Re-land "MS ABI: lambda call operators are instance methods and should use thiscall"

Update the test cases to pass when lambda call operators use thiscall.

Update the lambda-to-block conversion operator to use the default free
function calling convention instead of the call operator's convention.

This reverts commit r233082 and re-instates r233023.

llvm-svn: 233835

8 files changed, 61 insertions, 36 deletions

diff --git a/clang/lib/Sema/SemaLambda.cpp b/clang/lib/Sema/SemaLambda.cpp
index 90a81f4ec45..147dd7ef210 100644
--- a/clang/lib/Sema/SemaLambda.cpp
+++ b/clang/lib/Sema/SemaLambda.cpp
@@ -1340,22 +1340,27 @@ static void addBlockPointerConversion(Sema &S,
                                       SourceRange IntroducerRange,
                                       CXXRecordDecl *Class,
                                       CXXMethodDecl *CallOperator) {
-  const FunctionProtoType *Proto
-    = CallOperator->getType()->getAs<FunctionProtoType>(); 
-  QualType BlockPtrTy;
-  {
-    FunctionProtoType::ExtProtoInfo ExtInfo = Proto->getExtProtoInfo();
-    ExtInfo.TypeQuals = 0;
-    QualType FunctionTy = S.Context.getFunctionType(
-        Proto->getReturnType(), Proto->getParamTypes(), ExtInfo);
-    BlockPtrTy = S.Context.getBlockPointerType(FunctionTy);
-  }
+  const FunctionProtoType *Proto =
+      CallOperator->getType()->getAs<FunctionProtoType>();
+
+  // The function type inside the block pointer type is the same as the call
+  // operator with some tweaks. The calling convention is the default free
+  // function convention, and the type qualifications are lost.
+  FunctionProtoType::ExtProtoInfo BlockEPI = Proto->getExtProtoInfo();
+  BlockEPI.ExtInfo =
+      BlockEPI.ExtInfo.withCallingConv(S.Context.getDefaultCallingConvention(
+          Proto->isVariadic(), /*IsCXXMethod=*/false));
+  BlockEPI.TypeQuals = 0;
+  QualType FunctionTy = S.Context.getFunctionType(
+      Proto->getReturnType(), Proto->getParamTypes(), BlockEPI);
+  QualType BlockPtrTy = S.Context.getBlockPointerType(FunctionTy);
+
+  FunctionProtoType::ExtProtoInfo ConversionEPI(
+      S.Context.getDefaultCallingConvention(
+          /*IsVariadic=*/false, /*IsCXXMethod=*/true));
+  ConversionEPI.TypeQuals = Qualifiers::Const;
+  QualType ConvTy = S.Context.getFunctionType(BlockPtrTy, None, ConversionEPI);
 
-  FunctionProtoType::ExtProtoInfo ExtInfo(S.Context.getDefaultCallingConvention(
-      /*IsVariadic=*/false, /*IsCXXMethod=*/true));
-  ExtInfo.TypeQuals = Qualifiers::Const;
-  QualType ConvTy = S.Context.getFunctionType(BlockPtrTy, None, ExtInfo);
-  
   SourceLocation Loc = IntroducerRange.getBegin();
   DeclarationName Name
     = S.Context.DeclarationNames.getCXXConversionFunctionName(
diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
index 485b70a4f9b..5a6cc2eabe3 100644
--- a/clang/lib/Sema/SemaType.cpp
+++ b/clang/lib/Sema/SemaType.cpp
@@ -2483,6 +2483,10 @@ getCCForDeclaratorChunk(Sema &S, Declarator &D,
       // in a member pointer.
       IsCXXInstanceMethod =
           D.getTypeObject(I).Kind == DeclaratorChunk::MemberPointer;
+    } else if (D.getContext() == Declarator::LambdaExprContext) {
+      // This can only be a call operator for a lambda, which is an instance
+      // method.
+      IsCXXInstanceMethod = true;
     } else {
       // We're the innermost decl chunk, so must be a function declarator.
       assert(D.isFunctionDeclarator());
diff --git a/clang/test/CodeGenCXX/mangle-ms-cxx14.cpp b/clang/test/CodeGenCXX/mangle-ms-cxx14.cpp
index a3a86851f7f..51627dd89e1 100644
--- a/clang/test/CodeGenCXX/mangle-ms-cxx14.cpp
+++ b/clang/test/CodeGenCXX/mangle-ms-cxx14.cpp
@@ -35,10 +35,10 @@ auto TemplateFuncionWithLocalLambda(T) {
   return LocalLambdaWithLocalType();
 }
 
-// MSVC2013-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?2???R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBA?A?3@XZ@A"
-// MSVC2013-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?2???R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBA?A?3@XZ@A"
-// MSVC2015-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?1???R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBA?A?3@XZ@A"
-// MSVC2015-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?1???R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBA?A?3@XZ@A"
+// MSVC2013-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?2???R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?3@XZ@A"
+// MSVC2013-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?2???R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?3@XZ@A"
+// MSVC2015-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?1???R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?3@XZ@A"
+// MSVC2015-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?1???R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?3@XZ@A"
 // CHECK: "\01??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z"
-// CHECK: "\01??R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBA?A?1@XZ"
+// CHECK: "\01??R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?1@XZ"
 auto ValueFromTemplateFuncionWithLocalLambda = TemplateFuncionWithLocalLambda(0);
diff --git a/clang/test/CodeGenCXX/vla-lambda-capturing.cpp b/clang/test/CodeGenCXX/vla-lambda-capturing.cpp
index 27d263b7277..f2332bf0dc9 100644
--- a/clang/test/CodeGenCXX/vla-lambda-capturing.cpp
+++ b/clang/test/CodeGenCXX/vla-lambda-capturing.cpp
@@ -22,7 +22,7 @@ typedef __INTPTR_TYPE__ intptr_t;
 // CHECK:       store [[INTPTR_T]]* %{{.+}}, [[INTPTR_T]]** [[CAP_BUFFER_ADDR]]
 // CHECK:       [[CAP_N_REF:%.+]] = getelementptr inbounds [[CAP_TYPE1]], [[CAP_TYPE1]]* [[CAP_ARG:%.+]], i{{.+}} 0, i{{.+}} 2
 // CHECK:       store [[INTPTR_T]]* [[N_ADDR]], [[INTPTR_T]]** [[CAP_N_REF]]
-// CHECK:       call void [[G_LAMBDA:@.+]]([[CAP_TYPE1]]* [[CAP_ARG]])
+// CHECK:       call{{( x86_thiscallcc)?}} void [[G_LAMBDA:@.+]]([[CAP_TYPE1]]* [[CAP_ARG]])
 // CHECK:       ret void
 void g(intptr_t n) {
   intptr_t buffer[n];
@@ -88,7 +88,7 @@ int main() {
 // CHECK: store [[INTPTR_T]] [[SIZE]], [[INTPTR_T]]* [[CAP_SIZE_REF]]
 // CHECK: [[CAP_BUFFER_ADDR_REF:%.+]] = getelementptr inbounds [[CAP_TYPE2]], [[CAP_TYPE2]]* [[CAP_ARG]], i{{.+}} 0, i{{.+}} 1
 // CHECK: store [[INTPTR_T]]* [[BUFFER_ADDR]], [[INTPTR_T]]** [[CAP_BUFFER_ADDR_REF]]
-// CHECK: call void [[F_INT_LAMBDA:@.+]]([[CAP_TYPE2]]* [[CAP_ARG]])
+// CHECK: call{{( x86_thiscallcc)?}} void [[F_INT_LAMBDA:@.+]]([[CAP_TYPE2]]* [[CAP_ARG]])
 // CHECK: call void @llvm.stackrestore(
 // CHECK: ret void
 // CHECK: void [[B_INT]]([[INTPTR_T]]
@@ -107,11 +107,11 @@ int main() {
 // CHECK: store [[INTPTR_T]]* [[BUFFER1_ADDR]], [[INTPTR_T]]** [[CAP_BUFFER1_ADDR_REF]]
 // CHECK: [[CAP_BUFFER2_ADDR_REF:%.+]] = getelementptr inbounds [[CAP_TYPE3]], [[CAP_TYPE3]]* [[CAP_ARG]], i{{.+}} 0, i{{.+}} 4
 // CHECK: store [[INTPTR_T]]* [[BUFFER2_ADDR]], [[INTPTR_T]]** [[CAP_BUFFER2_ADDR_REF]]
-// CHECK: call void [[B_INT_LAMBDA:@.+]]([[CAP_TYPE3]]* [[CAP_ARG]])
+// CHECK: call{{( x86_thiscallcc)?}} void [[B_INT_LAMBDA:@.+]]([[CAP_TYPE3]]* [[CAP_ARG]])
 // CHECK: call void @llvm.stackrestore(
 // CHECK: ret void
 
-// CHECK: define linkonce_odr void [[F_INT_LAMBDA]]([[CAP_TYPE2]]*
+// CHECK: define linkonce_odr{{( x86_thiscallcc)?}} void [[F_INT_LAMBDA]]([[CAP_TYPE2]]*
 // CHECK: [[THIS:%.+]] = load [[CAP_TYPE2]]*, [[CAP_TYPE2]]**
 // CHECK: [[SIZE_REF:%.+]] = getelementptr inbounds [[CAP_TYPE2]], [[CAP_TYPE2]]* [[THIS]], i{{.+}} 0, i{{.+}} 0
 // CHECK: [[SIZE:%.+]] = load [[INTPTR_T]], [[INTPTR_T]]* [[SIZE_REF]]
@@ -120,7 +120,7 @@ int main() {
 // CHECK: call void @llvm.stackrestore(
 // CHECK: ret void
 
-// CHECK: define {{.*}} void [[B_INT_LAMBDA]]([[CAP_TYPE3]]*
+// CHECK: define linkonce_odr{{( x86_thiscallcc)?}} void [[B_INT_LAMBDA]]([[CAP_TYPE3]]*
 // CHECK: [[SIZE2_REF:%.+]] = getelementptr inbounds [[CAP_TYPE3]], [[CAP_TYPE3]]* [[THIS:%.+]], i{{[0-9]+}} 0, i{{[0-9]+}} 1
 // CHECK: [[SIZE2:%.+]] = load i{{[0-9]+}}, i{{[0-9]+}}* [[SIZE2_REF]]
 // CHECK: [[SIZE1_REF:%.+]] = getelementptr inbounds [[CAP_TYPE3]], [[CAP_TYPE3]]* [[THIS]], i{{[0-9]+}} 0, i{{[0-9]+}} 2
@@ -152,10 +152,10 @@ int main() {
 // CHECK: [[BUFFER1_ADDR_REF_ORIG:%.+]] = getelementptr inbounds [[CAP_TYPE3]], [[CAP_TYPE3]]* [[THIS]], i{{[0-9]+}} 0, i{{[0-9]+}} 3
 // CHECK: [[BUFFER1_ADDR_ORIG:%.+]] = load [[INTPTR_T]]*, [[INTPTR_T]]** [[BUFFER1_ADDR_REF_ORIG]]
 // CHECK: store [[INTPTR_T]]* [[BUFFER1_ADDR_ORIG]], [[INTPTR_T]]** [[BUFFER1_ADDR_REF]]
-// CHECK: call void [[B_INT_LAMBDA_LAMBDA:@.+]]([[CAP_TYPE4]]* [[CAP]])
+// CHECK: call{{( x86_thiscallcc)?}} void [[B_INT_LAMBDA_LAMBDA:@.+]]([[CAP_TYPE4]]* [[CAP]])
 // CHECK: ret void
 
-// CHECK: define {{.*}} void [[B_INT_LAMBDA_LAMBDA]]([[CAP_TYPE4]]*
+// CHECK: define linkonce_odr{{( x86_thiscallcc)?}} void [[B_INT_LAMBDA_LAMBDA]]([[CAP_TYPE4]]*
 // CHECK: [[SIZE1_REF:%.+]] = getelementptr inbounds [[CAP_TYPE4]], [[CAP_TYPE4]]* [[THIS:%.+]], i{{[0-9]+}} 0, i{{[0-9]+}} 1
 // CHECK: [[SIZE1:%.+]] = load i{{[0-9]+}}, i{{[0-9]+}}* [[SIZE1_REF]]
 // CHECK: [[SIZE2_REF:%.+]] = getelementptr inbounds [[CAP_TYPE4]], [[CAP_TYPE4]]* [[THIS]], i{{[0-9]+}} 0, i{{[0-9]+}} 3
diff --git a/clang/test/OpenMP/parallel_firstprivate_codegen.cpp b/clang/test/OpenMP/parallel_firstprivate_codegen.cpp
index 7adf8e294c2..25cf2b200c3 100644
--- a/clang/test/OpenMP/parallel_firstprivate_codegen.cpp
+++ b/clang/test/OpenMP/parallel_firstprivate_codegen.cpp
@@ -52,7 +52,7 @@ int main() {
 #ifdef LAMBDA
   // LAMBDA: [[G:@.+]] = global i{{[0-9]+}} 1212,
   // LAMBDA-LABEL: @main
-  // LAMBDA: call void [[OUTER_LAMBDA:@.+]](
+  // LAMBDA: call{{( x86_thiscallcc)?}} void [[OUTER_LAMBDA:@.+]](
   [&]() {
   // LAMBDA: define{{.*}} internal{{.*}} void [[OUTER_LAMBDA]](
   // LAMBDA: [[G_LOCAL_REF:%.+]] = getelementptr inbounds %{{.+}}, %{{.+}}* [[AGG_CAPTURED:%.+]], i{{[0-9]+}} 0, i{{[0-9]+}} 0
@@ -74,7 +74,7 @@ int main() {
     // LAMBDA: store volatile i{{[0-9]+}} 1, i{{[0-9]+}}* [[G_PRIVATE_ADDR]],
     // LAMBDA: [[G_PRIVATE_ADDR_REF:%.+]] = getelementptr inbounds %{{.+}}, %{{.+}}* [[ARG:%.+]], i{{[0-9]+}} 0, i{{[0-9]+}} 0
     // LAMBDA: store i{{[0-9]+}}* [[G_PRIVATE_ADDR]], i{{[0-9]+}}** [[G_PRIVATE_ADDR_REF]]
-    // LAMBDA: call void [[INNER_LAMBDA:@.+]](%{{.+}}* [[ARG]])
+    // LAMBDA: call{{( x86_thiscallcc)?}} void [[INNER_LAMBDA:@.+]](%{{.+}}* [[ARG]])
     [&]() {
       // LAMBDA: define {{.+}} void [[INNER_LAMBDA]](%{{.+}}* [[ARG_PTR:%.+]])
       // LAMBDA: store %{{.+}}* [[ARG_PTR]], %{{.+}}** [[ARG_PTR_REF:%.+]],
diff --git a/clang/test/OpenMP/parallel_private_codegen.cpp b/clang/test/OpenMP/parallel_private_codegen.cpp
index 7094e4f1be3..cdbace94071 100644
--- a/clang/test/OpenMP/parallel_private_codegen.cpp
+++ b/clang/test/OpenMP/parallel_private_codegen.cpp
@@ -42,7 +42,7 @@ int main() {
 #ifdef LAMBDA
   // LAMBDA: [[G:@.+]] = global i{{[0-9]+}} 1212,
   // LAMBDA-LABEL: @main
-  // LAMBDA: call void [[OUTER_LAMBDA:@.+]](
+  // LAMBDA: call{{( x86_thiscallcc)?}} void [[OUTER_LAMBDA:@.+]](
   [&]() {
   // LAMBDA: define{{.*}} internal{{.*}} void [[OUTER_LAMBDA]](
   // LAMBDA: [[G_LOCAL_REF:%.+]] = getelementptr inbounds %{{.+}}, %{{.+}}* [[AGG_CAPTURED:%.+]], i{{[0-9]+}} 0, i{{[0-9]+}} 0
@@ -59,7 +59,7 @@ int main() {
     // LAMBDA: store volatile i{{[0-9]+}} 1, i{{[0-9]+}}* [[G_PRIVATE_ADDR]],
     // LAMBDA: [[G_PRIVATE_ADDR_REF:%.+]] = getelementptr inbounds %{{.+}}, %{{.+}}* [[ARG:%.+]], i{{[0-9]+}} 0, i{{[0-9]+}} 0
     // LAMBDA: store i{{[0-9]+}}* [[G_PRIVATE_ADDR]], i{{[0-9]+}}** [[G_PRIVATE_ADDR_REF]]
-    // LAMBDA: call void [[INNER_LAMBDA:@.+]](%{{.+}}* [[ARG]])
+    // LAMBDA: call{{( x86_thiscallcc)?}} void [[INNER_LAMBDA:@.+]](%{{.+}}* [[ARG]])
     [&]() {
       // LAMBDA: define {{.+}} void [[INNER_LAMBDA]](%{{.+}}* [[ARG_PTR:%.+]])
       // LAMBDA: store %{{.+}}* [[ARG_PTR]], %{{.+}}** [[ARG_PTR_REF:%.+]],
diff --git a/clang/test/Profile/cxx-lambda.cpp b/clang/test/Profile/cxx-lambda.cpp
index 6790149c7f2..34e185715ba 100644
--- a/clang/test/Profile/cxx-lambda.cpp
+++ b/clang/test/Profile/cxx-lambda.cpp
@@ -19,8 +19,8 @@
 void lambdas() {
   int i = 1;
 
-  // LMBGEN-LABEL: define internal{{( zeroext)?}} i1 @"_ZZ7lambdasvENK3$_0clEi"(
-  // LMBUSE-LABEL: define internal{{( zeroext)?}} i1 @"_ZZ7lambdasvENK3$_0clEi"(
+  // LMBGEN-LABEL: define internal{{( x86_thiscallcc)?( zeroext)?}} i1 @"_ZZ7lambdasvENK3$_0clEi"(
+  // LMBUSE-LABEL: define internal{{( x86_thiscallcc)?( zeroext)?}} i1 @"_ZZ7lambdasvENK3$_0clEi"(
   // LMBGEN: store {{.*}} @[[LFC]], i64 0, i64 0
   auto f = [&i](int k) {
     // LMBGEN: store {{.*}} @[[LFC]], i64 0, i64 1
diff --git a/clang/test/SemaCXX/decl-microsoft-call-conv.cpp b/clang/test/SemaCXX/decl-microsoft-call-conv.cpp
index a4b68cdbc7d..6c392ea9420 100644
--- a/clang/test/SemaCXX/decl-microsoft-call-conv.cpp
+++ b/clang/test/SemaCXX/decl-microsoft-call-conv.cpp
@@ -1,6 +1,6 @@
-// RUN: %clang_cc1 -triple i686-pc-win32 -fms-extensions -verify %s
-// RUN: %clang_cc1 -triple i686-pc-mingw32 -verify %s
-// RUN: %clang_cc1 -triple i686-pc-mingw32 -fms-extensions -verify %s
+// RUN: %clang_cc1 -std=c++14 -triple i686-pc-win32 -fms-extensions -verify %s
+// RUN: %clang_cc1 -std=c++14 -triple i686-pc-mingw32 -verify %s
+// RUN: %clang_cc1 -std=c++14 -triple i686-pc-mingw32 -fms-extensions -verify %s
 
 typedef void void_fun_t();
 typedef void __cdecl cdecl_fun_t();
@@ -242,3 +242,19 @@ namespace test8 {
     s.f(p); // expected-note {{in instantiation of member function 'test8::S<void *>::f' requested here}}
   }
 }
+
+namespace test9 {
+  // Used to fail when we forgot to make lambda call operators use __thiscall.
+  template <typename F>
+  decltype(auto) deduce(F f) {
+    return &decltype(f)::operator();
+  }
+  template <typename C, typename R, typename A>
+  decltype(auto) signaturehelper(R (C::*f)(A) const) {
+    return R();
+  }
+  void f() {
+    auto l = [](int x) { return x * 2; };
+    decltype(signaturehelper(deduce(l))) p;
+  }
+}