[llvm] [llvm][ctx_profile] Add the `llvm.instrprof.callsite` intrinsic (PR #89939)

[Mircea Trofin via llvm-commits]

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@@ -291,6 +291,8 @@ Value *InstrProfIncrementInst::getStep() const {
   return ConstantInt::get(Type::getInt64Ty(Context), 1);
 }
 
+Value *InstrProfCallsite::getCallee() const { return getArgOperand(4); }
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mtrofin wrote:

good point, because nothing stops someone from `reinterpret_cast`-ing. Fixed.

https://github.com/llvm/llvm-project/pull/89939