DebugInfo: Move type units into the debug_types section with appropriate comdat grouping and type unit headers

This commit does not complete the type units feature - there are issues
around fission support (skeletal type units, pubtypes/pubnames) and
hashing of some types including those containing references to types in
other type units.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197073 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
David Blaikie 2013-12-11 21:36:27 +00:00
parent bd71b0a161
commit 3d2670cc54
8 changed files with 93 additions and 29 deletions

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@ -262,6 +262,8 @@ public:
const MCSection *getDwarfInfoDWOSection() const {
return DwarfInfoDWOSection;
}
const MCSection *getDwarfTypesSection(uint64_t Hash) const;
const MCSection *getDwarfTypesDWOSection(uint64_t Hash) const;
const MCSection *getDwarfAbbrevDWOSection() const {
return DwarfAbbrevDWOSection;
}

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@ -16,6 +16,7 @@
#include "llvm/ADT/StringRef.h"
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ELF.h"
#include "llvm/Support/raw_ostream.h"
@ -60,8 +61,13 @@ public:
StringRef getSectionName() const { return SectionName; }
virtual std::string getLabelBeginName() const {
return SectionName.str() + "_begin"; }
if (Group)
return (SectionName.str() + '_' + Group->getName() + "_begin").str();
return SectionName.str() + "_begin";
}
virtual std::string getLabelEndName() const {
if (Group)
return (SectionName.str() + '_' + Group->getName() + "_end").str();
return SectionName.str() + "_end";
}
unsigned getType() const { return Type; }

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@ -3056,19 +3056,17 @@ void DwarfDebug::addDwarfTypeUnitType(uint16_t Language, DIE *RefDie,
// referenced type, or possibly walk the precomputed hashes of related types
// at the end.
uint64_t Signature = DIEHash().computeTypeSignature(*Die);
NewTU->setTypeSignature(Signature);
NewTU->setType(Die);
// Remove the References vector and add the type hash.
I->second.first = Signature;
I->second.second = NULL;
NewTU->initSection(
useSplitDwarf() ? Asm->getObjFileLowering().getDwarfInfoDWOSection()
: Asm->getObjFileLowering().getDwarfInfoSection(),
// FIXME: This is subtle (using the info section even when
// this CU is in the dwo section) and necessary for the
// current arange code - ideally it should iterate
// skeleton units, not full units, if it's going to reference skeletons
useSplitDwarf() ? NULL : DwarfInfoSectionSym);
useSplitDwarf()
? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
: Asm->getObjFileLowering().getDwarfTypesSection(Signature));
}
// Populate all the signatures.

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@ -1997,3 +1997,27 @@ void DwarfUnit::emitHeader(const MCSection *ASection,
Asm->OutStreamer.AddComment("Address Size (in bytes)");
Asm->EmitInt8(Asm->getDataLayout().getPointerSize());
}
void DwarfTypeUnit::emitHeader(const MCSection *ASection,
const MCSymbol *ASectionSym) const {
DwarfUnit::emitHeader(ASection, ASectionSym);
Asm->OutStreamer.AddComment("Type Signature");
Asm->OutStreamer.EmitIntValue(TypeSignature, sizeof(TypeSignature));
Asm->OutStreamer.AddComment("Type DIE Offset");
Asm->OutStreamer.EmitIntValue(Ty->getOffset(), sizeof(Ty->getOffset()));
}
void DwarfTypeUnit::initSection(const MCSection *Section) {
assert(!this->Section);
this->Section = Section;
// Since each type unit is contained in its own COMDAT section, the begin
// label and the section label are the same. Using the begin label emission in
// DwarfDebug to emit the section label as well is slightly subtle/sneaky, but
// the only other alternative of lazily constructing start-of-section labels
// and storing a mapping in DwarfDebug (or AsmPrinter).
this->SectionSym = this->LabelBegin =
Asm->GetTempSymbol(Section->getLabelBeginName(), getUniqueID());
this->LabelEnd =
Asm->GetTempSymbol(Section->getLabelEndName(), getUniqueID());
this->LabelRange = Asm->GetTempSymbol("gnu_ranges", getUniqueID());
}

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@ -413,14 +413,15 @@ public:
/// Compute the size of a header for this unit, not including the initial
/// length field.
unsigned getHeaderSize() const {
virtual unsigned getHeaderSize() const {
return sizeof(int16_t) + // DWARF version number
sizeof(int32_t) + // Offset Into Abbrev. Section
sizeof(int8_t); // Pointer Size (in bytes)
}
/// Emit the header for this unit, not including the initial length field.
void emitHeader(const MCSection *ASection, const MCSymbol *ASectionSym) const;
virtual void emitHeader(const MCSection *ASection,
const MCSymbol *ASectionSym) const;
protected:
/// getOrCreateStaticMemberDIE - Create new static data member DIE.
@ -513,12 +514,25 @@ public:
class DwarfTypeUnit : public DwarfUnit {
private:
uint16_t Language;
uint64_t TypeSignature;
const DIE *Ty;
public:
DwarfTypeUnit(unsigned UID, DIE *D, uint16_t Language, AsmPrinter *A,
DwarfDebug *DW, DwarfFile *DWU);
void setTypeSignature(uint64_t Signature) { TypeSignature = Signature; }
void setType(const DIE *Ty) { this->Ty = Ty; }
uint16_t getLanguage() const LLVM_OVERRIDE { return Language; }
/// Emit the header for this unit, not including the initial length field.
void emitHeader(const MCSection *ASection, const MCSymbol *ASectionSym) const
LLVM_OVERRIDE;
unsigned getHeaderSize() const LLVM_OVERRIDE {
return DwarfUnit::getHeaderSize() + sizeof(uint64_t) + // Type Signature
sizeof(uint32_t); // Type DIE Offset
}
void initSection(const MCSection *Section);
};
} // end llvm namespace
#endif

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@ -9,6 +9,7 @@
#include "llvm/MC/MCObjectFileInfo.h"
#include "llvm/ADT/Triple.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCSectionCOFF.h"
@ -718,6 +719,17 @@ void MCObjectFileInfo::InitMCObjectFileInfo(StringRef TT, Reloc::Model relocm,
}
}
const MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const {
return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP,
SectionKind::getMetadata(), 0, utostr(Hash));
}
const MCSection *
MCObjectFileInfo::getDwarfTypesDWOSection(uint64_t Hash) const {
return Ctx->getELFSection(".debug_types.dwo", ELF::SHT_GROUP, 0,
SectionKind::getMetadata(), 0, utostr(Hash));
}
void MCObjectFileInfo::InitEHFrameSection() {
if (Env == IsMachO)
EHFrameSection =

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@ -1,6 +1,6 @@
; REQUIRES: object-emission
; RUN: llc -o - %s -filetype=obj -O0 -generate-type-units -mtriple=x86_64-unknown-linux-gnu | llvm-dwarfdump -debug-dump=info - | FileCheck %s
; RUN: llc -o - %s -filetype=obj -O0 -generate-dwarf-pub-sections=Disable -generate-type-units -mtriple=x86_64-unknown-linux-gnu | llvm-dwarfdump -debug-dump=types - | FileCheck %s
; struct foo {
; } f;

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@ -45,13 +45,12 @@
; CHECK-LABEL: .debug_info contents:
; CHECK: Compile Unit: length = [[CU_SIZE:[0-9a-f]+]]
; Check that we generate a hash for bar and the value.
; CHECK-LABEL: DW_AT_GNU_odr_signature [DW_FORM_data8] (0x200520c0d5b90eff)
; CHECK: DW_TAG_structure_type
; CHECK-NEXT: debug_str{{.*}}"bar"
; CHECK-LABEL: .debug_types contents:
; Check that we generate a hash for fluffy and the value.
; CHECK-LABEL: DW_AT_GNU_odr_signature [DW_FORM_data8] (0x9a0124d5a0c21c52)
; CHECK-LABEL: type_signature = 0x139b2e1ea94afec7
; CHECK: DW_AT_GNU_odr_signature [DW_FORM_data8] (0x9a0124d5a0c21c52)
; CHECK: DW_TAG_namespace
; CHECK-NEXT: debug_str{{.*}}"echidna"
; CHECK: DW_TAG_namespace
@ -61,10 +60,24 @@
; CHECK: DW_TAG_class_type
; CHECK-NEXT: debug_str{{.*}}"fluffy"
; We emit no hash for walrus since the type is contained in an anonymous
; Check that we generate a hash for wombat and the value, but not for the
; anonymous type contained within.
; CHECK-LABEL: type_signature = 0x73776f130648b986
; CHECK: DW_AT_GNU_odr_signature [DW_FORM_data8] (0x685bcc220141e9d7)
; CHECK: DW_TAG_structure_type
; CHECK-NEXT: debug_str{{.*}}"wombat"
; Check that we generate a hash for bar and the value.
; CHECK-LABEL: type_signature = 0x6a7ee3d400662e88
; CHECK: DW_AT_GNU_odr_signature [DW_FORM_data8] (0x200520c0d5b90eff)
; CHECK: DW_TAG_structure_type
; CHECK-NEXT: debug_str{{.*}}"bar"
; namespace and won't violate any ODR-ness.
; CHECK-LABEL: type_signature = 0xc0d031d6449dbca7
; CHECK: DW_TAG_type_unit
; CHECK-NOT: NULL
; We emit no hash for walrus since the type is contained in an anonymous
; CHECK-NOT: DW_AT_GNU_odr_signature
; CHECK: DW_TAG_structure_type
; CHECK-NEXT: debug_str{{.*}}"walrus"
@ -74,13 +87,8 @@
; CHECK: DW_TAG_subprogram
; Check that we generate a hash for wombat and the value, but not for the
; anonymous type contained within.
; CHECK-LABEL: DW_AT_GNU_odr_signature [DW_FORM_data8] (0x685bcc220141e9d7)
; CHECK: DW_TAG_structure_type
; CHECK-NEXT: debug_str{{.*}}"wombat"
; CHECK: DW_TAG_type_unit
; CHECK: DW_TAG_structure_type
; Check that we generate no ODR hash for the anonymous type nested inside 'wombat'
; CHECK-LABEL: type_signature = 0xbf6fc40e82583d7c
; The signature for the outer 'wombat' type - this can be FileChecked once the
; type units are moved to their own section with the full type unit header
; including the signature
@ -98,20 +106,20 @@
; CHECK-NEXT: unit_size = [[CU_SIZE]]
; CHECK-NEXT: Offset Name
; Type unit for 'bar'
; CHECK-NEXT: unit_size = 0x0000001f
; CHECK-NEXT: unit_size = 0x0000002b
; CHECK-NEXT: Offset Name
; CHECK-NEXT: "bar"
; CHECK-NEXT: unit_size = 0x00000059
; CHECK-NEXT: unit_size = 0x00000065
; CHECK-NEXT: Offset Name
; CHECK-NEXT: "int"
; CHECK-NEXT: "echidna::capybara::mongoose::fluffy"
; CHECK-NEXT: unit_size = 0x0000002f
; CHECK-NEXT: unit_size = 0x0000003b
; CHECK-NEXT: Offset Name
; CHECK-NEXT: "walrus"
; CHECK-NEXT: unit_size = 0x00000036
; CHECK-NEXT: unit_size = 0x00000042
; CHECK-NEXT: Offset Name
; CHECK-NEXT: "wombat"
; CHECK-NEXT: unit_size = 0x0000003f
; CHECK-NEXT: unit_size = 0x0000004b
; CHECK-NEXT: Offset Name
; CHECK-NEXT: "int"