[all-commits] [llvm/llvm-project] ce0c1f: [DebugInfo] Fix crash when emitting an invalidated...

[Stephen Tozer via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: ce0c1f3ced9bccb29c34b87de82c5cdffcbcd457
      https://github.com/llvm/llvm-project/commit/ce0c1f3ced9bccb29c34b87de82c5cdffcbcd457
  Author: Stephen Tozer <Stephen.Tozer at Sony.com>
  Date:   2021-05-07 (Fri, 07 May 2021)

  Changed paths:
    M llvm/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp
    A llvm/test/DebugInfo/Generic/invalidated-dbg-value-is-undef.ll

  Log Message:
  -----------
  [DebugInfo] Fix crash when emitting an invalidated SDDbgValue

This patch fixes a crash in the compiler that occurs when certain
invalidated SDDbgValues are emitted. The cause of this was that we would
attempt to check the liveness of the debug value's operands, which
triggers an assert if any of those operands are invalid. This patch
changes this check such that it only occurs if the SDDbgValue is valid;
if not, the check is irrelevant anyway, so can be safely ignored.

Differential Revision: https://reviews.llvm.org/D101540