You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
117 lines
3.3 KiB
117 lines
3.3 KiB
//===- ARMToTHMStub.cpp ---------------------------------------------------===//
|
|
//
|
|
// The MCLinker Project
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "ARMToTHMStub.h"
|
|
#include "ARMLDBackend.h"
|
|
|
|
#include "mcld/Fragment/Relocation.h"
|
|
#include "mcld/LD/LDSymbol.h"
|
|
#include "mcld/LD/ResolveInfo.h"
|
|
|
|
#include <llvm/Support/ELF.h>
|
|
|
|
namespace mcld {
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// ARMToTHMStub
|
|
//===----------------------------------------------------------------------===//
|
|
const uint32_t ARMToTHMStub::PIC_TEMPLATE[] = {
|
|
0xe59fc004, // ldr r12, [pc, #4]
|
|
0xe08fc00c, // add ip, pc, ip
|
|
0xe12fff1c, // bx ip
|
|
0x0 // dcd R_ARM_REL32(X)
|
|
};
|
|
|
|
const uint32_t ARMToTHMStub::TEMPLATE[] = {
|
|
0xe59fc000, // ldr ip, [pc, #0]
|
|
0xe12fff1c, // bx ip
|
|
0x0 // dcd R_ARM_ABS32(X)
|
|
};
|
|
|
|
ARMToTHMStub::ARMToTHMStub(bool pIsOutputPIC)
|
|
: m_pData(NULL), m_Name("A2T_prototype"), m_Size(0x0) {
|
|
if (pIsOutputPIC) {
|
|
m_pData = PIC_TEMPLATE;
|
|
m_Size = sizeof(PIC_TEMPLATE);
|
|
addFixup(12u, 0x0, llvm::ELF::R_ARM_REL32);
|
|
} else {
|
|
m_pData = TEMPLATE;
|
|
m_Size = sizeof(TEMPLATE);
|
|
addFixup(8u, 0x0, llvm::ELF::R_ARM_ABS32);
|
|
}
|
|
}
|
|
|
|
/// for doClone
|
|
ARMToTHMStub::ARMToTHMStub(const uint32_t* pData,
|
|
size_t pSize,
|
|
const_fixup_iterator pBegin,
|
|
const_fixup_iterator pEnd)
|
|
: m_pData(pData), m_Name("A2T_veneer"), m_Size(pSize) {
|
|
for (const_fixup_iterator it = pBegin, ie = pEnd; it != ie; ++it)
|
|
addFixup(**it);
|
|
}
|
|
|
|
ARMToTHMStub::~ARMToTHMStub() {
|
|
}
|
|
|
|
bool ARMToTHMStub::isMyDuty(const class Relocation& pReloc,
|
|
uint64_t pSource,
|
|
uint64_t pTargetSymValue) const {
|
|
bool result = false;
|
|
// Check if the branch target is THUMB
|
|
if ((pTargetSymValue & 0x1) != 0x0) {
|
|
switch (pReloc.type()) {
|
|
case llvm::ELF::R_ARM_CALL: {
|
|
// FIXME: Assuming blx is available (i.e., target is armv5 or above!)
|
|
// then, we do not need a stub unless the branch target is too far.
|
|
uint64_t dest = pTargetSymValue + pReloc.addend() + 8u;
|
|
int64_t branch_offset = static_cast<int64_t>(dest) - pSource;
|
|
if ((branch_offset > ARMGNULDBackend::ARM_MAX_FWD_BRANCH_OFFSET) ||
|
|
(branch_offset < ARMGNULDBackend::ARM_MAX_BWD_BRANCH_OFFSET)) {
|
|
result = true;
|
|
break;
|
|
}
|
|
break;
|
|
}
|
|
case llvm::ELF::R_ARM_PC24:
|
|
case llvm::ELF::R_ARM_JUMP24:
|
|
case llvm::ELF::R_ARM_PLT32: {
|
|
// always need a stub to switch mode
|
|
result = true;
|
|
break;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
const std::string& ARMToTHMStub::name() const {
|
|
return m_Name;
|
|
}
|
|
|
|
const uint8_t* ARMToTHMStub::getContent() const {
|
|
return reinterpret_cast<const uint8_t*>(m_pData);
|
|
}
|
|
|
|
size_t ARMToTHMStub::size() const {
|
|
return m_Size;
|
|
}
|
|
|
|
size_t ARMToTHMStub::alignment() const {
|
|
return 4u;
|
|
}
|
|
|
|
Stub* ARMToTHMStub::doClone() {
|
|
return new ARMToTHMStub(m_pData, m_Size, fixup_begin(), fixup_end());
|
|
}
|
|
|
|
} // namespace mcld
|