[llvm] [llvm-symbolizer] Make symbolizer parse section relative syntax (PR #168524)

[James Henderson via llvm-commits]

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@@ -275,10 +274,9 @@ class LLVMSymbolizer {
 
   std::unique_ptr<BuildIDFetcher> BIDFetcher;
 
-  /// Cache for XCOFF section base addresses: (ModulePath, SectionTypeFlag) ->
+  /// Cache for XCOFF section base addresses: ModulePath -> SectionTypeFlag ->
   /// base VMA.
-  std::map<std::pair<std::string, XCOFF::SectionTypeFlags>, uint64_t>
-      XCOFFSectionBaseCache;
+  StringMap<DenseMap<XCOFF::SectionTypeFlags, uint64_t>> XCOFFSectionBaseCache;
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jh7370 wrote:

What's the motivation for a two-level map, rather what you had before where the path and section type were used together as a key?

https://github.com/llvm/llvm-project/pull/168524