From 98763433e66dd91bf5f10b1daf03d9373f07912a Mon Sep 17 00:00:00 2001
From: Timm Baeder <tbaeder@redhat.com>
Date: Tue, 13 May 2025 10:55:24 +0200
Subject: [PATCH] [clang][bytecode] Optimize enum value range checks (#139672)

Only do the work if we really have to.
---
 clang/lib/AST/ByteCode/Interp.cpp | 5 ++---
 clang/lib/AST/ByteCode/Interp.h   | 5 +++--
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/clang/lib/AST/ByteCode/Interp.cpp b/clang/lib/AST/ByteCode/Interp.cpp
index 43f8d156589b..91930c016c98 100644
--- a/clang/lib/AST/ByteCode/Interp.cpp
+++ b/clang/lib/AST/ByteCode/Interp.cpp
@@ -1251,12 +1251,11 @@ bool Free(InterpState &S, CodePtr OpPC, bool DeleteIsArrayForm,
 
 void diagnoseEnumValue(InterpState &S, CodePtr OpPC, const EnumDecl *ED,
                        const APSInt &Value) {
-  llvm::APInt Min;
-  llvm::APInt Max;
-
   if (S.EvaluatingDecl && !S.EvaluatingDecl->isConstexpr())
     return;
 
+  llvm::APInt Min;
+  llvm::APInt Max;
   ED->getValueRange(Max, Min);
   --Max;
 
diff --git a/clang/lib/AST/ByteCode/Interp.h b/clang/lib/AST/ByteCode/Interp.h
index a13fd6c1f1da..35d97167135f 100644
--- a/clang/lib/AST/ByteCode/Interp.h
+++ b/clang/lib/AST/ByteCode/Interp.h
@@ -3026,10 +3026,11 @@ template <PrimType Name, class T = typename PrimConv<Name>::T>
 inline bool CheckEnumValue(InterpState &S, CodePtr OpPC, const EnumDecl *ED) {
   assert(ED);
   assert(!ED->isFixed());
-  const APSInt Val = S.Stk.peek<T>().toAPSInt();
 
-  if (S.inConstantContext())
+  if (S.inConstantContext()) {
+    const APSInt Val = S.Stk.peek<T>().toAPSInt();
     diagnoseEnumValue(S, OpPC, ED, Val);
+  }
   return true;
 }