void emitFuncGuard(const Func* func, CodeBlock& cb) {
using namespace reg;
X64Assembler a { cb };
assertx(x64::abi(CodeKind::CrossTrace).gpUnreserved.contains(rax));
TCA start DEBUG_ONLY = a.frontier();
auto const funcImm = Immed64(func);
if (funcImm.fits(sz::dword)) {
emitSmashableCmpq(a.code(), funcImm.l(), rVmFp,
safe_cast<int8_t>(AROFF(m_func)));
} else {
// Although func doesn't fit in a signed 32-bit immediate, it may still fit
// in an unsigned one. Rather than deal with yet another case (which only
// happens when we disable jemalloc), just emit a smashable mov followed by
// a register cmp.
emitSmashableMovq(a.code(), uint64_t(func), rax);
a. cmpq (rax, rVmFp[AROFF(m_func)]);
}
a. jnz (mcg->tx().uniqueStubs.funcPrologueRedispatch);
assertx(funcPrologueToGuard(a.frontier(), func) == start);
assertx(funcPrologueHasGuard(a.frontier(), func));
}
void emitFuncGuard(const Func* func, CodeBlock& cb, CGMeta& fixups) {
using namespace reg;
X64Assembler a { cb };
assertx(x64::abi(CodeKind::CrossTrace).gpUnreserved.contains(rax));
auto const funcImm = Immed64(func);
if (funcImm.fits(sz::dword)) {
emitSmashableCmpq(a.code(), fixups, funcImm.l(), rvmfp(),
safe_cast<int8_t>(AROFF(m_func)));
} else {
// Although func doesn't fit in a signed 32-bit immediate, it may still fit
// in an unsigned one. Rather than deal with yet another case (which only
// happens when we disable jemalloc), just emit a smashable mov followed by
// a register cmp.
emitSmashableMovq(a.code(), fixups, uint64_t(func), rax);
a. cmpq (rax, rvmfp()[AROFF(m_func)]);
}
a. jnz (tc::ustubs().funcPrologueRedispatch);
DEBUG_ONLY auto guard = funcGuardFromPrologue(a.frontier(), func);
assertx(funcGuardMatches(guard, func));
}
void emitFuncGuard(const Func* func, CodeBlock& cb) {
using namespace reg;
X64Assembler a { cb };
assertx(cross_trace_abi.gpUnreserved.contains(rax));
auto const funcImm = Immed64(func);
int nbytes, offset;
if (!funcImm.fits(sz::dword)) {
nbytes = kFuncGuardSmash;
offset = kFuncGuardImm;
} else {
nbytes = kFuncGuardShortSmash;
offset = kFuncGuardShortImm;
}
mcg->backEnd().prepareForSmash(a.code(), nbytes, offset);
TCA start DEBUG_ONLY = a.frontier();
if (!funcImm.fits(sz::dword)) {
// Although func doesnt fit in a signed 32-bit immediate, it may still fit
// in an unsigned one. Rather than deal with yet another case (which only
// happens when we disable jemalloc), just force it to be an 8-byte
// immediate, and patch it up afterwards.
a. movq (0xdeadbeeffeedface, rax);
auto immptr = reinterpret_cast<uintptr_t*>(a.frontier()) - 1;
assertx(*immptr == 0xdeadbeeffeedface);
*immptr = uintptr_t(func);
a. cmpq (rax, rVmFp[AROFF(m_func)]);
} else {
a. cmpq (funcImm.l(), rVmFp[AROFF(m_func)]);
}
a. jnz (mcg->tx().uniqueStubs.funcPrologueRedispatch);
assertx(funcPrologueToGuard(a.frontier(), func) == start);
assertx(funcPrologueHasGuard(a.frontier(), func));
}
void PhysRegSaverParity::emitPops(X64Assembler& as, RegSet regs) {
emitPops(Vauto(as.code()).main(), regs);
}
PhysRegSaverParity::PhysRegSaverParity(int parity, X64Assembler& as,
RegSet regs)
: PhysRegSaverParity{parity, Vauto(as.code()).main(), regs} {
m_v = nullptr;
m_as = &as;
}
