//===- HexagonRelocator.cpp -----------------------------------------------===//
//
// The MCLinker Project
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "HexagonRelocator.h"
#include "HexagonRelocationFunctions.h"
#include "HexagonEncodings.h"
#include "mcld/LD/ELFFileFormat.h"
#include "mcld/LD/LDSymbol.h"
#include "mcld/Support/MsgHandling.h"
#include <llvm/ADT/Twine.h>
#include <llvm/Support/DataTypes.h>
#include <llvm/Support/ELF.h>
namespace mcld {
//===--------------------------------------------------------------------===//
// Relocation Helper Functions
//===--------------------------------------------------------------------===//
/// helper_DynRel - Get an relocation entry in .rela.dyn
static Relocation& helper_DynRel_init(ResolveInfo* pSym,
Fragment& pFrag,
uint64_t pOffset,
Relocator::Type pType,
HexagonRelocator& pParent) {
HexagonLDBackend& ld_backend = pParent.getTarget();
Relocation& rela_entry = *ld_backend.getRelaDyn().create();
rela_entry.setType(pType);
rela_entry.targetRef().assign(pFrag, pOffset);
if (pType == llvm::ELF::R_HEX_RELATIVE || pSym == NULL)
rela_entry.setSymInfo(0);
else
rela_entry.setSymInfo(pSym);
return rela_entry;
}
/// helper_use_relative_reloc - Check if symbol can use relocation
/// R_HEX_RELATIVE
static bool helper_use_relative_reloc(const ResolveInfo& pSym,
const HexagonRelocator& pFactory) {
// if symbol is dynamic or undefine or preemptible
if (pSym.isDyn() || pSym.isUndef() ||
pFactory.getTarget().isSymbolPreemptible(pSym))
return false;
return true;
}
static HexagonGOTEntry& helper_GOT_init(Relocation& pReloc,
bool pHasRel,
HexagonRelocator& pParent) {
// rsym - The relocation target symbol
ResolveInfo* rsym = pReloc.symInfo();
HexagonLDBackend& ld_backend = pParent.getTarget();
assert(pParent.getSymGOTMap().lookUp(*rsym) == NULL);
HexagonGOTEntry* got_entry = ld_backend.getGOT().create();
pParent.getSymGOTMap().record(*rsym, *got_entry);
if (!pHasRel) {
// No corresponding dynamic relocation, initialize to the symbol value.
got_entry->setValue(HexagonRelocator::SymVal);
} else {
// Initialize got_entry content and the corresponding dynamic relocation.
if (helper_use_relative_reloc(*rsym, pParent)) {
helper_DynRel_init(
rsym, *got_entry, 0x0, llvm::ELF::R_HEX_RELATIVE, pParent);
got_entry->setValue(HexagonRelocator::SymVal);
} else {
helper_DynRel_init(
rsym, *got_entry, 0x0, llvm::ELF::R_HEX_GLOB_DAT, pParent);
got_entry->setValue(0);
}
}
return *got_entry;
}
static Relocator::Address helper_get_GOT_address(ResolveInfo& pSym,
HexagonRelocator& pParent) {
HexagonGOTEntry* got_entry = pParent.getSymGOTMap().lookUp(pSym);
assert(got_entry != NULL);
return pParent.getTarget().getGOT().addr() + got_entry->getOffset();
}
static PLTEntryBase& helper_PLT_init(Relocation& pReloc,
HexagonRelocator& pParent) {
// rsym - The relocation target symbol
ResolveInfo* rsym = pReloc.symInfo();
HexagonLDBackend& ld_backend = pParent.getTarget();
assert(pParent.getSymPLTMap().lookUp(*rsym) == NULL);
PLTEntryBase* plt_entry = ld_backend.getPLT().create();
pParent.getSymPLTMap().record(*rsym, *plt_entry);
assert(pParent.getSymGOTPLTMap().lookUp(*rsym) == NULL &&
"PLT entry not exist, but DynRel entry exist!");
HexagonGOTEntry* gotplt_entry = ld_backend.getGOTPLT().create();
pParent.getSymGOTPLTMap().record(*rsym, *gotplt_entry);
// init the corresponding rel entry in .rela.plt
Relocation& rela_entry = *ld_backend.getRelaPLT().create();
rela_entry.setType(llvm::ELF::R_HEX_JMP_SLOT);
rela_entry.targetRef().assign(*gotplt_entry);
rela_entry.setSymInfo(rsym);
return *plt_entry;
}
static Relocator::Address helper_get_PLT_address(ResolveInfo& pSym,
HexagonRelocator& pParent) {
PLTEntryBase* plt_entry = pParent.getSymPLTMap().lookUp(pSym);
assert(plt_entry != NULL);
return pParent.getTarget().getPLT().addr() + plt_entry->getOffset();
}
//===--------------------------------------------------------------------===//
// Relocation Functions and Tables
//===--------------------------------------------------------------------===//
DECL_HEXAGON_APPLY_RELOC_FUNCS
/// the prototype of applying function
typedef Relocator::Result (*ApplyFunctionType)(Relocation& pReloc,
HexagonRelocator& pParent);
// the table entry of applying functions
struct ApplyFunctionTriple {
ApplyFunctionType func;
unsigned int type;
const char* name;
};
// declare the table of applying functions
static const ApplyFunctionTriple ApplyFunctions[] = {
DECL_HEXAGON_APPLY_RELOC_FUNC_PTRS};
static uint32_t findBitMask(uint32_t insn,
Instruction* encodings,
int32_t numInsns) {
for (int32_t i = 0; i < numInsns; ++i) {
if (((insn & 0xc000) == 0) && !(encodings[i].isDuplex))
continue;
if (((insn & 0xc000) != 0) && (encodings[i].isDuplex))
continue;
if (((encodings[i].insnMask) & insn) == encodings[i].insnCmpMask)
return encodings[i].insnBitMask;
}
assert(0);
// Should not be here, but add a return for -Werror=return-type
// error: control reaches end of non-void function
return -1;
}
#define FINDBITMASK(INSN) \
findBitMask((uint32_t)INSN, \
insn_encodings, \
sizeof(insn_encodings) / sizeof(Instruction))
//===--------------------------------------------------------------------===//
// HexagonRelocator
//===--------------------------------------------------------------------===//
HexagonRelocator::HexagonRelocator(HexagonLDBackend& pParent,
const LinkerConfig& pConfig)
: Relocator(pConfig), m_Target(pParent) {
}
HexagonRelocator::~HexagonRelocator() {
}
Relocator::Result HexagonRelocator::applyRelocation(Relocation& pRelocation) {
Relocation::Type type = pRelocation.type();
if (type > 85) { // 86-255 relocs do not exists for Hexagon
return Relocator::Unknown;
}
// apply the relocation
return ApplyFunctions[type].func(pRelocation, *this);
}
const char* HexagonRelocator::getName(Relocation::Type pType) const {
return ApplyFunctions[pType].name;
}
Relocator::Size HexagonRelocator::getSize(Relocation::Type pType) const {
return 32;
}
void HexagonRelocator::scanRelocation(Relocation& pReloc,
IRBuilder& pLinker,
Module& pModule,
LDSection& pSection,
Input& pInput) {
if (LinkerConfig::Object == config().codeGenType())
return;
// rsym - The relocation target symbol
ResolveInfo* rsym = pReloc.symInfo();
assert(rsym != NULL &&
"ResolveInfo of relocation not set while scanRelocation");
if (config().isCodeStatic())
return;
assert(pSection.getLink() != NULL);
if ((pSection.getLink()->flag() & llvm::ELF::SHF_ALLOC) == 0)
return;
if (rsym->isLocal()) // rsym is local
scanLocalReloc(pReloc, pLinker, pModule, pSection);
else // rsym is external
scanGlobalReloc(pReloc, pLinker, pModule, pSection);
// check if we should issue undefined reference for the relocation target
// symbol
if (rsym->isUndef() && !rsym->isDyn() && !rsym->isWeak() && !rsym->isNull())
issueUndefRef(pReloc, pSection, pInput);
}
void HexagonRelocator::addCopyReloc(ResolveInfo& pSym,
HexagonLDBackend& pTarget) {
Relocation& rel_entry = *pTarget.getRelaDyn().create();
rel_entry.setType(pTarget.getCopyRelType());
assert(pSym.outSymbol()->hasFragRef());
rel_entry.targetRef().assign(*pSym.outSymbol()->fragRef());
rel_entry.setSymInfo(&pSym);
}
void HexagonRelocator::scanLocalReloc(Relocation& pReloc,
IRBuilder& pBuilder,
Module& pModule,
LDSection& pSection) {
// rsym - The relocation target symbol
ResolveInfo* rsym = pReloc.symInfo();
switch (pReloc.type()) {
case llvm::ELF::R_HEX_LO16:
case llvm::ELF::R_HEX_HI16:
case llvm::ELF::R_HEX_16:
case llvm::ELF::R_HEX_8:
case llvm::ELF::R_HEX_32_6_X:
case llvm::ELF::R_HEX_16_X:
case llvm::ELF::R_HEX_12_X:
case llvm::ELF::R_HEX_11_X:
case llvm::ELF::R_HEX_10_X:
case llvm::ELF::R_HEX_9_X:
case llvm::ELF::R_HEX_8_X:
case llvm::ELF::R_HEX_7_X:
case llvm::ELF::R_HEX_6_X:
assert(!(rsym->reserved() & ReserveRel) &&
"Cannot apply this relocation for read only section");
return;
case llvm::ELF::R_HEX_32:
// If buiding PIC object (shared library or PIC executable),
// a dynamic relocations with RELATIVE type to this location is needed.
// Reserve an entry in .rel.dyn
if (config().isCodeIndep()) {
Relocation& reloc = helper_DynRel_init(rsym,
*pReloc.targetRef().frag(),
pReloc.targetRef().offset(),
llvm::ELF::R_HEX_RELATIVE,
*this);
// we need to set up the relocation addend at apply relocation, record
// the
// relocation
getRelRelMap().record(pReloc, reloc);
// set Rel bit
rsym->setReserved(rsym->reserved() | ReserveRel);
getTarget().checkAndSetHasTextRel(*pSection.getLink());
}
return;
default:
return;
}
}
void HexagonRelocator::scanGlobalReloc(Relocation& pReloc,
IRBuilder& pBuilder,
Module& pModule,
LDSection& pSection) {
// rsym - The relocation target symbol
ResolveInfo* rsym = pReloc.symInfo();
HexagonLDBackend& ld_backend = getTarget();
switch (pReloc.type()) {
case llvm::ELF::R_HEX_LO16:
case llvm::ELF::R_HEX_HI16:
case llvm::ELF::R_HEX_16:
case llvm::ELF::R_HEX_8:
case llvm::ELF::R_HEX_32_6_X:
case llvm::ELF::R_HEX_16_X:
case llvm::ELF::R_HEX_12_X:
case llvm::ELF::R_HEX_11_X:
case llvm::ELF::R_HEX_10_X:
case llvm::ELF::R_HEX_9_X:
case llvm::ELF::R_HEX_8_X:
case llvm::ELF::R_HEX_7_X:
case llvm::ELF::R_HEX_6_X:
assert(!(rsym->reserved() & ReserveRel) &&
"Cannot apply this relocation for read only section");
return;
case llvm::ELF::R_HEX_32:
if (ld_backend.symbolNeedsPLT(*rsym)) {
// create PLT for this symbol if it does not have.
if (!(rsym->reserved() & ReservePLT)) {
helper_PLT_init(pReloc, *this);
rsym->setReserved(rsym->reserved() | ReservePLT);
}
}
if (ld_backend.symbolNeedsDynRel(
*rsym, (rsym->reserved() & ReservePLT), true)) {
if (ld_backend.symbolNeedsCopyReloc(pReloc, *rsym)) {
LDSymbol& cpy_sym =
defineSymbolforCopyReloc(pBuilder, *rsym, ld_backend);
addCopyReloc(*cpy_sym.resolveInfo(), ld_backend);
} else {
Relocation& reloc = helper_DynRel_init(rsym,
*pReloc.targetRef().frag(),
pReloc.targetRef().offset(),
llvm::ELF::R_HEX_RELATIVE,
*this);
// we need to set up the relocation addend at apply relocation, record
// the
// relocation
getRelRelMap().record(pReloc, reloc);
rsym->setReserved(rsym->reserved() | ReserveRel);
ld_backend.checkAndSetHasTextRel(*pSection.getLink());
}
}
return;
case llvm::ELF::R_HEX_GOTREL_LO16:
case llvm::ELF::R_HEX_GOTREL_HI16:
case llvm::ELF::R_HEX_GOTREL_32:
case llvm::ELF::R_HEX_GOTREL_32_6_X:
case llvm::ELF::R_HEX_GOTREL_16_X:
case llvm::ELF::R_HEX_GOTREL_11_X:
// This assumes that GOT exists
return;
case llvm::ELF::R_HEX_GOT_LO16:
case llvm::ELF::R_HEX_GOT_HI16:
case llvm::ELF::R_HEX_GOT_32:
case llvm::ELF::R_HEX_GOT_16:
case llvm::ELF::R_HEX_GOT_32_6_X:
case llvm::ELF::R_HEX_GOT_16_X:
case llvm::ELF::R_HEX_GOT_11_X:
// Symbol needs GOT entry, reserve entry in .got
// return if we already create GOT for this symbol
if (rsym->reserved() & ReserveGOT)
return;
// If the GOT is used in statically linked binaries,
// the GOT entry is enough and no relocation is needed.
if (config().isCodeStatic())
helper_GOT_init(pReloc, false, *this);
else
helper_GOT_init(pReloc, true, *this);
// set GOT bit
rsym->setReserved(rsym->reserved() | ReserveGOT);
return;
case llvm::ELF::R_HEX_B22_PCREL:
case llvm::ELF::R_HEX_B15_PCREL:
case llvm::ELF::R_HEX_B7_PCREL:
case llvm::ELF::R_HEX_B13_PCREL:
case llvm::ELF::R_HEX_B9_PCREL:
case llvm::ELF::R_HEX_B32_PCREL_X:
case llvm::ELF::R_HEX_B22_PCREL_X:
case llvm::ELF::R_HEX_B15_PCREL_X:
case llvm::ELF::R_HEX_B13_PCREL_X:
case llvm::ELF::R_HEX_B9_PCREL_X:
case llvm::ELF::R_HEX_B7_PCREL_X:
case llvm::ELF::R_HEX_32_PCREL:
case llvm::ELF::R_HEX_6_PCREL_X:
case llvm::ELF::R_HEX_PLT_B22_PCREL:
if (rsym->reserved() & ReservePLT)
return;
if (ld_backend.symbolNeedsPLT(*rsym) ||
pReloc.type() == llvm::ELF::R_HEX_PLT_B22_PCREL) {
helper_PLT_init(pReloc, *this);
rsym->setReserved(rsym->reserved() | ReservePLT);
}
return;
default:
break;
} // end of switch
}
/// defineSymbolforCopyReloc
/// For a symbol needing copy relocation, define a copy symbol in the BSS
/// section and all other reference to this symbol should refer to this
/// copy.
/// @note This is executed at `scan relocation' stage.
LDSymbol& HexagonRelocator::defineSymbolforCopyReloc(
IRBuilder& pBuilder,
const ResolveInfo& pSym,
HexagonLDBackend& pTarget) {
// get or create corresponding BSS LDSection
LDSection* bss_sect_hdr = NULL;
ELFFileFormat* file_format = pTarget.getOutputFormat();
if (ResolveInfo::ThreadLocal == pSym.type())
bss_sect_hdr = &file_format->getTBSS();
else
bss_sect_hdr = &file_format->getBSS();
// get or create corresponding BSS SectionData
assert(bss_sect_hdr != NULL);
SectionData* bss_section = NULL;
if (bss_sect_hdr->hasSectionData())
bss_section = bss_sect_hdr->getSectionData();
else
bss_section = IRBuilder::CreateSectionData(*bss_sect_hdr);
// Determine the alignment by the symbol value
// FIXME: here we use the largest alignment
uint32_t addralign = config().targets().bitclass() / 8;
// allocate space in BSS for the copy symbol
Fragment* frag = new FillFragment(0x0, 1, pSym.size());
uint64_t size = ObjectBuilder::AppendFragment(*frag, *bss_section, addralign);
bss_sect_hdr->setSize(bss_sect_hdr->size() + size);
// change symbol binding to Global if it's a weak symbol
ResolveInfo::Binding binding = (ResolveInfo::Binding)pSym.binding();
if (binding == ResolveInfo::Weak)
binding = ResolveInfo::Global;
// Define the copy symbol in the bss section and resolve it
LDSymbol* cpy_sym = pBuilder.AddSymbol<IRBuilder::Force, IRBuilder::Resolve>(
pSym.name(),
(ResolveInfo::Type)pSym.type(),
ResolveInfo::Define,
binding,
pSym.size(), // size
0x0, // value
FragmentRef::Create(*frag, 0x0),
(ResolveInfo::Visibility)pSym.other());
// output all other alias symbols if any
Module& pModule = pBuilder.getModule();
Module::AliasList* alias_list = pModule.getAliasList(pSym);
if (alias_list != NULL) {
Module::alias_iterator it, it_e = alias_list->end();
for (it = alias_list->begin(); it != it_e; ++it) {
const ResolveInfo* alias = *it;
if (alias != &pSym && alias->isDyn()) {
pBuilder.AddSymbol<IRBuilder::Force, IRBuilder::Resolve>(
alias->name(),
(ResolveInfo::Type)alias->type(),
ResolveInfo::Define,
binding,
alias->size(), // size
0x0, // value
FragmentRef::Create(*frag, 0x0),
(ResolveInfo::Visibility)alias->other());
}
}
}
return *cpy_sym;
}
void HexagonRelocator::partialScanRelocation(Relocation& pReloc,
Module& pModule) {
pReloc.updateAddend();
// if we meet a section symbol
if (pReloc.symInfo()->type() == ResolveInfo::Section) {
LDSymbol* input_sym = pReloc.symInfo()->outSymbol();
// 1. update the relocation target offset
assert(input_sym->hasFragRef());
// 2. get the output LDSection which the symbol defined in
const LDSection& out_sect =
input_sym->fragRef()->frag()->getParent()->getSection();
ResolveInfo* sym_info =
pModule.getSectionSymbolSet().get(out_sect)->resolveInfo();
// set relocation target symbol to the output section symbol's resolveInfo
pReloc.setSymInfo(sym_info);
}
}
//=========================================//
// Each relocation function implementation //
//=========================================//
// R_HEX_NONE
Relocator::Result none(Relocation& pReloc, HexagonRelocator& pParent) {
return Relocator::OK;
}
// R_HEX_32 and its class of relocations use only addend and symbol value
// S + A : result is unsigned truncate.
// Exception: R_HEX_32_6_X : unsigned verify
Relocator::Result applyAbs(Relocation& pReloc) {
Relocator::Address S = pReloc.symValue();
Relocator::DWord A = pReloc.addend();
uint32_t result = (uint32_t)(S + A);
uint32_t bitMask = 0;
uint32_t effectiveBits = 0;
uint32_t alignment = 1;
uint32_t shift = 0;
switch (pReloc.type()) {
case llvm::ELF::R_HEX_LO16:
bitMask = 0x00c03fff;
break;
case llvm::ELF::R_HEX_HI16:
shift = 16;
bitMask = 0x00c03fff;
break;
case llvm::ELF::R_HEX_32:
bitMask = 0xffffffff;
break;
case llvm::ELF::R_HEX_16:
bitMask = 0x0000ffff;
alignment = 2;
break;
case llvm::ELF::R_HEX_8:
bitMask = 0x000000ff;
alignment = 1;
break;
case llvm::ELF::R_HEX_12_X:
bitMask = 0x000007e0;
break;
case llvm::ELF::R_HEX_32_6_X:
bitMask = 0xfff3fff;
shift = 6;
effectiveBits = 26;
break;
case llvm::ELF::R_HEX_16_X:
case llvm::ELF::R_HEX_11_X:
case llvm::ELF::R_HEX_10_X:
case llvm::ELF::R_HEX_9_X:
case llvm::ELF::R_HEX_8_X:
case llvm::ELF::R_HEX_7_X:
case llvm::ELF::R_HEX_6_X:
bitMask = FINDBITMASK(pReloc.target());
break;
default:
// show proper error
fatal(diag::unsupported_relocation) << static_cast<int>(pReloc.type())
<< "mclinker@googlegroups.com";
}
if ((shift != 0) && (result % alignment != 0))
return Relocator::BadReloc;
result >>= shift;
if (effectiveBits) {
uint32_t range = 1 << effectiveBits;
if (result > (range - 1))
return Relocator::Overflow;
}
pReloc.target() |= ApplyMask<uint32_t>(bitMask, result);
return Relocator::OK;
}
// R_HEX_B22_PCREL and its class of relocations, use
// S + A - P : result is signed verify.
// Exception: R_HEX_B32_PCREL_X : signed truncate
// Another Exception: R_HEX_6_PCREL_X is unsigned truncate
Relocator::Result applyRel(Relocation& pReloc, int64_t pResult) {
uint32_t bitMask = 0;
uint32_t effectiveBits = 0;
uint32_t alignment = 1;
uint32_t result;
uint32_t shift = 0;
switch (pReloc.type()) {
case llvm::ELF::R_HEX_B22_PCREL:
bitMask = 0x01ff3ffe;
effectiveBits = 22;
alignment = 4;
shift = 2;
break;
case llvm::ELF::R_HEX_B15_PCREL:
bitMask = 0x00df20fe;
effectiveBits = 15;
alignment = 4;
shift = 2;
break;
case llvm::ELF::R_HEX_B7_PCREL:
bitMask = 0x00001f18;
effectiveBits = 7;
alignment = 4;
shift = 2;
break;
case llvm::ELF::R_HEX_B13_PCREL:
bitMask = 0x00202ffe;
effectiveBits = 13;
alignment = 4;
shift = 2;
break;
case llvm::ELF::R_HEX_B9_PCREL:
bitMask = 0x003000fe;
effectiveBits = 9;
alignment = 4;
shift = 2;
break;
case llvm::ELF::R_HEX_B32_PCREL_X:
bitMask = 0xfff3fff;
shift = 6;
break;
case llvm::ELF::R_HEX_B22_PCREL_X:
bitMask = 0x01ff3ffe;
effectiveBits = 22;
pResult &= 0x3f;
break;
case llvm::ELF::R_HEX_B15_PCREL_X:
bitMask = 0x00df20fe;
effectiveBits = 15;
pResult &= 0x3f;
break;
case llvm::ELF::R_HEX_B13_PCREL_X:
bitMask = 0x00202ffe;
effectiveBits = 13;
pResult &= 0x3f;
break;
case llvm::ELF::R_HEX_B9_PCREL_X:
bitMask = 0x003000fe;
effectiveBits = 9;
pResult &= 0x3f;
break;
case llvm::ELF::R_HEX_B7_PCREL_X:
bitMask = 0x00001f18;
effectiveBits = 7;
pResult &= 0x3f;
break;
case llvm::ELF::R_HEX_32_PCREL:
bitMask = 0xffffffff;
effectiveBits = 32;
break;
case llvm::ELF::R_HEX_6_PCREL_X:
// This is unique since it has a unsigned operand and its truncated
bitMask = FINDBITMASK(pReloc.target());
result = pReloc.addend() + pReloc.symValue() - pReloc.place();
pReloc.target() |= ApplyMask<uint32_t>(bitMask, result);
return Relocator::OK;
default:
// show proper error
fatal(diag::unsupported_relocation) << static_cast<int>(pReloc.type())
<< "mclinker@googlegroups.com";
}
if ((shift != 0) && (pResult % alignment != 0))
return Relocator::BadReloc;
pResult >>= shift;
if (effectiveBits) {
int64_t range = 1LL << (effectiveBits - 1);
if ((pResult > (range - 1)) || (pResult < -range))
return Relocator::Overflow;
}
pReloc.target() |= (uint32_t)ApplyMask<int32_t>(bitMask, pResult);
return Relocator::OK;
}
Relocator::Result relocAbs(Relocation& pReloc, HexagonRelocator& pParent) {
ResolveInfo* rsym = pReloc.symInfo();
Relocator::Address S = pReloc.symValue();
Relocator::DWord A = pReloc.addend();
Relocation* rel_entry = pParent.getRelRelMap().lookUp(pReloc);
bool has_dyn_rel = (rel_entry != NULL);
// if the flag of target section is not ALLOC, we eprform only static
// relocation.
if (0 == (llvm::ELF::SHF_ALLOC &
pReloc.targetRef().frag()->getParent()->getSection().flag())) {
return applyAbs(pReloc);
}
// a local symbol with .rela type relocation
if (rsym->isLocal() && has_dyn_rel) {
rel_entry->setAddend(S + A);
return Relocator::OK;
}
if (!rsym->isLocal()) {
if (rsym->reserved() & HexagonRelocator::ReservePLT) {
S = helper_get_PLT_address(*rsym, pParent);
}
if (has_dyn_rel) {
if (llvm::ELF::R_HEX_32 == pReloc.type() &&
helper_use_relative_reloc(*rsym, pParent)) {
rel_entry->setAddend(S + A);
} else {
rel_entry->setAddend(A);
return Relocator::OK;
}
}
}
return applyAbs(pReloc);
}
Relocator::Result relocPCREL(Relocation& pReloc, HexagonRelocator& pParent) {
ResolveInfo* rsym = pReloc.symInfo();
int64_t result;
Relocator::Address S = pReloc.symValue();
Relocator::DWord A = pReloc.addend();
Relocator::DWord P = pReloc.place();
FragmentRef& target_fragref = pReloc.targetRef();
Fragment* target_frag = target_fragref.frag();
LDSection& target_sect = target_frag->getParent()->getSection();
result = (int64_t)(S + A - P);
// for relocs inside non ALLOC, just apply
if ((llvm::ELF::SHF_ALLOC & target_sect.flag()) == 0) {
return applyRel(pReloc, result);
}
if (!rsym->isLocal()) {
if (rsym->reserved() & HexagonRelocator::ReservePLT) {
S = helper_get_PLT_address(*rsym, pParent);
result = (int64_t)(S + A - P);
applyRel(pReloc, result);
return Relocator::OK;
}
}
return applyRel(pReloc, result);
}
// R_HEX_GPREL16_0 and its class : Unsigned Verify
Relocator::Result relocGPREL(Relocation& pReloc, HexagonRelocator& pParent) {
Relocator::Address S = pReloc.symValue();
Relocator::DWord A = pReloc.addend();
Relocator::DWord GP = pParent.getTarget().getGP();
uint32_t result = (uint32_t)(S + A - GP);
uint32_t shift = 0;
uint32_t alignment = 1;
switch (pReloc.type()) {
case llvm::ELF::R_HEX_GPREL16_0:
break;
case llvm::ELF::R_HEX_GPREL16_1:
shift = 1;
alignment = 2;
break;
case llvm::ELF::R_HEX_GPREL16_2:
shift = 2;
alignment = 4;
break;
case llvm::ELF::R_HEX_GPREL16_3:
shift = 3;
alignment = 8;
break;
default:
// show proper error
fatal(diag::unsupported_relocation) << static_cast<int>(pReloc.type())
<< "mclinker@googlegroups.com";
}
uint32_t range = 1 << 16;
uint32_t bitMask = FINDBITMASK(pReloc.target());
if ((shift != 0) && (result % alignment != 0))
return Relocator::BadReloc;
result >>= shift;
if (result < range - 1) {
pReloc.target() |= ApplyMask<uint32_t>(bitMask, result);
return Relocator::OK;
}
return Relocator::Overflow;
}
// R_HEX_PLT_B22_PCREL: PLT(S) + A - P
Relocator::Result relocPLTB22PCREL(Relocation& pReloc,
HexagonRelocator& pParent) {
// PLT_S depends on if there is a PLT entry.
Relocator::Address PLT_S;
if ((pReloc.symInfo()->reserved() & HexagonRelocator::ReservePLT))
PLT_S = helper_get_PLT_address(*pReloc.symInfo(), pParent);
else
PLT_S = pReloc.symValue();
Relocator::Address P = pReloc.place();
uint32_t bitMask = FINDBITMASK(pReloc.target());
uint32_t result = (PLT_S + pReloc.addend() - P) >> 2;
pReloc.target() = pReloc.target() | ApplyMask<uint32_t>(bitMask, result);
return Relocator::OK;
}
// R_HEX_GOT_LO16 and its class : (G) Signed Truncate
// Exception: R_HEX_GOT_16(_X): signed verify
// Exception: R_HEX_GOT_11_X : unsigned truncate
Relocator::Result relocGOT(Relocation& pReloc, HexagonRelocator& pParent) {
if (!(pReloc.symInfo()->reserved() & HexagonRelocator::ReserveGOT)) {
return Relocator::BadReloc;
}
// set got entry value if needed
HexagonGOTEntry* got_entry = pParent.getSymGOTMap().lookUp(*pReloc.symInfo());
assert(got_entry != NULL);
if (HexagonRelocator::SymVal == got_entry->getValue())
got_entry->setValue(pReloc.symValue());
Relocator::Address GOT_S = helper_get_GOT_address(*pReloc.symInfo(), pParent);
Relocator::Address GOT = pParent.getTarget().getGOTSymbolAddr();
int32_t result = (int32_t)(GOT_S - GOT);
uint32_t effectiveBits = 0;
uint32_t alignment = 1;
uint32_t bitMask = 0;
uint32_t result_u;
uint32_t shift = 0;
switch (pReloc.type()) {
case llvm::ELF::R_HEX_GOT_LO16:
bitMask = 0x00c03fff;
break;
case llvm::ELF::R_HEX_GOT_HI16:
bitMask = 0x00c03fff;
shift = 16;
alignment = 4;
break;
case llvm::ELF::R_HEX_GOT_32:
bitMask = 0xffffffff;
break;
case llvm::ELF::R_HEX_GOT_16:
bitMask = FINDBITMASK(pReloc.target());
effectiveBits = 16;
break;
case llvm::ELF::R_HEX_GOT_32_6_X:
bitMask = 0xfff3fff;
shift = 6;
break;
case llvm::ELF::R_HEX_GOT_16_X:
bitMask = FINDBITMASK(pReloc.target());
effectiveBits = 6;
break;
case llvm::ELF::R_HEX_GOT_11_X:
bitMask = FINDBITMASK(pReloc.target());
result_u = GOT_S - GOT;
pReloc.target() |= ApplyMask<uint32_t>(bitMask, result_u);
return Relocator::OK;
default:
// show proper error
fatal(diag::unsupported_relocation) << static_cast<int>(pReloc.type())
<< "mclinker@googlegroups.com";
}
if ((shift != 0) && (result % alignment != 0))
return Relocator::BadReloc;
result >>= shift;
if (effectiveBits) {
int32_t range = 1 << (effectiveBits - 1);
if ((result > range - 1) || (result < -range))
return Relocator::Overflow;
}
pReloc.target() |= ApplyMask<int32_t>(bitMask, result);
return Relocator::OK;
}
// R_HEX_GOTREL_LO16: and its class of relocs
// (S + A - GOT) : Signed Truncate
Relocator::Result relocGOTREL(Relocation& pReloc, HexagonRelocator& pParent) {
Relocator::Address S = pReloc.symValue();
Relocator::DWord A = pReloc.addend();
Relocator::Address GOT = pParent.getTarget().getGOTSymbolAddr();
uint32_t bitMask = 0;
uint32_t alignment = 1;
uint32_t shift = 0;
uint32_t result = (uint32_t)(S + A - GOT);
switch (pReloc.type()) {
case llvm::ELF::R_HEX_GOTREL_LO16:
bitMask = 0x00c03fff;
break;
case llvm::ELF::R_HEX_GOTREL_HI16:
bitMask = 0x00c03fff;
shift = 16;
alignment = 4;
break;
case llvm::ELF::R_HEX_GOTREL_32:
bitMask = 0xffffffff;
break;
case llvm::ELF::R_HEX_GOTREL_32_6_X:
bitMask = 0x0fff3fff;
shift = 6;
break;
case llvm::ELF::R_HEX_GOTREL_16_X:
case llvm::ELF::R_HEX_GOTREL_11_X:
bitMask = FINDBITMASK(pReloc.target());
break;
default:
// show proper error
fatal(diag::unsupported_relocation) << static_cast<int>(pReloc.type())
<< "mclinker@googlegroups.com";
}
if (result % alignment != 0)
return Relocator::BadReloc;
result >>= shift;
pReloc.target() |= ApplyMask<uint32_t>(bitMask, result);
return Relocator::OK;
}
Relocator::Result unsupported(Relocation& pReloc, HexagonRelocator& pParent) {
return Relocator::Unsupported;
}
} // namespace mcld