size_t TemplateBuilder::addUse(const TemplateInst& templateInst) {
assert(!templateInst.arguments().empty());
const auto existingId = getUse(templateInst);
if (existingId) {
return existingId.value();
}
const size_t nextId = templateUseMap_.size();
templateUseMap_.insert(std::make_pair(templateInst.copy(), nextId));
const auto arguments = templateInst.arguments();
const auto objectTemplateVars = object_.templateVariables();
if (arguments.size() == objectTemplateVars.size() &&
templateInst.allArgumentsAreTemplateVars(objectTemplateVars)) {
// If we're passing our own template arguments to
// something else unchanged, then we could apply
// the 'pass-through optimisation', which effectively
// means we don't need to allocate any space on
// the path and just call directly down to the
// next template generator.
//
// Note that this only works if there's exaclty
// one template call, hence it's just considered
// a 'candidate' at this point.
isPassThroughOptimisationCandidate_ = true;
}
for (const auto& arg: arguments) {
if (arg.isTypeRef()) {
const auto typeArg = arg.typeRefType();
if (typeArg->isObject() && !typeArg->templateArguments().empty()) {
(void) addUse(TemplateInst::Type(typeArg));
}
}
}
return nextId;
}
//
// Attempts to replace references with the variables the references point to,
// provided the references have a single definition.
//
// For example:
// var foo : int;
// ref A : int;
// (move A (addr-of foo))
//
// (move B (deref A)) ---> (move B foo)
//
void
eliminateSingleAssignmentReference(Map<Symbol*,Vec<SymExpr*>*>& defMap,
Map<Symbol*,Vec<SymExpr*>*>& useMap,
Symbol* var) {
if (CallExpr* move = findRefDef(defMap, var)) {
if (CallExpr* rhs = toCallExpr(move->get(2))) {
if (rhs->isPrimitive(PRIM_ADDR_OF) || rhs->isPrimitive(PRIM_SET_REFERENCE)) {
bool stillAlive = false;
for_uses(se, useMap, var) {
CallExpr* parent = toCallExpr(se->parentExpr);
SET_LINENO(se);
if (parent && (parent->isPrimitive(PRIM_DEREF) || isDerefMove(parent))) {
SymExpr* se = toSymExpr(rhs->get(1)->copy());
INT_ASSERT(se);
Expr* toReplace = parent;
if (isMoveOrAssign(parent)) {
toReplace = parent->get(2);
}
toReplace->replace(se);
++s_ref_repl_count;
addUse(useMap, se);
} else if (parent &&
(parent->isPrimitive(PRIM_GET_MEMBER_VALUE) ||
parent->isPrimitive(PRIM_GET_MEMBER) ||
parent->isPrimitive(PRIM_GET_MEMBER_VALUE) ||
parent->isPrimitive(PRIM_GET_MEMBER))) {
SymExpr* se = toSymExpr(rhs->get(1)->copy());
INT_ASSERT(se);
parent->get(1)->replace(se);
++s_ref_repl_count;
addUse(useMap, se);
}
else if (parent && (parent->isPrimitive(PRIM_MOVE) || parent->isPrimitive(PRIM_SET_REFERENCE))) {
CallExpr* rhsCopy = rhs->copy();
if (parent->isPrimitive(PRIM_SET_REFERENCE)) {
// Essentially a pointer copy like a (move refA refB)
parent = toCallExpr(parent->parentExpr);
INT_ASSERT(parent && isMoveOrAssign(parent));
}
parent->get(2)->replace(rhsCopy);
++s_ref_repl_count;
SymExpr* se = toSymExpr(rhsCopy->get(1));
INT_ASSERT(se);
addUse(useMap, se);
// BHARSH TODO: Is it possible to handle the following case safely
// for PRIM_ASSIGN?
//
// ref i_foo : T;
// (move i_foo (set reference bar))
// (= call_tmp i_foo)
//
// Should that turn into (= call_tmp bar)?
} else if (parent && parent->isPrimitive(PRIM_ASSIGN) && parent->get(1) == se) {
// for_defs should handle this case
} else if (parent && parent->isResolved()) {
stillAlive = true;
// TODO -- a reference argument can be passed directly
} else {
stillAlive = true;
}
}
for_defs(se, defMap, var) {
CallExpr* parent = toCallExpr(se->parentExpr);
SET_LINENO(se);
if (parent == move)
continue;
if (parent && isMoveOrAssign(parent)) {
SymExpr* se = toSymExpr(rhs->get(1)->copy());
INT_ASSERT(se);
parent->get(1)->replace(se);
++s_ref_repl_count;
addDef(defMap, se);
} else
stillAlive = true;
}
if (!stillAlive) {
var->defPoint->remove();
Vec<SymExpr*>* defs = defMap.get(var);
if (defs == NULL) {
INT_FATAL(var, "Expected var to be defined");
}
// Remove the first definition from the AST.
defs->v[0]->getStmtExpr()->remove();
}
} else if (rhs->isPrimitive(PRIM_GET_MEMBER) ||
