static bool isMainExit(const Block* b) {
if (b->hint() == Block::Hint::Unlikely) return false;
if (b->next()) return false;
auto taken = b->taken();
if (!taken) return true;
if (taken->isCatch()) return true;
return false;
}
/*
* Whether the block appears to be the exit block of the main code
* path of a region. This is conservative, so it may return false on
* all blocks in a region.
*/
static bool isMainExit(const Block* b) {
if (!isMainBlock(b)) return false;
if (b->next()) return false;
// The Await bytecode instruction does a RetCtrl to the scheduler,
// which is in a likely block. We don't want to consider this as
// the main exit.
auto const& back = b->back();
if (back.op() == RetCtrl && back.marker().sk().op() == OpAwait) return false;
auto const taken = b->taken();
return !taken || taken->isCatch();
}
/*
* Unit
*/
void print(std::ostream& os, const IRUnit& unit, const AsmInfo* asmInfo,
const GuardConstraints* guards) {
// For nice-looking dumps, we want to remember curMarker between blocks.
BCMarker curMarker;
static bool dotBodies = getenv("HHIR_DOT_BODIES");
auto blocks = rpoSortCfg(unit);
// Partition into main, cold and frozen, without changing relative order.
auto cold = std::stable_partition(blocks.begin(), blocks.end(),
[&] (Block* b) {
return b->hint() == Block::Hint::Neither ||
b->hint() == Block::Hint::Likely;
}
);
auto frozen = std::stable_partition(cold, blocks.end(),
[&] (Block* b) {
return b->hint() == Block::Hint::Unlikely;
}
);
if (dumpIREnabled(kExtraExtraLevel)) printOpcodeStats(os, blocks);
// Print the block CFG above the actual code.
auto const retreating_edges = findRetreatingEdges(unit);
os << "digraph G {\n";
for (auto block : blocks) {
if (block->empty()) continue;
if (dotBodies && block->hint() != Block::Hint::Unlikely &&
block->hint() != Block::Hint::Unused) {
// Include the IR in the body of the node
std::ostringstream out;
print(out, block, AreaIndex::Main, asmInfo, guards, &curMarker);
auto bodyRaw = out.str();
std::string body;
body.reserve(bodyRaw.size() * 1.25);
for (auto c : bodyRaw) {
if (c == '\n') body += "\\n";
else if (c == '"') body += "\\\"";
else if (c == '\\') body += "\\\\";
else body += c;
}
os << folly::format("B{} [shape=\"box\" label=\"{}\"]\n",
block->id(), body);
}
auto next = block->nextEdge();
auto taken = block->takenEdge();
if (!next && !taken) continue;
auto edge_color = [&] (Edge* edge) {
auto const target = edge->to();
return
target->isCatch() ? " [color=blue]" :
target->isExit() ? " [color=cyan]" :
retreating_edges.count(edge) ? " [color=red]" :
target->hint() == Block::Hint::Unlikely ? " [color=green]" : "";
};
auto show_edge = [&] (Edge* edge) {
os << folly::format(
"B{} -> B{}{}",
block->id(),
edge->to()->id(),
edge_color(edge)
);
};
if (next) {
show_edge(next);
if (taken) os << "; ";
}
if (taken) show_edge(taken);
os << "\n";
}
os << "}\n";
AreaIndex currentArea = AreaIndex::Main;
curMarker = BCMarker();
for (auto it = blocks.begin(); it != blocks.end(); ++it) {
if (it == cold) {
os << folly::format("\n{:-^60}", "cold blocks");
currentArea = AreaIndex::Cold;
}
if (it == frozen) {
os << folly::format("\n{:-^60}", "frozen blocks");
currentArea = AreaIndex::Frozen;
}
print(os, *it, currentArea, asmInfo, guards, &curMarker);
}
}
