[llvm-commits] [llvm] r60399 - in /llvm/trunk/lib: Target/README.txt Transforms/Scalar/InstructionCombining.cpp

[Duncan Sands]

Hi,

> - Remove the buggy -X/C -> X/-C transform. This isn't valid when X isn't a
>   constant. If X is a constant, then this is folded elsewhere.

why isn't this valid if X isn't a constant?  It is only invalid if
X == minint as far as I can see (of course, it may be hard to tell
if X == minint if X is not a constant).  Even if you restrict X to
being a constant for simplicity, C doesn't need to be a constant
(you don't need to check anything about C).

Ciao,

Duncan.