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Differential D82802

[clang][RelativeVTablesABI] Update CodeGenCXX/RelativeVTablesABI/dynamic-cast.cpp
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Authored by leonardchan on Jun 29 2020, 1:01 PM.

Details

Reviewers
phosek
Commits
rGde172dd17f03: [clang][RelativeVTablesABI] Update CodeGenCXX/RelativeVTablesABI/dynamic-cast.
Summary

After c7bcd431d9c4bfeb631a3599f1d628603e6351d6, this test started failing when running with the new pass manager. One of the CHECKs in this file checks how the vtable is loaded for a void cast, which involves taking 2 bitcasts from the pointer to the original object. The order of these bitcasts changes under the new PM. The order doesn't matter, so this relaxes the CHECKs.

Diff Detail

Unit TestsFailed

TimeTest
6,840 mslinux > libomp.env::Unknown Unit Message ("")
1,340 mslinux > libomp.worksharing/for::Unknown Unit Message ("")

Event Timeline

leonardchan created this revision.Jun 29 2020, 1:01 PM
phosek accepted this revision.Jun 29 2020, 1:04 PM

LGTM

This revision is now accepted and ready to land.Jun 29 2020, 1:04 PM
Harbormaster failed remote builds in B62205: Diff 274211!Jun 29 2020, 1:36 PM
Closed by commit rGde172dd17f03: [clang][RelativeVTablesABI] Update CodeGenCXX/RelativeVTablesABI/dynamic-cast. (authored by leonardchan). · Explain WhyJun 29 2020, 1:36 PM
This revision was automatically updated to reflect the committed changes.

Revision Contents

PathSize
clang/
test/
CodeGenCXX/
RelativeVTablesABI/
14 lines

Diff 274211

clang/test/CodeGenCXX/RelativeVTablesABI/dynamic-cast.cpp

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// CHECK-NEXT: ret %class.B* %b // CHECK-NEXT: ret %class.B* %b
// CHECK-NEXT: } // CHECK-NEXT: }
// CHECK: define i8* @_Z9void_castP1B(%class.B* readonly %b) local_unnamed_addr // CHECK: define i8* @_Z9void_castP1B(%class.B* readonly %b) local_unnamed_addr
// CHECK-NEXT: entry: // CHECK-NEXT: entry:
// CHECK-NEXT: [[isnull:%[0-9]+]] = icmp eq %class.B* %b, null // CHECK-NEXT: [[isnull:%[0-9]+]] = icmp eq %class.B* %b, null
// CHECK-NEXT: br i1 [[isnull]], label %[[dynamic_cast_end:[a-z0-9._]+]], label %[[dynamic_cast_notnull:[a-z0-9._]+]] // CHECK-NEXT: br i1 [[isnull]], label %[[dynamic_cast_end:[a-z0-9._]+]], label %[[dynamic_cast_notnull:[a-z0-9._]+]]
// CHECK: [[dynamic_cast_notnull]]: // CHECK: [[dynamic_cast_notnull]]:
// CHECK-NEXT: [[b2:%[0-9]+]] = bitcast %class.B* %b to i32** // CHECK-DAG: [[b2:%[0-9]+]] = bitcast %class.B* %b to i32**
// CHECK-NEXT: [[vtable:%[a-z0-9]+]] = load i32*, i32** [[b2]], align 8 // CHECK-DAG: [[vtable:%[a-z0-9]+]] = load i32*, i32** [[b2]], align 8
// CHECK-NEXT: [[offset_ptr:%.+]] = getelementptr inbounds i32, i32* [[vtable]], i64 -2 // CHECK-DAG: [[offset_ptr:%.+]] = getelementptr inbounds i32, i32* [[vtable]], i64 -2
// CHECK-NEXT: [[offset_to_top:%.+]] = load i32, i32* [[offset_ptr]], align 4 // CHECK-DAG: [[offset_to_top:%.+]] = load i32, i32* [[offset_ptr]], align 4
// CHECK-NEXT: [[b:%[0-9]+]] = bitcast %class.B* %b to i8* // CHECK-DAG: [[b:%[0-9]+]] = bitcast %class.B* %b to i8*
// CHECK-NEXT: [[offset_to_top2:%.+]] = sext i32 [[offset_to_top]] to i64 // CHECK-DAG: [[offset_to_top2:%.+]] = sext i32 [[offset_to_top]] to i64
// CHECK-NEXT: [[casted:%.+]] = getelementptr inbounds i8, i8* [[b]], i64 [[offset_to_top2]] // CHECK-DAG: [[casted:%.+]] = getelementptr inbounds i8, i8* [[b]], i64 [[offset_to_top2]]
// CHECK-NEXT: br label %[[dynamic_cast_end]] // CHECK-NEXT: br label %[[dynamic_cast_end]]
// CHECK: [[dynamic_cast_end]]: // CHECK: [[dynamic_cast_end]]:
// CHECK-NEXT: [[res:%[0-9]+]] = phi i8* [ [[casted]], %[[dynamic_cast_notnull]] ], [ null, %entry ] // CHECK-NEXT: [[res:%[0-9]+]] = phi i8* [ [[casted]], %[[dynamic_cast_notnull]] ], [ null, %entry ]
// CHECK-NEXT: ret i8* [[res]] // CHECK-NEXT: ret i8* [[res]]
// CHECK-NEXT: } // CHECK-NEXT: }
class A { class A {
public: public:
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