[all-commits] [llvm/llvm-project] bfa7f6: [Assignment Tracking][20/*] Account for assignment...

[Orlando Cazalet-Hyams via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: bfa7f6241251589b0c8ba8d203347cf63a8dc298
      https://github.com/llvm/llvm-project/commit/bfa7f6241251589b0c8ba8d203347cf63a8dc298
  Author: OCHyams <orlando.hyams at sony.com>
  Date:   2022-11-15 (Tue, 15 Nov 2022)

  Changed paths:
    M llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
    A llvm/test/DebugInfo/Generic/assignment-tracking/dse/dse-after-memcpyopt-merge.ll
    A llvm/test/DebugInfo/Generic/assignment-tracking/dse/shorten.ll

  Log Message:
  -----------
  [Assignment Tracking][20/*] Account for assignment tracking in DSE

The Assignment Tracking debug-info feature is outlined in this RFC:

https://discourse.llvm.org/t/
rfc-assignment-tracking-a-better-way-of-specifying-variable-locations-in-ir

DeadStoreElimmination shortens stores that are shadowed by later stores such
that the overlapping part of the earlier store is omitted. Insert an unlinked
dbg.assign intrinsic with a variable fragment that describes the omitted part
to signal that that fragment of the variable has a stale value in memory.

Reviewed By: jmorse

Differential Revision: https://reviews.llvm.org/D133315