71568a9e28
This patch contains all of the clang changes from D72959. - Generalize the relative vtables ABI such that it can be used by other targets. - Add an enum VTableComponentLayout which controls whether components in the vtable should be pointers to other structs or relative offsets to those structs. Other ABIs can change this enum to restructure how components in the vtable are laid out/accessed. - Add methods to ConstantInitBuilder for inserting relative offsets to a specified position in the aggregate being constructed. - Fix failing tests under new PM and ASan and MSan issues. See D72959 for background info. Differential Revision: https://reviews.llvm.org/D77592
30 lines
1.4 KiB
C++
30 lines
1.4 KiB
C++
// Check the layout of the vtable for a child class that inherits a virtual
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// function but does not override it.
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// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables | FileCheck %s
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class A {
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public:
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virtual void foo();
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};
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// The VTable for B should look similar to the vtable for A but the component for foo() should point to A::foo() and the component for bar() should point to B::bar().
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// CHECK: @_ZTV1B.local = private unnamed_addr constant { [4 x i32] } { [4 x i32] [i32 0, i32 trunc (i64 sub (i64 ptrtoint ({ i8*, i8*, i8* }** @_ZTI1B.rtti_proxy to i64), i64 ptrtoint (i32* getelementptr inbounds ({ [4 x i32] }, { [4 x i32] }* @_ZTV1B.local, i32 0, i32 0, i32 2) to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint (void (%class.A*)* @_ZN1A3fooEv.stub to i64), i64 ptrtoint (i32* getelementptr inbounds ({ [4 x i32] }, { [4 x i32] }* @_ZTV1B.local, i32 0, i32 0, i32 2) to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint (void (%class.B*)* @_ZN1B3barEv.stub to i64), i64 ptrtoint (i32* getelementptr inbounds ({ [4 x i32] }, { [4 x i32] }* @_ZTV1B.local, i32 0, i32 0, i32 2) to i64)) to i32)] }, align 4
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// CHECK: @_ZTV1B = unnamed_addr alias { [4 x i32] }, { [4 x i32] }* @_ZTV1B.local
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class B : public A {
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public:
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virtual void bar();
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};
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void A::foo() {}
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void B::bar() {}
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void A_foo(A *a) {
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a->foo();
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}
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void B_foo(B *b) {
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b->foo();
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}
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