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Old fork of llvm-mirror, used on older RPCS3 builds
4c3428b604
Summary: Avoids tons of prologue boilerplate when arguments are passed in memory and left in memory. This can happen in a debug build or in a release build when an argument alloca is escaped. This will dramatically affect the code size of x86 debug builds, because X86 fast isel doesn't handle arguments passed in memory at all. It only handles the x86_64 case of up to 6 basic register parameters. This is implemented by analyzing the entry block before ISel to identify copy elision candidates. A copy elision candidate is an argument that is used to fully initialize an alloca before any other possibly escaping uses of that alloca. If an argument is a copy elision candidate, we set a flag on the InputArg. If the the target generates loads from a fixed stack object that matches the size and alignment requirements of the alloca, the SelectionDAG builder will delete the stack object created for the alloca and replace it with the fixed stack object. The load is left behind to satisfy any remaining uses of the argument value. The store is now dead and is therefore elided. The fixed stack object is also marked as mutable, as it may now be modified by the user, and it would be invalid to rematerialize the initial load from it. Supersedes D28388 Fixes PR26328 Reviewers: chandlerc, MatzeB, qcolombet, inglorion, hans Subscribers: igorb, llvm-commits Differential Revision: https://reviews.llvm.org/D29668 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296683 91177308-0d34-0410-b5e6-96231b3b80d8 |
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| docs | ||
| examples | ||
| include | ||
| lib | ||
| projects | ||
| resources | ||
| runtimes | ||
| test | ||
| tools | ||
| unittests | ||
| utils | ||
| .arcconfig | ||
| .clang-format | ||
| .clang-tidy | ||
| .gitignore | ||
| CMakeLists.txt | ||
| CODE_OWNERS.TXT | ||
| configure | ||
| CREDITS.TXT | ||
| LICENSE.TXT | ||
| llvm.spec.in | ||
| LLVMBuild.txt | ||
| README.txt | ||
| RELEASE_TESTERS.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 are writing a package for LLVM, see docs/Packaging.rst for our suggestions.