leading/trailing-zeros, so this should be considered a cheap operation (and therefore fair game for speculation) for any MIPS32 implementation. The net result of allowing this speculation for the regression tests in this patch is that we get this code: ctlz: jr $ra clz $2, $4 cttz: addiu $1, $4, -1 not $2, $4 and $1, $2, $1 clz $1, $1 addiu $2, $zero, 32 jr $ra subu $2, $2, $1 Instead of: ctlz: beqz $4, $BB0_2 addiu $2, $zero, 32 clz $2, $4 $BB0_2: jr $ra nop cttz: beqz $4, $BB1_2 addiu $2, $zero, 32 addiu $1, $4, -1 not $2, $4 and $1, $2, $1 clz $1, $1 addiu $2, $zero, 32 subu $2, $2, $1 $BB1_2: jr $ra nop See D14469 for the larger motivation. Differential Revision: http://reviews.llvm.org/D14500 llvm-svn: 252755 |
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| docs | ||
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| include | ||
| lib | ||
| projects | ||
| resources | ||
| 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 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're writing a package for LLVM, see docs/Packaging.rst for our suggestions.