[llvm] `dwarf2yaml.cpp` optimizations (PR #179048)

[via llvm-commits]

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@@ -123,16 +126,19 @@ Error dumpDebugARanges(DWARFContext &DCtx, DWARFYAML::Data &Y) {
     Range.CuOffset = Set.getHeader().CuOffset;
     Range.AddrSize = Set.getHeader().AddrSize;
     Range.SegSize = Set.getHeader().SegSize;
+
+    Range.Descriptors.reserve(Set.descriptors().end() -
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serge-sans-paille wrote:

nit: `std::distance` ?

https://github.com/llvm/llvm-project/pull/179048