This revision was automatically updated to reflect the committed changes.
Closed by commit rL318440: [MS] Apply adjustments after storing 'this'
(authored by rnk).
Changed prior to commit:
https://reviews.llvm.org/D40109?vs=123104&id=123218#toc
Repository:
rL LLVM
https://reviews.llvm.org/D40109
Files:
cfe/trunk/lib/CodeGen/CGCXXABI.cpp
cfe/trunk/lib/CodeGen/CGCXXABI.h
cfe/trunk/lib/CodeGen/CGDecl.cpp
cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp
cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp
cfe/trunk/test/CodeGenCXX/microsoft-abi-multiple-nonvirtual-inheritance.cpp
cfe/trunk/test/CodeGenCXX/microsoft-abi-virtual-inheritance-vtordisps.cpp
cfe/trunk/test/CodeGenCXX/microsoft-abi-virtual-inheritance.cpp
cfe/trunk/test/CodeGenCXX/microsoft-abi-vtables-multiple-nonvirtual-inheritance-this-adjustment.cpp
Index: cfe/trunk/test/CodeGenCXX/microsoft-abi-virtual-inheritance-vtordisps.cpp
===================================================================
--- cfe/trunk/test/CodeGenCXX/microsoft-abi-virtual-inheritance-vtordisps.cpp
+++ cfe/trunk/test/CodeGenCXX/microsoft-abi-virtual-inheritance-vtordisps.cpp
@@ -24,6 +24,7 @@
D::D() {} // Forces vftable emission.
// CHECK-LABEL: define linkonce_odr x86_thiscallcc void @"\01?f@D@@$4PPPPPPPM@A@AEXXZ"
+// Note that the vtordisp is applied before really adjusting to D*.
// CHECK: %[[ECX:.*]] = load %struct.D*, %struct.D** %{{.*}}
// CHECK: %[[ECX_i8:.*]] = bitcast %struct.D* %[[ECX]] to i8*
// CHECK: %[[VTORDISP_PTR_i8:.*]] = getelementptr inbounds i8, i8* %[[ECX_i8]], i32 -4
Index: cfe/trunk/test/CodeGenCXX/microsoft-abi-virtual-inheritance.cpp
===================================================================
--- cfe/trunk/test/CodeGenCXX/microsoft-abi-virtual-inheritance.cpp
+++ cfe/trunk/test/CodeGenCXX/microsoft-abi-virtual-inheritance.cpp
@@ -1,9 +1,9 @@
-// RUN: %clang_cc1 %s -fno-rtti -triple=i386-pc-win32 -emit-llvm -o %t
+// RUN: %clang_cc1 %s -fno-rtti -std=c++11 -Wno-inaccessible-base -triple=i386-pc-win32 -emit-llvm -o %t
// RUN: FileCheck %s < %t
// RUN: FileCheck --check-prefix=CHECK2 %s < %t
// For now, just make sure x86_64 doesn't crash.
-// RUN: %clang_cc1 %s -fno-rtti -triple=x86_64-pc-win32 -emit-llvm -o %t
+// RUN: %clang_cc1 %s -fno-rtti -std=c++11 -Wno-inaccessible-base -triple=x86_64-pc-win32 -emit-llvm -o %t
struct VBase {
virtual ~VBase();
@@ -52,12 +52,14 @@
B::~B() {
// CHECK-LABEL: define x86_thiscallcc void @"\01??1B@@UAE@XZ"
- // Adjust the this parameter:
- // CHECK: %[[THIS_PARAM_i8:.*]] = bitcast %struct.B* {{.*}} to i8*
- // CHECK: %[[THIS_i8:.*]] = getelementptr inbounds i8, i8* %[[THIS_PARAM_i8]], i32 -8
- // CHECK: %[[THIS:.*]] = bitcast i8* %[[THIS_i8]] to %struct.B*
- // CHECK: store %struct.B* %[[THIS]], %struct.B** %[[THIS_ADDR:.*]], align 4
- // CHECK: %[[THIS:.*]] = load %struct.B*, %struct.B** %[[THIS_ADDR]]
+ // Store initial this:
+ // CHECK: %[[THIS_ADDR:.*]] = alloca %struct.B*
+ // CHECK: store %struct.B* %{{.*}}, %struct.B** %[[THIS_ADDR]], align 4
+ // Reload and adjust the this parameter:
+ // CHECK: %[[THIS_RELOAD:.*]] = load %struct.B*, %struct.B** %[[THIS_ADDR]]
+ // CHECK: %[[THIS_UNADJ_i8:.*]] = bitcast %struct.B* %[[THIS_RELOAD]] to i8*
+ // CHECK: %[[THIS_ADJ_i8:.*]] = getelementptr inbounds i8, i8* %[[THIS_UNADJ_i8]], i32 -8
+ // CHECK: %[[THIS:.*]] = bitcast i8* %[[THIS_ADJ_i8]] to %struct.B*
// Restore the vfptr that could have been changed by a subclass.
// CHECK: %[[THIS_i8:.*]] = bitcast %struct.B* %[[THIS]] to i8*
@@ -97,11 +99,11 @@
// CHECK2: ret
// CHECK2-LABEL: define linkonce_odr x86_thiscallcc i8* @"\01??_GB@@UAEPAXI@Z"
- // CHECK2: %[[THIS_PARAM_i8:.*]] = bitcast %struct.B* {{.*}} to i8*
+ // CHECK2: store %struct.B* %{{.*}}, %struct.B** %[[THIS_ADDR:.*]], align 4
+ // CHECK2: %[[THIS:.*]] = load %struct.B*, %struct.B** %[[THIS_ADDR]]
+ // CHECK2: %[[THIS_PARAM_i8:.*]] = bitcast %struct.B* %[[THIS]] to i8*
// CHECK2: %[[THIS_i8:.*]] = getelementptr inbounds i8, i8* %[[THIS_PARAM_i8:.*]], i32 -8
// CHECK2: %[[THIS:.*]] = bitcast i8* %[[THIS_i8]] to %struct.B*
- // CHECK2: store %struct.B* %[[THIS]], %struct.B** %[[THIS_ADDR:.*]], align 4
- // CHECK2: %[[THIS:.*]] = load %struct.B*, %struct.B** %[[THIS_ADDR]]
// CHECK2: call x86_thiscallcc void @"\01??_DB@@QAEXXZ"(%struct.B* %[[THIS]])
// ...
// CHECK2: ret
@@ -113,13 +115,17 @@
// B::foo gets 'this' cast to VBase* in ECX (i.e. this+8) so we
// need to adjust 'this' before use.
//
-// CHECK: %[[THIS_ADDR:.*]] = alloca %struct.B*, align 4
-// CHECK: %[[THIS_i8:.*]] = getelementptr inbounds i8, i8* %[[ECX:.*]], i32 -8
-// CHECK: %[[THIS:.*]] = bitcast i8* %[[THIS_i8]] to %struct.B*
-// CHECK: store %struct.B* %[[THIS]], %struct.B** %[[THIS_ADDR]], align 4
+// Store initial this:
+// CHECK: %[[THIS_ADDR:.*]] = alloca %struct.B*
+// CHECK: store %struct.B* %{{.*}}, %struct.B** %[[THIS_ADDR]], align 4
+//
+// Reload and adjust the this parameter:
+// CHECK: %[[THIS_RELOAD:.*]] = load %struct.B*, %struct.B** %[[THIS_ADDR]]
+// CHECK: %[[THIS_UNADJ_i8:.*]] = bitcast %struct.B* %[[THIS_RELOAD]] to i8*
+// CHECK: %[[THIS_ADJ_i8:.*]] = getelementptr inbounds i8, i8* %[[THIS_UNADJ_i8]], i32 -8
+// CHECK: %[[THIS:.*]] = bitcast i8* %[[THIS_ADJ_i8]] to %struct.B*
field = 42;
-// CHECK: %[[THIS:.*]] = load %struct.B*, %struct.B** %[[THIS_ADDR]]
// CHECK: %[[THIS8:.*]] = bitcast %struct.B* %[[THIS]] to i8*
// CHECK: %[[VBPTR:.*]] = getelementptr inbounds i8, i8* %[[THIS8]], i32 0
// CHECK: %[[VBPTR8:.*]] = bitcast i8* %[[VBPTR]] to i32**
@@ -284,11 +290,16 @@
D::~D() {
// CHECK-LABEL: define x86_thiscallcc void @"\01??1D@diamond@@UAE@XZ"(%"struct.diamond::D"*{{.*}})
- // CHECK: %[[ARG_i8:.*]] = bitcast %"struct.diamond::D"* %{{.*}} to i8*
- // CHECK: %[[THIS_i8:.*]] = getelementptr inbounds i8, i8* %[[ARG_i8]], i32 -24
- // CHECK: %[[THIS:.*]] = bitcast i8* %[[THIS_i8]] to %"struct.diamond::D"*
- // CHECK: store %"struct.diamond::D"* %[[THIS]], %"struct.diamond::D"** %[[THIS_VAL:.*]], align 4
- // CHECK: %[[THIS:.*]] = load %"struct.diamond::D"*, %"struct.diamond::D"** %[[THIS_VAL]]
+ // Store initial this:
+ // CHECK: %[[THIS_ADDR:.*]] = alloca %"struct.diamond::D"*
+ // CHECK: store %"struct.diamond::D"* %{{.*}}, %"struct.diamond::D"** %[[THIS_ADDR]], align 4
+ //
+ // Reload and adjust the this parameter:
+ // CHECK: %[[THIS_RELOAD:.*]] = load %"struct.diamond::D"*, %"struct.diamond::D"** %[[THIS_ADDR]]
+ // CHECK: %[[THIS_UNADJ_i8:.*]] = bitcast %"struct.diamond::D"* %[[THIS_RELOAD]] to i8*
+ // CHECK: %[[THIS_ADJ_i8:.*]] = getelementptr inbounds i8, i8* %[[THIS_UNADJ_i8]], i32 -24
+ // CHECK: %[[THIS:.*]] = bitcast i8* %[[THIS_ADJ_i8]] to %"struct.diamond::D"*
+ //
// CHECK: %[[D_i8:.*]] = bitcast %"struct.diamond::D"* %[[THIS]] to i8*
// CHECK: %[[C_i8:.*]] = getelementptr inbounds i8, i8* %[[D_i8]], i32 4
// CHECK: %[[C:.*]] = bitcast i8* %[[C_i8]] to %"struct.diamond::C"*
Index: cfe/trunk/test/CodeGenCXX/microsoft-abi-multiple-nonvirtual-inheritance.cpp
===================================================================
--- cfe/trunk/test/CodeGenCXX/microsoft-abi-multiple-nonvirtual-inheritance.cpp
+++ cfe/trunk/test/CodeGenCXX/microsoft-abi-multiple-nonvirtual-inheritance.cpp
@@ -19,7 +19,7 @@
extern "C" void foo(void *);
void call_left_no_override(ChildNoOverride *child) {
-// CHECK: define void @"\01?call_left_no_override
+// CHECK-LABEL: define void @"\01?call_left_no_override
// CHECK: %[[CHILD:.*]] = load %struct.ChildNoOverride
child->left();
@@ -34,7 +34,8 @@
}
void ChildOverride::left() {
-// CHECK: define x86_thiscallcc void @"\01?left@ChildOverride@@UAEXXZ"(%struct.ChildOverride* %[[THIS:.*]])
+// CHECK-LABEL: define x86_thiscallcc void @"\01?left@ChildOverride@@UAEXXZ"
+// CHECK-SAME: (%struct.ChildOverride* %[[THIS:.*]])
//
// No need to adjust 'this' as the ChildOverride's layout begins with Left.
// CHECK: %[[THIS_ADDR:.*]] = alloca %struct.ChildOverride*, align 4
@@ -48,7 +49,7 @@
}
void call_left_override(ChildOverride *child) {
-// CHECK: define void @"\01?call_left_override
+// CHECK-LABEL: define void @"\01?call_left_override
// CHECK: %[[CHILD:.*]] = load %struct.ChildOverride
child->left();
@@ -62,7 +63,7 @@
}
void call_right_no_override(ChildNoOverride *child) {
-// CHECK: define void @"\01?call_right_no_override
+// CHECK-LABEL: define void @"\01?call_right_no_override
// CHECK: %[[CHILD:.*]] = load %struct.ChildNoOverride
child->right();
@@ -82,25 +83,27 @@
}
void ChildOverride::right() {
-// CHECK: define x86_thiscallcc void @"\01?right@ChildOverride@@UAEXXZ"(i8*
+// CHECK-LABEL: define x86_thiscallcc void @"\01?right@ChildOverride@@UAEXXZ"(i8*
//
// ChildOverride::right gets 'this' cast to Right* in ECX (i.e. this+4) so we
// need to adjust 'this' before use.
//
// CHECK: %[[THIS_ADDR:.*]] = alloca %struct.ChildOverride*, align 4
-// CHECK: %[[THIS_i8:.*]] = getelementptr inbounds i8, i8* %[[ECX:.*]], i32 -4
-// CHECK: %[[THIS:.*]] = bitcast i8* %[[THIS_i8]] to %struct.ChildOverride*
-// CHECK: store %struct.ChildOverride* %[[THIS]], %struct.ChildOverride** %[[THIS_ADDR]], align 4
+// CHECK: %[[THIS_INIT:.*]] = bitcast i8* %[[ECX:.*]] to %struct.ChildOverride*
+// CHECK: store %struct.ChildOverride* %[[THIS_INIT]], %struct.ChildOverride** %[[THIS_ADDR]], align 4
+// CHECK: %[[THIS_RELOAD:.*]] = load %struct.ChildOverride*, %struct.ChildOverride** %[[THIS_ADDR]]
+// CHECK: %[[THIS_i8:.*]] = bitcast %struct.ChildOverride* %[[THIS_RELOAD]] to i8*
+// CHECK: %[[THIS_ADJUSTED:.*]] = getelementptr inbounds i8, i8* %[[THIS_i8]], i32 -4
+// CHECK: %[[THIS:.*]] = bitcast i8* %[[THIS_ADJUSTED]] to %struct.ChildOverride*
foo(this);
-// CHECK: %[[THIS:.*]] = load %struct.ChildOverride*, %struct.ChildOverride** %[[THIS_ADDR]]
// CHECK: %[[THIS_PARAM:.*]] = bitcast %struct.ChildOverride* %[[THIS]] to i8*
// CHECK: call void @foo(i8* %[[THIS_PARAM]])
// CHECK: ret
}
void call_right_override(ChildOverride *child) {
-// CHECK: define void @"\01?call_right_override
+// CHECK-LABEL: define void @"\01?call_right_override
// CHECK: %[[CHILD:.*]] = load %struct.ChildOverride
child->right();
@@ -127,15 +130,17 @@
};
void GrandchildOverride::right() {
-// CHECK: define x86_thiscallcc void @"\01?right@GrandchildOverride@@UAEXXZ"(i8*
+// CHECK-LABEL: define x86_thiscallcc void @"\01?right@GrandchildOverride@@UAEXXZ"(i8*
//
// CHECK: %[[THIS_ADDR:.*]] = alloca %struct.GrandchildOverride*, align 4
-// CHECK: %[[THIS_i8:.*]] = getelementptr inbounds i8, i8* %[[ECX:.*]], i32 -4
-// CHECK: %[[THIS:.*]] = bitcast i8* %[[THIS_i8]] to %struct.GrandchildOverride*
-// CHECK: store %struct.GrandchildOverride* %[[THIS]], %struct.GrandchildOverride** %[[THIS_ADDR]], align 4
+// CHECK: %[[THIS_INIT:.*]] = bitcast i8* %[[ECX:.*]] to %struct.GrandchildOverride*
+// CHECK: store %struct.GrandchildOverride* %[[THIS_INIT]], %struct.GrandchildOverride** %[[THIS_ADDR]], align 4
+// CHECK: %[[THIS_RELOAD:.*]] = load %struct.GrandchildOverride*, %struct.GrandchildOverride** %[[THIS_ADDR]]
+// CHECK: %[[THIS_i8:.*]] = bitcast %struct.GrandchildOverride* %[[THIS_RELOAD]] to i8*
+// CHECK: %[[THIS_ADJUSTED:.*]] = getelementptr inbounds i8, i8* %[[THIS_i8]], i32 -4
+// CHECK: %[[THIS:.*]] = bitcast i8* %[[THIS_ADJUSTED]] to %struct.GrandchildOverride*
foo(this);
-// CHECK: %[[THIS:.*]] = load %struct.GrandchildOverride*, %struct.GrandchildOverride** %[[THIS_ADDR]]
// CHECK: %[[THIS_PARAM:.*]] = bitcast %struct.GrandchildOverride* %[[THIS]] to i8*
// CHECK: call void @foo(i8* %[[THIS_PARAM]])
// CHECK: ret
@@ -148,19 +153,19 @@
void emit_ctors() {
Left l;
- // CHECK: define {{.*}} @"\01??0Left@@QAE@XZ"
+ // CHECK-LABEL: define {{.*}} @"\01??0Left@@QAE@XZ"
// CHECK-NOT: getelementptr
// CHECK: store i32 (...)** bitcast ({ [1 x i8*] }* @"\01??_7Left@@6B@" to i32 (...)**)
// CHECK: ret
Right r;
- // CHECK: define {{.*}} @"\01??0Right@@QAE@XZ"
+ // CHECK-LABEL: define {{.*}} @"\01??0Right@@QAE@XZ"
// CHECK-NOT: getelementptr
// CHECK: store i32 (...)** bitcast ({ [1 x i8*] }* @"\01??_7Right@@6B@" to i32 (...)**)
// CHECK: ret
ChildOverride co;
- // CHECK: define {{.*}} @"\01??0ChildOverride@@QAE@XZ"
+ // CHECK-LABEL: define {{.*}} @"\01??0ChildOverride@@QAE@XZ"
// CHECK: %[[THIS:.*]] = load %struct.ChildOverride*, %struct.ChildOverride**
// CHECK: %[[VFPTR:.*]] = bitcast %struct.ChildOverride* %[[THIS]] to i32 (...)***
// CHECK: store i32 (...)** bitcast ({ [1 x i8*] }* @"\01??_7ChildOverride@@6BLeft@@@" to i32 (...)**), i32 (...)*** %[[VFPTR]]
@@ -171,7 +176,7 @@
// CHECK: ret
GrandchildOverride gc;
- // CHECK: define {{.*}} @"\01??0GrandchildOverride@@QAE@XZ"
+ // CHECK-LABEL: define {{.*}} @"\01??0GrandchildOverride@@QAE@XZ"
// CHECK: %[[THIS:.*]] = load %struct.GrandchildOverride*, %struct.GrandchildOverride**
// CHECK: %[[VFPTR:.*]] = bitcast %struct.GrandchildOverride* %[[THIS]] to i32 (...)***
// CHECK: store i32 (...)** bitcast ({ [1 x i8*] }* @"\01??_7GrandchildOverride@@6BLeft@@@" to i32 (...)**), i32 (...)*** %[[VFPTR]]
Index: cfe/trunk/test/CodeGenCXX/microsoft-abi-vtables-multiple-nonvirtual-inheritance-this-adjustment.cpp
===================================================================
--- cfe/trunk/test/CodeGenCXX/microsoft-abi-vtables-multiple-nonvirtual-inheritance-this-adjustment.cpp
+++ cfe/trunk/test/CodeGenCXX/microsoft-abi-vtables-multiple-nonvirtual-inheritance-this-adjustment.cpp
@@ -196,7 +196,11 @@
}
// BITCODE-LABEL: define void @"\01?g@C@pr30293@@UAAXUNonTrivial@2@@Z"(<{ i8*, %"struct.pr30293::NonTrivial" }>* inalloca)
-// BITCODE: %[[this1:[^ ]*]] = load i8*, i8** %[[thisaddr:[^ ]*]], align 4
-// BITCODE-NEXT: %[[this2:[^ ]*]] = getelementptr inbounds i8, i8* %[[this1]], i32 -4
-// BITCODE-NEXT: store i8* %[[this2]], i8** %[[thisaddr]], align 4
+// BITCODE: %[[thisaddr:[^ ]*]] = getelementptr inbounds <{ i8*, %"struct.pr30293::NonTrivial" }>, <{ i8*, %"struct.pr30293::NonTrivial" }>* {{.*}}, i32 0, i32 0
+// BITCODE: %[[thisaddr1:[^ ]*]] = bitcast i8** %[[thisaddr]] to %"struct.pr30293::C"**
+// BITCODE: %[[this1:[^ ]*]] = load %"struct.pr30293::C"*, %"struct.pr30293::C"** %[[thisaddr1]], align 4
+// BITCODE: %[[this2:[^ ]*]] = bitcast %"struct.pr30293::C"* %[[this1]] to i8*
+// BITCODE: %[[this3:[^ ]*]] = getelementptr inbounds i8, i8* %[[this2]], i32 -4
+// BITCODE: %[[this4:[^ ]*]] = bitcast i8* %[[this3]] to %"struct.pr30293::C"*
+// BITCODE: store %"struct.pr30293::C"* %[[this4]], %"struct.pr30293::C"** @"\01?whatsthis@pr30293@@3PAUC@1@A", align 4
}
Index: cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp
===================================================================
--- cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp
+++ cfe/trunk/lib/CodeGen/ItaniumCXXABI.cpp
@@ -1443,8 +1443,9 @@
if (CGF.CurFuncDecl && CGF.CurFuncDecl->hasAttr<NakedAttr>())
return;
- /// Initialize the 'this' slot.
- EmitThisParam(CGF);
+ /// Initialize the 'this' slot. In the Itanium C++ ABI, no prologue
+ /// adjustments are required, becuase they are all handled by thunks.
+ setCXXABIThisValue(CGF, loadIncomingCXXThis(CGF));
/// Initialize the 'vtt' slot if needed.
if (getStructorImplicitParamDecl(CGF)) {
Index: cfe/trunk/lib/CodeGen/CGCXXABI.h
===================================================================
--- cfe/trunk/lib/CodeGen/CGCXXABI.h
+++ cfe/trunk/lib/CodeGen/CGCXXABI.h
@@ -73,9 +73,10 @@
return CGF.CXXStructorImplicitParamValue;
}
- /// Perform prolog initialization of the parameter variable suitable
- /// for 'this' emitted by buildThisParam.
- void EmitThisParam(CodeGenFunction &CGF);
+ /// Loads the incoming C++ this pointer as it was passed by the caller.
+ llvm::Value *loadIncomingCXXThis(CodeGenFunction &CGF);
+
+ void setCXXABIThisValue(CodeGenFunction &CGF, llvm::Value *ThisPtr);
ASTContext &getContext() const { return CGM.getContext(); }
@@ -358,13 +359,6 @@
return CharUnits::Zero();
}
- /// Perform ABI-specific "this" parameter adjustment in a virtual function
- /// prologue.
- virtual llvm::Value *adjustThisParameterInVirtualFunctionPrologue(
- CodeGenFunction &CGF, GlobalDecl GD, llvm::Value *This) {
- return This;
- }
-
/// Emit the ABI-specific prolog for the function.
virtual void EmitInstanceFunctionProlog(CodeGenFunction &CGF) = 0;
Index: cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp
===================================================================
--- cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp
+++ cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp
@@ -244,9 +244,6 @@
void addImplicitStructorParams(CodeGenFunction &CGF, QualType &ResTy,
FunctionArgList &Params) override;
- llvm::Value *adjustThisParameterInVirtualFunctionPrologue(
- CodeGenFunction &CGF, GlobalDecl GD, llvm::Value *This) override;
-
void EmitInstanceFunctionProlog(CodeGenFunction &CGF) override;
AddedStructorArgs
@@ -1433,50 +1430,54 @@
}
}
-llvm::Value *MicrosoftCXXABI::adjustThisParameterInVirtualFunctionPrologue(
- CodeGenFunction &CGF, GlobalDecl GD, llvm::Value *This) {
- // In this ABI, every virtual function takes a pointer to one of the
- // subobjects that first defines it as the 'this' parameter, rather than a
- // pointer to the final overrider subobject. Thus, we need to adjust it back
- // to the final overrider subobject before use.
- // See comments in the MicrosoftVFTableContext implementation for the details.
- CharUnits Adjustment = getVirtualFunctionPrologueThisAdjustment(GD);
- if (Adjustment.isZero())
- return This;
-
- unsigned AS = cast<llvm::PointerType>(This->getType())->getAddressSpace();
- llvm::Type *charPtrTy = CGF.Int8Ty->getPointerTo(AS),
- *thisTy = This->getType();
-
- This = CGF.Builder.CreateBitCast(This, charPtrTy);
- assert(Adjustment.isPositive());
- This = CGF.Builder.CreateConstInBoundsGEP1_32(CGF.Int8Ty, This,
- -Adjustment.getQuantity());
- return CGF.Builder.CreateBitCast(This, thisTy);
-}
-
void MicrosoftCXXABI::EmitInstanceFunctionProlog(CodeGenFunction &CGF) {
// Naked functions have no prolog.
if (CGF.CurFuncDecl && CGF.CurFuncDecl->hasAttr<NakedAttr>())
return;
- EmitThisParam(CGF);
+ // Overridden virtual methods of non-primary bases need to adjust the incoming
+ // 'this' pointer in the prologue. In this hierarchy, C::b will subtract
+ // sizeof(void*) to adjust from B* to C*:
+ // struct A { virtual void a(); };
+ // struct B { virtual void b(); };
+ // struct C : A, B { virtual void b(); };
+ //
+ // Leave the value stored in the 'this' alloca unadjusted, so that the
+ // debugger sees the unadjusted value. Microsoft debuggers require this, and
+ // will apply the ThisAdjustment in the method type information.
+ // FIXME: Do something better for DWARF debuggers, which won't expect this,
+ // without making our codegen depend on debug info settings.
+ llvm::Value *This = loadIncomingCXXThis(CGF);
+ const CXXMethodDecl *MD = cast<CXXMethodDecl>(CGF.CurGD.getDecl());
+ if (!CGF.CurFuncIsThunk && MD->isVirtual()) {
+ CharUnits Adjustment = getVirtualFunctionPrologueThisAdjustment(CGF.CurGD);
+ if (!Adjustment.isZero()) {
+ unsigned AS = cast<llvm::PointerType>(This->getType())->getAddressSpace();
+ llvm::Type *charPtrTy = CGF.Int8Ty->getPointerTo(AS),
+ *thisTy = This->getType();
+ This = CGF.Builder.CreateBitCast(This, charPtrTy);
+ assert(Adjustment.isPositive());
+ This = CGF.Builder.CreateConstInBoundsGEP1_32(CGF.Int8Ty, This,
+ -Adjustment.getQuantity());
+ This = CGF.Builder.CreateBitCast(This, thisTy, "this.adjusted");
+ }
+ }
+ setCXXABIThisValue(CGF, This);
- /// If this is a function that the ABI specifies returns 'this', initialize
- /// the return slot to 'this' at the start of the function.
- ///
- /// Unlike the setting of return types, this is done within the ABI
- /// implementation instead of by clients of CGCXXABI because:
- /// 1) getThisValue is currently protected
- /// 2) in theory, an ABI could implement 'this' returns some other way;
- /// HasThisReturn only specifies a contract, not the implementation
+ // If this is a function that the ABI specifies returns 'this', initialize
+ // the return slot to 'this' at the start of the function.
+ //
+ // Unlike the setting of return types, this is done within the ABI
+ // implementation instead of by clients of CGCXXABI because:
+ // 1) getThisValue is currently protected
+ // 2) in theory, an ABI could implement 'this' returns some other way;
+ // HasThisReturn only specifies a contract, not the implementation
if (HasThisReturn(CGF.CurGD))
CGF.Builder.CreateStore(getThisValue(CGF), CGF.ReturnValue);
else if (hasMostDerivedReturn(CGF.CurGD))
CGF.Builder.CreateStore(CGF.EmitCastToVoidPtr(getThisValue(CGF)),
CGF.ReturnValue);
- const CXXMethodDecl *MD = cast<CXXMethodDecl>(CGF.CurGD.getDecl());
if (isa<CXXConstructorDecl>(MD) && MD->getParent()->getNumVBases()) {
assert(getStructorImplicitParamDecl(CGF) &&
"no implicit parameter for a constructor with virtual bases?");
@@ -1961,7 +1962,7 @@
// Start defining the function.
CGF.StartFunction(GlobalDecl(), FnInfo.getReturnType(), ThunkFn, FnInfo,
FunctionArgs, MD->getLocation(), SourceLocation());
- EmitThisParam(CGF);
+ setCXXABIThisValue(CGF, loadIncomingCXXThis(CGF));
// Load the vfptr and then callee from the vftable. The callee should have
// adjusted 'this' so that the vfptr is at offset zero.
@@ -3900,7 +3901,7 @@
FunctionArgs, CD->getLocation(), SourceLocation());
// Create a scope with an artificial location for the body of this function.
auto AL = ApplyDebugLocation::CreateArtificial(CGF);
- EmitThisParam(CGF);
+ setCXXABIThisValue(CGF, loadIncomingCXXThis(CGF));
llvm::Value *This = getThisValue(CGF);
llvm::Value *SrcVal =
Index: cfe/trunk/lib/CodeGen/CGCXXABI.cpp
===================================================================
--- cfe/trunk/lib/CodeGen/CGCXXABI.cpp
+++ cfe/trunk/lib/CodeGen/CGCXXABI.cpp
@@ -149,12 +149,15 @@
}
}
-void CGCXXABI::EmitThisParam(CodeGenFunction &CGF) {
+llvm::Value *CGCXXABI::loadIncomingCXXThis(CodeGenFunction &CGF) {
+ return CGF.Builder.CreateLoad(CGF.GetAddrOfLocalVar(getThisDecl(CGF)),
+ "this");
+}
+
+void CGCXXABI::setCXXABIThisValue(CodeGenFunction &CGF, llvm::Value *ThisPtr) {
/// Initialize the 'this' slot.
assert(getThisDecl(CGF) && "no 'this' variable for function");
- CGF.CXXABIThisValue
- = CGF.Builder.CreateLoad(CGF.GetAddrOfLocalVar(getThisDecl(CGF)),
- "this");
+ CGF.CXXABIThisValue = ThisPtr;
}
void CGCXXABI::EmitReturnFromThunk(CodeGenFunction &CGF,
Index: cfe/trunk/lib/CodeGen/CGDecl.cpp
===================================================================
--- cfe/trunk/lib/CodeGen/CGDecl.cpp
+++ cfe/trunk/lib/CodeGen/CGDecl.cpp
@@ -1796,24 +1796,6 @@
setBlockContextParameter(IPD, ArgNo, Arg.getDirectValue());
return;
}
-
- // Apply any prologue 'this' adjustments required by the ABI. Be careful to
- // handle the case where 'this' is passed indirectly as part of an inalloca
- // struct.
- if (const CXXMethodDecl *MD =
- dyn_cast_or_null<CXXMethodDecl>(CurCodeDecl)) {
- if (MD->isVirtual() && IPD == CXXABIThisDecl) {
- llvm::Value *This = Arg.isIndirect()
- ? Builder.CreateLoad(Arg.getIndirectAddress())
- : Arg.getDirectValue();
- This = CGM.getCXXABI().adjustThisParameterInVirtualFunctionPrologue(
- *this, CurGD, This);
- if (Arg.isIndirect())
- Builder.CreateStore(This, Arg.getIndirectAddress());
- else
- Arg = ParamValue::forDirect(This);
- }
- }
}
Address DeclPtr = Address::invalid();
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
