[all-commits] [llvm/llvm-project] 456497: [SCCP] Propagate inequalities

[Nikita Popov via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 456497450482153afe86838ac2e2be395206d377
      https://github.com/llvm/llvm-project/commit/456497450482153afe86838ac2e2be395206d377
  Author: Nikita Popov <nikita.ppv at gmail.com>
  Date:   2020-08-04 (Tue, 04 Aug 2020)

  Changed paths:
    M llvm/include/llvm/Analysis/ValueLattice.h
    M llvm/lib/Transforms/Scalar/SCCP.cpp
    M llvm/test/Transforms/SCCP/assume.ll
    M llvm/test/Transforms/SCCP/metadata.ll

  Log Message:
  -----------
  [SCCP] Propagate inequalities

Teach SCCP to create notconstant lattice values from inequality
assumes and nonnull metadata, and update getConstant() to make
use of them. Additionally isOverdefined() needs to be changed to
consider notconstant an overdefined value.

Handling inequality branches is delayed until our branch on undef
story in other passes has been improved.

Differential Revision: https://reviews.llvm.org/D83643