[all-commits] [llvm/llvm-project] b361d3: [MergeFuncs] Remove incorrect attribute copying

[Nikita Popov via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: b361d3bbcd85647c9f6640a5f57932c43fdb7a1a
      https://github.com/llvm/llvm-project/commit/b361d3bbcd85647c9f6640a5f57932c43fdb7a1a
  Author: Nikita Popov <nikita.ppv at gmail.com>
  Date:   2019-12-11 (Wed, 11 Dec 2019)

  Changed paths:
    M llvm/lib/Transforms/IPO/MergeFunctions.cpp
    A llvm/test/Transforms/MergeFunc/byval-attr-congruent-type.ll

  Log Message:
  -----------
  [MergeFuncs] Remove incorrect attribute copying

Fix for https://bugs.llvm.org/show_bug.cgi?id=44236. This code was
originally introduced in rG36512330041201e10f5429361bbd79b1afac1ea1.
However, the attribute copying was done in the wrong place (in general
call replacement, not thunk generation) and a proper fix was
implemented in D12581.

Previously this code was just unnecessary but harmless (because
FunctionComparator ensured that the attributes of the two functions
are exactly the same), but since byval was changed to accept a type
this copying is actively wrong and may result in malformed IR.

Differential Revision: https://reviews.llvm.org/D71173