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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82442 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2009-09-21 06:04:07 +00:00
parent 003de66227
commit faa6adf67c

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@ -220,7 +220,20 @@ so cool to turn it into something like:
... which would only do one 32-bit XOR per loop iteration instead of two.
It would also be nice to recognize the reg->size doesn't alias reg->node[i], but
alas...
alas.
//===---------------------------------------------------------------------===//
This should be optimized to one 'and' and one 'or', from PR4216:
define i32 @test_bitfield(i32 %bf.prev.low) nounwind ssp {
entry:
%bf.prev.lo.cleared10 = or i32 %bf.prev.low, 32962 ; <i32> [#uses=1]
%0 = and i32 %bf.prev.low, -65536 ; <i32> [#uses=1]
%1 = and i32 %bf.prev.lo.cleared10, 40186 ; <i32> [#uses=1]
%2 = or i32 %1, %0 ; <i32> [#uses=1]
ret i32 %2
}
//===---------------------------------------------------------------------===//