[clang] [ObjC] Emit number, array, and dictionary literals as constants (PR #185130)

[Oliver Hunt via cfe-commits]

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@@ -0,0 +1,201 @@
+//===-- CodeGen/CGObjCMacConstantLiteralUtil.h - ----------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This should be used for things that effect the ABI of
+// Obj-C constant initializer literals (`-fobjc-constant-literals`) to allow
+// future changes without breaking the ABI promises.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_CODEGEN_CGOBJCMACCONSTANTLITERALUTIL_H
+#define LLVM_CLANG_LIB_CODEGEN_CGOBJCMACCONSTANTLITERALUTIL_H
+
+#include "CGObjCRuntime.h"
+#include "clang/AST/ExprObjC.h"
+#include "clang/AST/Type.h"
+#include "llvm/ADT/APFloat.h"
+#include "llvm/ADT/APSInt.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/DenseMapInfo.h"
+#include <numeric>
+
+namespace clang {
+namespace CodeGen {
+namespace CGObjCMacConstantLiteralUtil {
+
+class NSConstantNumberMapInfo {
+
+  enum class MapInfoType {
+    Empty,
+    Tombstone,
+    Int,
+    Float,
+  };
+
+  MapInfoType InfoType;
+  QualType QType;
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ojhunt wrote:

Maybe use CanQualType instead?

https://github.com/llvm/llvm-project/pull/185130