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ELF2: Make Writer::assignAddress() a bit shorter. NFC. 

llvm-svn: 249190
This commit is contained in:
Rui Ueyama 2015-10-02 21:23:17 +00:00
parent 6b2ed8bdca
commit 04dae558f4
1 changed files with 20 additions and 23 deletions
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43
lld/ELF/Writer.cpp
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@ -35,14 +35,12 @@ static const int VAStart = 0x10000;
namespace { namespace {
static uint32_t convertSectionFlagsToPHDRFlags(uint64_t Flags) { static uint32_t toPHDRFlags(uint64_t Flags) {
uint32_t Ret = PF_R; uint32_t Ret = PF_R;
if (Flags & SHF_WRITE) if (Flags & SHF_WRITE)
Ret |= PF_W; Ret |= PF_W;
if (Flags & SHF_EXECINSTR) if (Flags & SHF_EXECINSTR)
Ret |= PF_X; Ret |= PF_X;
return Ret; return Ret;
} }
@ -53,15 +51,18 @@ public:
typedef typedef
typename std::conditional<Is64Bits, Elf64_Phdr, Elf32_Phdr>::type HeaderT; typename std::conditional<Is64Bits, Elf64_Phdr, Elf32_Phdr>::type HeaderT;
ProgramHeader(uintX_t Type, uintX_t Flags) { ProgramHeader(uintX_t Type, uintX_t Flags, uintX_t FileOff, uintX_t VA) {
std::memset(&Header, 0, sizeof(HeaderT)); std::memset(&Header, 0, sizeof(HeaderT));
Header.p_type = Type; Header.p_type = Type;
Header.p_flags = Flags; Header.p_flags = Flags;
Header.p_align = PageSize; Header.p_align = PageSize;
Header.p_offset = FileOff;
Header.p_vaddr = VA;
Header.p_paddr = VA;
} }
void setValuesFromSection(OutputSectionBase<Is64Bits> &Sec) { void setValuesFromSection(OutputSectionBase<Is64Bits> &Sec) {
Header.p_flags = convertSectionFlagsToPHDRFlags(Sec.getFlags()); Header.p_flags = toPHDRFlags(Sec.getFlags());
Header.p_offset = Sec.getFileOff(); Header.p_offset = Sec.getFileOff();
Header.p_vaddr = Sec.getVA(); Header.p_vaddr = Sec.getVA();
Header.p_paddr = Header.p_vaddr; Header.p_paddr = Header.p_vaddr;
@ -131,9 +132,9 @@ private:
llvm::BumpPtrAllocator PAlloc; llvm::BumpPtrAllocator PAlloc;
std::vector<ProgramHeader<ELFT::Is64Bits> *> PHDRs; std::vector<ProgramHeader<ELFT::Is64Bits> *> PHDRs;
ProgramHeader<ELFT::Is64Bits> FileHeaderPHDR{PT_LOAD, PF_R}; ProgramHeader<ELFT::Is64Bits> FileHeaderPHDR{PT_LOAD, PF_R, 0, 0};
ProgramHeader<ELFT::Is64Bits> InterpPHDR{PT_INTERP, 0}; ProgramHeader<ELFT::Is64Bits> InterpPHDR{PT_INTERP, 0, 0, 0};
ProgramHeader<ELFT::Is64Bits> DynamicPHDR{PT_DYNAMIC, 0}; ProgramHeader<ELFT::Is64Bits> DynamicPHDR{PT_DYNAMIC, 0, 0, 0};
uintX_t FileSize; uintX_t FileSize;
uintX_t ProgramHeaderOff; uintX_t ProgramHeaderOff;
@ -450,7 +451,7 @@ template <class ELFT> void Writer<ELFT>::createSections() {
} }
template <class ELFT> template <class ELFT>
static bool outputSectionHasPHDR(OutputSectionBase<ELFT::Is64Bits> *Sec) { static bool needsPHDR(OutputSectionBase<ELFT::Is64Bits> *Sec) {
return Sec->getFlags() & SHF_ALLOC; return Sec->getFlags() & SHF_ALLOC;
} }
@ -472,7 +473,6 @@ template <class ELFT> void Writer<ELFT>::assignAddresses() {
if (needsInterpSection()) if (needsInterpSection())
PHDRs.push_back(&InterpPHDR); PHDRs.push_back(&InterpPHDR);
ProgramHeader<ELFT::Is64Bits> *LastPHDR = &FileHeaderPHDR;
// Create a PHDR for the file header. // Create a PHDR for the file header.
PHDRs.push_back(&FileHeaderPHDR); PHDRs.push_back(&FileHeaderPHDR);
FileHeaderPHDR.Header.p_vaddr = getVAStart(); FileHeaderPHDR.Header.p_vaddr = getVAStart();
@ -484,24 +484,21 @@ template <class ELFT> void Writer<ELFT>::assignAddresses() {
Sec->finalize(); Sec->finalize();
if (Sec->getSize()) { if (Sec->getSize()) {
uintX_t Flags = convertSectionFlagsToPHDRFlags(Sec->getFlags()); uintX_t Flags = toPHDRFlags(Sec->getFlags());
if (LastPHDR->Header.p_flags != Flags || ProgramHeader<ELFT::Is64Bits> *Last = PHDRs.back();
!outputSectionHasPHDR<ELFT>(Sec)) { if (Last->Header.p_flags != Flags || !needsPHDR<ELFT>(Sec)) {
// Flags changed. End current PHDR and potentially create a new one. // Flags changed. End current PHDR and potentially create a new one.
if (!LastPHDR->Closed) { if (!Last->Closed) {
LastPHDR->Header.p_filesz = FileOff - LastPHDR->Header.p_offset; Last->Header.p_filesz = FileOff - Last->Header.p_offset;
LastPHDR->Header.p_memsz = VA - LastPHDR->Header.p_vaddr; Last->Header.p_memsz = VA - Last->Header.p_vaddr;
LastPHDR->Closed = true; Last->Closed = true;
} }
if (outputSectionHasPHDR<ELFT>(Sec)) { if (needsPHDR<ELFT>(Sec)) {
LastPHDR = new (PAlloc) ProgramHeader<ELFT::Is64Bits>(PT_LOAD, Flags);
PHDRs.push_back(LastPHDR);
VA = RoundUpToAlignment(VA, PageSize); VA = RoundUpToAlignment(VA, PageSize);
FileOff = RoundUpToAlignment(FileOff, PageSize); FileOff = RoundUpToAlignment(FileOff, PageSize);
LastPHDR->Header.p_offset = FileOff; PHDRs.push_back(new (PAlloc) ProgramHeader<ELFT::Is64Bits>(
LastPHDR->Header.p_vaddr = VA; PT_LOAD, Flags, FileOff, VA));
LastPHDR->Header.p_paddr = VA;
} }
} }
} }