r355343 was landed and was reverted in r355363 due to build breakage.
This patch adds Linux/Windows support on top of r355343.
In this patch, Darwin should be working with testing case. Linux should be working,
I will enable the testing case in a follwup diff. Windows/Other should be building.
Correct implementation for Other platforms will be added.
Thanks David for reviewing the original diff, helping me with issues on Linux, and
giving suggestions for adding support for Other platforms.
llvm-svn: 355701
Summary:
The llvm-cov tool needs to be able to find coverage names in the
executable, so the .lprfn and .lcovmap sections cannot be merged into
.rdata.
Also, the linker merges .lprfn$M into .lprfn, so llvm-cov needs to
handle that when looking up sections. It has to support running on both
relocatable object files and linked PE files.
Lastly, when loading .lprfn from a PE file, llvm-cov needs to skip the
leading zero byte added by the profile runtime.
Reviewers: vsk
Subscribers: hiraditya, #sanitizers, llvm-commits
Tags: #sanitizers, #llvm
Differential Revision: https://reviews.llvm.org/D58661
llvm-svn: 354840
Summary:
The motivating use case is eliminating duplicate profile data registered
for the same inline function in two object files. Before this change,
users would observe multiple symbol definition errors with VC link, but
links with LLD would succeed.
Users (Mozilla) have reported that PGO works well with clang-cl and LLD,
but when using LLD without this static registration, we would get into a
"relocation against a discarded section" situation. I'm not sure what
happens in that situation, but I suspect that duplicate, unused profile
information was retained. If so, this change will reduce the size of
such binaries with LLD.
Now, Windows uses static registration and is in line with all the other
platforms.
Reviewers: davidxl, wmi, inglorion, void, calixte
Subscribers: mgorny, krytarowski, eraman, fedor.sergeev, hiraditya, #sanitizers, dmajor, llvm-commits
Tags: #sanitizers, #llvm
Differential Revision: https://reviews.llvm.org/D57929
llvm-svn: 353547
Manman Ren