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Differential D67102

DWARF: Fix a regression in location list dumping
ClosedPublic

Authored by labath on Sep 3 2019, 8:13 AM.

Details

Reviewers
JDevlieghere
dblaikie
probinson
Commits
rG88b4e28a679a: DWARF: Fix a regression in location list dumping
rL370868: DWARF: Fix a regression in location list dumping
Summary

While fixing the handling of some error cases, r370363 introduced new
problems -- assertion failures due to unchecked errors (my excuse is that a very
early version of that patch used Optional<T> instead of Expected).

This patch adds proper handling of parsing errors encountered when
dumping location lists from inside DWARF DIEs, and adds a bunch of
additional tests.

I reorder the arguments of the location list dumping functions to make
them consistent, and also be able to dump the two kinds of location
lists generically.

Diff Detail

Repository
rL LLVM

Event Timeline

labath created this revision.Sep 3 2019, 8:13 AM
Herald added a project: Restricted Project. · View Herald TranscriptSep 3 2019, 8:13 AM
Herald added a subscriber: aprantl. · View Herald Transcript
Harbormaster completed remote builds in B37662: Diff 218459.Sep 3 2019, 8:14 AM
JDevlieghere accepted this revision.Sep 3 2019, 9:29 AM

LGTM

This revision is now accepted and ready to land.Sep 3 2019, 9:29 AM
Closed by commit rL370868: DWARF: Fix a regression in location list dumping (authored by labath). · Explain WhySep 4 2019, 3:07 AM
This revision was automatically updated to reflect the committed changes.

Revision Contents

PathSize
llvm/
trunk/
include/
llvm/
DebugInfo/
DWARF/
4 lines
lib/
DebugInfo/
DWARF/
9 lines
39 lines
test/
DebugInfo/
X86/
121 lines
132 lines

Diff 218629

llvm/trunk/include/llvm/DebugInfo/DWARF/DWARFDebugLoc.h

Show All 34 Linespublic:
/// A list of locations that contain one variable. /// A list of locations that contain one variable.
struct LocationList { struct LocationList {
/// The beginning offset where this location list is stored in the debug_loc /// The beginning offset where this location list is stored in the debug_loc
/// section. /// section.
uint64_t Offset; uint64_t Offset;
/// All the locations in which the variable is stored. /// All the locations in which the variable is stored.
SmallVector<Entry, 2> Entries; SmallVector<Entry, 2> Entries;
/// Dump this list on OS. /// Dump this list on OS.
void dump(raw_ostream &OS, bool IsLittleEndian, unsigned AddressSize, void dump(raw_ostream &OS, uint64_t BaseAddress, bool IsLittleEndian,
const MCRegisterInfo *MRI, DWARFUnit *U, uint64_t BaseAddress, unsigned AddressSize, const MCRegisterInfo *MRI, DWARFUnit *U,
unsigned Indent) const; unsigned Indent) const;
}; };
private: private:
using LocationLists = SmallVector<LocationList, 4>; using LocationLists = SmallVector<LocationList, 4>;
/// A list of all the variables in the debug_loc section, each one describing /// A list of all the variables in the debug_loc section, each one describing
/// the locations in which the variable is stored. /// the locations in which the variable is stored.
▲ Show 20 Lines • Show All 64 Lines • Show Last 20 Lines

llvm/trunk/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp

Show All 29 Lines
// non-LLVM tools. // non-LLVM tools.
static void dumpExpression(raw_ostream &OS, ArrayRef<uint8_t> Data, static void dumpExpression(raw_ostream &OS, ArrayRef<uint8_t> Data,
bool IsLittleEndian, unsigned AddressSize, bool IsLittleEndian, unsigned AddressSize,
const MCRegisterInfo *MRI, DWARFUnit *U) { const MCRegisterInfo *MRI, DWARFUnit *U) {
DWARFDataExtractor Extractor(toStringRef(Data), IsLittleEndian, AddressSize); DWARFDataExtractor Extractor(toStringRef(Data), IsLittleEndian, AddressSize);
DWARFExpression(Extractor, dwarf::DWARF_VERSION, AddressSize).print(OS, MRI, U); DWARFExpression(Extractor, dwarf::DWARF_VERSION, AddressSize).print(OS, MRI, U);
} }
void DWARFDebugLoc::LocationList::dump(raw_ostream &OS, bool IsLittleEndian, void DWARFDebugLoc::LocationList::dump(raw_ostream &OS, uint64_t BaseAddress,
bool IsLittleEndian,
unsigned AddressSize, unsigned AddressSize,
const MCRegisterInfo *MRI, const MCRegisterInfo *MRI, DWARFUnit *U,
DWARFUnit *U,
uint64_t BaseAddress,
unsigned Indent) const { unsigned Indent) const {
for (const Entry &E : Entries) { for (const Entry &E : Entries) {
OS << '\n'; OS << '\n';
OS.indent(Indent); OS.indent(Indent);
OS << format("[0x%*.*" PRIx64 ", ", AddressSize * 2, AddressSize * 2, OS << format("[0x%*.*" PRIx64 ", ", AddressSize * 2, AddressSize * 2,
BaseAddress + E.Begin); BaseAddress + E.Begin);
OS << format(" 0x%*.*" PRIx64 ")", AddressSize * 2, AddressSize * 2, OS << format(" 0x%*.*" PRIx64 ")", AddressSize * 2, AddressSize * 2,
BaseAddress + E.End); BaseAddress + E.End);
Show All 11 Lines if (It != Locations.end() && It->Offset == Offset)
return &(*It); return &(*It);
return nullptr; return nullptr;
} }
void DWARFDebugLoc::dump(raw_ostream &OS, const MCRegisterInfo *MRI, void DWARFDebugLoc::dump(raw_ostream &OS, const MCRegisterInfo *MRI,
Optional<uint64_t> Offset) const { Optional<uint64_t> Offset) const {
auto DumpLocationList = [&](const LocationList &L) { auto DumpLocationList = [&](const LocationList &L) {
OS << format("0x%8.8" PRIx64 ": ", L.Offset); OS << format("0x%8.8" PRIx64 ": ", L.Offset);
L.dump(OS, IsLittleEndian, AddressSize, MRI, nullptr, 0, 12); L.dump(OS, 0, IsLittleEndian, AddressSize, MRI, nullptr, 12);
OS << "\n\n"; OS << "\n\n";
}; };
if (Offset) { if (Offset) {
if (auto *L = getLocationListAtOffset(*Offset)) if (auto *L = getLocationListAtOffset(*Offset))
DumpLocationList(*L); DumpLocationList(*L);
return; return;
} }
▲ Show 20 Lines • Show All 189 Lines • Show Last 20 Lines

llvm/trunk/lib/DebugInfo/DWARF/DWARFDie.cpp

Show All 15 Lines
#include "llvm/DebugInfo/DWARF/DWARFContext.h" #include "llvm/DebugInfo/DWARF/DWARFContext.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugRangeList.h" #include "llvm/DebugInfo/DWARF/DWARFDebugRangeList.h"
#include "llvm/DebugInfo/DWARF/DWARFExpression.h" #include "llvm/DebugInfo/DWARF/DWARFExpression.h"
#include "llvm/DebugInfo/DWARF/DWARFFormValue.h" #include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
#include "llvm/DebugInfo/DWARF/DWARFUnit.h" #include "llvm/DebugInfo/DWARF/DWARFUnit.h"
#include "llvm/Object/ObjectFile.h" #include "llvm/Object/ObjectFile.h"
#include "llvm/Support/DataExtractor.h" #include "llvm/Support/DataExtractor.h"
#include "llvm/Support/Format.h" #include "llvm/Support/Format.h"
#include "llvm/Support/FormatAdapters.h"
#include "llvm/Support/FormatVariadic.h" #include "llvm/Support/FormatVariadic.h"
#include "llvm/Support/MathExtras.h" #include "llvm/Support/MathExtras.h"
#include "llvm/Support/WithColor.h" #include "llvm/Support/WithColor.h"
#include "llvm/Support/raw_ostream.h" #include "llvm/Support/raw_ostream.h"
#include <algorithm> #include <algorithm>
#include <cassert> #include <cassert>
#include <cinttypes> #include <cinttypes>
#include <cstdint> #include <cstdint>
▲ Show 20 Lines • Show All 54 Lines • ▼ Show 20 Lines if (FormValue.isFormClass(DWARFFormValue::FC_Block) ||
DataExtractor Data(StringRef((const char *)Expr.data(), Expr.size()), DataExtractor Data(StringRef((const char *)Expr.data(), Expr.size()),
Ctx.isLittleEndian(), 0); Ctx.isLittleEndian(), 0);
DWARFExpression(Data, U->getVersion(), U->getAddressByteSize()) DWARFExpression(Data, U->getVersion(), U->getAddressByteSize())
.print(OS, MRI, U); .print(OS, MRI, U);
return; return;
} }
FormValue.dump(OS, DumpOpts); FormValue.dump(OS, DumpOpts);
const auto &DumpLL = [&](auto ExpectedLL) {
if (ExpectedLL) {
uint64_t BaseAddr = 0;
if (Optional<object::SectionedAddress> BA = U->getBaseAddress())
BaseAddr = BA->Address;
ExpectedLL->dump(OS, BaseAddr, Ctx.isLittleEndian(), Obj.getAddressSize(),
MRI, U, Indent);
} else {
OS << '\n';
OS.indent(Indent);
OS << formatv("error extracting location list: {0}",
fmt_consume(ExpectedLL.takeError()));
}
};
if (FormValue.isFormClass(DWARFFormValue::FC_SectionOffset)) { if (FormValue.isFormClass(DWARFFormValue::FC_SectionOffset)) {
uint64_t Offset = *FormValue.getAsSectionOffset(); uint64_t Offset = *FormValue.getAsSectionOffset();
if (!U->isDWOUnit() && !U->getLocSection()->Data.empty()) { if (!U->isDWOUnit() && !U->getLocSection()->Data.empty()) {
DWARFDebugLoc DebugLoc; DWARFDebugLoc DebugLoc;
DWARFDataExtractor Data(Obj, *U->getLocSection(), Ctx.isLittleEndian(), DWARFDataExtractor Data(Obj, *U->getLocSection(), Ctx.isLittleEndian(),
Obj.getAddressSize()); Obj.getAddressSize());
auto LL = DebugLoc.parseOneLocationList(Data, &Offset); DumpLL(DebugLoc.parseOneLocationList(Data, &Offset));
if (LL) {
uint64_t BaseAddr = 0;
if (Optional<object::SectionedAddress> BA = U->getBaseAddress())
BaseAddr = BA->Address;
LL->dump(OS, Ctx.isLittleEndian(), Obj.getAddressSize(), MRI, U,
BaseAddr, Indent);
} else
OS << "error extracting location list.";
return; return;
} }
bool UseLocLists = !U->isDWOUnit(); bool UseLocLists = !U->isDWOUnit();
StringRef LoclistsSectionData = StringRef LoclistsSectionData =
UseLocLists ? Obj.getLoclistsSection().Data : U->getLocSectionData(); UseLocLists ? Obj.getLoclistsSection().Data : U->getLocSectionData();
if (!LoclistsSectionData.empty()) { if (!LoclistsSectionData.empty()) {
DataExtractor Data(LoclistsSectionData, Ctx.isLittleEndian(), DataExtractor Data(LoclistsSectionData, Ctx.isLittleEndian(),
Obj.getAddressSize()); Obj.getAddressSize());
// Old-style location list were used in DWARF v4 (.debug_loc.dwo section). // Old-style location list were used in DWARF v4 (.debug_loc.dwo section).
// Modern locations list (.debug_loclists) are used starting from v5. // Modern locations list (.debug_loclists) are used starting from v5.
// Ideally we should take the version from the .debug_loclists section // Ideally we should take the version from the .debug_loclists section
// header, but using CU's version for simplicity. // header, but using CU's version for simplicity.
auto LL = DWARFDebugLoclists::parseOneLocationList( DumpLL(DWARFDebugLoclists::parseOneLocationList(
Data, &Offset, UseLocLists ? U->getVersion() : 4); Data, &Offset, UseLocLists ? U->getVersion() : 4));
uint64_t BaseAddr = 0;
if (Optional<object::SectionedAddress> BA = U->getBaseAddress())
BaseAddr = BA->Address;
if (LL)
LL->dump(OS, BaseAddr, Ctx.isLittleEndian(), Obj.getAddressSize(), MRI,
U, Indent);
else
OS << "error extracting location list.";
} }
} }
} }
/// Dump the name encoded in the type tag. /// Dump the name encoded in the type tag.
static void dumpTypeTagName(raw_ostream &OS, dwarf::Tag T) { static void dumpTypeTagName(raw_ostream &OS, dwarf::Tag T) {
StringRef TagStr = TagString(T); StringRef TagStr = TagString(T);
if (!TagStr.startswith("DW_TAG_") || !TagStr.endswith("_type")) if (!TagStr.startswith("DW_TAG_") || !TagStr.endswith("_type"))
▲ Show 20 Lines • Show All 598 Lines • Show Last 20 Lines

llvm/trunk/test/DebugInfo/X86/dwarfdump-debug-loc-error-cases2.s

# RUN: llvm-mc -triple=x86_64-pc-linux -filetype=obj %s > %t
# RUN: llvm-dwarfdump %t | FileCheck %s
# CHECK: DW_AT_name ("x0")
# CHECK-NEXT: DW_AT_location (0x00000000
# CHECK-NEXT: [0x0000000000000000, 0x0000000000000002): DW_OP_reg5 RDI
# CHECK-NEXT: [0x0000000000000002, 0x0000000000000003): DW_OP_reg0 RAX)
# CHECK: DW_AT_name ("x1")
# CHECK-NEXT: DW_AT_location (0xdeadbeef
# CHECK-NEXT: error extracting location list: unexpected end of data)
# CHECK: DW_AT_name ("x2")
# CHECK-NEXT: DW_AT_location (0x00000036
# CHECK-NEXT: error extracting location list: unexpected end of data)
.type f,@function
f: # @f
.Lfunc_begin0:
movl %edi, %eax
.Ltmp0:
retq
.Ltmp1:
.Lfunc_end0:
.size f, .Lfunc_end0-f
.section .debug_str,"MS",@progbits,1
.Linfo_string0:
.asciz "Hand-written DWARF"
.Linfo_string3:
.asciz "f"
.Linfo_string4:
.asciz "int"
.Lx0:
.asciz "x0"
.Lx1:
.asciz "x1"
.Lx2:
.asciz "x2"
.section .debug_loc,"",@progbits
.Ldebug_loc0:
.quad .Lfunc_begin0-.Lfunc_begin0
.quad .Ltmp0-.Lfunc_begin0
.short 1 # Loc expr size
.byte 85 # super-register DW_OP_reg5
.quad .Ltmp0-.Lfunc_begin0
.quad .Lfunc_end0-.Lfunc_begin0
.short 1 # Loc expr size
.byte 80 # super-register DW_OP_reg0
.quad 0
.quad 0
.Ldebug_loc2:
.quad .Lfunc_begin0-.Lfunc_begin0
.quad .Lfunc_end0-.Lfunc_begin0
.short 0xdead # Loc expr size
.section .debug_abbrev,"",@progbits
.byte 1 # Abbreviation Code
.byte 17 # DW_TAG_compile_unit
.byte 1 # DW_CHILDREN_yes
.byte 37 # DW_AT_producer
.byte 14 # DW_FORM_strp
.byte 19 # DW_AT_language
.byte 5 # DW_FORM_data2
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 2 # Abbreviation Code
.byte 46 # DW_TAG_subprogram
.byte 1 # DW_CHILDREN_yes
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 3 # Abbreviation Code
.byte 5 # DW_TAG_formal_parameter
.byte 0 # DW_CHILDREN_no
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 2 # DW_AT_location
.byte 23 # DW_FORM_sec_offset
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 4 # Abbreviation Code
.byte 36 # DW_TAG_base_type
.byte 0 # DW_CHILDREN_no
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 62 # DW_AT_encoding
.byte 11 # DW_FORM_data1
.byte 11 # DW_AT_byte_size
.byte 11 # DW_FORM_data1
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 0 # EOM(3)
.section .debug_info,"",@progbits
.Lcu_begin0:
.long .Ldebug_info_end0-.Ldebug_info_start0 # Length of Unit
.Ldebug_info_start0:
.short 4 # DWARF version number
.long .debug_abbrev # Offset Into Abbrev. Section
.byte 8 # Address Size (in bytes)
.byte 1 # Abbrev [1] 0xb:0x50 DW_TAG_compile_unit
.long .Linfo_string0 # DW_AT_producer
.short 12 # DW_AT_language
.byte 2 # Abbrev [2] 0x2a:0x29 DW_TAG_subprogram
.long .Linfo_string3 # DW_AT_name
.byte 3 # Abbrev [3] DW_TAG_formal_parameter
.long .Lx0 # DW_AT_name
.long .Ldebug_loc0 # DW_AT_location
.byte 3 # Abbrev [3] DW_TAG_formal_parameter
.long .Lx1 # DW_AT_name
.long 0xdeadbeef # DW_AT_location
.byte 3 # Abbrev [3] DW_TAG_formal_parameter
.long .Lx2 # DW_AT_name
.long .Ldebug_loc2 # DW_AT_location
.byte 0 # End Of Children Mark
.byte 0 # End Of Children Mark
.Ldebug_info_end0:

llvm/trunk/test/DebugInfo/X86/dwarfdump-debug-loclists-error-cases2.s

# RUN: llvm-mc -triple=x86_64-pc-linux -filetype=obj %s > %t
# RUN: llvm-dwarfdump %t | FileCheck %s
# CHECK: DW_AT_name ("x0")
# CHECK-NEXT: DW_AT_location (0x0000000c
# CHECK-NEXT: [0x0000000000000000, 0x0000000000000002): DW_OP_reg5 RDI
# CHECK-NEXT: [0x0000000000000002, 0x0000000000000003): DW_OP_reg0 RAX)
# CHECK: DW_AT_name ("x1")
# CHECK-NEXT: DW_AT_location (0xdeadbeef
# CHECK-NEXT: error extracting location list: unexpected end of data)
# CHECK: DW_AT_name ("x2")
# CHECK-NEXT: DW_AT_location (0x00000025
# CHECK-NEXT: error extracting location list: unexpected end of data)
.type f,@function
f: # @f
.Lfunc_begin0:
movl %edi, %eax
.Ltmp0:
retq
.Ltmp1:
.Lfunc_end0:
.size f, .Lfunc_end0-f
.section .debug_str,"MS",@progbits,1
.Linfo_string0:
.asciz "Hand-written DWARF"
.Linfo_string3:
.asciz "f"
.Linfo_string4:
.asciz "int"
.Lx0:
.asciz "x0"
.Lx1:
.asciz "x1"
.Lx2:
.asciz "x2"
.section .debug_loclists,"",@progbits
.long .Ldebug_loclist_table_end0-.Ldebug_loclist_table_start0 # Length
.Ldebug_loclist_table_start0:
.short 5 # Version
.byte 8 # Address size
.byte 0 # Segment selector size
.long 0 # Offset entry count
.Lloclists_table_base0:
.Ldebug_loc0:
.byte 8 # DW_LLE_start_length
.quad .Lfunc_begin0-.Lfunc_begin0 # starting offset
.uleb128 .Ltmp0-.Lfunc_begin0 # size
.byte 1 # Loc expr size
.byte 85 # super-register DW_OP_reg5
.byte 8 # DW_LLE_start_length
.quad .Ltmp0-.Lfunc_begin0 # starting offset
.uleb128 .Lfunc_end0-.Ltmp0 # size
.byte 1 # Loc expr size
.byte 80 # super-register DW_OP_reg0
.byte 0 # DW_LLE_end_of_list
.Ldebug_loc2:
.byte 8 # DW_LLE_start_length
.quad .Lfunc_begin0-.Lfunc_begin0 # starting offset
.uleb128 .Ltmp0-.Lfunc_begin0 # size
.uleb128 0xdeadbeef # Loc expr size
.Ldebug_loclist_table_end0:
.section .debug_abbrev,"",@progbits
.byte 1 # Abbreviation Code
.byte 17 # DW_TAG_compile_unit
.byte 1 # DW_CHILDREN_yes
.byte 37 # DW_AT_producer
.byte 14 # DW_FORM_strp
.byte 19 # DW_AT_language
.byte 5 # DW_FORM_data2
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 2 # Abbreviation Code
.byte 46 # DW_TAG_subprogram
.byte 1 # DW_CHILDREN_yes
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 3 # Abbreviation Code
.byte 5 # DW_TAG_formal_parameter
.byte 0 # DW_CHILDREN_no
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 2 # DW_AT_location
.byte 23 # DW_FORM_sec_offset
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 4 # Abbreviation Code
.byte 36 # DW_TAG_base_type
.byte 0 # DW_CHILDREN_no
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 62 # DW_AT_encoding
.byte 11 # DW_FORM_data1
.byte 11 # DW_AT_byte_size
.byte 11 # DW_FORM_data1
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 0 # EOM(3)
.section .debug_info,"",@progbits
.Lcu_begin0:
.long .Ldebug_info_end0-.Ldebug_info_start0 # Length of Unit
.Ldebug_info_start0:
.short 5 # DWARF version number
.byte 1 # DWARF Unit Type
.byte 8 # Address Size (in bytes)
.long .debug_abbrev # Offset Into Abbrev. Section
.byte 1 # Abbrev [1] 0xb:0x50 DW_TAG_compile_unit
.long .Linfo_string0 # DW_AT_producer
.short 12 # DW_AT_language
.byte 2 # Abbrev [2] 0x2a:0x29 DW_TAG_subprogram
.long .Linfo_string3 # DW_AT_name
.byte 3 # Abbrev [3] DW_TAG_formal_parameter
.long .Lx0 # DW_AT_name
.long .Ldebug_loc0 # DW_AT_location
.byte 3 # Abbrev [3] DW_TAG_formal_parameter
.long .Lx1 # DW_AT_name
.long 0xdeadbeef # DW_AT_location
.byte 3 # Abbrev [3] DW_TAG_formal_parameter
.long .Lx2 # DW_AT_name
.long .Ldebug_loc2 # DW_AT_location
.byte 0 # End Of Children Mark
.byte 0 # End Of Children Mark
.Ldebug_info_end0: