[DebugInfo] LowerDbgDeclare: Add derefs when handling CallInst users
LowerDbgDeclare inserts a dbg.value before each use of an address
described by a dbg.declare. When inserting a dbg.value before a CallInst
use, however, it fails to append DW_OP_deref to the DIExpression.
The DW_OP_deref is needed to reflect the fact that a dbg.value describes
a source variable directly (as opposed to a dbg.declare, which relies on
pointer indirection).
This patch adds in the DW_OP_deref where needed. This results in the
correct values being shown during a debug session for a program compiled
with ASan and optimizations (see https://reviews.llvm.org/D49520). Note
that ConvertDebugDeclareToDebugValue is already correct -- no changes
there were needed.
One complication is that SelectionDAG is unable to distinguish between
direct and indirect frame-index (FRAMEIX) SDDbgValues. This patch also
fixes this long-standing issue in order to not regress integration tests
relying on the incorrect assumption that all frame-index SDDbgValues are
indirect. This is a necessary fix: the newly-added DW_OP_derefs cannot
be lowered properly otherwise. Basically the fix prevents a direct
SDDbgValue with DIExpression(DW_OP_deref) from being dereferenced twice
by a debugger. There were a handful of tests relying on this incorrect
"FRAMEIX => indirect" assumption which actually had incorrect
DW_AT_locations: these are all fixed up in this patch.
Testing:
- check-llvm, and an end-to-end test using lldb to debug an optimized
program.
- Existing unit tests for DIExpression::appendToStack fully cover the
new DIExpression::append utility.
- check-debuginfo (the debug info integration tests)
Differential Revision: https://reviews.llvm.org/D49454
llvm-svn: 338069
diff --git a/llvm/test/DebugInfo/AArch64/coalescing.ll b/llvm/test/DebugInfo/AArch64/coalescing.ll
index 0f65856..c39f884 100644
--- a/llvm/test/DebugInfo/AArch64/coalescing.ll
+++ b/llvm/test/DebugInfo/AArch64/coalescing.ll
@@ -20,10 +20,13 @@
%0 = bitcast i32* %size to i8*, !dbg !15
%call = call i8* @_Z3fooPv(i8* %0) #3, !dbg !15
call void @llvm.dbg.value(metadata i32* %size, metadata !10, metadata !16), !dbg !17
+
+ ; The *location* of the variable should be $sp+12. This tells the debugger to
+ ; look up its value in [$sp+12].
; CHECK: .debug_info contents:
; CHECK: DW_TAG_variable
; CHECK-NEXT: DW_AT_location
- ; CHECK-NEXT: DW_OP_breg31 WSP+12, DW_OP_deref
+ ; CHECK-NEXT: DW_OP_breg31 WSP+12
; CHECK-NEXT: DW_AT_name {{.*}}"size"
ret void, !dbg !18
}
diff --git a/llvm/test/DebugInfo/Mips/dsr-fixed-objects.ll b/llvm/test/DebugInfo/Mips/dsr-fixed-objects.ll
index 0101868..ebbe64a 100644
--- a/llvm/test/DebugInfo/Mips/dsr-fixed-objects.ll
+++ b/llvm/test/DebugInfo/Mips/dsr-fixed-objects.ll
@@ -20,11 +20,12 @@
declare void @foo(i32*)
+; CHECK: DW_AT_name {{.*}}"f0"
; CHECK: DW_AT_name {{.*}}"e"
; CHECK: DW_TAG_variable
; CHECK-NEXT: DW_AT_location [DW_FORM_sec_offset] (
; CHECK-NEXT: [0x00000028, 0x0000002c): DW_OP_reg1 AT_64
-; CHECK-NEXT: [0x0000002c, 0x00000048): DW_OP_breg29 SP_64+16, DW_OP_deref)
+; CHECK-NEXT: [0x0000002c, 0x00000048): DW_OP_breg29 SP_64+16)
; CHECK-NEXT: DW_AT_name [DW_FORM_strp] ( .debug_str[0x0000006b] = "x")
define i32 @f0(i32 signext %a, i32 signext %b, i32 signext %c, i32 signext %d, i32 signext %e) !dbg !4 {
@@ -55,7 +56,7 @@
; CHECK: DW_TAG_variable
; CHECK-NEXT: DW_AT_location [DW_FORM_sec_offset] (
; CHECK-NEXT: [0x00000080, 0x00000084): DW_OP_reg1 AT_64
-; CHECK-NEXT: [0x00000084, 0x00000098): DW_OP_breg29 SP_64+16, DW_OP_deref)
+; CHECK-NEXT: [0x00000084, 0x00000098): DW_OP_breg29 SP_64+16)
; CHECK-NEXT: DW_AT_name [DW_FORM_strp] ( .debug_str[0x0000006b] = "x")
define i32 @f1(i32 signext %a, i32 signext %b, i32 signext %c, i32 signext %d, i32 signext %e) !dbg !15 {
diff --git a/llvm/test/DebugInfo/X86/bbjoin.ll b/llvm/test/DebugInfo/X86/bbjoin.ll
index 02b6d41..b3f20a9 100644
--- a/llvm/test/DebugInfo/X86/bbjoin.ll
+++ b/llvm/test/DebugInfo/X86/bbjoin.ll
@@ -12,7 +12,7 @@
; CHECK: ![[X:.*]] = !DILocalVariable(name: "x",
; CHECK: bb.0.entry:
; CHECK: DBG_VALUE 23, debug-use $noreg, ![[X]],
-; CHECK: DBG_VALUE debug-use $rsp, 0, ![[X]], !DIExpression(DW_OP_plus_uconst, 4, DW_OP_deref),
+; CHECK: DBG_VALUE debug-use $rsp, debug-use $noreg, ![[X]], !DIExpression(DW_OP_plus_uconst, 4, DW_OP_deref),
; CHECK: bb.1.if.then:
; CHECK: DBG_VALUE 43, debug-use $noreg, ![[X]],
; CHECK: bb.2.if.end:
diff --git a/llvm/test/DebugInfo/X86/dbg-value-const-byref.ll b/llvm/test/DebugInfo/X86/dbg-value-const-byref.ll
index 49d0ea2..945c95f 100644
--- a/llvm/test/DebugInfo/X86/dbg-value-const-byref.ll
+++ b/llvm/test/DebugInfo/X86/dbg-value-const-byref.ll
@@ -25,7 +25,7 @@
; CHECK-NEXT: [0x{{0*.*}}, 0x[[C1:.*]]): DW_OP_consts +3
; CHECK-NEXT: [0x[[C1]], 0x[[C2:.*]]): DW_OP_consts +7
; CHECK-NEXT: [0x[[C2]], 0x[[R1:.*]]): DW_OP_reg0 RAX
-; CHECK-NEXT: [0x[[R1]], 0x[[R2:.*]]): DW_OP_breg7 RSP+4, DW_OP_deref)
+; CHECK-NEXT: [0x[[R1]], 0x[[R2:.*]]): DW_OP_breg7 RSP+4)
; CHECK-NOT: DW_TAG
; CHECK: DW_AT_name{{.*}}"i"
diff --git a/llvm/test/DebugInfo/X86/dbg-value-frame-index.ll b/llvm/test/DebugInfo/X86/dbg-value-frame-index.ll
index b411f20..a2cf2cc 100644
--- a/llvm/test/DebugInfo/X86/dbg-value-frame-index.ll
+++ b/llvm/test/DebugInfo/X86/dbg-value-frame-index.ll
@@ -20,10 +20,14 @@
}
; CHECK-LABEL: test
-; CHECK: #DEBUG_VALUE: test:w <- [DW_OP_plus_uconst 8] [$rsp+0]
+; To get the value of the variable, we need to do [$rsp+8], i.e:
+; CHECK: #DEBUG_VALUE: test:w <- [DW_OP_plus_uconst 8, DW_OP_deref] $rsp
; DWARF: DW_AT_location [DW_FORM_sec_offset] (
; DWARF-NEXT: [{{.*}}, {{.*}}): DW_OP_breg7 RSP+8)
+; Note: A previous version of this test checked for `[DW_OP_plus_uconst 8] [$rsp+0]`,
+; which is incorrect, because it adds the stack offset after dereferencing the stack pointer.
+
declare i1 @fn(i64*, i64*, i64*, i8*, i64, i64*, i32*, i8*)
declare void @llvm.dbg.value(metadata, metadata, metadata)
@@ -36,7 +40,7 @@
!3 = !{i32 2, !"Debug Info Version", i32 3}
!4 = distinct !DISubprogram(name: "test", type: !10, unit: !0)
!5 = !DILocalVariable(name: "w", scope: !4, type: !9)
-!6 = !DIExpression()
+!6 = !DIExpression(DW_OP_deref)
!7 = !DILocation(line: 210, column: 12, scope: !4)
!8 = !{!9}
!9 = !DIBasicType(name: "bool", size: 8, encoding: DW_ATE_boolean)
diff --git a/llvm/test/DebugInfo/X86/debug-loc-frame.ll b/llvm/test/DebugInfo/X86/debug-loc-frame.ll
index 58b1185..f3bcfcb 100644
--- a/llvm/test/DebugInfo/X86/debug-loc-frame.ll
+++ b/llvm/test/DebugInfo/X86/debug-loc-frame.ll
@@ -28,7 +28,14 @@
; CHECK: DW_TAG_variable
; CHECK: DW_AT_location [DW_FORM_sec_offset] ({{.*}}
; CHECK-NEXT: [{{0x.*}}, {{0x.*}}): DW_OP_reg0 RAX
-; CHECK-NEXT: [{{0x.*}}, {{0x.*}}): DW_OP_breg7 RSP+4, DW_OP_deref)
+;
+; Note: This is a location, so we don't want an extra DW_OP_deref at the end.
+; LLDB gets the location right without it:
+; Variable: ... name = "val", type = "int", location = [rsp+4], decl = frame.c:10
+; Adding the deref actually creates an invalid location:
+; ... [rsp+4] DW_OP_deref
+;
+; CHECK-NEXT: [{{0x.*}}, {{0x.*}}): DW_OP_breg7 RSP+4)
; CHECK-NEXT: DW_AT_name {{.*}}"val"
; ModuleID = 'frame.c'
diff --git a/llvm/test/Transforms/InstCombine/lower-dbg-declare.ll b/llvm/test/Transforms/InstCombine/lower-dbg-declare.ll
new file mode 100644
index 0000000..44de3fc
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/lower-dbg-declare.ll
@@ -0,0 +1,183 @@
+; RUN: opt -instcombine < %s -S | FileCheck %s
+
+; This tests dbg.declare lowering for CallInst users of an alloca. The
+; resulting dbg.value expressions should add a deref to the declare's expression.
+
+; Hand-reduced from this example (-g -Og -fsanitize=address):
+
+; static volatile int sink;
+; struct OneElementVector {
+; int Element;
+; OneElementVector(int Element) : Element(Element) { sink = Element; }
+; bool empty() const { return false; }
+; };
+; using container = OneElementVector;
+; static void escape(container &c) { sink = c.Element; }
+; int main() {
+; container d1 = {42};
+; while (!d1.empty())
+; escape(d1);
+; return 0;
+; }
+
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.13.0"
+
+%struct.OneElementVector = type { i32 }
+
+define i1 @escape(%struct.OneElementVector* %d1) {
+ ret i1 false
+}
+
+; CHECK-LABEL: @main
+define i32 @main() !dbg !15 {
+entry:
+ %d1 = alloca %struct.OneElementVector, align 4
+ %0 = bitcast %struct.OneElementVector* %d1 to i8*, !dbg !34
+
+; CHECK: dbg.value(metadata %struct.OneElementVector* [[var:%.*]], metadata !DIExpression(DW_OP_deref))
+; CHECK-NEXT: call i1 @escape
+ call void @llvm.dbg.declare(metadata %struct.OneElementVector* %d1, metadata !19, metadata !DIExpression()), !dbg !35
+ call i1 @escape(%struct.OneElementVector* %d1)
+ br label %while.cond, !dbg !37
+
+while.cond: ; preds = %while.body, %entry
+; CHECK: dbg.value(metadata %struct.OneElementVector* [[var]], metadata !DIExpression(DW_OP_deref))
+; CHECK-NEXT: call i1 @escape
+ %call = call i1 @escape(%struct.OneElementVector* %d1), !dbg !38
+ %lnot = xor i1 %call, true, !dbg !39
+ br i1 %lnot, label %while.body, label %while.end, !dbg !37
+
+while.body: ; preds = %while.cond
+; CHECK: dbg.value(metadata %struct.OneElementVector* [[var]], metadata !DIExpression(DW_OP_deref))
+; CHECK-NEXT: call i1 @escape
+ call i1 @escape(%struct.OneElementVector* %d1)
+ br label %while.cond, !dbg !37, !llvm.loop !42
+
+while.end: ; preds = %while.cond
+ ret i32 0, !dbg !45
+}
+
+; CHECK-LABEL: @main2
+define i32 @main2() {
+entry:
+ %d1 = alloca %struct.OneElementVector, align 4
+ %0 = bitcast %struct.OneElementVector* %d1 to i8*, !dbg !34
+
+; CHECK: dbg.value(metadata %struct.OneElementVector* [[var:%.*]], metadata !DIExpression(DW_OP_lit0, DW_OP_mul, DW_OP_deref))
+; CHECK-NEXT: call i1 @escape
+ call void @llvm.dbg.declare(metadata %struct.OneElementVector* %d1, metadata !19, metadata !DIExpression(DW_OP_lit0, DW_OP_mul)), !dbg !35
+ call i1 @escape(%struct.OneElementVector* %d1)
+ br label %while.cond, !dbg !37
+
+while.cond: ; preds = %while.body, %entry
+; CHECK: dbg.value(metadata %struct.OneElementVector* [[var]], metadata !DIExpression(DW_OP_lit0, DW_OP_mul, DW_OP_deref))
+; CHECK-NEXT: call i1 @escape
+ %call = call i1 @escape(%struct.OneElementVector* %d1), !dbg !38
+ %lnot = xor i1 %call, true, !dbg !39
+ br i1 %lnot, label %while.body, label %while.end, !dbg !37
+
+while.body: ; preds = %while.cond
+; CHECK: dbg.value(metadata %struct.OneElementVector* [[var]], metadata !DIExpression(DW_OP_lit0, DW_OP_mul, DW_OP_deref))
+; CHECK-NEXT: call i1 @escape
+ call i1 @escape(%struct.OneElementVector* %d1)
+ br label %while.cond, !dbg !37, !llvm.loop !42
+
+while.end: ; preds = %while.cond
+ ret i32 0, !dbg !45
+}
+
+declare void @llvm.dbg.declare(metadata, metadata, metadata)
+
+!llvm.dbg.cu = !{!2}
+!llvm.asan.globals = !{!8}
+!llvm.module.flags = !{!10, !11, !12, !13}
+!llvm.ident = !{!14}
+
+!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
+!1 = distinct !DIGlobalVariable(name: "sink", linkageName: "_ZL4sink", scope: !2, file: !3, line: 1, type: !6, isLocal: true, isDefinition: true)
+!2 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !3, producer: "clang version 7.0.0 (trunk 337207) (llvm/trunk 337204)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5)
+!3 = !DIFile(filename: "test.cc", directory: "/Users/vsk/src/builds/llvm.org-master-RA")
+!4 = !{}
+!5 = !{!0}
+!6 = !DIDerivedType(tag: DW_TAG_volatile_type, baseType: !7)
+!7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!8 = !{}
+!9 = !{!"test.cc", i32 1, i32 21}
+!10 = !{i32 2, !"Dwarf Version", i32 4}
+!11 = !{i32 2, !"Debug Info Version", i32 3}
+!12 = !{i32 1, !"wchar_size", i32 4}
+!13 = !{i32 7, !"PIC Level", i32 2}
+!14 = !{!"clang version 7.0.0 (trunk 337207) (llvm/trunk 337204)"}
+!15 = distinct !DISubprogram(name: "main", scope: !3, file: !3, line: 18, type: !16, isLocal: false, isDefinition: true, scopeLine: 18, flags: DIFlagPrototyped, isOptimized: true, unit: !2, retainedNodes: !18)
+!16 = !DISubroutineType(types: !17)
+!17 = !{!7}
+!18 = !{!19}
+!19 = !DILocalVariable(name: "d1", scope: !15, file: !3, line: 21, type: !20)
+!20 = !DIDerivedType(tag: DW_TAG_typedef, name: "container", file: !3, line: 12, baseType: !21)
+!21 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "OneElementVector", file: !3, line: 3, size: 32, flags: DIFlagTypePassByValue, elements: !22, identifier: "_ZTS16OneElementVector")
+!22 = !{!23, !24, !28}
+!23 = !DIDerivedType(tag: DW_TAG_member, name: "Element", scope: !21, file: !3, line: 4, baseType: !7, size: 32)
+!24 = !DISubprogram(name: "OneElementVector", scope: !21, file: !3, line: 6, type: !25, isLocal: false, isDefinition: false, scopeLine: 6, flags: DIFlagPrototyped, isOptimized: true)
+!25 = !DISubroutineType(types: !26)
+!26 = !{null, !27, !7}
+!27 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !21, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer)
+!28 = !DISubprogram(name: "empty", linkageName: "_ZNK16OneElementVector5emptyEv", scope: !21, file: !3, line: 8, type: !29, isLocal: false, isDefinition: false, scopeLine: 8, flags: DIFlagPrototyped, isOptimized: true)
+!29 = !DISubroutineType(types: !30)
+!30 = !{!31, !32}
+!31 = !DIBasicType(name: "bool", size: 8, encoding: DW_ATE_boolean)
+!32 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !33, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer)
+!33 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !21)
+!34 = !DILocation(line: 21, column: 3, scope: !15)
+!35 = !DILocation(line: 21, column: 13, scope: !15)
+!36 = !DILocation(line: 21, column: 18, scope: !15)
+!37 = !DILocation(line: 22, column: 3, scope: !15)
+!38 = !DILocation(line: 22, column: 14, scope: !15)
+!39 = !DILocation(line: 22, column: 10, scope: !15)
+!40 = !DILocation(line: 23, column: 5, scope: !41)
+!41 = distinct !DILexicalBlock(scope: !15, file: !3, line: 22, column: 23)
+!42 = distinct !{!42, !37, !43}
+!43 = !DILocation(line: 24, column: 3, scope: !15)
+!44 = !DILocation(line: 26, column: 1, scope: !15)
+!45 = !DILocation(line: 25, column: 3, scope: !15)
+!46 = distinct !DISubprogram(name: "OneElementVector", linkageName: "_ZN16OneElementVectorC1Ei", scope: !21, file: !3, line: 6, type: !25, isLocal: false, isDefinition: true, scopeLine: 6, flags: DIFlagPrototyped, isOptimized: true, unit: !2, declaration: !24, retainedNodes: !47)
+!47 = !{!48, !50}
+!48 = !DILocalVariable(name: "this", arg: 1, scope: !46, type: !49, flags: DIFlagArtificial | DIFlagObjectPointer)
+!49 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !21, size: 64)
+!50 = !DILocalVariable(name: "Element", arg: 2, scope: !46, file: !3, line: 6, type: !7)
+!51 = !DILocation(line: 0, scope: !46)
+!52 = !DILocation(line: 6, column: 24, scope: !46)
+!53 = !DILocation(line: 6, column: 52, scope: !46)
+!54 = !DILocation(line: 6, column: 70, scope: !46)
+!55 = distinct !DISubprogram(name: "empty", linkageName: "_ZNK16OneElementVector5emptyEv", scope: !21, file: !3, line: 8, type: !29, isLocal: false, isDefinition: true, scopeLine: 8, flags: DIFlagPrototyped, isOptimized: true, unit: !2, declaration: !28, retainedNodes: !56)
+!56 = !{!57}
+!57 = !DILocalVariable(name: "this", arg: 1, scope: !55, type: !58, flags: DIFlagArtificial | DIFlagObjectPointer)
+!58 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !33, size: 64)
+!59 = !DILocation(line: 0, scope: !55)
+!60 = !DILocation(line: 8, column: 24, scope: !55)
+!61 = distinct !DISubprogram(name: "escape", linkageName: "_ZL6escapeR16OneElementVector", scope: !3, file: !3, line: 14, type: !62, isLocal: true, isDefinition: true, scopeLine: 14, flags: DIFlagPrototyped, isOptimized: true, unit: !2, retainedNodes: !65)
+!62 = !DISubroutineType(types: !63)
+!63 = !{null, !64}
+!64 = !DIDerivedType(tag: DW_TAG_reference_type, baseType: !20, size: 64)
+!65 = !{!66}
+!66 = !DILocalVariable(name: "c", arg: 1, scope: !61, file: !3, line: 14, type: !64)
+!67 = !DILocation(line: 14, column: 31, scope: !61)
+!68 = !DILocation(line: 15, column: 12, scope: !61)
+!69 = !{!70, !71, i64 0}
+!70 = !{!"_ZTS16OneElementVector", !71, i64 0}
+!71 = !{!"int", !72, i64 0}
+!72 = !{!"omnipotent char", !73, i64 0}
+!73 = !{!"Simple C++ TBAA"}
+!74 = !DILocation(line: 15, column: 8, scope: !61)
+!75 = !{!71, !71, i64 0}
+!76 = !DILocation(line: 16, column: 1, scope: !61)
+!77 = distinct !DISubprogram(name: "OneElementVector", linkageName: "_ZN16OneElementVectorC2Ei", scope: !21, file: !3, line: 6, type: !25, isLocal: false, isDefinition: true, scopeLine: 6, flags: DIFlagPrototyped, isOptimized: true, unit: !2, declaration: !24, retainedNodes: !78)
+!78 = !{!79, !80}
+!79 = !DILocalVariable(name: "this", arg: 1, scope: !77, type: !49, flags: DIFlagArtificial | DIFlagObjectPointer)
+!80 = !DILocalVariable(name: "Element", arg: 2, scope: !77, file: !3, line: 6, type: !7)
+!81 = !DILocation(line: 0, scope: !77)
+!82 = !DILocation(line: 6, column: 24, scope: !77)
+!83 = !DILocation(line: 6, column: 35, scope: !77)
+!84 = !DILocation(line: 6, column: 59, scope: !85)
+!85 = distinct !DILexicalBlock(scope: !77, file: !3, line: 6, column: 52)
+!86 = !DILocation(line: 6, column: 70, scope: !77)