void emitCreateCont(IRGS& env) {
auto const resumeOffset = nextBcOff(env);
assertx(!resumed(env));
assertx(curFunc(env)->isGenerator());
if (curFunc(env)->isAsyncGenerator()) PUNT(CreateCont-AsyncGenerator);
// Create the Generator object. CreateCont takes care of copying local
// variables and iterators.
auto const func = curFunc(env);
auto const resumeSk = SrcKey(func, resumeOffset, true);
auto const bind_data = LdBindAddrData { resumeSk, invSPOff(env) + 1 };
auto const resumeAddr = gen(env, LdBindAddr, bind_data);
auto const cont =
gen(env,
CreateCont,
fp(env),
cns(env, func->numSlotsInFrame()),
resumeAddr,
cns(env, resumeOffset));
// The suspend hook will decref the newly created generator if it throws.
auto const contAR =
gen(env,
LdContActRec,
IsAsyncData(curFunc(env)->isAsync()),
cont);
suspendHookE(env, fp(env), contAR, cont);
// Grab caller info from ActRec, free ActRec, store the return value
// and return control to the caller.
gen(env, StRetVal, fp(env), cont);
auto const ret_data = RetCtrlData { offsetToReturnSlot(env), false };
gen(env, RetCtrl, ret_data, sp(env), fp(env));
}
/*
* Attempts to begin inlining, and returns whether or not it successed.
*
* When doing gen-time inlining, we set up a series of IR instructions
* that looks like this:
*
* fp0 = DefFP
* sp = DefSP<offset>
*
* // ... normal stuff happens ...
*
* // FPI region:
* SpillFrame sp, ...
* // ... probably some StStks due to argument expressions
* fp2 = DefInlineFP<func,retBC,retSP,off> sp
*
* // ... callee body ...
*
* InlineReturn fp2
*
* In DCE we attempt to remove the InlineReturn and DefInlineFP instructions if
* they aren't needed.
*/
bool beginInlining(IRGS& env,
unsigned numParams,
const Func* target,
Offset returnBcOffset) {
auto const& fpiStack = env.irb->fpiStack();
assertx(!fpiStack.empty() &&
"Inlining does not support calls with the FPush* in a different Tracelet");
assertx(returnBcOffset >= 0 && "returnBcOffset before beginning of caller");
assertx(curFunc(env)->base() + returnBcOffset < curFunc(env)->past() &&
"returnBcOffset past end of caller");
FTRACE(1, "[[[ begin inlining: {}\n", target->fullName()->data());
SSATmp** params = (SSATmp**)alloca(sizeof(SSATmp*) * numParams);
for (unsigned i = 0; i < numParams; ++i) {
params[numParams - i - 1] = popF(env);
}
auto const prevSP = fpiStack.front().returnSP;
auto const prevSPOff = fpiStack.front().returnSPOff;
spillStack(env);
auto const calleeSP = sp(env);
always_assert_flog(
prevSP == calleeSP,
"FPI stack pointer and callee stack pointer didn't match in beginInlining"
);
auto const& info = fpiStack.front();
always_assert(!isFPushCuf(info.fpushOpc) && !info.interp);
auto ctx = [&] {
if (info.ctx || isFPushFunc(info.fpushOpc)) {
return info.ctx;
}
constexpr int32_t adjust = offsetof(ActRec, m_r) - offsetof(ActRec, m_this);
IRSPOffset ctxOff{invSPOff(env) - info.returnSPOff - adjust};
return gen(env, LdStk, TCtx, IRSPOffsetData{ctxOff}, sp(env));
}();
DefInlineFPData data;
data.target = target;
data.retBCOff = returnBcOffset;
data.fromFPushCtor = isFPushCtor(info.fpushOpc);
data.ctx = ctx;
data.retSPOff = prevSPOff;
data.spOffset = offsetFromIRSP(env, BCSPOffset{0});
// Push state and update the marker before emitting any instructions so
// they're all given markers in the callee.
auto const key = SrcKey {
target,
target->getEntryForNumArgs(numParams),
false
};
env.bcStateStack.emplace_back(key);
env.inlineLevel++;
updateMarker(env);
auto const calleeFP = gen(env, DefInlineFP, data, calleeSP, fp(env));
for (unsigned i = 0; i < numParams; ++i) {
stLocRaw(env, i, calleeFP, params[i]);
}
const bool hasVariadicArg = target->hasVariadicCaptureParam();
for (unsigned i = numParams; i < target->numLocals() - hasVariadicArg; ++i) {
/*
* Here we need to be generating hopefully-dead stores to initialize
* non-parameter locals to KindOfUninit in case we have to leave the trace.
*/
stLocRaw(env, i, calleeFP, cns(env, TUninit));
}
if (hasVariadicArg) {
auto argNum = target->numLocals() - 1;
always_assert(numParams <= argNum);
stLocRaw(env, argNum, calleeFP, cns(env, staticEmptyArray()));
}
return true;
}
