[all-commits] [llvm/llvm-project] 5b25a0: [CVP] Simplify SRem when constantrange abs(lhs) < ...

[luxufan via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 5b25a0bcb14ba0b772a1d6b4ebbed5869a4a0fa7
      https://github.com/llvm/llvm-project/commit/5b25a0bcb14ba0b772a1d6b4ebbed5869a4a0fa7
  Author: luxufan <luxufan at iscas.ac.cn>
  Date:   2023-01-03 (Tue, 03 Jan 2023)

  Changed paths:
    M llvm/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
    M llvm/test/Transforms/CorrelatedValuePropagation/srem.ll

  Log Message:
  -----------
  [CVP] Simplify SRem when constantrange abs(lhs) < abs(rhs)

For `srem x, y`, if abs(constant range of x) less than abs(constant
range of y), we can simplify it as:
`srem x, y => x` if y is guaranteed to be positive.
'srem x, y => -x' if y is guaranteed to be negative.

Differential Revision: https://reviews.llvm.org/D140405