void SrcRec::chainFrom(IncomingBranch br) {
assert(br.type() == IncomingBranch::Tag::ADDR ||
mcg->code.isValidCodeAddress(br.toSmash()));
TCA destAddr = getTopTranslation();
m_incomingBranches.push_back(br);
TRACE(1, "SrcRec(%p)::chainFrom %p -> %p (type %d); %zd incoming branches\n",
this,
br.toSmash(), destAddr, br.type(), m_incomingBranches.size());
br.patch(destAddr);
}
void SrcRec::chainFrom(IncomingBranch br) {
assertx(br.type() == IncomingBranch::Tag::ADDR ||
tc::isValidCodeAddress(br.toSmash()));
TCA destAddr = getTopTranslation();
m_incomingBranches.push_back(br);
TRACE(1, "SrcRec(%p)::chainFrom %p -> %p (type %d); %zd incoming branches\n",
this,
br.toSmash(), destAddr, static_cast<int>(br.type()),
m_incomingBranches.size());
br.patch(destAddr);
if (RuntimeOption::EvalEnableReusableTC) {
tc::recordJump(br.toSmash(), this);
}
}
TCA bindAddr(TCA toSmash, SrcKey destSk, TransFlags trflags, bool& smashed) {
auto const sr = srcDB().find(destSk);
always_assert(sr);
auto const tDest = sr->getTopTranslation();
if (tDest == nullptr) return nullptr;
auto codeLock = lockCode();
auto addr = reinterpret_cast<TCA*>(toSmash);
if (*addr == tDest) {
// Already smashed
return tDest;
}
sr->chainFrom(IncomingBranch::addr(addr));
smashed = true;
return tDest;
}
TCA bindJmp(TCA toSmash, SrcKey destSk, TransFlags trflags, bool& smashed) {
auto const sr = srcDB().find(destSk);
always_assert(sr);
auto const tDest = sr->getTopTranslation();
if (tDest == nullptr) return nullptr;
auto codeLock = lockCode();
auto const isJcc = [&] {
switch (arch()) {
case Arch::X64: {
x64::DecodedInstruction di(toSmash);
return (di.isBranch() && !di.isJmp());
}
case Arch::ARM: {
auto instr = reinterpret_cast<vixl::Instruction*>(toSmash);
return instr->IsCondBranchImm();
}
case Arch::PPC64:
ppc64_asm::DecodedInstruction di(toSmash);
return (di.isBranch() && !di.isJmp());
}
not_reached();
}();
if (isJcc) {
auto const target = smashableJccTarget(toSmash);
assertx(target);
// Return if already smashed.
if (target == tDest) return tDest;
sr->chainFrom(IncomingBranch::jccFrom(toSmash));
} else {
auto const target = smashableJmpTarget(toSmash);
assertx(target);
// Return if already smashed.
if (!target || target == tDest) return tDest;
sr->chainFrom(IncomingBranch::jmpFrom(toSmash));
}
smashed = true;
return tDest;
}
