forked from OSchip/llvm-project
1b179bc5ff
Summary: LazyValueInfo currently computes the constant value of the switch condition through case edges, which allows the constant value to be propagated through the case edges. But we have seen a case where a zero-extended value of the switch condition is used past case edges for which the constant propagation doesn't occur. This patch adds a small logic to handle such a case in getEdgeValueLocal(). This is motivated by the Python 2.7 eval loop in PyEval_EvalFrameEx() where the lack of the constant propagation causes longer live ranges and more spill code than necessary. With this patch, we see that the code size of PyEval_EvalFrameEx() decreases by ~5.4% and a performance test improves by ~4.6%. Reviewers: wmi, dberlin, sanjoy Reviewed By: sanjoy Subscribers: davide, davidxl, llvm-commits Differential Revision: https://reviews.llvm.org/D34822 llvm-svn: 309415 |
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| clang | ||
| clang-tools-extra | ||
| compiler-rt | ||
| debuginfo-tests | ||
| libclc | ||
| libcxx | ||
| libcxxabi | ||
| libunwind | ||
| lld | ||
| lldb | ||
| llgo | ||
| llvm | ||
| openmp | ||
| parallel-libs | ||
| polly | ||