forked from OSchip/llvm-project
bec2a7c4eb
Summary: When Reassociate is rewriting an expression tree it may reuse old binary expression nodes, for new expressions. Whenever an expression node is reused, but with a non-trivial change in the result, we need to invalidate any debug info that is associated with the node. If for example rewriting x = mul a, b y = mul c, x into x = mul c, b y = mul a, x we still get the same result for 'y', but 'x' is a new expression. All debug info referring to 'x' must be invalidated (marked as optimized out) since we no longer calculate the expected value. As a side-effect this patch avoid (at least some) problems where reassociate could end up creating IR with debug-use before def. Earlier the dbg.value nodes where left untouched in the IR, while the reused binary nodes where sinked to just before the root node of the rewritten expression tree. See PR27273 for more info about such problems. Reviewers: dblaikie, aprantl, dexonsmith Reviewed By: aprantl Subscribers: JDevlieghere, llvm-commits Tags: #debug-info Differential Revision: https://reviews.llvm.org/D45975 llvm-svn: 330804 |
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| Analysis | ||
| Assembler | ||
| Bindings | ||
| Bitcode | ||
| BugPoint | ||
| CodeGen | ||
| DebugInfo | ||
| Examples | ||
| ExecutionEngine | ||
| Feature | ||
| FileCheck | ||
| Instrumentation | ||
| Integer | ||
| JitListener | ||
| LTO | ||
| Linker | ||
| MC | ||
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| ObjectYAML | ||
| Other | ||
| SafepointIRVerifier | ||
| SymbolRewriter | ||
| TableGen | ||
| ThinLTO/X86 | ||
| Transforms | ||
| Unit | ||
| Verifier | ||
| YAMLParser | ||
| tools | ||
| .clang-format | ||
| CMakeLists.txt | ||
| TestRunner.sh | ||
| lit.cfg.py | ||
| lit.site.cfg.py.in | ||