[llvm-commits] [PATCH] AndOrXor Chain Optimization

[Daniel Nicácio]

Hi, this patch increments the instcombiner pass.
It adds a new XOR, OR, AND optimization, trying to find a chain of logical
instructions (xor, and, or) operating on different bits of the same word. If
this chain is found, it is collapsed into a single logical instruction.
The figure below shows a generic example:

[image: XORChain.png]

Any comments and critics are welcome.

Thanks,

Daniel Nicacio
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