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/// Check that the offset to top calculation is adjusted to account for the
/// omitted RTTI entry.
// RUN: %clang_cc1 %s -triple=aarch64-unknown-linux-gnu -fexperimental-omit-vtable-rtti -fno-rtti -o - -emit-llvm | FileCheck -check-prefixes=POINTER %s
// RUN: %clang_cc1 %s -triple=aarch64-unknown-linux-gnu -fexperimental-relative-c++-abi-vtables -fexperimental-omit-vtable-rtti -fno-rtti -o - -emit-llvm | FileCheck -check-prefixes=RELATIVE %s
/// Some important things to check:
/// - The n16 here represents the virtual thunk size. Normally this would be 24
/// to represent 3 components (offset to top, RTTI component, vcall offset),
/// but since one 8-byte component is removed, this is now 16.
// POINTER-LABEL: @_ZTv0_n16_N7Derived1fEi(
// POINTER-NEXT: entry:
// POINTER: [[vtable:%.+]] = load ptr, ptr %this1, align 8
/// Same here - When getting the vbase offset, we subtract 2 pointer sizes
/// instead of 3.
// POINTER-NEXT: [[vbase_offset_ptr:%.+]] = getelementptr inbounds i8, ptr [[vtable]], i64 -16
// POINTER-NEXT: [[vbase_offset:%.+]] = load i64, ptr [[vbase_offset_ptr]], align 8
// POINTER-NEXT: [[adj_this:%.+]] = getelementptr inbounds i8, ptr %this1, i64 [[vbase_offset]]
// POINTER: [[call:%.+]] = tail call noundef i32 @_ZN7Derived1fEi(ptr noundef{{[^,]*}} [[adj_this]], i32 noundef {{.*}})
// POINTER: ret i32 [[call]]
/// For relative vtables, it's almost the same except the offset sizes are
/// halved.
// RELATIVE-LABEL: @_ZTv0_n8_N7Derived1fEi(
// RELATIVE-NEXT: entry:
// RELATIVE: [[vtable:%.+]] = load ptr, ptr %this1, align 8
// RELATIVE-NEXT: [[vbase_offset_ptr:%.+]] = getelementptr inbounds i8, ptr [[vtable]], i64 -8
// RELATIVE-NEXT: [[vbase_offset:%.+]] = load i32, ptr [[vbase_offset_ptr]], align 4
// RELATIVE-NEXT: [[adj_this:%.+]] = getelementptr inbounds i8, ptr %this1, i32 [[vbase_offset]]
// RELATIVE: [[call:%.+]] = tail call noundef i32 @_ZN7Derived1fEi(ptr noundef{{[^,]*}} [[adj_this]], i32 noundef {{.*}})
// RELATIVE: ret i32 [[call]]
class Base {
public:
virtual int f(int x);
private:
long x;
};
class Derived : public virtual Base {
public:
virtual int f(int x);
private:
long y;
};
int Base::f(int x) { return x + 1; }
int Derived::f(int x) { return x + 2; }
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