[all-commits] [llvm/llvm-project] d41f6c: [CodeGen] Skip null physical register in AntiDepBr...

[Sergei Barannikov via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: d41f6cff030369d99ad62bbdba732552c08d48a6
      https://github.com/llvm/llvm-project/commit/d41f6cff030369d99ad62bbdba732552c08d48a6
  Author: Sergei Barannikov <barannikov88 at gmail.com>
  Date:   2023-05-24 (Wed, 24 May 2023)

  Changed paths:
    M llvm/lib/CodeGen/AggressiveAntiDepBreaker.cpp
    M llvm/lib/CodeGen/CriticalAntiDepBreaker.cpp

  Log Message:
  -----------
  [CodeGen] Skip null physical register in AntiDepBreaker (NFCI)

D151036 adds an assertions that prohibits iterating over sub- and
super-registers of a null register. This is already the case when
iterating over register units of a null register, and worked by
accident for sub- and super-registers.
The only place where the assertion is currently triggering is in
CriticalAntiDepBreaker::ScanInstruction. Other places are changed
in case new assertions are added and should be harmless otherwise.

Differential Revision: https://reviews.llvm.org/D151288