supython-coder
diff --git a/‎clang/include/clang/AST/Stmt.h
Lines changed: 4 additions & 0 deletions b/‎clang/include/clang/AST/Stmt.h
Lines changed: 4 additions & 0 deletions
diff --git a/‎clang/include/clang/Sema/Sema.h
Lines changed: 1 addition & 1 deletion b/‎clang/include/clang/Sema/Sema.h
Lines changed: 1 addition & 1 deletion
diff --git a/‎clang/lib/AST/Stmt.cpp
Lines changed: 6 additions & 0 deletions b/‎clang/lib/AST/Stmt.cpp
Lines changed: 6 additions & 0 deletions
@@ -1995,6 +1995,10 @@ class IfStmt final
   bool isConstexpr() const { return IfStmtBits.IsConstexpr; }
   void setConstexpr(bool C) { IfStmtBits.IsConstexpr = C; }
 
+  /// If this is an 'if constexpr', determine which substatement will be taken.
+  /// Otherwise, or if the condition is value-dependent, returns None.
+  Optional<const Stmt*> getNondiscardedCase(const ASTContext &Ctx) const;
+
   bool isObjCAvailabilityCheck() const;
 
   SourceLocation getBeginLoc() const { return getIfLoc(); }
 
@@ -1599,7 +1599,7 @@ class Sema final {
   DeclarationNameInfo GetNameFromUnqualifiedId(const UnqualifiedId &Name);
   static QualType GetTypeFromParser(ParsedType Ty,
                                     TypeSourceInfo **TInfo = nullptr);
-  CanThrowResult canThrow(const Expr *E);
+  CanThrowResult canThrow(const Stmt *E);
   const FunctionProtoType *ResolveExceptionSpec(SourceLocation Loc,
                                                 const FunctionProtoType *FPT);
   void UpdateExceptionSpec(FunctionDecl *FD,
 
@@ -908,6 +908,12 @@ bool IfStmt::isObjCAvailabilityCheck() const {
   return isa<ObjCAvailabilityCheckExpr>(getCond());
 }
 
+Optional<const Stmt*> IfStmt::getNondiscardedCase(const ASTContext &Ctx) const {
+  if (!isConstexpr() || getCond()->isValueDependent())
+    return None;
+  return !getCond()->EvaluateKnownConstInt(Ctx) ? getElse() : getThen();
+}
+
 ForStmt::ForStmt(const ASTContext &C, Stmt *Init, Expr *Cond, VarDecl *condVar,
                  Expr *Inc, Stmt *Body, SourceLocation FL, SourceLocation LP,
                  SourceLocation RP)