tree cc5c39072cfe6815fb233e0f048b0c9c7f299b10
parent 4ef35aa14f4bdd041bcf4184b8bbc3c27467557b
author Dean Michael Berris <dberris@google.com> 1536890352 +0000
committer Dean Michael Berris <dberris@google.com> 1536890352 +0000

[XRay][clang] Emit "never-instrument" attribute

Summary:
Before this change, we only emit the XRay attributes in LLVM IR when the
-fxray-instrument flag is provided. This may cause issues with thinlto
when the final binary is being built/linked with -fxray-instrument, and
the constitutent LLVM IR gets re-lowered with xray instrumentation.

With this change, we can honour the "never-instrument "attributes
provided in the source code and preserve those in the IR. This way, even
in thinlto builds, we retain the attributes which say whether functions
should never be XRay instrumented.

This change addresses llvm.org/PR38922.

Reviewers: mboerger, eizan

Subscribers: mehdi_amini, dexonsmith, cfe-commits, llvm-commits

Differential Revision: https://reviews.llvm.org/D52015

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@342200 91177308-0d34-0410-b5e6-96231b3b80d8