llvm/lib/LTO
Richard Smith 63ec2563a9 Add a flag to remap manglings when reading profile data information.
This can be used to preserve profiling information across codebase
changes that have widespread impact on mangled names, but across which
most profiling data should still be usable. For example, when switching
from libstdc++ to libc++, or from the old libstdc++ ABI to the new ABI,
or even from a 32-bit to a 64-bit build.

The user can provide a remapping file specifying parts of mangled names
that should be treated as equivalent (eg, std::__1 should be treated as
equivalent to std::__cxx11), and profile data will be treated as
applying to a particular function if its name is equivalent to the name
of a function in the profile data under the provided equivalences. See
the documentation change for a description of how this is configured.

Remapping is supported for both sample-based profiling and instruction
profiling. We do not support remapping indirect branch target
information, but all other profile data should be remapped
appropriately.

Support is only added for the new pass manager. If someone wants to also
add support for this for the old pass manager, doing so should be
straightforward.

This is the LLVM side of Clang r344199.

Reviewers: davidxl, tejohnson, dlj, erik.pilkington

Subscribers: mehdi_amini, steven_wu, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D51249

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344200 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-10 23:13:47 +00:00
..
Caching.cpp [ThinLTO] Update ThinLTO cache file atimes when on Windows 2018-07-04 14:17:10 +00:00
CMakeLists.txt Support: Add a VCSRevision.h header file. 2017-04-13 01:26:12 +00:00
LLVMBuild.txt NFC: Move ObjectMemoryBuffer to support 2018-04-15 05:17:14 +00:00
LTO.cpp Add a flag to remap manglings when reading profile data information. 2018-10-10 23:13:47 +00:00
LTOBackend.cpp Add a flag to remap manglings when reading profile data information. 2018-10-10 23:13:47 +00:00
LTOCodeGenerator.cpp [PassTiming] cleaning up legacy PassTimingInfo interface. NFCI. 2018-09-26 13:01:43 +00:00
LTOModule.cpp Move TargetLoweringObjectFile from CodeGen to Target to fix layering 2018-03-23 23:58:19 +00:00
ThinLTOCodeGenerator.cpp llvm::sort(C.begin(), C.end(), ...) -> llvm::sort(C, ...) 2018-09-27 02:13:45 +00:00
UpdateCompilerUsed.cpp [LTO] Account for overriding lib calls via the alias attribute 2018-10-10 22:54:31 +00:00