ARM/AArch64: Attach the FrameSetup MIFlag to CFI instructions.

Debug info marks the first instruction without the FrameSetup flag
as being the end of the function prologue. Any CFI instructions in the
middle of the function prologue would cause debug info to end the prologue
too early and worse, attach the line number of the CFI instruction, which
incidentally is often 0.

llvm-svn: 224294
This commit is contained in:
Adrian Prantl 2014-12-16 00:20:49 +00:00
parent d9a00a9c38
commit b9fa945d51
5 changed files with 256 additions and 13 deletions

View File

@ -1117,8 +1117,12 @@ static DebugLoc findPrologueEndLoc(const MachineFunction *MF) {
for (const auto &MBB : *MF)
for (const auto &MI : MBB)
if (!MI.isDebugValue() && !MI.getFlag(MachineInstr::FrameSetup) &&
!MI.getDebugLoc().isUnknown())
!MI.getDebugLoc().isUnknown()) {
// Did the target forget to set the FrameSetup flag for CFI insns?
assert(!MI.isCFIInstruction() &&
"First non-frame-setup instruction is a CFI instruction.");
return MI.getDebugLoc();
}
return DebugLoc();
}

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@ -196,7 +196,8 @@ void AArch64FrameLowering::emitCalleeSavedFrameMoves(
unsigned CFIIndex = MMI.addFrameInst(MCCFIInstruction::createOffset(
nullptr, DwarfReg, Offset - TotalSkipped));
BuildMI(MBB, MBBI, DL, TII->get(TargetOpcode::CFI_INSTRUCTION))
.addCFIIndex(CFIIndex);
.addCFIIndex(CFIIndex)
.setMIFlags(MachineInstr::FrameSetup);
}
}
@ -234,7 +235,8 @@ void AArch64FrameLowering::emitPrologue(MachineFunction &MF) const {
unsigned CFIIndex = MMI.addFrameInst(
MCCFIInstruction::createDefCfaOffset(FrameLabel, -NumBytes));
BuildMI(MBB, MBBI, DL, TII->get(TargetOpcode::CFI_INSTRUCTION))
.addCFIIndex(CFIIndex);
.addCFIIndex(CFIIndex)
.setMIFlags(MachineInstr::FrameSetup);
} else if (NumBytes) {
++NumRedZoneFunctions;
}
@ -377,26 +379,30 @@ void AArch64FrameLowering::emitPrologue(MachineFunction &MF) const {
unsigned CFIIndex = MMI.addFrameInst(
MCCFIInstruction::createDefCfa(nullptr, Reg, 2 * StackGrowth));
BuildMI(MBB, MBBI, DL, TII->get(TargetOpcode::CFI_INSTRUCTION))
.addCFIIndex(CFIIndex);
.addCFIIndex(CFIIndex)
.setMIFlags(MachineInstr::FrameSetup);
// Record the location of the stored LR
unsigned LR = RegInfo->getDwarfRegNum(AArch64::LR, true);
CFIIndex = MMI.addFrameInst(
MCCFIInstruction::createOffset(nullptr, LR, StackGrowth));
BuildMI(MBB, MBBI, DL, TII->get(TargetOpcode::CFI_INSTRUCTION))
.addCFIIndex(CFIIndex);
.addCFIIndex(CFIIndex)
.setMIFlags(MachineInstr::FrameSetup);
// Record the location of the stored FP
CFIIndex = MMI.addFrameInst(
MCCFIInstruction::createOffset(nullptr, Reg, 2 * StackGrowth));
BuildMI(MBB, MBBI, DL, TII->get(TargetOpcode::CFI_INSTRUCTION))
.addCFIIndex(CFIIndex);
.addCFIIndex(CFIIndex)
.setMIFlags(MachineInstr::FrameSetup);
} else {
// Encode the stack size of the leaf function.
unsigned CFIIndex = MMI.addFrameInst(
MCCFIInstruction::createDefCfaOffset(nullptr, -MFI->getStackSize()));
BuildMI(MBB, MBBI, DL, TII->get(TargetOpcode::CFI_INSTRUCTION))
.addCFIIndex(CFIIndex);
.addCFIIndex(CFIIndex)
.setMIFlags(MachineInstr::FrameSetup);
}
// Now emit the moves for whatever callee saved regs we have.

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@ -203,7 +203,9 @@ struct StackAdjustingInsts {
unsigned CFIIndex = MMI.addFrameInst(
MCCFIInstruction::createDefCfaOffset(nullptr, CFAOffset));
BuildMI(MBB, std::next(Info.I), dl,
TII.get(TargetOpcode::CFI_INSTRUCTION)).addCFIIndex(CFIIndex);
TII.get(TargetOpcode::CFI_INSTRUCTION))
.addCFIIndex(CFIIndex)
.setMIFlags(MachineInstr::FrameSetup);
}
}
};
@ -451,13 +453,15 @@ void ARMFrameLowering::emitPrologue(MachineFunction &MF) const {
nullptr, MRI->getDwarfRegNum(FramePtr, true),
-(ArgRegsSaveSize - FramePtrOffsetInPush)));
BuildMI(MBB, AfterPush, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
.addCFIIndex(CFIIndex);
.addCFIIndex(CFIIndex)
.setMIFlags(MachineInstr::FrameSetup);
} else {
unsigned CFIIndex =
MMI.addFrameInst(MCCFIInstruction::createDefCfaRegister(
nullptr, MRI->getDwarfRegNum(FramePtr, true)));
BuildMI(MBB, AfterPush, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
.addCFIIndex(CFIIndex);
.addCFIIndex(CFIIndex)
.setMIFlags(MachineInstr::FrameSetup);
}
}
@ -491,7 +495,8 @@ void ARMFrameLowering::emitPrologue(MachineFunction &MF) const {
CFIIndex = MMI.addFrameInst(MCCFIInstruction::createOffset(
nullptr, MRI->getDwarfRegNum(Reg, true), MFI->getObjectOffset(FI)));
BuildMI(MBB, Pos, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
.addCFIIndex(CFIIndex);
.addCFIIndex(CFIIndex)
.setMIFlags(MachineInstr::FrameSetup);
break;
}
}
@ -514,7 +519,8 @@ void ARMFrameLowering::emitPrologue(MachineFunction &MF) const {
unsigned CFIIndex = MMI.addFrameInst(
MCCFIInstruction::createOffset(nullptr, DwarfReg, Offset));
BuildMI(MBB, Pos, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
.addCFIIndex(CFIIndex);
.addCFIIndex(CFIIndex)
.setMIFlags(MachineInstr::FrameSetup);
}
break;
}
@ -535,7 +541,8 @@ void ARMFrameLowering::emitPrologue(MachineFunction &MF) const {
unsigned CFIIndex = MMI.addFrameInst(
MCCFIInstruction::createOffset(nullptr, DwarfReg, Offset));
BuildMI(MBB, Pos, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
.addCFIIndex(CFIIndex);
.addCFIIndex(CFIIndex)
.setMIFlags(MachineInstr::FrameSetup);
}
}
}

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@ -0,0 +1,112 @@
; struct A {
; A();
; virtual ~A();
; };
; struct B : A {
; B();
; virtual ~B();
; };
; B::B() {}
; CHECK: __ZN1BC1Ev:
; CHECK: .loc 1 [[@LINE-2]] 0 prologue_end
; CHECK-NOT: .loc 1 0 0 prologue_end
; The location of the prologue_end marker should not be affected by the presence
; of CFI instructions.
; RUN: llc -O0 -filetype=asm < %s | FileCheck %s
; ModuleID = 'test1.cpp'
target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128"
target triple = "aarch64-apple-ios"
%struct.B = type { %struct.A }
%struct.A = type { i32 (...)** }
@_ZTV1B = external unnamed_addr constant [4 x i8*]
; Function Attrs: nounwind
define %struct.B* @_ZN1BC2Ev(%struct.B* %this) unnamed_addr #0 align 2 {
entry:
tail call void @llvm.dbg.value(metadata %struct.B* %this, i64 0, metadata !30, metadata !38), !dbg !39
%0 = getelementptr inbounds %struct.B* %this, i64 0, i32 0, !dbg !40
%call = tail call %struct.A* @_ZN1AC2Ev(%struct.A* %0) #3, !dbg !40
%1 = getelementptr inbounds %struct.B* %this, i64 0, i32 0, i32 0, !dbg !40
store i32 (...)** bitcast (i8** getelementptr inbounds ([4 x i8*]* @_ZTV1B, i64 0, i64 2) to i32 (...)**), i32 (...)*** %1, align 8, !dbg !40, !tbaa !41
ret %struct.B* %this, !dbg !40
}
declare %struct.A* @_ZN1AC2Ev(%struct.A*)
; Function Attrs: nounwind
define %struct.B* @_ZN1BC1Ev(%struct.B* %this) unnamed_addr #0 align 2 {
entry:
tail call void @llvm.dbg.value(metadata %struct.B* %this, i64 0, metadata !34, metadata !38), !dbg !44
tail call void @llvm.dbg.value(metadata %struct.B* %this, i64 0, metadata !45, metadata !38) #3, !dbg !47
%0 = getelementptr inbounds %struct.B* %this, i64 0, i32 0, !dbg !48
%call.i = tail call %struct.A* @_ZN1AC2Ev(%struct.A* %0) #3, !dbg !48
%1 = getelementptr inbounds %struct.B* %this, i64 0, i32 0, i32 0, !dbg !48
store i32 (...)** bitcast (i8** getelementptr inbounds ([4 x i8*]* @_ZTV1B, i64 0, i64 2) to i32 (...)**), i32 (...)*** %1, align 8, !dbg !48, !tbaa !41
ret %struct.B* %this, !dbg !46
}
; Function Attrs: nounwind readnone
declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #2
attributes #0 = { nounwind }
attributes #2 = { nounwind readnone }
attributes #3 = { nounwind }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!35, !36}
!llvm.ident = !{!37}
!0 = !{!"0x11\004\00clang version 3.6.0 (trunk 224279) (llvm/trunk 224283)\001\00\000\00\001", !1, !2, !3, !27, !2, !2} ; [ DW_TAG_compile_unit ] [<stdin>] [DW_LANG_C_plus_plus]
!1 = !{!"<stdin>", !""}
!2 = !{}
!3 = !{!4, !13}
!4 = !{!"0x13\00B\005\0064\0064\000\000\000", !5, null, null, !6, !"_ZTS1A", null, !"_ZTS1B"} ; [ DW_TAG_structure_type ] [B] [line 5, size 64, align 64, offset 0] [def] [from ]
!5 = !{!"test1.cpp", !""}
!6 = !{!7, !8, !12}
!7 = !{!"0x1c\00\000\000\000\000\000", null, !"_ZTS1B", !"_ZTS1A"} ; [ DW_TAG_inheritance ] [line 0, size 0, align 0, offset 0] [from _ZTS1A]
!8 = !{!"0x2e\00B\00B\00\006\000\000\000\000\00256\001\006", !5, !"_ZTS1B", !9, null, null, null, null, null} ; [ DW_TAG_subprogram ] [line 6] [B]
!9 = !{!"0x15\00\000\000\000\000\000\000", null, null, null, !10, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!10 = !{null, !11}
!11 = !{!"0xf\00\000\0064\0064\000\001088\00", null, null, !"_ZTS1B"} ; [ DW_TAG_pointer_type ] [line 0, size 64, align 64, offset 0] [artificial] [from _ZTS1B]
!12 = !{!"0x2e\00~B\00~B\00\007\000\000\001\000\00256\001\007", !5, !"_ZTS1B", !9, !"_ZTS1B", null, null, null, null} ; [ DW_TAG_subprogram ] [line 7] [~B]
!13 = !{!"0x13\00A\001\0064\0064\000\000\000", !5, null, null, !14, !"_ZTS1A", null, !"_ZTS1A"} ; [ DW_TAG_structure_type ] [A] [line 1, size 64, align 64, offset 0] [def] [from ]
!14 = !{!15, !22, !26}
!15 = !{!"0xd\00_vptr$A\000\0064\000\000\0064", !5, !16, !17} ; [ DW_TAG_member ] [_vptr$A] [line 0, size 64, align 0, offset 0] [artificial] [from ]
!16 = !{!"0x29", !5} ; [ DW_TAG_file_type ] [test1.cpp]
!17 = !{!"0xf\00\000\0064\000\000\000", null, null, !18} ; [ DW_TAG_pointer_type ] [line 0, size 64, align 0, offset 0] [from __vtbl_ptr_type]
!18 = !{!"0xf\00__vtbl_ptr_type\000\0064\000\000\000", null, null, !19} ; [ DW_TAG_pointer_type ] [__vtbl_ptr_type] [line 0, size 64, align 0, offset 0] [from ]
!19 = !{!"0x15\00\000\000\000\000\000\000", null, null, null, !20, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!20 = !{!21}
!21 = !{!"0x24\00int\000\0032\0032\000\000\005", null, null} ; [ DW_TAG_base_type ] [int] [line 0, size 32, align 32, offset 0, enc DW_ATE_signed]
!22 = !{!"0x2e\00A\00A\00\002\000\000\000\000\00256\001\002", !5, !"_ZTS1A", !23, null, null, null, null, null} ; [ DW_TAG_subprogram ] [line 2] [A]
!23 = !{!"0x15\00\000\000\000\000\000\000", null, null, null, !24, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!24 = !{null, !25}
!25 = !{!"0xf\00\000\0064\0064\000\001088\00", null, null, !"_ZTS1A"} ; [ DW_TAG_pointer_type ] [line 0, size 64, align 64, offset 0] [artificial] [from _ZTS1A]
!26 = !{!"0x2e\00~A\00~A\00\003\000\000\001\000\00256\001\003", !5, !"_ZTS1A", !23, !"_ZTS1A", null, null, null, null} ; [ DW_TAG_subprogram ] [line 3] [~A]
!27 = !{!28, !32}
!28 = !{!"0x2e\00B\00B\00_ZN1BC2Ev\009\000\001\000\000\00256\001\009", !5, !"_ZTS1B", !9, null, %struct.B* (%struct.B*)* @_ZN1BC2Ev, null, !8, !29} ; [ DW_TAG_subprogram ] [line 9] [def] [B]
!29 = !{!30}
!30 = !{!"0x101\00this\0016777216\001088", !28, null, !31} ; [ DW_TAG_arg_variable ] [this] [line 0]
!31 = !{!"0xf\00\000\0064\0064\000\000", null, null, !"_ZTS1B"} ; [ DW_TAG_pointer_type ] [line 0, size 64, align 64, offset 0] [from _ZTS1B]
!32 = !{!"0x2e\00B\00B\00_ZN1BC1Ev\009\000\001\000\000\00256\001\009", !5, !"_ZTS1B", !9, null, %struct.B* (%struct.B*)* @_ZN1BC1Ev, null, !8, !33} ; [ DW_TAG_subprogram ] [line 9] [def] [B]
!33 = !{!34}
!34 = !{!"0x101\00this\0016777216\001088", !32, null, !31} ; [ DW_TAG_arg_variable ] [this] [line 0]
!35 = !{i32 2, !"Dwarf Version", i32 4}
!36 = !{i32 2, !"Debug Info Version", i32 2}
!37 = !{!"clang version 3.6.0 (trunk 224279) (llvm/trunk 224283)"}
!38 = !{!"0x102"} ; [ DW_TAG_expression ]
!39 = !{i32 0, i32 0, !28, null}
!40 = !{i32 9, i32 0, !28, null}
!41 = !{!42, !42, i64 0}
!42 = !{!"vtable pointer", !43, i64 0}
!43 = !{!"Simple C/C++ TBAA"}
!44 = !{i32 0, i32 0, !32, null}
!45 = !{!"0x101\00this\0016777216\001088", !28, null, !31, !46} ; [ DW_TAG_arg_variable ] [this] [line 0]
!46 = !{i32 9, i32 0, !32, null}
!47 = !{i32 0, i32 0, !28, !46}
!48 = !{i32 9, i32 0, !28, !46}

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@ -0,0 +1,114 @@
; struct A {
; A();
; virtual ~A();
; };
; struct B : A {
; B();
; virtual ~B();
; };
; B::B() {}
; CHECK: __ZN1BC1Ev:
; CHECK: .loc 1 [[@LINE-2]] 0 prologue_end
; CHECK-NOT: .loc 1 0 0 prologue_end
; The location of the prologue_end marker should not be affected by the presence
; of CFI instructions.
; RUN: llc -O0 -filetype=asm < %s | FileCheck %s
; ModuleID = 'test1.cpp'
target datalayout = "e-m:o-p:32:32-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32"
target triple = "thumbv7-apple-ios"
%struct.B = type { %struct.A }
%struct.A = type { i32 (...)** }
@_ZTV1B = external unnamed_addr constant [4 x i8*]
; Function Attrs: nounwind
define %struct.B* @_ZN1BC2Ev(%struct.B* %this) unnamed_addr #0 align 2 {
entry:
tail call void @llvm.dbg.value(metadata %struct.B* %this, i64 0, metadata !30, metadata !40), !dbg !41
%0 = getelementptr inbounds %struct.B* %this, i32 0, i32 0, !dbg !42
%call = tail call %struct.A* @_ZN1AC2Ev(%struct.A* %0) #3, !dbg !42
%1 = getelementptr inbounds %struct.B* %this, i32 0, i32 0, i32 0, !dbg !42
store i32 (...)** bitcast (i8** getelementptr inbounds ([4 x i8*]* @_ZTV1B, i32 0, i32 2) to i32 (...)**), i32 (...)*** %1, align 4, !dbg !42, !tbaa !43
ret %struct.B* %this, !dbg !42
}
declare %struct.A* @_ZN1AC2Ev(%struct.A*)
; Function Attrs: nounwind
define %struct.B* @_ZN1BC1Ev(%struct.B* %this) unnamed_addr #0 align 2 {
entry:
tail call void @llvm.dbg.value(metadata %struct.B* %this, i64 0, metadata !34, metadata !40), !dbg !46
tail call void @llvm.dbg.value(metadata %struct.B* %this, i64 0, metadata !47, metadata !40) #3, !dbg !49
%0 = getelementptr inbounds %struct.B* %this, i32 0, i32 0, !dbg !50
%call.i = tail call %struct.A* @_ZN1AC2Ev(%struct.A* %0) #3, !dbg !50
%1 = getelementptr inbounds %struct.B* %this, i32 0, i32 0, i32 0, !dbg !50
store i32 (...)** bitcast (i8** getelementptr inbounds ([4 x i8*]* @_ZTV1B, i32 0, i32 2) to i32 (...)**), i32 (...)*** %1, align 4, !dbg !50, !tbaa !43
ret %struct.B* %this, !dbg !48
}
; Function Attrs: nounwind readnone
declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #2
attributes #0 = { nounwind }
attributes #2 = { nounwind readnone }
attributes #3 = { nounwind }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!35, !36, !37, !38}
!llvm.ident = !{!39}
!0 = !{!"0x11\004\00clang version 3.6.0 (trunk 224279) (llvm/trunk 224283)\001\00\000\00\001", !1, !2, !3, !27, !2, !2} ; [ DW_TAG_compile_unit ] [<stdin>] [DW_LANG_C_plus_plus]
!1 = !{!"<stdin>", !""}
!2 = !{}
!3 = !{!4, !13}
!4 = !{!"0x13\00B\005\0032\0032\000\000\000", !5, null, null, !6, !"_ZTS1A", null, !"_ZTS1B"} ; [ DW_TAG_structure_type ] [B] [line 5, size 32, align 32, offset 0] [def] [from ]
!5 = !{!"test1.cpp", !""}
!6 = !{!7, !8, !12}
!7 = !{!"0x1c\00\000\000\000\000\000", null, !"_ZTS1B", !"_ZTS1A"} ; [ DW_TAG_inheritance ] [line 0, size 0, align 0, offset 0] [from _ZTS1A]
!8 = !{!"0x2e\00B\00B\00\006\000\000\000\000\00256\001\006", !5, !"_ZTS1B", !9, null, null, null, null, null} ; [ DW_TAG_subprogram ] [line 6] [B]
!9 = !{!"0x15\00\000\000\000\000\000\000", null, null, null, !10, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!10 = !{null, !11}
!11 = !{!"0xf\00\000\0032\0032\000\001088\00", null, null, !"_ZTS1B"} ; [ DW_TAG_pointer_type ] [line 0, size 32, align 32, offset 0] [artificial] [from _ZTS1B]
!12 = !{!"0x2e\00~B\00~B\00\007\000\000\001\000\00256\001\007", !5, !"_ZTS1B", !9, !"_ZTS1B", null, null, null, null} ; [ DW_TAG_subprogram ] [line 7] [~B]
!13 = !{!"0x13\00A\001\0032\0032\000\000\000", !5, null, null, !14, !"_ZTS1A", null, !"_ZTS1A"} ; [ DW_TAG_structure_type ] [A] [line 1, size 32, align 32, offset 0] [def] [from ]
!14 = !{!15, !22, !26}
!15 = !{!"0xd\00_vptr$A\000\0032\000\000\0064", !5, !16, !17} ; [ DW_TAG_member ] [_vptr$A] [line 0, size 32, align 0, offset 0] [artificial] [from ]
!16 = !{!"0x29", !5} ; [ DW_TAG_file_type ] [test1.cpp]
!17 = !{!"0xf\00\000\0032\000\000\000", null, null, !18} ; [ DW_TAG_pointer_type ] [line 0, size 32, align 0, offset 0] [from __vtbl_ptr_type]
!18 = !{!"0xf\00__vtbl_ptr_type\000\0032\000\000\000", null, null, !19} ; [ DW_TAG_pointer_type ] [__vtbl_ptr_type] [line 0, size 32, align 0, offset 0] [from ]
!19 = !{!"0x15\00\000\000\000\000\000\000", null, null, null, !20, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!20 = !{!21}
!21 = !{!"0x24\00int\000\0032\0032\000\000\005", null, null} ; [ DW_TAG_base_type ] [int] [line 0, size 32, align 32, offset 0, enc DW_ATE_signed]
!22 = !{!"0x2e\00A\00A\00\002\000\000\000\000\00256\001\002", !5, !"_ZTS1A", !23, null, null, null, null, null} ; [ DW_TAG_subprogram ] [line 2] [A]
!23 = !{!"0x15\00\000\000\000\000\000\000", null, null, null, !24, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!24 = !{null, !25}
!25 = !{!"0xf\00\000\0032\0032\000\001088\00", null, null, !"_ZTS1A"} ; [ DW_TAG_pointer_type ] [line 0, size 32, align 32, offset 0] [artificial] [from _ZTS1A]
!26 = !{!"0x2e\00~A\00~A\00\003\000\000\001\000\00256\001\003", !5, !"_ZTS1A", !23, !"_ZTS1A", null, null, null, null} ; [ DW_TAG_subprogram ] [line 3] [~A]
!27 = !{!28, !32}
!28 = !{!"0x2e\00B\00B\00_ZN1BC2Ev\009\000\001\000\000\00256\001\009", !5, !"_ZTS1B", !9, null, %struct.B* (%struct.B*)* @_ZN1BC2Ev, null, !8, !29} ; [ DW_TAG_subprogram ] [line 9] [def] [B]
!29 = !{!30}
!30 = !{!"0x101\00this\0016777216\001088", !28, null, !31} ; [ DW_TAG_arg_variable ] [this] [line 0]
!31 = !{!"0xf\00\000\0032\0032\000\000", null, null, !"_ZTS1B"} ; [ DW_TAG_pointer_type ] [line 0, size 32, align 32, offset 0] [from _ZTS1B]
!32 = !{!"0x2e\00B\00B\00_ZN1BC1Ev\009\000\001\000\000\00256\001\009", !5, !"_ZTS1B", !9, null, %struct.B* (%struct.B*)* @_ZN1BC1Ev, null, !8, !33} ; [ DW_TAG_subprogram ] [line 9] [def] [B]
!33 = !{!34}
!34 = !{!"0x101\00this\0016777216\001088", !32, null, !31} ; [ DW_TAG_arg_variable ] [this] [line 0]
!35 = !{i32 2, !"Dwarf Version", i32 4}
!36 = !{i32 2, !"Debug Info Version", i32 2}
!37 = !{i32 1, !"wchar_size", i32 4}
!38 = !{i32 1, !"min_enum_size", i32 4}
!39 = !{!"clang version 3.6.0 (trunk 224279) (llvm/trunk 224283)"}
!40 = !{!"0x102"} ; [ DW_TAG_expression ]
!41 = !{i32 0, i32 0, !28, null}
!42 = !{i32 9, i32 0, !28, null}
!43 = !{!44, !44, i64 0}
!44 = !{!"vtable pointer", !45, i64 0}
!45 = !{!"Simple C/C++ TBAA"}
!46 = !{i32 0, i32 0, !32, null}
!47 = !{!"0x101\00this\0016777216\001088", !28, null, !31, !48} ; [ DW_TAG_arg_variable ] [this] [line 0]
!48 = !{i32 9, i32 0, !32, null}
!49 = !{i32 0, i32 0, !28, !48}
!50 = !{i32 9, i32 0, !28, !48}