[PATCH] D78455: [Scalarizer] Fix a non-deterministic scatter order problem

[Bjorn Pettersson via Phabricator via llvm-commits]

bjope created this revision.
bjope added reviewers: foad, cameron.mcinally, uabelho.
Herald added subscribers: mgrang, hiraditya.
Herald added a project: LLVM.

The indexing operator in Scatterer may result in building new
instructions. When using multiple such operators in a function
argument list the order in which we build instructions depend on
argument evaluation order (which is undefined in C++).
This patch avoid such problems by expanding the components using
the [] operator prior to the function call.

Problem was seen when comparing output, while builing LLVM with
different compilers (clang vs gcc).


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D78455

Files:
  llvm/lib/Transforms/Scalar/Scalarizer.cpp
  llvm/test/Transforms/Scalarizer/scatter-order.ll

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