[lld] r286459 - Parse relocations only once.
Rafael Espindola via llvm-commits
llvm-commits at lists.llvm.org
Thu Nov 10 06:53:25 PST 2016
Author: rafael
Date: Thu Nov 10 08:53:24 2016
New Revision: 286459
URL: http://llvm.org/viewvc/llvm-project?rev=286459&view=rev
Log:
Parse relocations only once.
Relocations are the last thing that we wore storing a raw section
pointer to and parsing on demand.
With this patch we parse it only once and store a pointer to the
actual data.
The patch also changes where we store it. It is now in
InputSectionBase. Not all sections have relocations, but most do and
this simplifies the logic. It also means that we now only support one
relocation section per section. Given that that constraint is
maintained even with -r with gold bfd and lld, I think it is OK.
Modified:
lld/trunk/ELF/ICF.cpp
lld/trunk/ELF/InputFiles.cpp
lld/trunk/ELF/InputFiles.h
lld/trunk/ELF/InputSection.cpp
lld/trunk/ELF/InputSection.h
lld/trunk/ELF/MarkLive.cpp
lld/trunk/ELF/OutputSections.cpp
lld/trunk/ELF/Relocations.cpp
lld/trunk/ELF/Relocations.h
lld/trunk/ELF/Writer.cpp
lld/trunk/test/ELF/invalid/invalid-elf.test
Modified: lld/trunk/ELF/ICF.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/ICF.cpp?rev=286459&r1=286458&r2=286459&view=diff
==============================================================================
--- lld/trunk/ELF/ICF.cpp (original)
+++ lld/trunk/ELF/ICF.cpp Thu Nov 10 08:53:24 2016
@@ -120,10 +120,7 @@ private:
// relocation targets is not included in the hash value.
template <class ELFT> uint64_t ICF<ELFT>::getHash(InputSection<ELFT> *S) {
uint64_t Flags = S->Flags;
- uint64_t H = hash_combine(Flags, S->getSize());
- for (const Elf_Shdr *Rel : S->RelocSections)
- H = hash_combine(H, (uint64_t)Rel->sh_size);
- return H;
+ return hash_combine(Flags, S->getSize(), S->NumRelocations);
}
// Returns true if Sec is subject of ICF.
@@ -212,21 +209,15 @@ bool ICF<ELFT>::relocationEq(ArrayRef<Re
template <class ELFT>
bool ICF<ELFT>::equalsConstant(const InputSection<ELFT> *A,
const InputSection<ELFT> *B) {
- if (A->RelocSections.size() != B->RelocSections.size())
+ if (A->NumRelocations != B->NumRelocations)
return false;
- for (size_t I = 0, E = A->RelocSections.size(); I != E; ++I) {
- const Elf_Shdr *RA = A->RelocSections[I];
- const Elf_Shdr *RB = B->RelocSections[I];
- ELFFile<ELFT> FileA = A->getObj();
- ELFFile<ELFT> FileB = B->getObj();
- if (RA->sh_type == SHT_RELA) {
- if (!relocationEq(check(FileA.relas(RA)), check(FileB.relas(RB))))
- return false;
- } else {
- if (!relocationEq(check(FileA.rels(RA)), check(FileB.rels(RB))))
- return false;
- }
+ if (A->AreRelocsRela) {
+ if (!relocationEq(A->relas(), B->relas()))
+ return false;
+ } else {
+ if (!relocationEq(A->rels(), B->rels()))
+ return false;
}
return A->Flags == B->Flags && A->getSize() == B->getSize() &&
@@ -268,20 +259,9 @@ bool ICF<ELFT>::variableEq(const InputSe
template <class ELFT>
bool ICF<ELFT>::equalsVariable(const InputSection<ELFT> *A,
const InputSection<ELFT> *B) {
- for (size_t I = 0, E = A->RelocSections.size(); I != E; ++I) {
- const Elf_Shdr *RA = A->RelocSections[I];
- const Elf_Shdr *RB = B->RelocSections[I];
- ELFFile<ELFT> FileA = A->getObj();
- ELFFile<ELFT> FileB = B->getObj();
- if (RA->sh_type == SHT_RELA) {
- if (!variableEq(A, B, check(FileA.relas(RA)), check(FileB.relas(RB))))
- return false;
- } else {
- if (!variableEq(A, B, check(FileA.rels(RA)), check(FileB.rels(RB))))
- return false;
- }
- }
- return true;
+ if (A->AreRelocsRela)
+ return variableEq(A, B, A->relas(), B->relas());
+ return variableEq(A, B, A->rels(), B->rels());
}
// The main function of ICF.
Modified: lld/trunk/ELF/InputFiles.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/InputFiles.cpp?rev=286459&r1=286458&r2=286459&view=diff
==============================================================================
--- lld/trunk/ELF/InputFiles.cpp (original)
+++ lld/trunk/ELF/InputFiles.cpp Thu Nov 10 08:53:24 2016
@@ -353,19 +353,28 @@ elf::ObjectFile<ELFT>::createInputSectio
InputSectionBase<ELFT> *Target = getRelocTarget(Sec);
if (!Target)
return nullptr;
- if (auto *S = dyn_cast<InputSection<ELFT>>(Target)) {
- S->RelocSections.push_back(&Sec);
- return nullptr;
- }
- if (auto *S = dyn_cast<EhInputSection<ELFT>>(Target)) {
- if (S->RelocSection)
- fatal(getFilename(this) +
- ": multiple relocation sections to .eh_frame are not supported");
- S->RelocSection = &Sec;
- return nullptr;
+ if (Target->FirstRelocation)
+ fatal(getFilename(this) +
+ ": multiple relocation sections to one section are not supported");
+ if (!isa<InputSection<ELFT>>(Target) && !isa<EhInputSection<ELFT>>(Target))
+ fatal(getFilename(this) +
+ ": relocations pointing to SHF_MERGE are not supported");
+
+ size_t NumRelocations;
+ if (Sec.sh_type == SHT_RELA) {
+ ArrayRef<Elf_Rela> Rels = check(this->getObj().relas(&Sec));
+ Target->FirstRelocation = Rels.begin();
+ NumRelocations = Rels.size();
+ Target->AreRelocsRela = true;
+ } else {
+ ArrayRef<Elf_Rel> Rels = check(this->getObj().rels(&Sec));
+ Target->FirstRelocation = Rels.begin();
+ NumRelocations = Rels.size();
+ Target->AreRelocsRela = false;
}
- fatal(getFilename(this) +
- ": relocations pointing to SHF_MERGE are not supported");
+ assert(isUInt<31>(NumRelocations));
+ Target->NumRelocations = NumRelocations;
+ return nullptr;
}
}
Modified: lld/trunk/ELF/InputFiles.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/InputFiles.h?rev=286459&r1=286458&r2=286459&view=diff
==============================================================================
--- lld/trunk/ELF/InputFiles.h (original)
+++ lld/trunk/ELF/InputFiles.h Thu Nov 10 08:53:24 2016
@@ -121,6 +121,8 @@ protected:
// .o file.
template <class ELFT> class ObjectFile : public ELFFileBase<ELFT> {
typedef ELFFileBase<ELFT> Base;
+ typedef typename ELFT::Rel Elf_Rel;
+ typedef typename ELFT::Rela Elf_Rela;
typedef typename ELFT::Sym Elf_Sym;
typedef typename ELFT::Shdr Elf_Shdr;
typedef typename ELFT::SymRange Elf_Sym_Range;
Modified: lld/trunk/ELF/InputSection.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/InputSection.cpp?rev=286459&r1=286458&r2=286459&view=diff
==============================================================================
--- lld/trunk/ELF/InputSection.cpp (original)
+++ lld/trunk/ELF/InputSection.cpp Thu Nov 10 08:53:24 2016
@@ -56,6 +56,9 @@ InputSectionBase<ELFT>::InputSectionBase
!Config->GcSections || !(Flags & SHF_ALLOC)),
File(File), Flags(Flags), Entsize(Entsize), Type(Type), Link(Link),
Info(Info), Repl(this) {
+ NumRelocations = 0;
+ AreRelocsRela = false;
+
// The ELF spec states that a value of 0 means the section has
// no alignment constraits.
uint64_t V = std::max<uint64_t>(Addralign, 1);
@@ -466,12 +469,10 @@ void InputSectionBase<ELFT>::relocate(ui
// we handle relocations directly here.
auto *IS = dyn_cast<InputSection<ELFT>>(this);
if (IS && !(IS->Flags & SHF_ALLOC)) {
- for (const Elf_Shdr *RelSec : IS->RelocSections) {
- if (RelSec->sh_type == SHT_RELA)
- IS->relocateNonAlloc(Buf, check(IS->getObj().relas(RelSec)));
- else
- IS->relocateNonAlloc(Buf, check(IS->getObj().rels(RelSec)));
- }
+ if (IS->AreRelocsRela)
+ IS->relocateNonAlloc(Buf, IS->relas());
+ else
+ IS->relocateNonAlloc(Buf, IS->rels());
return;
}
@@ -609,12 +610,11 @@ template <class ELFT> void EhInputSectio
if (!this->Pieces.empty())
return;
- if (RelocSection) {
- ELFFile<ELFT> Obj = this->getObj();
- if (RelocSection->sh_type == SHT_RELA)
- split(check(Obj.relas(RelocSection)));
+ if (this->NumRelocations) {
+ if (this->AreRelocsRela)
+ split(this->relas());
else
- split(check(Obj.rels(RelocSection)));
+ split(this->rels());
return;
}
split(makeArrayRef<typename ELFT::Rela>(nullptr, nullptr));
Modified: lld/trunk/ELF/InputSection.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/InputSection.h?rev=286459&r1=286458&r2=286459&view=diff
==============================================================================
--- lld/trunk/ELF/InputSection.h (original)
+++ lld/trunk/ELF/InputSection.h Thu Nov 10 08:53:24 2016
@@ -96,7 +96,10 @@ public:
InputSectionBase()
: InputSectionData(Regular, "", ArrayRef<uint8_t>(), false, false),
- Repl(this) {}
+ Repl(this) {
+ NumRelocations = 0;
+ AreRelocsRela = false;
+ }
InputSectionBase(ObjectFile<ELFT> *File, const Elf_Shdr *Header,
StringRef Name, Kind SectionKind);
@@ -106,6 +109,20 @@ public:
Kind SectionKind);
OutputSectionBase *OutSec = nullptr;
+ // Relocations that refer to this section.
+ const Elf_Rel *FirstRelocation = nullptr;
+ unsigned NumRelocations : 31;
+ unsigned AreRelocsRela : 1;
+ ArrayRef<Elf_Rel> rels() const {
+ assert(!AreRelocsRela);
+ return llvm::makeArrayRef(FirstRelocation, NumRelocations);
+ }
+ ArrayRef<Elf_Rela> relas() const {
+ assert(AreRelocsRela);
+ return llvm::makeArrayRef(static_cast<const Elf_Rela *>(FirstRelocation),
+ NumRelocations);
+ }
+
// This pointer points to the "real" instance of this instance.
// Usually Repl == this. However, if ICF merges two sections,
// Repl pointer of one section points to another section. So,
@@ -219,8 +236,6 @@ public:
// rather than a single large blob of data.
std::vector<EhSectionPiece> Pieces;
- // Relocation section that refer to this one.
- const Elf_Shdr *RelocSection = nullptr;
};
// This corresponds to a non SHF_MERGE section of an input file.
@@ -247,9 +262,6 @@ public:
// beginning of the output section.
void writeTo(uint8_t *Buf);
- // Relocation sections that refer to this one.
- llvm::TinyPtrVector<const Elf_Shdr *> RelocSections;
-
// The offset from beginning of the output sections this section was assigned
// to. The writer sets a value.
uint64_t OutSecOff = 0;
Modified: lld/trunk/ELF/MarkLive.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/MarkLive.cpp?rev=286459&r1=286458&r2=286459&view=diff
==============================================================================
--- lld/trunk/ELF/MarkLive.cpp (original)
+++ lld/trunk/ELF/MarkLive.cpp Thu Nov 10 08:53:24 2016
@@ -80,15 +80,12 @@ static ResolvedReloc<ELFT> resolveReloc(
template <class ELFT>
static void forEachSuccessor(InputSection<ELFT> &Sec,
std::function<void(ResolvedReloc<ELFT>)> Fn) {
- ELFFile<ELFT> Obj = Sec.getFile()->getObj();
- for (const typename ELFT::Shdr *RelSec : Sec.RelocSections) {
- if (RelSec->sh_type == SHT_RELA) {
- for (const typename ELFT::Rela &Rel : check(Obj.relas(RelSec)))
- Fn(resolveReloc(Sec, Rel));
- } else {
- for (const typename ELFT::Rel &Rel : check(Obj.rels(RelSec)))
- Fn(resolveReloc(Sec, Rel));
- }
+ if (Sec.AreRelocsRela) {
+ for (const typename ELFT::Rela &Rel : Sec.relas())
+ Fn(resolveReloc(Sec, Rel));
+ } else {
+ for (const typename ELFT::Rel &Rel : Sec.rels())
+ Fn(resolveReloc(Sec, Rel));
}
if (Sec.DependentSection)
Fn({Sec.DependentSection, 0});
@@ -146,18 +143,17 @@ template <class ELFT>
static void
scanEhFrameSection(EhInputSection<ELFT> &EH,
std::function<void(ResolvedReloc<ELFT>)> Enqueue) {
- if (!EH.RelocSection)
+ if (!EH.NumRelocations)
return;
// Unfortunately we need to split .eh_frame early since some relocations in
// .eh_frame keep other section alive and some don't.
EH.split();
- ELFFile<ELFT> EObj = EH.getFile()->getObj();
- if (EH.RelocSection->sh_type == SHT_RELA)
- scanEhFrameSection(EH, check(EObj.relas(EH.RelocSection)), Enqueue);
+ if (EH.AreRelocsRela)
+ scanEhFrameSection(EH, EH.relas(), Enqueue);
else
- scanEhFrameSection(EH, check(EObj.rels(EH.RelocSection)), Enqueue);
+ scanEhFrameSection(EH, EH.rels(), Enqueue);
}
// We do not garbage-collect two types of sections:
Modified: lld/trunk/ELF/OutputSections.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/OutputSections.cpp?rev=286459&r1=286458&r2=286459&view=diff
==============================================================================
--- lld/trunk/ELF/OutputSections.cpp (original)
+++ lld/trunk/ELF/OutputSections.cpp Thu Nov 10 08:53:24 2016
@@ -1162,12 +1162,11 @@ void EhOutputSection<ELFT>::addSection(I
if (Sec->Pieces.empty())
return;
- if (const Elf_Shdr *RelSec = Sec->RelocSection) {
- ELFFile<ELFT> Obj = Sec->getFile()->getObj();
- if (RelSec->sh_type == SHT_RELA)
- addSectionAux(Sec, check(Obj.relas(RelSec)));
+ if (Sec->NumRelocations) {
+ if (Sec->AreRelocsRela)
+ addSectionAux(Sec, Sec->relas());
else
- addSectionAux(Sec, check(Obj.rels(RelSec)));
+ addSectionAux(Sec, Sec->rels());
return;
}
addSectionAux(Sec, makeArrayRef<Elf_Rela>(nullptr, nullptr));
Modified: lld/trunk/ELF/Relocations.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Relocations.cpp?rev=286459&r1=286458&r2=286459&view=diff
==============================================================================
--- lld/trunk/ELF/Relocations.cpp (original)
+++ lld/trunk/ELF/Relocations.cpp Thu Nov 10 08:53:24 2016
@@ -787,14 +787,11 @@ static void scanRelocs(InputSectionBase<
}
}
-template <class ELFT>
-void scanRelocations(InputSectionBase<ELFT> &S,
- const typename ELFT::Shdr &RelSec) {
- ELFFile<ELFT> EObj = S.getFile()->getObj();
- if (RelSec.sh_type == SHT_RELA)
- scanRelocs(S, check(EObj.relas(&RelSec)));
+template <class ELFT> void scanRelocations(InputSectionBase<ELFT> &S) {
+ if (S.AreRelocsRela)
+ scanRelocs(S, S.relas());
else
- scanRelocs(S, check(EObj.rels(&RelSec)));
+ scanRelocs(S, S.rels());
}
template <class ELFT, class RelTy>
@@ -817,33 +814,22 @@ static void createThunks(InputSectionBas
}
}
-template <class ELFT>
-void createThunks(InputSectionBase<ELFT> &S,
- const typename ELFT::Shdr &RelSec) {
- ELFFile<ELFT> EObj = S.getFile()->getObj();
- if (RelSec.sh_type == SHT_RELA)
- createThunks(S, check(EObj.relas(&RelSec)));
+template <class ELFT> void createThunks(InputSectionBase<ELFT> &S) {
+ if (S.AreRelocsRela)
+ createThunks(S, S.relas());
else
- createThunks(S, check(EObj.rels(&RelSec)));
+ createThunks(S, S.rels());
}
-template void scanRelocations<ELF32LE>(InputSectionBase<ELF32LE> &,
- const ELF32LE::Shdr &);
-template void scanRelocations<ELF32BE>(InputSectionBase<ELF32BE> &,
- const ELF32BE::Shdr &);
-template void scanRelocations<ELF64LE>(InputSectionBase<ELF64LE> &,
- const ELF64LE::Shdr &);
-template void scanRelocations<ELF64BE>(InputSectionBase<ELF64BE> &,
- const ELF64BE::Shdr &);
-
-template void createThunks<ELF32LE>(InputSectionBase<ELF32LE> &,
- const ELF32LE::Shdr &);
-template void createThunks<ELF32BE>(InputSectionBase<ELF32BE> &,
- const ELF32BE::Shdr &);
-template void createThunks<ELF64LE>(InputSectionBase<ELF64LE> &,
- const ELF64LE::Shdr &);
-template void createThunks<ELF64BE>(InputSectionBase<ELF64BE> &,
- const ELF64BE::Shdr &);
+template void scanRelocations<ELF32LE>(InputSectionBase<ELF32LE> &);
+template void scanRelocations<ELF32BE>(InputSectionBase<ELF32BE> &);
+template void scanRelocations<ELF64LE>(InputSectionBase<ELF64LE> &);
+template void scanRelocations<ELF64BE>(InputSectionBase<ELF64BE> &);
+
+template void createThunks<ELF32LE>(InputSectionBase<ELF32LE> &);
+template void createThunks<ELF32BE>(InputSectionBase<ELF32BE> &);
+template void createThunks<ELF64LE>(InputSectionBase<ELF64LE> &);
+template void createThunks<ELF64BE>(InputSectionBase<ELF64BE> &);
template std::string getLocation<ELF32LE>(InputSectionBase<ELF32LE> &S,
uint32_t Offset);
Modified: lld/trunk/ELF/Relocations.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Relocations.h?rev=286459&r1=286458&r2=286459&view=diff
==============================================================================
--- lld/trunk/ELF/Relocations.h (original)
+++ lld/trunk/ELF/Relocations.h Thu Nov 10 08:53:24 2016
@@ -81,11 +81,9 @@ struct Relocation {
SymbolBody *Sym;
};
-template <class ELFT>
-void scanRelocations(InputSectionBase<ELFT> &, const typename ELFT::Shdr &);
+template <class ELFT> void scanRelocations(InputSectionBase<ELFT> &);
-template <class ELFT>
-void createThunks(InputSectionBase<ELFT> &, const typename ELFT::Shdr &);
+template <class ELFT> void createThunks(InputSectionBase<ELFT> &);
template <class ELFT>
std::string getLocation(InputSectionBase<ELFT> &S, typename ELFT::uint Offset);
Modified: lld/trunk/ELF/Writer.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Writer.cpp?rev=286459&r1=286458&r2=286459&view=diff
==============================================================================
--- lld/trunk/ELF/Writer.cpp (original)
+++ lld/trunk/ELF/Writer.cpp Thu Nov 10 08:53:24 2016
@@ -54,8 +54,7 @@ private:
void addReservedSymbols();
void addInputSec(InputSectionBase<ELFT> *S);
void createSections();
- void forEachRelSec(std::function<void(InputSectionBase<ELFT> &,
- const typename ELFT::Shdr &)> Fn);
+ void forEachRelSec(std::function<void(InputSectionBase<ELFT> &)> Fn);
void sortSections();
void finalizeSections();
void addPredefinedSections();
@@ -694,8 +693,7 @@ static void sortBySymbolsOrder(ArrayRef<
template <class ELFT>
void Writer<ELFT>::forEachRelSec(
- std::function<void(InputSectionBase<ELFT> &, const typename ELFT::Shdr &)>
- Fn) {
+ std::function<void(InputSectionBase<ELFT> &)> Fn) {
for (InputSectionBase<ELFT> *IS : Symtab<ELFT>::X->Sections) {
if (!IS->Live)
continue;
@@ -706,14 +704,8 @@ void Writer<ELFT>::forEachRelSec(
// processed by InputSection::relocateNonAlloc.
if (!(IS->Flags & SHF_ALLOC))
continue;
- if (auto *S = dyn_cast<InputSection<ELFT>>(IS)) {
- for (const Elf_Shdr *RelSec : S->RelocSections)
- Fn(*S, *RelSec);
- continue;
- }
- if (auto *S = dyn_cast<EhInputSection<ELFT>>(IS))
- if (S->RelocSection)
- Fn(*S, *S->RelocSection);
+ if (isa<InputSection<ELFT>>(IS) || isa<EhInputSection<ELFT>>(IS))
+ Fn(*IS);
}
}
Modified: lld/trunk/test/ELF/invalid/invalid-elf.test
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/invalid/invalid-elf.test?rev=286459&r1=286458&r2=286459&view=diff
==============================================================================
--- lld/trunk/test/ELF/invalid/invalid-elf.test (original)
+++ lld/trunk/test/ELF/invalid/invalid-elf.test Thu Nov 10 08:53:24 2016
@@ -26,6 +26,6 @@
# RUN: not ld.lld %p/Inputs/multiple-eh-relocs.elf -o %t2 2>&1 | \
# RUN: FileCheck --check-prefix=INVALID-EH-RELOCS %s
-# INVALID-EH-RELOCS: multiple relocation sections to .eh_frame are not supported
+# INVALID-EH-RELOCS: multiple relocation sections to one section are not supported
.long foo
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