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| author | Tim Northover <tnorthover@apple.com> | 2014-04-16 11:52:51 +0000 |
|---|---|---|
| committer | Tim Northover <tnorthover@apple.com> | 2014-04-16 11:52:51 +0000 |
| commit | 18f68f6d1a21ed26d4c80e344b7b4a5d20b49ac5 (patch) | |
| tree | 2805dac35609a3d7cd4a8deab514bb4b40412f86 /llvm/lib/MC/MCObjectFileInfo.cpp | |
| parent | 9cfb57dafa783812109ccf94fe47a462732809d8 (diff) | |
| download | bcm5719-llvm-18f68f6d1a21ed26d4c80e344b7b4a5d20b49ac5.tar.gz bcm5719-llvm-18f68f6d1a21ed26d4c80e344b7b4a5d20b49ac5.zip | |
ARM64: use 32-bit moves for constants where possible.
If we know that a particular 64-bit constant has all high bits zero, then we
can rely on the fact that 32-bit ARM64 instructions automatically zero out the
high bits of an x-register. This gives the expansion logic less constraints to
satisfy and so sometimes allows it to pick better sequences.
Came up while porting test/CodeGen/AArch64/movw-consts.ll: this will allow a
32-bit MOVN to be used in @test8 soon.
llvm-svn: 206379
Diffstat (limited to 'llvm/lib/MC/MCObjectFileInfo.cpp')
0 files changed, 0 insertions, 0 deletions
