This patch adds support to the WholeProgramDevirt pass to perform
index-based WPD, which is invoked from ThinLTO during the thin link.
The ThinLTO backend (WPD import phase) behaves the same regardless of
whether the WPD decisions were made with the index-based or (the
existing) IR-based analysis.
Depends on D54815.
Reviewers: pcc
Subscribers: mehdi_amini, inglorion, eraman, steven_wu, dexonsmith, arphaman, dang, llvm-commits
Differential Revision: https://reviews.llvm.org/D55153
llvm-svn: 367679
Reenable the testing disabled in r364978 with the same workaround used
for this failure in the cfi-devirt.ll test. The known issue is PR39436,
and the workaround is to add -verify-machineinstrs=0.
llvm-svn: 364997
When adding summary entries for index-based WPD (r364960), an added
test also included some additional testing of the existing hybrid
Thin/Regular LTO WPD (test/ThinLTO/X86/devirt.ll). That part of the
test is producing a failure on the llvm-clang-x86_64-expensive-checks-win
bot:
*** Bad machine code: Explicit definition marked as use ***
- function: __typeid__ZTS1A_0_branch_funnel
- basic block: %bb.0 (0x81d4c58)
- instruction: ICALL_BRANCH_FUNNEL %0:gr64, @0, 16, @_ZN1B1fEi, 48, @_ZN1C1fEi
- operand 0: %0:gr64
LLVM ERROR: Found 1 machine code errors.
This is functionality unrelated to the summary entries added with my
patch, so I am disabling this part of the new test until it is
addressed. I'll continue to investigate the failure.
llvm-svn: 364978
Summary:
If LTOUnit splitting is disabled, the module summary analysis computes
the summary information necessary to perform single implementation
devirtualization during the thin link with the index and no IR. The
information collected from the regular LTO IR in the current hybrid WPD
algorithm is summarized, including:
1) For vtable definitions, record the function pointers and their offset
within the vtable initializer (subsumes the information collected from
IR by tryFindVirtualCallTargets).
2) A record for each type metadata summarizing the vtable definitions
decorated with that metadata (subsumes the TypeIdentiferMap collected
from IR).
Also added are the necessary bitcode records, and the corresponding
assembly support.
The follow-on index-based WPD patch is D55153.
Depends on D53890.
Reviewers: pcc
Subscribers: mehdi_amini, Prazek, inglorion, eraman, steven_wu, dexonsmith, arphaman, llvm-commits
Differential Revision: https://reviews.llvm.org/D54815
llvm-svn: 364960
Summary:
If LTOUnit splitting is disabled, the module summary analysis computes
the summary information necessary to perform single implementation
devirtualization during the thin link with the index and no IR. The
information collected from the regular LTO IR in the current hybrid WPD
algorithm is summarized, including:
1) For vtable definitions, record the function pointers and their offset
within the vtable initializer (subsumes the information collected from
IR by tryFindVirtualCallTargets).
2) A record for each type metadata summarizing the vtable definitions
decorated with that metadata (subsumes the TypeIdentiferMap collected
from IR).
Also added are the necessary bitcode records, and the corresponding
assembly support.
The index-based WPD will be sent as a follow-on.
Depends on D53890.
Reviewers: pcc
Subscribers: mehdi_amini, Prazek, inglorion, eraman, steven_wu, dexonsmith, arphaman, llvm-commits
Differential Revision: https://reviews.llvm.org/D54815
llvm-svn: 351453
