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[CIR] Use cir.get_vptr to initialize vptr members #1784

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[CIR] Use cir.get_vptr to initialize vptr members #1784

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15 changes: 6 additions & 9 deletions clang/lib/CIR/CodeGen/CIRGenClass.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -795,24 +795,21 @@ void CIRGenFunction::initializeVTablePointer(mlir::Location loc,
}

// Apply the offsets.
Address VTableField = LoadCXXThisAddress();
Address ClassAddr = LoadCXXThisAddress();
if (!NonVirtualOffset.isZero() || VirtualOffset) {
VTableField = ApplyNonVirtualAndVirtualOffset(
loc, *this, VTableField, NonVirtualOffset, VirtualOffset,
ClassAddr = ApplyNonVirtualAndVirtualOffset(
loc, *this, ClassAddr, NonVirtualOffset, VirtualOffset,
Vptr.VTableClass, Vptr.NearestVBase, BaseValueTy);
}

// Finally, store the address point. Use the same CIR types as the field.
//
// vtable field is derived from `this` pointer, therefore they should be in
// the same addr space.
// TODO(cir): We should be using cir.get_vptr rather than a bitcast to get
// the vptr field, but the call to ApplyNonVirtualAndVirtualOffset
// will also need to be adjusted. That should probably be using
// cir.base_class_addr.
assert(!cir::MissingFeatures::addressSpace());
VTableField = builder.createElementBitCast(loc, VTableField,
VTableAddressPoint.getType());
auto VTablePtr = builder.create<cir::VTableGetVPtrOp>(
loc, builder.getPtrToVPtrType(), ClassAddr.getPointer());
Address VTableField = Address(VTablePtr, ClassAddr.getAlignment());
auto storeOp = builder.createStore(loc, VTableAddressPoint, VTableField);
TBAAAccessInfo TBAAInfo =
CGM.getTBAAVTablePtrAccessInfo(VTableAddressPoint.getType());
Expand Down
3 changes: 2 additions & 1 deletion clang/lib/CIR/CodeGen/CIRGenItaniumCXXABI.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -992,7 +992,8 @@ mlir::Value CIRGenItaniumCXXABI::getVTableAddressPointInStructorWithVTT(
VTTPtr = CGF.getBuilder().createVTTAddrPoint(Loc, VTTPtr.getType(), VTTPtr,
VirtualPointerIndex);
// And load the address point from the VTT.
return CGF.getBuilder().createAlignedLoad(Loc, CGF.VoidPtrTy, VTTPtr,
auto VPtrType = cir::VPtrType::get(CGF.getBuilder().getContext());
return CGF.getBuilder().createAlignedLoad(Loc, VPtrType, VTTPtr,
CGF.getPointerAlign());
}

Expand Down
6 changes: 3 additions & 3 deletions clang/test/CIR/CodeGen/multi-vtable.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -40,7 +40,7 @@ int main() {

// CIR: cir.func linkonce_odr @_ZN6MotherC2Ev(%arg0: !cir.ptr<!rec_Mother>
// CIR: %{{[0-9]+}} = cir.vtable.address_point(@_ZTV6Mother, address_point = <index = 0, offset = 2>) : !cir.vptr
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!rec_Mother>), !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.vtable.get_vptr %{{[0-9]+}} : !cir.ptr<!rec_Mother> -> !cir.ptr<!cir.vptr>
// CIR: cir.store{{.*}} %2, %{{[0-9]+}} : !cir.vptr, !cir.ptr<!cir.vptr>
// CIR: cir.return
// CIR: }
Expand All @@ -53,11 +53,11 @@ int main() {

// CIR: cir.func linkonce_odr @_ZN5ChildC2Ev(%arg0: !cir.ptr<!rec_Child>
// CIR: %{{[0-9]+}} = cir.vtable.address_point(@_ZTV5Child, address_point = <index = 0, offset = 2>) : !cir.vptr
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!rec_Child>), !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.vtable.get_vptr %1 : !cir.ptr<!rec_Child> -> !cir.ptr<!cir.vptr>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.vptr, !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.vtable.address_point(@_ZTV5Child, address_point = <index = 1, offset = 2>) : !cir.vptr
// CIR: %7 = cir.base_class_addr %1 : !cir.ptr<!rec_Child> nonnull [8] -> !cir.ptr<!rec_Father>
// CIR: %8 = cir.cast(bitcast, %7 : !cir.ptr<!rec_Father>), !cir.ptr<!cir.vptr>
// CIR: %8 = cir.vtable.get_vptr %7 : !cir.ptr<!rec_Father> -> !cir.ptr<!cir.vptr>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.vptr, !cir.ptr<!cir.vptr>
// CIR: cir.return
// CIR: }
Expand Down
4 changes: 2 additions & 2 deletions clang/test/CIR/CodeGen/vtable-rtti.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -46,7 +46,7 @@ class B : public A
// CHECK: %2 = cir.base_class_addr %1 : !cir.ptr<![[ClassB]]> nonnull [0] -> !cir.ptr<![[ClassA]]>
// CHECK: cir.call @_ZN1AC2Ev(%2) : (!cir.ptr<![[ClassA]]>) -> ()
// CHECK: %3 = cir.vtable.address_point(@_ZTV1B, address_point = <index = 0, offset = 2>) : !cir.vptr
// CHECK: %4 = cir.cast(bitcast, %1 : !cir.ptr<![[ClassB]]>), !cir.ptr<!cir.vptr>
// CHECK: %4 = cir.vtable.get_vptr %1 : !cir.ptr<!rec_B> -> !cir.ptr<!cir.vptr>
// CHECK: cir.store{{.*}} %3, %4 : !cir.vptr, !cir.ptr<!cir.vptr>
// CHECK: cir.return
// CHECK: }
Expand Down Expand Up @@ -74,7 +74,7 @@ class B : public A
// CHECK: cir.store{{.*}} %arg0, %0 : !cir.ptr<![[ClassA]]>, !cir.ptr<!cir.ptr<![[ClassA]]>>
// CHECK: %1 = cir.load %0 : !cir.ptr<!cir.ptr<![[ClassA]]>>, !cir.ptr<![[ClassA]]>
// CHECK: %2 = cir.vtable.address_point(@_ZTV1A, address_point = <index = 0, offset = 2>) : !cir.vptr
// CHECK: %3 = cir.cast(bitcast, %1 : !cir.ptr<![[ClassA]]>), !cir.ptr<!cir.vptr>
// CHECK: %3 = cir.vtable.get_vptr %1 : !cir.ptr<!rec_A> -> !cir.ptr<!cir.vptr>
// CHECK: cir.store{{.*}} %2, %3 : !cir.vptr, !cir.ptr<!cir.vptr>
// CHECK: cir.return
// CHECK: }
Expand Down
37 changes: 21 additions & 16 deletions clang/test/CIR/CodeGen/vtt.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -39,7 +39,7 @@ int f() {
// Class A constructor
// CIR: cir.func linkonce_odr @_ZN1AC2Ev(%arg0: !cir.ptr<!rec_A>
// CIR: %{{[0-9]+}} = cir.vtable.address_point(@_ZTV1A, address_point = <index = 0, offset = 2>) : !cir.vptr
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!rec_A>), !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.vtable.get_vptr %{{.*}} : !cir.ptr<!rec_A> -> !cir.ptr<!cir.vptr>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.vptr, !cir.ptr<!cir.vptr>
// CIR: }

Expand All @@ -51,12 +51,14 @@ int f() {
// Class B constructor
// CIR: cir.func linkonce_odr @_ZN1BC2Ev(%arg0: !cir.ptr<!rec_B>
// CIR: %{{[0-9]+}} = cir.vtt.address_point %{{[0-9]+}} : !cir.ptr<!cir.ptr<!void>>, offset = 0 -> !cir.ptr<!cir.ptr<!void>>
// CIR: %{{[0-9]+}} = cir.load align(8) %{{[0-9]+}} : !cir.ptr<!cir.ptr<!void>>, !cir.ptr<!void>
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!rec_B>), !cir.ptr<!cir.ptr<!void>>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.ptr<!void>, !cir.ptr<!cir.ptr<!void>>
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!cir.ptr<!void>>), !cir.ptr<!cir.vptr>
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Ideally, cir.vtt.address_point would return !cir.ptr<!cir.vptr> but that introduces a problem with creating the argument list for constructors that require a VTT parameter. We're using QualType extensively in the argument list handling, and there is no QualType that corresponds to !cir.vptr. We use 'pointer-to-pointer-to-void', which is a close equivalent.

I think I can update cir.vtt.address_point and just insert bitcasts when it's used as an argument, but until then, it's 'pointer-to-pointer-to-void'.

// CIR: %{{[0-9]+}} = cir.load align(8) %{{[0-9]+}} : !cir.ptr<!cir.vptr>, !cir.vptr
// CIR: %{{[0-9]+}} = cir.vtable.get_vptr %{{[0-9]+}} : !cir.ptr<!rec_B> -> !cir.ptr<!cir.vptr>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.vptr, !cir.ptr<!cir.vptr>

// CIR: %{{[0-9]+}} = cir.vtt.address_point %{{[0-9]+}} : !cir.ptr<!cir.ptr<!void>>, offset = 1 -> !cir.ptr<!cir.ptr<!void>>
// CIR: %{{[0-9]+}} = cir.load align(8) %{{[0-9]+}} : !cir.ptr<!cir.ptr<!void>>, !cir.ptr<!void>
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!cir.ptr<!void>>), !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.load align(8) %{{[0-9]+}} : !cir.ptr<!cir.vptr>, !cir.vptr
// CIR: %{{[0-9]+}} = cir.vtable.get_vptr %{{.*}} : !cir.ptr<!rec_B> -> !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.load{{.*}} %{{[0-9]+}} : !cir.ptr<!cir.vptr>, !cir.vptr
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.vptr), !cir.ptr<!u8i>
Expand All @@ -65,8 +67,8 @@ int f() {
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!u8i>), !cir.ptr<!s64i>
// CIR: %{{[0-9]+}} = cir.load{{.*}} %{{[0-9]+}} : !cir.ptr<!s64i>, !s64i
// CIR: %{{[0-9]+}} = cir.ptr_stride(%{{[0-9]+}} : !cir.ptr<!u8i>, %{{[0-9]+}} : !s64i), !cir.ptr<!u8i>
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!rec_B>), !cir.ptr<!cir.ptr<!void>>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.ptr<!void>, !cir.ptr<!cir.ptr<!void>>
// CIR: %{{[0-9]+}} = cir.vtable.get_vptr %{{[0-9]+}} : !cir.ptr<!rec_B> -> !cir.ptr<!cir.vptr>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.vptr, !cir.ptr<!cir.vptr>
// CIR: }

// LLVM-LABEL: @_ZN1BC2Ev
Expand All @@ -83,12 +85,14 @@ int f() {
// Class C constructor
// CIR: cir.func linkonce_odr @_ZN1CC2Ev(%arg0: !cir.ptr<!rec_C>
// CIR: %{{[0-9]+}} = cir.vtt.address_point %{{[0-9]+}} : !cir.ptr<!cir.ptr<!void>>, offset = 0 -> !cir.ptr<!cir.ptr<!void>>
// CIR: %{{[0-9]+}} = cir.load align(8) %{{[0-9]+}} : !cir.ptr<!cir.ptr<!void>>, !cir.ptr<!void>
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!rec_C>), !cir.ptr<!cir.ptr<!void>>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.ptr<!void>, !cir.ptr<!cir.ptr<!void>>
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!cir.ptr<!void>>), !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.load align(8) %{{[0-9]+}} : !cir.ptr<!cir.vptr>, !cir.vptr
// CIR: %{{[0-9]+}} = cir.vtable.get_vptr %{{[0-9]+}} : !cir.ptr<!rec_C> -> !cir.ptr<!cir.vptr>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.vptr, !cir.ptr<!cir.vptr>

// CIR: %{{[0-9]+}} = cir.vtt.address_point %{{[0-9]+}} : !cir.ptr<!cir.ptr<!void>>, offset = 1 -> !cir.ptr<!cir.ptr<!void>>
// CIR: %{{[0-9]+}} = cir.load align(8) %{{[0-9]+}} : !cir.ptr<!cir.ptr<!void>>, !cir.ptr<!void>
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!cir.ptr<!void>>), !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.load align(8) %{{[0-9]+}} : !cir.ptr<!cir.vptr>, !cir.vptr
// CIR: %{{[0-9]+}} = cir.vtable.get_vptr %{{[0-9]+}} : !cir.ptr<!rec_C> -> !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.load{{.*}} %{{[0-9]+}} : !cir.ptr<!cir.vptr>, !cir.vptr
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.vptr), !cir.ptr<!u8i>
Expand All @@ -97,8 +101,9 @@ int f() {
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!u8i>), !cir.ptr<!s64i>
// CIR: %{{[0-9]+}} = cir.load{{.*}} %{{[0-9]+}} : !cir.ptr<!s64i>, !s64i
// CIR: %{{[0-9]+}} = cir.ptr_stride(%{{[0-9]+}} : !cir.ptr<!u8i>, %{{[0-9]+}} : !s64i), !cir.ptr<!u8i>
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!rec_C>), !cir.ptr<!cir.ptr<!void>>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.ptr<!void>, !cir.ptr<!cir.ptr<!void>>
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!u8i>), !cir.ptr<!rec_C>
// CIR: %{{[0-9]+}} = cir.vtable.get_vptr %{{[0-9]+}} : !cir.ptr<!rec_C> -> !cir.ptr<!cir.vptr>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.vptr, !cir.ptr<!cir.vptr>
// CIR: }

// Class D constructor
Expand All @@ -118,17 +123,17 @@ int f() {
// CIR: cir.call @_ZN1CC2Ev(%[[C_PTR]], %[[VTT_D_TO_C]]) : (!cir.ptr<!rec_C>, !cir.ptr<!cir.ptr<!void>>) -> ()

// CIR: %{{[0-9]+}} = cir.vtable.address_point(@_ZTV1D, address_point = <index = 0, offset = 3>) : !cir.vptr
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!rec_D>), !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.vtable.get_vptr %{{[0-9]+}} : !cir.ptr<!rec_D> -> !cir.ptr<!cir.vptr>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.vptr, !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.vtable.address_point(@_ZTV1D, address_point = <index = 2, offset = 3>) : !cir.vptr

// CIR: %{{[0-9]+}} = cir.base_class_addr %{{[0-9]+}} : !cir.ptr<!rec_D> nonnull [40] -> !cir.ptr<!rec_A>
// CIR: %{{[0-9]+}} = cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!rec_A>), !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.vtable.get_vptr %{{[0-9]+}} : !cir.ptr<!rec_A> -> !cir.ptr<!cir.vptr>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.vptr, !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.vtable.address_point(@_ZTV1D, address_point = <index = 1, offset = 3>) : !cir.vptr

// CIR: cir.base_class_addr %{{[0-9]+}} : !cir.ptr<!rec_D> nonnull [16] -> !cir.ptr<!rec_C>
// CIR: cir.cast(bitcast, %{{[0-9]+}} : !cir.ptr<!rec_C>), !cir.ptr<!cir.vptr>
// CIR: %{{[0-9]+}} = cir.vtable.get_vptr %{{[0-9]+}} : !cir.ptr<!rec_C> -> !cir.ptr<!cir.vptr>
// CIR: cir.store{{.*}} %{{[0-9]+}}, %{{[0-9]+}} : !cir.vptr, !cir.ptr<!cir.vptr>
// CIR: cir.return
// CIR: }
Expand Down
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