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| author | Eli Friedman <eli.friedman@gmail.com> | 2011-03-18 02:34:11 +0000 |
|---|---|---|
| committer | Eli Friedman <eli.friedman@gmail.com> | 2011-03-18 02:34:11 +0000 |
| commit | 1a916a3c0cde22c734f3d7c38c6b1da2cc5f6a06 (patch) | |
| tree | 5d397778e9f6a6b96f284263fee39d4b46146788 /clang/lib/Frontend/CompilerInvocation.cpp | |
| parent | 4422bfea50d1ef2256bd6a996bbe83793d45e0c1 (diff) | |
| download | bcm5719-llvm-1a916a3c0cde22c734f3d7c38c6b1da2cc5f6a06.tar.gz bcm5719-llvm-1a916a3c0cde22c734f3d7c38c6b1da2cc5f6a06.zip | |
Add a target-specific branchless method for double-width relational
comparisons on x86. Essentially, the way this works is that SUB+SBB sets
the relevant flags the same way a double-width CMP would.
This is a substantial improvement over the generic lowering in LLVM. The output
is also shorter than the gcc-generated output; I haven't done any detailed
benchmarking, though.
llvm-svn: 127852
Diffstat (limited to 'clang/lib/Frontend/CompilerInvocation.cpp')
0 files changed, 0 insertions, 0 deletions
