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| author | Craig Topper <craig.topper@intel.com> | 2019-10-13 06:48:05 +0000 |
|---|---|---|
| committer | Craig Topper <craig.topper@intel.com> | 2019-10-13 06:48:05 +0000 |
| commit | d50cb9ac8ca1ea266751c42b8f6c74fa82a0944a (patch) | |
| tree | be5c7c68d0d3d698541d3092841d45c2d59368e9 /lldb/packages/Python/lldbsuite/test/python_api/thread/main.cpp | |
| parent | bf57aa2b25c54a30246cd87addfdb90529908fd3 (diff) | |
| download | bcm5719-llvm-d50cb9ac8ca1ea266751c42b8f6c74fa82a0944a.tar.gz bcm5719-llvm-d50cb9ac8ca1ea266751c42b8f6c74fa82a0944a.zip | |
[X86] Add a one use check on the setcc to the min/max canonicalization code in combineSelect.
This seems to improve std::midpoint code where we have a min and
a max with the same condition. If we split the setcc we can end
up with two compares if the one of the operands is a constant.
Since we aggressively canonicalize compares with constants.
For non-constants it can interfere with our ability to share
control flow if we need to expand cmovs into control flow.
I'm also not sure I understand this min/max canonicalization code.
The motivating case talks about comparing with 0. But we don't
check for 0 explicitly.
Removes one instruction from the codegen for PR43658.
llvm-svn: 374706
Diffstat (limited to 'lldb/packages/Python/lldbsuite/test/python_api/thread/main.cpp')
0 files changed, 0 insertions, 0 deletions
