mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-12-14 15:19:33 +00:00
Fork of llvm with experimental commits and workarounds for RPCS3
a496d0518f
This allows a call site tag in CU A to reference a callee DIE in CU B without resorting to creating an incomplete duplicate DIE for the callee inside of CU A. We already allow cross-CU references of subprogram declarations, so it doesn't seem like definitions ought to be special. This improves entry value evaluation and tail call frame synthesis in the LTO setting. During LTO, it's common for cross-module inlining to produce a call in some CU A where the callee resides in a different CU, and there is no declaration subprogram for the callee anywhere. In this case llvm would (unnecessarily, I think) emit an empty DW_TAG_subprogram in order to fill in the call site tag. That empty 'definition' defeats entry value evaluation etc., because the debugger can't figure out what it means. As a follow-up, maybe we could add a DWARF verifier check that a DW_TAG_subprogram at least has a DW_AT_name attribute. Update: Reland with a fix to create a declaration DIE when the declaration is missing from the CU's retainedTypes list. The declaration is left out of the retainedTypes list in two cases: 1) Re-compiling pre-r266445 bitcode (in which declarations weren't added to the retainedTypes list), and 2) Doing LTO function importing (which doesn't update the retainedTypes list). It's possible to handle (1) and (2) by modifying the retainedTypes list (in AutoUpgrade, or in the LTO importing logic resp.), but I don't see an advantage to doing it this way, as it would cause more DWARF to be emitted compared to creating the declaration DIEs lazily. Tested with a stage2 ThinLTO+RelWithDebInfo build of clang, and with a ReleaseLTO-g build of the test suite. rdar://46577651, rdar://57855316, rdar://57840415 Differential Revision: https://reviews.llvm.org/D70350 |
||
|---|---|---|
| benchmarks | ||
| bindings | ||
| cmake | ||
| docs | ||
| examples | ||
| include | ||
| lib | ||
| projects | ||
| resources | ||
| runtimes | ||
| test | ||
| tools | ||
| unittests | ||
| utils | ||
| .arcconfig | ||
| .clang-format | ||
| .clang-tidy | ||
| .gitattributes | ||
| .gitignore | ||
| CMakeLists.txt | ||
| CODE_OWNERS.TXT | ||
| configure | ||
| CREDITS.TXT | ||
| LICENSE.TXT | ||
| llvm.spec.in | ||
| LLVMBuild.txt | ||
| README.txt | ||
| RELEASE_TESTERS.TXT | ||
The LLVM Compiler Infrastructure ================================ This directory and its subdirectories contain source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and runtime environments. LLVM is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt. Please see the documentation provided in docs/ for further assistance with LLVM, and in particular docs/GettingStarted.rst for getting started with LLVM and docs/README.txt for an overview of LLVM's documentation setup. If you are writing a package for LLVM, see docs/Packaging.rst for our suggestions.