[llvm] r248933 - Fix debug info with SafeStack.
Evgeniy Stepanov via llvm-commits
llvm-commits at lists.llvm.org
Wed Sep 30 12:55:44 PDT 2015
Author: eugenis
Date: Wed Sep 30 14:55:43 2015
New Revision: 248933
URL: http://llvm.org/viewvc/llvm-project?rev=248933&view=rev
Log:
Fix debug info with SafeStack.
Added:
llvm/trunk/test/DebugInfo/Generic/dw_op_minus.ll
llvm/trunk/test/Transforms/SafeStack/debug-loc.ll
Modified:
llvm/trunk/include/llvm/Transforms/Utils/Local.h
llvm/trunk/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
llvm/trunk/lib/IR/DebugInfoMetadata.cpp
llvm/trunk/lib/Transforms/Instrumentation/SafeStack.cpp
llvm/trunk/lib/Transforms/Utils/Local.cpp
Modified: llvm/trunk/include/llvm/Transforms/Utils/Local.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Utils/Local.h?rev=248933&r1=248932&r2=248933&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Transforms/Utils/Local.h (original)
+++ llvm/trunk/include/llvm/Transforms/Utils/Local.h Wed Sep 30 14:55:43 2015
@@ -272,10 +272,11 @@ bool LowerDbgDeclare(Function &F);
DbgDeclareInst *FindAllocaDbgDeclare(Value *V);
/// \brief Replaces llvm.dbg.declare instruction when an alloca is replaced with
-/// a new value. If Deref is true, tan additional DW_OP_deref is prepended to
-/// the expression.
+/// a new value. If Deref is true, an additional DW_OP_deref is prepended to the
+/// expression. If Offset is non-zero, a constant displacement is added to the
+/// expression (after the optional Deref). Offset can be negative.
bool replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
- DIBuilder &Builder, bool Deref);
+ DIBuilder &Builder, bool Deref, int Offset = 0);
/// Replace 'BB's terminator with one that does not have an unwind successor
/// block. Rewrites `invoke` to `call`, `catchendpad unwind label %foo` to
Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfExpression.cpp?rev=248933&r1=248932&r2=248933&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfExpression.cpp (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfExpression.cpp Wed Sep 30 14:55:43 2015
@@ -211,12 +211,15 @@ bool DwarfExpression::AddMachineRegExpre
return AddMachineRegPiece(MachineReg, SizeInBits,
getOffsetOrZero(OffsetInBits, PieceOffsetInBits));
}
- case dwarf::DW_OP_plus: {
- // [DW_OP_reg,Offset,DW_OP_plus,DW_OP_deref] --> [DW_OP_breg,Offset].
+ case dwarf::DW_OP_plus:
+ case dwarf::DW_OP_minus: {
+ // [DW_OP_reg,Offset,DW_OP_plus, DW_OP_deref] --> [DW_OP_breg, Offset].
+ // [DW_OP_reg,Offset,DW_OP_minus,DW_OP_deref] --> [DW_OP_breg,-Offset].
auto N = I.getNext();
if (N != E && N->getOp() == dwarf::DW_OP_deref) {
unsigned Offset = I->getArg(0);
- ValidReg = AddMachineRegIndirect(MachineReg, Offset);
+ ValidReg = AddMachineRegIndirect(
+ MachineReg, I->getOp() == dwarf::DW_OP_plus ? Offset : -Offset);
std::advance(I, 2);
break;
} else
@@ -255,6 +258,12 @@ void DwarfExpression::AddExpression(DIEx
EmitOp(dwarf::DW_OP_plus_uconst);
EmitUnsigned(I->getArg(0));
break;
+ case dwarf::DW_OP_minus:
+ // There is no OP_minus_uconst.
+ EmitOp(dwarf::DW_OP_constu);
+ EmitUnsigned(I->getArg(0));
+ EmitOp(dwarf::DW_OP_minus);
+ break;
case dwarf::DW_OP_deref:
EmitOp(dwarf::DW_OP_deref);
break;
Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp?rev=248933&r1=248932&r2=248933&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp Wed Sep 30 14:55:43 2015
@@ -4394,15 +4394,9 @@ SelectionDAGBuilder::visitIntrinsicCall(
N);
return nullptr;
}
- } else if (AI)
+ } else {
SDV = DAG.getDbgValue(Variable, Expression, N.getNode(), N.getResNo(),
true, 0, dl, SDNodeOrder);
- else {
- // Can't do anything with other non-AI cases yet.
- DEBUG(dbgs() << "Dropping debug info for " << DI << "\n");
- DEBUG(dbgs() << "non-AllocaInst issue for Address: \n\t");
- DEBUG(Address->dump());
- return nullptr;
}
DAG.AddDbgValue(SDV, N.getNode(), isParameter);
} else {
Modified: llvm/trunk/lib/IR/DebugInfoMetadata.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/IR/DebugInfoMetadata.cpp?rev=248933&r1=248932&r2=248933&view=diff
==============================================================================
--- llvm/trunk/lib/IR/DebugInfoMetadata.cpp (original)
+++ llvm/trunk/lib/IR/DebugInfoMetadata.cpp Wed Sep 30 14:55:43 2015
@@ -496,6 +496,7 @@ unsigned DIExpression::ExprOperand::getS
case dwarf::DW_OP_bit_piece:
return 3;
case dwarf::DW_OP_plus:
+ case dwarf::DW_OP_minus:
return 2;
default:
return 1;
@@ -516,6 +517,7 @@ bool DIExpression::isValid() const {
// Piece expressions must be at the end.
return I->get() + I->getSize() == E->get();
case dwarf::DW_OP_plus:
+ case dwarf::DW_OP_minus:
case dwarf::DW_OP_deref:
break;
}
Modified: llvm/trunk/lib/Transforms/Instrumentation/SafeStack.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/SafeStack.cpp?rev=248933&r1=248932&r2=248933&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Instrumentation/SafeStack.cpp (original)
+++ llvm/trunk/lib/Transforms/Instrumentation/SafeStack.cpp Wed Sep 30 14:55:43 2015
@@ -443,7 +443,7 @@ SafeStack::moveStaticAllocasToUnsafeStac
cast<Instruction>(NewAI)->takeName(AI);
// Replace alloc with the new location.
- replaceDbgDeclareForAlloca(AI, NewAI, DIB, /*Deref=*/true);
+ replaceDbgDeclareForAlloca(AI, BasePointer, DIB, /*Deref=*/true, -StaticOffset);
AI->replaceAllUsesWith(NewAI);
AI->eraseFromParent();
}
Modified: llvm/trunk/lib/Transforms/Utils/Local.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/Local.cpp?rev=248933&r1=248932&r2=248933&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/Local.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/Local.cpp Wed Sep 30 14:55:43 2015
@@ -1136,7 +1136,7 @@ DbgDeclareInst *llvm::FindAllocaDbgDecla
}
bool llvm::replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
- DIBuilder &Builder, bool Deref) {
+ DIBuilder &Builder, bool Deref, int Offset) {
DbgDeclareInst *DDI = FindAllocaDbgDeclare(AI);
if (!DDI)
return false;
@@ -1145,13 +1145,21 @@ bool llvm::replaceDbgDeclareForAlloca(Al
auto *DIExpr = DDI->getExpression();
assert(DIVar && "Missing variable");
- if (Deref) {
+ if (Deref || Offset) {
// Create a copy of the original DIDescriptor for user variable, prepending
// "deref" operation to a list of address elements, as new llvm.dbg.declare
// will take a value storing address of the memory for variable, not
// alloca itself.
SmallVector<uint64_t, 4> NewDIExpr;
- NewDIExpr.push_back(dwarf::DW_OP_deref);
+ if (Deref)
+ NewDIExpr.push_back(dwarf::DW_OP_deref);
+ if (Offset > 0) {
+ NewDIExpr.push_back(dwarf::DW_OP_plus);
+ NewDIExpr.push_back(Offset);
+ } else if (Offset < 0) {
+ NewDIExpr.push_back(dwarf::DW_OP_minus);
+ NewDIExpr.push_back(-Offset);
+ }
if (DIExpr)
NewDIExpr.append(DIExpr->elements_begin(), DIExpr->elements_end());
DIExpr = Builder.createExpression(NewDIExpr);
Added: llvm/trunk/test/DebugInfo/Generic/dw_op_minus.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/Generic/dw_op_minus.ll?rev=248933&view=auto
==============================================================================
--- llvm/trunk/test/DebugInfo/Generic/dw_op_minus.ll (added)
+++ llvm/trunk/test/DebugInfo/Generic/dw_op_minus.ll Wed Sep 30 14:55:43 2015
@@ -0,0 +1,84 @@
+; Test dwarf codegen of DW_OP_minus.
+; RUN: llc -O0 -mtriple=x86_64-unknown-linux-gnu < %s | FileCheck %s
+
+; This was built by compiling the following source with SafeStack and
+; simplifying the result a little.
+; extern "C" {
+; void Capture(int *);
+; void f() {
+; int buf[100];
+; Capture(buf);
+; }
+; }
+; The interesting part is !DIExpression(DW_OP_deref, DW_OP_minus, 400)
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+ at __safestack_unsafe_stack_ptr = external thread_local(initialexec) global i8*
+
+define void @f() {
+entry:
+ %unsafe_stack_ptr = load i8*, i8** @__safestack_unsafe_stack_ptr
+ %unsafe_stack_static_top = getelementptr i8, i8* %unsafe_stack_ptr, i32 -400
+ store i8* %unsafe_stack_static_top, i8** @__safestack_unsafe_stack_ptr
+ %0 = getelementptr i8, i8* %unsafe_stack_ptr, i32 -400
+ %buf = bitcast i8* %0 to [100 x i32]*
+ %1 = bitcast [100 x i32]* %buf to i8*, !dbg !16
+ call void @llvm.dbg.declare(metadata i8* %unsafe_stack_ptr, metadata !8, metadata !17), !dbg !18
+ %arraydecay = getelementptr inbounds [100 x i32], [100 x i32]* %buf, i64 0, i64 0, !dbg !19
+ call void @Capture(i32* %arraydecay), !dbg !20
+ store i8* %unsafe_stack_ptr, i8** @__safestack_unsafe_stack_ptr, !dbg !21
+ ret void, !dbg !21
+}
+
+; Function Attrs: nounwind readnone
+declare void @llvm.dbg.declare(metadata, metadata, metadata) nounwind readnone
+
+declare void @Capture(i32*)
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!13, !14}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 3.8.0 (trunk 248518) (llvm/trunk 248512)", isOptimized: true, runtimeVersion: 0, emissionKind: 1, enums: !2, subprograms: !3)
+!1 = !DIFile(filename: "1.cc", directory: "/tmp")
+!2 = !{}
+!3 = !{!4}
+!4 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 4, type: !5, isLocal: false, isDefinition: true, scopeLine: 4, flags: DIFlagPrototyped, isOptimized: true, function: void ()* @f, variables: !7)
+!5 = !DISubroutineType(types: !6)
+!6 = !{null}
+!7 = !{!8}
+!8 = !DILocalVariable(name: "buf", scope: !4, file: !1, line: 5, type: !9)
+!9 = !DICompositeType(tag: DW_TAG_array_type, baseType: !10, size: 3200, align: 32, elements: !11)
+!10 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!11 = !{!12}
+!12 = !DISubrange(count: 100)
+!13 = !{i32 2, !"Dwarf Version", i32 4}
+!14 = !{i32 2, !"Debug Info Version", i32 3}
+!15 = !{!"clang version 3.8.0 (trunk 248518) (llvm/trunk 248512)"}
+!16 = !DILocation(line: 5, column: 3, scope: !4)
+!17 = !DIExpression(DW_OP_deref, DW_OP_minus, 400)
+!18 = !DILocation(line: 5, column: 7, scope: !4)
+!19 = !DILocation(line: 6, column: 11, scope: !4)
+!20 = !DILocation(line: 6, column: 3, scope: !4)
+!21 = !DILocation(line: 7, column: 1, scope: !4)
+
+; RCX - 400
+; CHECK: .short 6 # Loc expr size
+; CHECK-NEXT: .byte 114 # DW_OP_breg2
+; CHECK-NEXT: .byte 0 # 0
+; CHECK-NEXT: .byte 16 # DW_OP_constu
+; CHECK-NEXT: .byte 144 # 400
+; CHECK-NEXT: .byte 3 # DW_OP_minus
+; CHECK-NEXT: .byte 28
+
+; RCX is clobbered in call @Capture, but there is a spilled copy.
+; *(RSP + 8) - 400
+; CHECK: .short 7 # Loc expr size
+; CHECK-NEXT: .byte 119 # DW_OP_breg7
+; CHECK-NEXT: .byte 8 # 8
+; CHECK-NEXT: .byte 6 # DW_OP_deref
+; CHECK-NEXT: .byte 16 # DW_OP_constu
+; CHECK-NEXT: .byte 144 # 400
+; CHECK-NEXT: .byte 3 # DW_OP_minus
+; CHECK-NEXT: .byte 28
Added: llvm/trunk/test/Transforms/SafeStack/debug-loc.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/debug-loc.ll?rev=248933&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/SafeStack/debug-loc.ll (added)
+++ llvm/trunk/test/Transforms/SafeStack/debug-loc.ll Wed Sep 30 14:55:43 2015
@@ -0,0 +1,83 @@
+; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
+
+; Test debug location for the local variables moved onto the unsafe stack.
+; CHECK: define void @f
+; CHECK: %[[USP:.*]] = load i8*, i8** @__safestack_unsafe_stack_ptr
+
+; dbg.declare for %buf is gone; replaced with dbg.declare based off the unsafe stack pointer
+; CHECK-NOT: @llvm.dbg.declare.*%buf
+; CHECK: call void @llvm.dbg.declare(metadata i8* %[[USP]], metadata ![[VAR:.*]], metadata ![[EXPR:.*]])
+
+; dbg.declare appears before the first use of %buf
+; CHECK: getelementptr{{.*}}%buf
+; CHECK: call{{.*}}@Capture
+; CHECK: ret void
+
+; dbg.declare describes "buf"...
+; CHECK: ![[VAR]] = !DILocalVariable(name: "buf"
+
+; ... as an offset from the unsafe stack pointer
+; CHECK: ![[EXPR]] = !DIExpression(DW_OP_deref, DW_OP_minus, 400)
+
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+; Function Attrs: safestack uwtable
+define void @f() #0 {
+entry:
+ %buf = alloca [100 x i32], align 16
+ %0 = bitcast [100 x i32]* %buf to i8*, !dbg !16
+ call void @llvm.lifetime.start(i64 400, i8* %0) #4, !dbg !16
+ tail call void @llvm.dbg.declare(metadata [100 x i32]* %buf, metadata !8, metadata !17), !dbg !18
+
+
+ %arraydecay = getelementptr inbounds [100 x i32], [100 x i32]* %buf, i64 0, i64 0, !dbg !19
+ call void @Capture(i32* %arraydecay), !dbg !20
+ call void @llvm.lifetime.end(i64 400, i8* %0) #4, !dbg !21
+ ret void, !dbg !21
+}
+
+; Function Attrs: nounwind argmemonly
+declare void @llvm.lifetime.start(i64, i8* nocapture) #1
+
+; Function Attrs: nounwind readnone
+declare void @llvm.dbg.declare(metadata, metadata, metadata) #2
+
+declare void @Capture(i32*) #3
+
+; Function Attrs: nounwind argmemonly
+declare void @llvm.lifetime.end(i64, i8* nocapture) #1
+
+attributes #0 = { safestack uwtable "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { nounwind argmemonly }
+attributes #2 = { nounwind readnone }
+attributes #3 = { "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #4 = { nounwind }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!13, !14}
+!llvm.ident = !{!15}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 3.8.0 (trunk 248518) (llvm/trunk 248512)", isOptimized: true, runtimeVersion: 0, emissionKind: 1, enums: !2, subprograms: !3)
+!1 = !DIFile(filename: "1.cc", directory: "/tmp")
+!2 = !{}
+!3 = !{!4}
+!4 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 4, type: !5, isLocal: false, isDefinition: true, scopeLine: 4, flags: DIFlagPrototyped, isOptimized: true, function: void ()* @f, variables: !7)
+!5 = !DISubroutineType(types: !6)
+!6 = !{null}
+!7 = !{!8}
+!8 = !DILocalVariable(name: "buf", scope: !4, file: !1, line: 5, type: !9)
+!9 = !DICompositeType(tag: DW_TAG_array_type, baseType: !10, size: 3200, align: 32, elements: !11)
+!10 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!11 = !{!12}
+!12 = !DISubrange(count: 100)
+!13 = !{i32 2, !"Dwarf Version", i32 4}
+!14 = !{i32 2, !"Debug Info Version", i32 3}
+!15 = !{!"clang version 3.8.0 (trunk 248518) (llvm/trunk 248512)"}
+!16 = !DILocation(line: 5, column: 3, scope: !4)
+!17 = !DIExpression()
+!18 = !DILocation(line: 5, column: 7, scope: !4)
+!19 = !DILocation(line: 6, column: 11, scope: !4)
+!20 = !DILocation(line: 6, column: 3, scope: !4)
+!21 = !DILocation(line: 7, column: 1, scope: !4)
More information about the llvm-commits
mailing list