[llvm] [llvm-profgen] Loading binary functions from .symtab when DWARF info is incomplete (PR #163654)

[Lei Wang via llvm-commits]

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@@ -820,6 +822,48 @@ void ProfiledBinary::populateSymbolAddressList(const ObjectFile *Obj) {
   }
 }
 
+void ProfiledBinary::populateSymbolsFromElf(const ObjectFile *Obj) {
+  // Load binary functions from ELF symbol table when DWARF info is incomplete
+  StringRef FileName = Obj->getFileName();
+  for (const ELFSymbolRef Symbol : Obj->symbols()) {
+    const SymbolRef::Type Type = unwrapOrError(Symbol.getType(), FileName);
+    const uint64_t Addr = unwrapOrError(Symbol.getAddress(), FileName);
+    const StringRef Name = unwrapOrError(Symbol.getName(), FileName);
+    const uint64_t Size = Symbol.getSize();
+
+    if (Size == 0 || Type != SymbolRef::ST_Function)
+      continue;
+
+    SmallVector<StringRef> Suffixes(
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wlei-llvm wrote:

Similar to my previous comment, this is inside a hot loop, I guess this introduce the alloc/dealloc overheads, we may find a more efficient way(at least we can hoist loop invariant part).

https://github.com/llvm/llvm-project/pull/163654