Revert "Add support for attribute 'noescape'."

This reverts commit r313722.

It looks like compiler-rt/lib/tsan/rtl/tsan_libdispatch_mac.cc cannot be
compiled because some of the functions declared in the file do not match
the ones in the SDK headers (which are annotated with 'noescape').

llvm-svn: 313725

9 files changed, 20 insertions, 132 deletions

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 82e74528d19..4d26748b077 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -7968,17 +7968,9 @@ QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
     if (lproto->getTypeQuals() != rproto->getTypeQuals())
       return QualType();
 
-    SmallVector<FunctionProtoType::ExtParameterInfo, 4> newParamInfos;
-    bool canUseLeft, canUseRight;
-    if (!mergeExtParameterInfo(lproto, rproto, canUseLeft, canUseRight,
-                               newParamInfos))
+    if (!doFunctionTypesMatchOnExtParameterInfos(rproto, lproto))
       return QualType();
 
-    if (!canUseLeft)
-      allLTypes = false;
-    if (!canUseRight)
-      allRTypes = false;
-
     // Check parameter type compatibility
     SmallVector<QualType, 10> types;
     for (unsigned i = 0, n = lproto->getNumParams(); i < n; i++) {
@@ -8009,8 +8001,6 @@ QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
 
     FunctionProtoType::ExtProtoInfo EPI = lproto->getExtProtoInfo();
     EPI.ExtInfo = einfo;
-    EPI.ExtParameterInfos =
-        newParamInfos.empty() ? nullptr : newParamInfos.data();
     return getFunctionType(retType, types, EPI);
   }
 
@@ -8370,50 +8360,26 @@ QualType ASTContext::mergeTypes(QualType LHS, QualType RHS,
   llvm_unreachable("Invalid Type::Class!");
 }
 
-bool ASTContext::mergeExtParameterInfo(
-    const FunctionProtoType *FirstFnType, const FunctionProtoType *SecondFnType,
-    bool &CanUseFirst, bool &CanUseSecond,
-    SmallVectorImpl<FunctionProtoType::ExtParameterInfo> &NewParamInfos) {
-  assert(NewParamInfos.empty() && "param info list not empty");
-  CanUseFirst = CanUseSecond = true;
-  bool FirstHasInfo = FirstFnType->hasExtParameterInfos();
-  bool SecondHasInfo = SecondFnType->hasExtParameterInfos();
-
+bool ASTContext::doFunctionTypesMatchOnExtParameterInfos(
+                   const FunctionProtoType *firstFnType,
+                   const FunctionProtoType *secondFnType) {
   // Fast path: if the first type doesn't have ext parameter infos,
-  // we match if and only if the second type also doesn't have them.
-  if (!FirstHasInfo && !SecondHasInfo)
-    return true;
+  // we match if and only if they second type also doesn't have them.
+  if (!firstFnType->hasExtParameterInfos())
+    return !secondFnType->hasExtParameterInfos();
 
-  bool NeedParamInfo = false;
-  size_t E = FirstHasInfo ? FirstFnType->getExtParameterInfos().size()
-                          : SecondFnType->getExtParameterInfos().size();
+  // Otherwise, we can only match if the second type has them.
+  if (!secondFnType->hasExtParameterInfos())
+    return false;
 
-  for (size_t I = 0; I < E; ++I) {
-    FunctionProtoType::ExtParameterInfo FirstParam, SecondParam;
-    if (FirstHasInfo)
-      FirstParam = FirstFnType->getExtParameterInfo(I);
-    if (SecondHasInfo)
-      SecondParam = SecondFnType->getExtParameterInfo(I);
+  auto firstEPI = firstFnType->getExtParameterInfos();
+  auto secondEPI = secondFnType->getExtParameterInfos();
+  assert(firstEPI.size() == secondEPI.size());
 
-    // Cannot merge unless everything except the noescape flag matches.
-    if (FirstParam.withIsNoEscape(false) != SecondParam.withIsNoEscape(false))
+  for (size_t i = 0, n = firstEPI.size(); i != n; ++i) {
+    if (firstEPI[i] != secondEPI[i])
       return false;
-
-    bool FirstNoEscape = FirstParam.isNoEscape();
-    bool SecondNoEscape = SecondParam.isNoEscape();
-    bool IsNoEscape = FirstNoEscape && SecondNoEscape;
-    NewParamInfos.push_back(FirstParam.withIsNoEscape(IsNoEscape));
-    if (NewParamInfos.back().getOpaqueValue())
-      NeedParamInfo = true;
-    if (FirstNoEscape != IsNoEscape)
-      CanUseFirst = false;
-    if (SecondNoEscape != IsNoEscape)
-      CanUseSecond = false;
   }
-
-  if (!NeedParamInfo)
-    NewParamInfos.clear();
-
   return true;
 }
 
diff --git a/clang/lib/AST/ItaniumMangle.cpp b/clang/lib/AST/ItaniumMangle.cpp
index a9c5ab2cc1d..dbda7a5dbd4 100644
--- a/clang/lib/AST/ItaniumMangle.cpp
+++ b/clang/lib/AST/ItaniumMangle.cpp
@@ -2643,9 +2643,6 @@ CXXNameMangler::mangleExtParameterInfo(FunctionProtoType::ExtParameterInfo PI) {
 
   if (PI.isConsumed())
     mangleVendorQualifier("ns_consumed");
-
-  if (PI.isNoEscape())
-    mangleVendorQualifier("noescape");
 }
 
 // <type>          ::= <function-type>
diff --git a/clang/lib/AST/TypePrinter.cpp b/clang/lib/AST/TypePrinter.cpp
index 1f5b4834896..15c63bf4ed9 100644
--- a/clang/lib/AST/TypePrinter.cpp
+++ b/clang/lib/AST/TypePrinter.cpp
@@ -665,8 +665,6 @@ void TypePrinter::printFunctionProtoAfter(const FunctionProtoType *T,
 
       auto EPI = T->getExtParameterInfo(i);
       if (EPI.isConsumed()) OS << "__attribute__((ns_consumed)) ";
-      if (EPI.isNoEscape())
-        OS << "__attribute__((noescape)) ";
       auto ABI = EPI.getABI();
       if (ABI != ParameterABI::Ordinary)
         OS << "__attribute__((" << getParameterABISpelling(ABI) << ")) ";
diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index a432c3ca20d..c6988b5a9f3 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -455,15 +455,11 @@ const CGFunctionInfo &
 CodeGenTypes::arrangeObjCMessageSendSignature(const ObjCMethodDecl *MD,
                                               QualType receiverType) {
   SmallVector<CanQualType, 16> argTys;
-  SmallVector<FunctionProtoType::ExtParameterInfo, 4> extParamInfos(2);
   argTys.push_back(Context.getCanonicalParamType(receiverType));
   argTys.push_back(Context.getCanonicalParamType(Context.getObjCSelType()));
   // FIXME: Kill copy?
   for (const auto *I : MD->parameters()) {
     argTys.push_back(Context.getCanonicalParamType(I->getType()));
-    auto extParamInfo = FunctionProtoType::ExtParameterInfo().withIsNoEscape(
-        I->hasAttr<NoEscapeAttr>());
-    extParamInfos.push_back(extParamInfo);
   }
 
   FunctionType::ExtInfo einfo;
@@ -479,7 +475,7 @@ CodeGenTypes::arrangeObjCMessageSendSignature(const ObjCMethodDecl *MD,
 
   return arrangeLLVMFunctionInfo(
       GetReturnType(MD->getReturnType()), /*instanceMethod=*/false,
-      /*chainCall=*/false, argTys, einfo, extParamInfos, required);
+      /*chainCall=*/false, argTys, einfo, {}, required);
 }
 
 const CGFunctionInfo &
@@ -2097,9 +2093,6 @@ void CodeGenModule::ConstructAttributeList(
       break;
     }
 
-    if (FI.getExtParameterInfo(ArgNo).isNoEscape())
-      Attrs.addAttribute(llvm::Attribute::NoCapture);
-
     if (Attrs.hasAttributes()) {
       unsigned FirstIRArg, NumIRArgs;
       std::tie(FirstIRArg, NumIRArgs) = IRFunctionArgs.getIRArgs(ArgNo);
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index cffb860638d..b8432ebd53b 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -1531,22 +1531,6 @@ static void handleReturnsNonNullAttr(Sema &S, Decl *D,
                                Attr.getAttributeSpellingListIndex()));
 }
 
-static void handleNoEscapeAttr(Sema &S, Decl *D, const AttributeList &Attr) {
-  if (D->isInvalidDecl())
-    return;
-
-  // noescape only applies to pointer types.
-  QualType T = cast<ParmVarDecl>(D)->getType();
-  if (!S.isValidPointerAttrType(T, /* RefOkay */ true)) {
-    S.Diag(Attr.getLoc(), diag::warn_attribute_pointers_only)
-        << Attr.getName() << Attr.getRange() << 0;
-    return;
-  }
-
-  D->addAttr(::new (S.Context) NoEscapeAttr(
-      Attr.getRange(), S.Context, Attr.getAttributeSpellingListIndex()));
-}
-
 static void handleAssumeAlignedAttr(Sema &S, Decl *D,
                                     const AttributeList &Attr) {
   Expr *E = Attr.getArgAsExpr(0),
@@ -6183,9 +6167,6 @@ static void ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D,
   case AttributeList::AT_ReturnsNonNull:
     handleReturnsNonNullAttr(S, D, Attr);
     break;
-  case AttributeList::AT_NoEscape:
-    handleNoEscapeAttr(S, D, Attr);
-    break;
   case AttributeList::AT_AssumeAligned:
     handleAssumeAlignedAttr(S, D, Attr);
     break;
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 312e0e24828..529084a517b 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -14081,21 +14081,8 @@ void Sema::DiagnoseReturnInConstructorExceptionHandler(CXXTryStmt *TryBlock) {
 
 bool Sema::CheckOverridingFunctionAttributes(const CXXMethodDecl *New,
                                              const CXXMethodDecl *Old) {
-  const auto *NewFT = New->getType()->getAs<FunctionProtoType>();
-  const auto *OldFT = Old->getType()->getAs<FunctionProtoType>();
-
-  if (OldFT->hasExtParameterInfos()) {
-    for (unsigned I = 0, E = OldFT->getNumParams(); I != E; ++I)
-      // A parameter of the overriding method should be annotated with noescape
-      // if the corresponding parameter of the overridden method is annotated.
-      if (OldFT->getExtParameterInfo(I).isNoEscape() &&
-          !NewFT->getExtParameterInfo(I).isNoEscape()) {
-        Diag(New->getParamDecl(I)->getLocation(),
-             diag::warn_overriding_method_missing_noescape);
-        Diag(Old->getParamDecl(I)->getLocation(),
-             diag::note_overridden_marked_noescape);
-      }
-  }
+  const FunctionType *NewFT = New->getType()->getAs<FunctionType>();
+  const FunctionType *OldFT = Old->getType()->getAs<FunctionType>();
 
   CallingConv NewCC = NewFT->getCallConv(), OldCC = OldFT->getCallConv();
 
diff --git a/clang/lib/Sema/SemaDeclObjC.cpp b/clang/lib/Sema/SemaDeclObjC.cpp
index 6b33f7c64ce..5f9f608b75c 100644
--- a/clang/lib/Sema/SemaDeclObjC.cpp
+++ b/clang/lib/Sema/SemaDeclObjC.cpp
@@ -188,14 +188,6 @@ void Sema::CheckObjCMethodOverride(ObjCMethodDecl *NewMethod,
       Diag(newDecl->getLocation(), diag::warn_nsconsumed_attribute_mismatch);
       Diag(oldDecl->getLocation(), diag::note_previous_decl) << "parameter";
     }
-
-    // A parameter of the overriding method should be annotated with noescape
-    // if the corresponding parameter of the overridden method is annotated.
-    if (oldDecl->hasAttr<NoEscapeAttr>() && !newDecl->hasAttr<NoEscapeAttr>()) {
-      Diag(newDecl->getLocation(),
-           diag::warn_overriding_method_missing_noescape);
-      Diag(oldDecl->getLocation(), diag::note_overridden_marked_noescape);
-    }
   }
 }
 
diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index 8f28ec2fb8a..36f24fd9c46 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -1481,23 +1481,6 @@ bool Sema::IsFunctionConversion(QualType FromType, QualType ToType,
                  .getTypePtr());
       Changed = true;
     }
-
-    // Convert FromFPT's ExtParameterInfo if necessary. The conversion is valid
-    // only if the ExtParameterInfo lists of the two function prototypes can be
-    // merged and the merged list is identical to ToFPT's ExtParameterInfo list.
-    SmallVector<FunctionProtoType::ExtParameterInfo, 4> NewParamInfos;
-    bool CanUseToFPT, CanUseFromFPT;
-    if (Context.mergeExtParameterInfo(ToFPT, FromFPT, CanUseToFPT,
-                                      CanUseFromFPT, NewParamInfos) &&
-        CanUseToFPT && !CanUseFromFPT) {
-      FunctionProtoType::ExtProtoInfo ExtInfo = FromFPT->getExtProtoInfo();
-      ExtInfo.ExtParameterInfos =
-          NewParamInfos.empty() ? nullptr : NewParamInfos.data();
-      QualType QT = Context.getFunctionType(FromFPT->getReturnType(),
-                                            FromFPT->getParamTypes(), ExtInfo);
-      FromFn = QT->getAs<FunctionType>();
-      Changed = true;
-    }
   }
 
   if (!Changed)
@@ -2680,12 +2663,8 @@ bool Sema::IsBlockPointerConversion(QualType FromType, QualType ToType,
        // Argument types are too different. Abort.
        return false;
    }
-
-   SmallVector<FunctionProtoType::ExtParameterInfo, 4> NewParamInfos;
-   bool CanUseToFPT, CanUseFromFPT;
-   if (!Context.mergeExtParameterInfo(ToFunctionType, FromFunctionType,
-                                      CanUseToFPT, CanUseFromFPT,
-                                      NewParamInfos))
+   if (!Context.doFunctionTypesMatchOnExtParameterInfos(FromFunctionType,
+                                                        ToFunctionType))
      return false;
 
    ConvertedType = ToType;
diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
index f35eef2d4f7..c4d7bb1f36a 100644
--- a/clang/lib/Sema/SemaType.cpp
+++ b/clang/lib/Sema/SemaType.cpp
@@ -4479,11 +4479,6 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
             HasAnyInterestingExtParameterInfos = true;
           }
 
-          if (Param->hasAttr<NoEscapeAttr>()) {
-            ExtParameterInfos[i] = ExtParameterInfos[i].withIsNoEscape(true);
-            HasAnyInterestingExtParameterInfos = true;
-          }
-
           ParamTys.push_back(ParamTy);
         }