[all-commits] [llvm/llvm-project] 4036a0: [InstCombine] enhance freelyNegateValue() by handl...

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  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 4036a0af240e457fd4db62e213dbd958821b1788
      https://github.com/llvm/llvm-project/commit/4036a0af240e457fd4db62e213dbd958821b1788
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2020-04-05 (Sun, 05 Apr 2020)

  Changed paths:
    M llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
    M llvm/test/Transforms/InstCombine/sub-of-negatible.ll

  Log Message:
  -----------
  [InstCombine] enhance freelyNegateValue() by handling 'not'

This patch extends D77230. If we have a 'not' instruction inside a
negated expression, we can ignore extra uses of that op because the
negation has a one-to-one replacement: negate becomes increment.

Alive2 examples of the test cases:
http://volta.cs.utah.edu:8080/z/T5-u9P
http://volta.cs.utah.edu:8080/z/eT89L6

Differential Revision: https://reviews.llvm.org/D77459