[Clang][Interp] __builtin_os_log_format_buffer_size should be an unevaluated builtin (#99895)

Follow the current behavior of constant evaluator,
`__builtin_os_log_format_buffer_size` should be an unevaluated builtin.

The following code is well-formed:
```
void test_builtin_os_log(void *buf, int i, const char *data) {
  constexpr int len = __builtin_os_log_format_buffer_size("%d %{public}s %{private}.16P", i, data, data);
}
```

Signed-off-by: yronglin <[email protected]>

Author: yronglin

clang/lib/AST/Interp/ByteCodeEmitter.cpp

@@ -27,7 +27,8 @@ using namespace clang::interp;
 /// Similar information is available via ASTContext::BuiltinInfo,
 /// but that is not correct for our use cases.
 static bool isUnevaluatedBuiltin(unsigned BuiltinID) {
-  return BuiltinID == Builtin::BI__builtin_classify_type;
+  return BuiltinID == Builtin::BI__builtin_classify_type ||
+         BuiltinID == Builtin::BI__builtin_os_log_format_buffer_size;
 }
 
 Function *ByteCodeEmitter::compileFunc(const FunctionDecl *FuncDecl) {

clang/test/CodeGen/builtins.c

@@ -1,6 +1,7 @@
 // RUN: %clang_cc1 -emit-llvm -o %t %s
 // RUN: not grep __builtin %t
 // RUN: %clang_cc1 -emit-llvm -triple x86_64-darwin-apple -o - %s | FileCheck %s
+// RUN: %clang_cc1 -emit-llvm -triple x86_64-darwin-apple -fexperimental-new-constant-interpreter -o - %s | FileCheck %s
 
 int printf(const char *, ...);