[clang] [CIR] Add support for emitting predefined expressions (PR #161757)

[Erich Keane via cfe-commits]

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@@ -2372,6 +2373,21 @@ mlir::Value CIRGenFunction::emitScalarConstant(
   return builder.getConstant(getLoc(e->getSourceRange()), constant.getValue());
 }
 
+LValue CIRGenFunction::emitPredefinedLValue(const PredefinedExpr *e) {
+  const StringLiteral *sl = e->getFunctionName();
+  assert(sl != nullptr && "No StringLiteral name in PredefinedExpr");
+  auto fn = cast<cir::FuncOp>(curFn);
+  StringRef fnName = fn.getName();
+  fnName.consume_front("\01");
+  StringRef nameItems[] = {PredefinedExpr::getIdentKindName(e->getIdentKind()),
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erichkeane wrote:

can we just make this a std::array<StringRef,2> here?  That way we can use the range-version of llvm::join and not  have the magic 2 there (and yes, i know we'd have it HERE, but at least then the compiler would figure it out).

https://github.com/llvm/llvm-project/pull/161757