[llvm] Make `IntrinsicLowering` external function call lowering configurable (PR #102148)

[Jannik Silvanus via llvm-commits]

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@@ -15,17 +15,29 @@
 #ifndef LLVM_CODEGEN_INTRINSICLOWERING_H
 #define LLVM_CODEGEN_INTRINSICLOWERING_H
 
+#include "llvm/ADT/ArrayRef.h"
+
 namespace llvm {
 class CallInst;
 class DataLayout;
+class Type;
+class Value;
 
 class IntrinsicLowering {
   const DataLayout &DL;
+  bool LowerExternalFunctionCalls;
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jasilvanus wrote:

This should be called something like `AllowLibraryFunctionCalls` as these function calls are created, not lowered.
Also, the new argument warrants a comment explaining what it does.

https://github.com/llvm/llvm-project/pull/102148