[llvm] [CodeGen] Add -force-emit-call-site-info LLVM flag (PR #206668)

[Zhaoxuan Jiang via llvm-commits]

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@@ -65,3 +71,7 @@ bool TargetOptions::ShouldEmitDebugEntryValues() const {
   return (SupportsDebugEntryValues && DebuggerTuning != DebuggerKind::SCE) ||
          EnableDebugEntryValues;
 }
+
+bool TargetOptions::ShouldEmitCallSiteInfo() const {
+  return EmitCallSiteInfo || ForceEmitCallSiteInfo;
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nocchijiang wrote:

The existing `EmitCallSiteInfo` is registered in CommandFlags.cpp, it has no effect via `-mllvm`.

The `cl::opt` introduced here is a regular LLVM flag that works through any frontend's passthrough without source changes. This is discussed in more detail in the [RFC](https://discourse.llvm.org/t/rfc-enhancements-to-machine-outliner-for-ios-aarch64/89807/6).

Would you prefer we drop the existing codegen flag and keep only the new `cl::opt`?

https://github.com/llvm/llvm-project/pull/206668