[llvm] [SampleFDO][TypeProf]Support vtable type profiling for ext-binary and text format (PR #148002)

[Snehasish Kumar via llvm-commits]

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@@ -197,8 +197,32 @@ enum class LineType {
   CallSiteProfile,
   BodyProfile,
   Metadata,
+  VirtualCallTypeProfile,
 };
 
+// Parse `Input` as a white-space separated list of `vtable:count` pairs. An
+// example input line is `_ZTVbar:1471 _ZTVfoo:630`.
+static bool parseTypeCountMap(StringRef Input,
+                              DenseMap<StringRef, uint64_t> &TypeCountMap) {
+  for (size_t Index = Input.find_first_not_of(' '); Index != StringRef::npos;) {
+    size_t n1 = Input.find(':', Index);
+    if (n1 == StringRef::npos)
+      return false; // No colon found, invalid format.
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snehasish wrote:

Since we know the failure reason, it would be good to return a more structured error (e.g. llvm::Error) with a message to help the user.

https://github.com/llvm/llvm-project/pull/148002