[PATCH] D115302: GlobalsModRef should treat functions w/o nosync conservatively.

Wed Dec 8 15:07:47 PST 2021

tra added a comment.

In D115302#3181180 <https://reviews.llvm.org/D115302#3181180>, @jdoerfert wrote:

> EDIT:
> Second thought, this does not fix my bug: https://lists.llvm.org/pipermail/llvm-dev/2021-December/154185.html

I think it may. At least it does seem to preserve the load and produces identical code for both functions in my build. Unpatched clang does not.

  Args: bin/opt -debug -aa-pipeline=basic-aa,globals-aa -passes=require<globals-aa>,function(gvn<pre;load-pre;split-backedge-load-pre;memdep>) -S
  GVN iteration: 0
  GVN: load i32 %r is clobbered by   call void @llvm.sync()
  GVN iteration: 0
  GVN: load i32 %r is clobbered by   call void @sync()

Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D115302/new/

https://reviews.llvm.org/D115302