[llvm] r237721 - [DWARF parser] Add basic support for DWZ DWARF multifile extensions.
Alexey Samsonov
vonosmas at gmail.com
Tue May 19 13:29:29 PDT 2015
Author: samsonov
Date: Tue May 19 15:29:28 2015
New Revision: 237721
URL: http://llvm.org/viewvc/llvm-project?rev=237721&view=rev
Log:
[DWARF parser] Add basic support for DWZ DWARF multifile extensions.
This change implements basic support for DWARF alternate sections
proposal: http://www.dwarfstd.org/ShowIssue.php?issue=120604.1&type=open
LLVM tools now understand new forms: DW_FORM_GNU_ref_alt and
DW_FORM_GNU_strp_alt, which are used as references to .debug_info and
.debug_str sections respectively, stored in a separate file, and
possibly shared between different executables / shared objects.
llvm-dwarfdump and llvm-symbolizer don't yet know how to access this
alternate debug file (usually pointed by .gnu_debugaltlink section),
but they can at lease properly parse and dump regular files, which
refer to it.
This change should fix crashes of llvm-dwarfdump and llvm-symbolizer on
files produced by running "dwz" tool. Such files are already installed
on some modern Linux distributions.
Added:
llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test-dwz.elf-x86-64 (with props)
llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test.elf-x86-64.dwz
llvm/trunk/test/DebugInfo/dwarfdump-dwz.test
Modified:
llvm/trunk/include/llvm/DebugInfo/DWARF/DWARFFormValue.h
llvm/trunk/include/llvm/Support/Dwarf.h
llvm/trunk/lib/DebugInfo/DWARF/DWARFDebugInfoEntry.cpp
llvm/trunk/lib/DebugInfo/DWARF/DWARFFormValue.cpp
llvm/trunk/lib/Support/Dwarf.cpp
llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test.cc
Modified: llvm/trunk/include/llvm/DebugInfo/DWARF/DWARFFormValue.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/DebugInfo/DWARF/DWARFFormValue.h?rev=237721&r1=237720&r2=237721&view=diff
==============================================================================
--- llvm/trunk/include/llvm/DebugInfo/DWARF/DWARFFormValue.h (original)
+++ llvm/trunk/include/llvm/DebugInfo/DWARF/DWARFFormValue.h Tue May 19 15:29:28 2015
@@ -87,6 +87,8 @@ public:
static ArrayRef<uint8_t> getFixedFormSizes(uint8_t AddrSize,
uint16_t Version);
+private:
+ void dumpString(raw_ostream &OS, const DWARFUnit *U) const;
};
}
Modified: llvm/trunk/include/llvm/Support/Dwarf.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Support/Dwarf.h?rev=237721&r1=237720&r2=237721&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Support/Dwarf.h (original)
+++ llvm/trunk/include/llvm/Support/Dwarf.h Tue May 19 15:29:28 2015
@@ -285,7 +285,11 @@ enum Form : uint16_t {
// Extensions for Fission proposal
DW_FORM_GNU_addr_index = 0x1f01,
- DW_FORM_GNU_str_index = 0x1f02
+ DW_FORM_GNU_str_index = 0x1f02,
+
+ // Alternate debug sections proposal (output of "dwz" tool).
+ DW_FORM_GNU_ref_alt = 0x1f20,
+ DW_FORM_GNU_strp_alt = 0x1f21
};
enum LocationAtom {
Modified: llvm/trunk/lib/DebugInfo/DWARF/DWARFDebugInfoEntry.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/DebugInfo/DWARF/DWARFDebugInfoEntry.cpp?rev=237721&r1=237720&r2=237721&view=diff
==============================================================================
--- llvm/trunk/lib/DebugInfo/DWARF/DWARFDebugInfoEntry.cpp (original)
+++ llvm/trunk/lib/DebugInfo/DWARF/DWARFDebugInfoEntry.cpp Tue May 19 15:29:28 2015
@@ -161,14 +161,15 @@ void DWARFDebugInfoEntryMinimal::dumpAtt
// We have dumped the attribute raw value. For some attributes
// having both the raw value and the pretty-printed value is
// interesting. These attributes are handled below.
- if ((attr == DW_AT_specification || attr == DW_AT_abstract_origin) &&
- // The signature references aren't handled.
- formValue.getForm() != DW_FORM_ref_sig8) {
- uint32_t Ref = formValue.getAsReference(u).getValue();
- DWARFDebugInfoEntryMinimal DIE;
- if (const DWARFUnit *RefU = findUnitAndExtractFast(DIE, u, &Ref))
- if (const char *Ref = DIE.getName(RefU, DINameKind::LinkageName))
- OS << " \"" << Ref << '\"';
+ if (attr == DW_AT_specification || attr == DW_AT_abstract_origin) {
+ Optional<uint64_t> Ref = formValue.getAsReference(u);
+ if (Ref.hasValue()) {
+ uint32_t RefOffset = Ref.getValue();
+ DWARFDebugInfoEntryMinimal DIE;
+ if (const DWARFUnit *RefU = findUnitAndExtractFast(DIE, u, &RefOffset))
+ if (const char *Name = DIE.getName(RefU, DINameKind::LinkageName))
+ OS << " \"" << Name << '\"';
+ }
} else if (attr == DW_AT_APPLE_property_attribute) {
if (Optional<uint64_t> OptVal = formValue.getAsUnsignedConstant())
dumpApplePropertyAttribute(OS, *OptVal);
Modified: llvm/trunk/lib/DebugInfo/DWARF/DWARFFormValue.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/DebugInfo/DWARF/DWARFFormValue.cpp?rev=237721&r1=237720&r2=237721&view=diff
==============================================================================
--- llvm/trunk/lib/DebugInfo/DWARF/DWARFFormValue.cpp (original)
+++ llvm/trunk/lib/DebugInfo/DWARF/DWARFFormValue.cpp Tue May 19 15:29:28 2015
@@ -113,14 +113,17 @@ bool DWARFFormValue::isFormClass(DWARFFo
if (Form < ArrayRef<FormClass>(DWARF4FormClasses).size() &&
DWARF4FormClasses[Form] == FC)
return true;
- // Check DW_FORM_ref_sig8 from DWARF4.
- if (Form == DW_FORM_ref_sig8)
+ // Check more forms from DWARF4 and DWARF5 proposals.
+ switch (Form) {
+ case DW_FORM_ref_sig8:
+ case DW_FORM_GNU_ref_alt:
return (FC == FC_Reference);
- // Check for some DWARF5 forms.
- if (Form == DW_FORM_GNU_addr_index)
+ case DW_FORM_GNU_addr_index:
return (FC == FC_Address);
- if (Form == DW_FORM_GNU_str_index)
+ case DW_FORM_GNU_str_index:
+ case DW_FORM_GNU_strp_alt:
return (FC == FC_String);
+ }
// In DWARF3 DW_FORM_data4 and DW_FORM_data8 served also as a section offset.
// Don't check for DWARF version here, as some producers may still do this
// by mistake.
@@ -199,15 +202,6 @@ bool DWARFFormValue::extractValue(DataEx
case DW_FORM_sdata:
Value.sval = data.getSLEB128(offset_ptr);
break;
- case DW_FORM_strp: {
- Value.uval = data.getU32(offset_ptr);
- if (!cu)
- break;
- RelocAddrMap::const_iterator AI = cu->getRelocMap()->find(*offset_ptr-4);
- if (AI != cu->getRelocMap()->end())
- Value.uval += AI->second.second;
- break;
- }
case DW_FORM_udata:
case DW_FORM_ref_udata:
Value.uval = data.getULEB128(offset_ptr);
@@ -219,14 +213,18 @@ bool DWARFFormValue::extractValue(DataEx
Form = data.getULEB128(offset_ptr);
indirect = true;
break;
- case DW_FORM_sec_offset: {
+ case DW_FORM_sec_offset:
+ case DW_FORM_strp:
+ case DW_FORM_GNU_ref_alt:
+ case DW_FORM_GNU_strp_alt: {
// FIXME: This is 64-bit for DWARF64.
Value.uval = data.getU32(offset_ptr);
if (!cu)
break;
- RelocAddrMap::const_iterator AI = cu->getRelocMap()->find(*offset_ptr-4);
+ RelocAddrMap::const_iterator AI =
+ cu->getRelocMap()->find(*offset_ptr - 4);
if (AI != cu->getRelocMap()->end())
- Value.uval += AI->second.second;
+ Value.uval += AI->second.second;
break;
}
case DW_FORM_flag_present:
@@ -323,7 +321,6 @@ DWARFFormValue::skipValue(uint16_t form,
return true;
// 4 byte values
- case DW_FORM_strp:
case DW_FORM_data4:
case DW_FORM_ref4:
*offset_ptr += 4;
@@ -353,6 +350,9 @@ DWARFFormValue::skipValue(uint16_t form,
// FIXME: 4 for DWARF32, 8 for DWARF64.
case DW_FORM_sec_offset:
+ case DW_FORM_strp:
+ case DW_FORM_GNU_ref_alt:
+ case DW_FORM_GNU_strp_alt:
*offset_ptr += 4;
return true;
@@ -424,24 +424,17 @@ DWARFFormValue::dump(raw_ostream &OS, co
case DW_FORM_udata: OS << Value.uval; break;
case DW_FORM_strp: {
OS << format(" .debug_str[0x%8.8x] = ", (uint32_t)uvalue);
- Optional<const char *> DbgStr = getAsCString(cu);
- if (DbgStr.hasValue()) {
- raw_ostream &COS = WithColor(OS, syntax::String);
- COS << '"';
- COS.write_escaped(DbgStr.getValue());
- COS << '"';
- }
+ dumpString(OS, cu);
break;
}
case DW_FORM_GNU_str_index: {
OS << format(" indexed (%8.8x) string = ", (uint32_t)uvalue);
- Optional<const char *> DbgStr = getAsCString(cu);
- if (DbgStr.hasValue()) {
- raw_ostream &COS = WithColor(OS, syntax::String);
- COS << '"';
- COS.write_escaped(DbgStr.getValue());
- COS << '"';
- }
+ dumpString(OS, cu);
+ break;
+ }
+ case DW_FORM_GNU_strp_alt: {
+ OS << format("alt indirect string, offset: 0x%" PRIx64 "", uvalue);
+ dumpString(OS, cu);
break;
}
case DW_FORM_ref_addr:
@@ -467,6 +460,9 @@ DWARFFormValue::dump(raw_ostream &OS, co
cu_relative_offset = true;
OS << format("cu + 0x%" PRIx64, uvalue);
break;
+ case DW_FORM_GNU_ref_alt:
+ OS << format("<alt 0x%" PRIx64 ">", uvalue);
+ break;
// All DW_FORM_indirect attributes should be resolved prior to calling
// this function
@@ -492,12 +488,23 @@ DWARFFormValue::dump(raw_ostream &OS, co
}
}
+void DWARFFormValue::dumpString(raw_ostream &OS, const DWARFUnit *U) const {
+ Optional<const char *> DbgStr = getAsCString(U);
+ if (DbgStr.hasValue()) {
+ raw_ostream &COS = WithColor(OS, syntax::String);
+ COS << '"';
+ COS.write_escaped(DbgStr.getValue());
+ COS << '"';
+ }
+}
+
Optional<const char *> DWARFFormValue::getAsCString(const DWARFUnit *U) const {
if (!isFormClass(FC_String))
return None;
if (Form == DW_FORM_string)
return Value.cstr;
- if (!U)
+ // FIXME: Add support for DW_FORM_GNU_strp_alt
+ if (Form == DW_FORM_GNU_strp_alt || U == nullptr)
return None;
uint32_t Offset = Value.uval;
if (Form == DW_FORM_GNU_str_index) {
@@ -539,9 +546,9 @@ Optional<uint64_t> DWARFFormValue::getAs
return Value.uval + U->getOffset();
case DW_FORM_ref_addr:
return Value.uval;
- // FIXME: Add proper support for DW_FORM_ref_sig8
+ // FIXME: Add proper support for DW_FORM_ref_sig8 and DW_FORM_GNU_ref_alt.
default:
- return Value.uval;
+ return None;
}
}
Modified: llvm/trunk/lib/Support/Dwarf.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/Dwarf.cpp?rev=237721&r1=237720&r2=237721&view=diff
==============================================================================
--- llvm/trunk/lib/Support/Dwarf.cpp (original)
+++ llvm/trunk/lib/Support/Dwarf.cpp Tue May 19 15:29:28 2015
@@ -233,6 +233,10 @@ const char *llvm::dwarf::FormEncodingStr
// DWARF5 Fission Extension Forms
case DW_FORM_GNU_addr_index: return "DW_FORM_GNU_addr_index";
case DW_FORM_GNU_str_index: return "DW_FORM_GNU_str_index";
+
+ // Alternate debug sections proposal (output of "dwz" tool).
+ case DW_FORM_GNU_ref_alt: return "DW_FORM_GNU_ref_alt";
+ case DW_FORM_GNU_strp_alt: return "DW_FORM_GNU_strp_alt";
}
return nullptr;
}
Added: llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test-dwz.elf-x86-64
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test-dwz.elf-x86-64?rev=237721&view=auto
==============================================================================
Binary files llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test-dwz.elf-x86-64 (added) and llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test-dwz.elf-x86-64 Tue May 19 15:29:28 2015 differ
Propchange: llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test-dwz.elf-x86-64
------------------------------------------------------------------------------
svn:executable = *
Modified: llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test.cc
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test.cc?rev=237721&r1=237720&r2=237721&view=diff
==============================================================================
--- llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test.cc (original)
+++ llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test.cc Tue May 19 15:29:28 2015
@@ -21,3 +21,9 @@ int main() {
// $ cp dwarfdump-test.cc /tmp/dbginfo
// $ cd /tmp/dbginfo
// $ clang++ -g dwarfdump-test.cc -o <output>
+
+// The result is also used as an input to .dwz tool:
+// $ cp <output> output1.dwz
+// $ cp <output> output2.dwz
+// $ dwz -m output.dwz -r output1.dwz output2.dwz
+// $ rm output2.dwz
Added: llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test.elf-x86-64.dwz
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test.elf-x86-64.dwz?rev=237721&view=auto
==============================================================================
Binary files llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test.elf-x86-64.dwz (added) and llvm/trunk/test/DebugInfo/Inputs/dwarfdump-test.elf-x86-64.dwz Tue May 19 15:29:28 2015 differ
Added: llvm/trunk/test/DebugInfo/dwarfdump-dwz.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/dwarfdump-dwz.test?rev=237721&view=auto
==============================================================================
--- llvm/trunk/test/DebugInfo/dwarfdump-dwz.test (added)
+++ llvm/trunk/test/DebugInfo/dwarfdump-dwz.test Tue May 19 15:29:28 2015
@@ -0,0 +1,14 @@
+; RUN: llvm-dwarfdump %p/Inputs/dwarfdump-test-dwz.elf-x86-64 -debug-dump=info | FileCheck %s -check-prefix DUMP_INFO
+
+; DUMP_INFO: .debug_info
+; DUMP_INFO: DW_TAG_compile_unit [2] *
+; DUMP_INFO-NEXT: DW_AT_producer [DW_FORM_GNU_strp_alt] (alt indirect string, offset: 0x0)
+; DUMP_INFO-NEXT: DW_AT_language [DW_FORM_data2] (DW_LANG_C_plus_plus)
+; DUMP_INFO-NEXT: DW_AT_name [DW_FORM_GNU_strp_alt] (alt indirect string, offset: 0x31)
+; DUMP_INFO-NEXT: DW_AT_low_pc [DW_FORM_addr] (0x0000000000000000)
+; DUMP_INFO-NEXT: DW_AT_stmt_list [DW_FORM_data4] (0x00000000)
+; DUMP_INFO-NEXT: DW_AT_comp_dir [DW_FORM_GNU_strp_alt] (alt indirect string, offset: 0x6b)
+
+; DUMP_INFO: DW_TAG_imported_unit [4]
+; DUMP_INFO-NEXT: DW_AT_import [DW_FORM_GNU_ref_alt] (<alt 0xb>)
+
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