[llvm-commits] [llvm] r169182 - in /llvm/trunk: lib/Transforms/InstCombine/InstCombine.h lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp test/Transforms/InstCombine/2010-11-01-lshr-mask.ll test/Transforms/InstCombine/shift.ll test/Transforms/InstCombine/signext.ll

[Shuxin Yang]

Yes, we can propagate "exact" to the resulting lshr,
as the resulting lshr shift less bits than the one in the shr+shl 
combination.
I will fix this defect as well.

Thank you for pointing this out.

Shuxin

> If the shift is e.g. "lshr exact i32 %x, 3", can we make the new shift
> "exact" as well?  (See
> http://llvm.org/docs/LangRef.html#lshr-instruction .)
>
> -Eli