forked from OSchip/llvm-project
9ea2c01264
Summary: Before this change, LLVM would always describe locals on the stack as being relative to some specific register, RSP, ESP, EBP, ESI, etc. Variables in stack memory are pretty common, so there is a special S_DEFRANGE_FRAMEPOINTER_REL symbol for them. This change uses it to reduce the size of our debug info. On top of the size savings, there are cases on 32-bit x86 where local variables are addressed from ESP, but ESP changes across the function. Unlike in DWARF, there is no FPO data to describe the stack adjustments made to push arguments onto the stack and pop them off after the call, which makes it hard for the debugger to find the local variables in frames further up the stack. To handle this, CodeView has a special VFRAME register, which corresponds to the $T0 variable set by our FPO data in 32-bit. Offsets to local variables are instead relative to this value. This is part of PR38857. Reviewers: hans, zturner, javed.absar Subscribers: aprantl, hiraditya, JDevlieghere, llvm-commits Differential Revision: https://reviews.llvm.org/D52217 llvm-svn: 343543 |
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| .. | ||
| AppendingTypeTableBuilder.cpp | ||
| CMakeLists.txt | ||
| CVSymbolVisitor.cpp | ||
| CVTypeVisitor.cpp | ||
| CodeViewError.cpp | ||
| CodeViewRecordIO.cpp | ||
| ContinuationRecordBuilder.cpp | ||
| DebugChecksumsSubsection.cpp | ||
| DebugCrossExSubsection.cpp | ||
| DebugCrossImpSubsection.cpp | ||
| DebugFrameDataSubsection.cpp | ||
| DebugInlineeLinesSubsection.cpp | ||
| DebugLinesSubsection.cpp | ||
| DebugStringTableSubsection.cpp | ||
| DebugSubsection.cpp | ||
| DebugSubsectionRecord.cpp | ||
| DebugSubsectionVisitor.cpp | ||
| DebugSymbolRVASubsection.cpp | ||
| DebugSymbolsSubsection.cpp | ||
| EnumTables.cpp | ||
| Formatters.cpp | ||
| GlobalTypeTableBuilder.cpp | ||
| LLVMBuild.txt | ||
| LazyRandomTypeCollection.cpp | ||
| Line.cpp | ||
| MergingTypeTableBuilder.cpp | ||
| RecordName.cpp | ||
| RecordSerialization.cpp | ||
| SimpleTypeSerializer.cpp | ||
| StringsAndChecksums.cpp | ||
| SymbolDumper.cpp | ||
| SymbolRecordMapping.cpp | ||
| SymbolSerializer.cpp | ||
| TypeDumpVisitor.cpp | ||
| TypeHashing.cpp | ||
| TypeIndex.cpp | ||
| TypeIndexDiscovery.cpp | ||
| TypeRecordHelpers.cpp | ||
| TypeRecordMapping.cpp | ||
| TypeStreamMerger.cpp | ||
| TypeTableCollection.cpp | ||