[compiler-rt] [llvm] [llvm-cov][gcov] Support multi-files coverage in one basic block (PR #144504)

[Fangrui Song via llvm-commits]

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@@ -322,7 +320,7 @@ namespace {
     GCOVBlock(GCOVProfiler *P, uint32_t Number)
         : GCOVRecord(P), Number(Number) {}
 
-    StringMap<GCOVLines> LinesByFile;
+    SmallVector<GCOVLines, 4> Lines;
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MaskRay wrote:

inline element count of 4 is wasteful. Just use 0.

https://github.com/llvm/llvm-project/pull/144504