From 38c5ebd7b1b65304c7b5c7b9bf3f9162df22e77d Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Sun, 19 Apr 2009 05:21:20 +0000
Subject: [PATCH] add a new Sema::CurFunctionNeedsScopeChecking bool that is
 used to avoid calling into the jump checker when a function or method is
 known to contain no VLAs or @try blocks.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@69509 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Sema/Sema.h           |  6 ++++++
 lib/Sema/SemaDecl.cpp     | 26 +++++++++++++++++---------
 lib/Sema/SemaDeclObjC.cpp |  2 ++
 lib/Sema/SemaStmt.cpp     |  1 +
 test/Sema/scope-check.c   | 11 ++---------
 5 files changed, 28 insertions(+), 18 deletions(-)

diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index b08a120e58..e8742e8e51 100644
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -153,6 +153,12 @@ public:
   /// handle the case when they are in a block.
   llvm::SmallVector<SwitchStmt*, 8> FunctionSwitchStack;
   
+  /// CurFunctionNeedsScopeChecking - This is set to true when a function or
+  /// ObjC method body contains a VLA or an ObjC try block, which introduce
+  /// scopes that need to be checked for goto conditions.  If a function does
+  /// not contain this, then it need not have the jump checker run on it.
+  bool CurFunctionNeedsScopeChecking;
+  
   /// ExtVectorDecls - This is a list all the extended vector types. This allows
   /// us to associate a raw vector type with one of the ext_vector type names.
   /// This is only necessary for issuing pretty diagnostics.
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 887c86cef5..7ed0e2dd31 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -1564,11 +1564,13 @@ Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
       InvalidDecl = true;
   }
 
-  if (S->getFnParent() == 0) {
-    QualType T = NewTD->getUnderlyingType();
-    // C99 6.7.7p2: If a typedef name specifies a variably modified type
-    // then it shall have block scope.
-    if (T->isVariablyModifiedType()) {
+  // C99 6.7.7p2: If a typedef name specifies a variably modified type
+  // then it shall have block scope.
+  QualType T = NewTD->getUnderlyingType();
+  if (T->isVariablyModifiedType()) {
+    CurFunctionNeedsScopeChecking = true;
+  
+    if (S->getFnParent() == 0) {
       bool SizeIsNegative;
       QualType FixedTy =
           TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative);
@@ -1810,9 +1812,12 @@ bool Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl,
       && !NewVD->hasAttr<BlocksAttr>())
     Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local);
 
-  bool isIllegalVLA = T->isVariableArrayType() && NewVD->hasGlobalStorage();
-  bool isIllegalVM = T->isVariablyModifiedType() && NewVD->hasLinkage();
-  if (isIllegalVLA || isIllegalVM) {
+  bool isVM = T->isVariablyModifiedType();
+  if (isVM || NewVD->hasAttr<CleanupAttr>())
+    CurFunctionNeedsScopeChecking = true;
+  
+  if ((isVM && NewVD->hasLinkage()) ||
+      (T->isVariableArrayType() && NewVD->hasGlobalStorage())) {
     bool SizeIsNegative;
     QualType FixedTy =
         TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative);
@@ -2822,6 +2827,8 @@ Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope,
 Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) {
   FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>());
 
+  CurFunctionNeedsScopeChecking = false;
+  
   // See if this is a redefinition.
   const FunctionDecl *Definition;
   if (FD->getBody(Context, Definition)) {
@@ -2964,7 +2971,8 @@ Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) {
   if (!Body) return D;
 
   // Verify that that gotos and switch cases don't jump into scopes illegally.
-  DiagnoseInvalidJumps(Body);
+  if (CurFunctionNeedsScopeChecking)
+    DiagnoseInvalidJumps(Body);
 
   return D;
 }
diff --git a/lib/Sema/SemaDeclObjC.cpp b/lib/Sema/SemaDeclObjC.cpp
index 208562f8f1..db81cacc2b 100644
--- a/lib/Sema/SemaDeclObjC.cpp
+++ b/lib/Sema/SemaDeclObjC.cpp
@@ -28,6 +28,8 @@ void Sema::ActOnStartOfObjCMethodDef(Scope *FnBodyScope, DeclPtrTy D) {
   if (!MDecl)
     return;
 
+  CurFunctionNeedsScopeChecking = false;
+
   // Allow the rest of sema to find private method decl implementations.
   if (MDecl->isInstanceMethod())
     AddInstanceMethodToGlobalPool(MDecl);
diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp
index 4a5facb39c..35dffa10f2 100644
--- a/lib/Sema/SemaStmt.cpp
+++ b/lib/Sema/SemaStmt.cpp
@@ -1056,6 +1056,7 @@ Sema::ActOnObjCAtFinallyStmt(SourceLocation AtLoc, StmtArg Body) {
 Action::OwningStmtResult
 Sema::ActOnObjCAtTryStmt(SourceLocation AtLoc,
                          StmtArg Try, StmtArg Catch, StmtArg Finally) {
+  CurFunctionNeedsScopeChecking = true;
   return Owned(new (Context) ObjCAtTryStmt(AtLoc,
                                         static_cast<Stmt*>(Try.release()),
                                         static_cast<Stmt*>(Catch.release()),
diff --git a/test/Sema/scope-check.c b/test/Sema/scope-check.c
index 1d1c5aa2f9..59fd832dc6 100644
--- a/test/Sema/scope-check.c
+++ b/test/Sema/scope-check.c
@@ -164,8 +164,9 @@ L2:
   return;
 }
 
+
 // TODO: When and if gotos are allowed in blocks, this should work.
-void test11(int n) {
+void test13(int n) {
   void *P = ^{
     goto L1;  // expected-error {{goto not allowed in block literal}}
   L1:
@@ -180,11 +181,3 @@ void test11(int n) {
   };
 }
 
-
-
-#if 0
-// in Sema::CheckVariableDeclaration
-// FIXME: This won't give the correct result for
-// int a[10][n];    
-#endif
-
-- 
2.40.0