/**
* Add to sets coveredNodes and coveredArcs the cfg arcs that are now
* covered given the new region containing the translations in
* selectedVec.
*/
static void markCovered(const TransCFG& cfg, const RegionDescPtr region,
const TransIDVec& selectedVec, const TransIDSet heads,
TransIDSet& coveredNodes,
TransCFG::ArcPtrSet& coveredArcs) {
assert(selectedVec.size() > 0);
TransID newHead = selectedVec[0];
assert(!region->empty());
assert(newHead == getTransId(region->entry()->id()));
// Mark all region's nodes as covered.
coveredNodes.insert(selectedVec.begin(), selectedVec.end());
// Mark all incoming arcs into newHead from covered nodes as covered.
for (auto arc : cfg.inArcs(newHead)) {
TransID src = arc->src();
if (coveredNodes.count(src)) {
coveredArcs.insert(arc);
}
}
// Mark all CFG arcs within the region as covered.
region->forEachArc([&](RegionDesc::BlockId src, RegionDesc::BlockId dst) {
if (!hasTransId(src) || !hasTransId(dst)) return;
TransID srcTid = getTransId(src);
TransID dstTid = getTransId(dst);
assert(cfg.hasArc(srcTid, dstTid));
bool foundArc = false;
for (auto arc : cfg.outArcs(srcTid)) {
if (arc->dst() == dstTid) {
coveredArcs.insert(arc);
foundArc = true;
}
}
always_assert(foundArc);
});
// Mark all outgoing arcs from the region to a head node as covered.
for (auto node : selectedVec) {
for (auto arc : cfg.outArcs(node)) {
if (heads.count(arc->dst())) {
coveredArcs.insert(arc);
}
}
}
}
static bool allArcsCovered(const TransCFG::ArcPtrVec& arcs,
const TransCFG::ArcPtrSet& coveredArcs) {
for (auto arc : arcs) {
if (!coveredArcs.count(arc)) {
return false;
}
}
return true;
}
/**
* Add to sets coveredNodes and coveredArcs the cfg arcs that are now
* covered given the new region containing the translations in
* selectedVec.
*/
static void markCovered(const TransCFG& cfg, const TransIDVec selectedVec,
const TransIDSet heads, TransIDSet& coveredNodes,
TransCFG::ArcPtrSet& coveredArcs) {
assert(selectedVec.size() > 0);
TransID newHead = selectedVec[0];
// Mark all region's nodes as covered.
coveredNodes.insert(selectedVec.begin(), selectedVec.end());
// Mark all incoming arcs into newHead from covered nodes as covered.
for (auto arc : cfg.inArcs(newHead)) {
TransID src = arc->src();
if (coveredNodes.count(src)) {
coveredArcs.insert(arc);
}
}
// Mark all arcs between consecutive region nodes as covered.
for (size_t i = 0; i < selectedVec.size() - 1; i++) {
TransID node = selectedVec[i];
TransID next = selectedVec[i + 1];
bool foundArc = false;
for (auto arc : cfg.outArcs(node)) {
if (arc->dst() == next) {
coveredArcs.insert(arc);
foundArc = true;
}
}
always_assert(foundArc);
}
// Mark all outgoing arcs from the region to a head node as covered.
for (auto node : selectedVec) {
for (auto arc : cfg.outArcs(node)) {
if (heads.count(arc->dst())) {
coveredArcs.insert(arc);
}
}
}
}
/**
* Regionize a func, so that each node and each arc in its TransCFG is
* "covered". A node is covered if any region contains it. An arc T1->T2
* is covered if either:
*
* a) T1 and T2 are in the same region R and T2 immediately follows
* T1 in R.
* b) T2 is the head (first translation) of a region.
*
* Basic algorithm:
*
* 1) sort nodes in decreasing weight order
* 2) for each node N:
* 2.1) if N and all its incoming arcs are covered, then continue
* 2.2) select a region starting at this node and mark nodes/arcs as
* covered appropriately
*/
void regionizeFunc(const Func* func,
MCGenerator* mcg,
RegionVec& regions) {
const Timer rf_timer(Timer::regionizeFunc);
assert(RuntimeOption::EvalJitPGO);
auto const funcId = func->getFuncId();
auto const profData = mcg->tx().profData();
TransCFG cfg(funcId, profData, mcg->tx().getSrcDB(),
mcg->getJmpToTransIDMap());
if (Trace::moduleEnabled(HPHP::Trace::pgo, 5)) {
auto dotFileName = folly::to<std::string>(
"/tmp/func-cfg-", funcId, ".dot");
cfg.print(dotFileName, funcId, profData, nullptr);
FTRACE(5, "regionizeFunc: initial CFG for func {} saved to file {}\n",
funcId, dotFileName);
}
TransCFG::ArcPtrVec arcs = cfg.arcs();
std::vector<TransID> nodes = cfg.nodes();
std::sort(nodes.begin(), nodes.end(),
[&](TransID tid1, TransID tid2) -> bool {
if (RuntimeOption::EvalJitPGORegionSelector == "wholecfg") {
auto bcOff1 = profData->transStartBcOff(tid1);
auto bcOff2 = profData->transStartBcOff(tid2);
if (bcOff1 != bcOff2) return bcOff1 < bcOff2;
}
if (cfg.weight(tid1) != cfg.weight(tid2)) {
return cfg.weight(tid1) > cfg.weight(tid2);
}
// In case of ties, pick older translations first, in an
// attempt to start loops at their headers.
return tid1 < tid2;
});
TransCFG::ArcPtrSet coveredArcs;
TransIDSet coveredNodes;
TransIDSet heads;
TransIDToRegionMap headToRegion;
RegionToTransIDsMap regionToTransIds;
regions.clear();
for (auto node : nodes) {
if (!coveredNodes.count(node) ||
!allArcsCovered(cfg.inArcs(node), coveredArcs)) {
TransID newHead = node;
FTRACE(6, "regionizeFunc: selecting trace to cover node {}\n", newHead);
TransIDSet selectedSet;
TransIDVec selectedVec;
RegionDescPtr region;
if (RuntimeOption::EvalJitPGORegionSelector == "hottrace") {
region = selectHotTrace(newHead, profData, cfg,
selectedSet, &selectedVec);
} else if (RuntimeOption::EvalJitPGORegionSelector == "wholecfg") {
region = selectWholeCFG(newHead, profData, cfg, selectedSet,
&selectedVec);
} else {
always_assert(0 && "Invalid value for EvalJitPGORegionSelector");
}
FTRACE(6, "regionizeFunc: selected region to cover node {}\n{}\n",
newHead, show(*region));
profData->setOptimized(profData->transSrcKey(newHead));
assert(selectedVec.size() > 0 && selectedVec[0] == newHead);
regions.push_back(region);
heads.insert(newHead);
markCovered(cfg, region, selectedVec, heads, coveredNodes, coveredArcs);
regionToTransIds[region] = selectedVec;
headToRegion[newHead] = region;
FTRACE(6, "regionizeFunc: selected trace: {}\n",
folly::join(", ", selectedVec));
}
}
assert(coveredNodes.size() == cfg.nodes().size());
assert(coveredArcs.size() == arcs.size());
sortRegions(regions, func, cfg, profData, headToRegion, regionToTransIds);
if (debug && Trace::moduleEnabled(HPHP::Trace::pgo, 5)) {
FTRACE(5, "\n--------------------------------------------\n"
"regionizeFunc({}): computed regions:\n", funcId);
for (auto region : regions) {
FTRACE(5, "{}\n\n", show(*region));
}
}
}
/**
* Regionize a func, so that each node and each arc in its TransCFG is
* "covered". A node is covered if any region contains it. An arc T1->T2
* is covered if either:
*
* a) T1 and T2 are in the same region R and T2 immediately follows
* T1 in R.
* b) T2 is the head (first translation) of a region.
*
* Basic algorithm:
*
* 1) sort nodes in decreasing weight order
* 2) for each node N:
* 2.1) if N and all its incoming arcs are covered, then continue
* 2.2) select a region starting at this node and mark nodes/arcs as
* covered appropriately
*/
void regionizeFunc(const Func* func,
Transl::TranslatorX64* tx64,
RegionVec& regions) {
assert(RuntimeOption::EvalJitPGO);
FuncId funcId = func->getFuncId();
ProfData* profData = tx64->profData();
TransCFG cfg(funcId, profData, tx64->getSrcDB(), tx64->getJmpToTransIDMap());
if (Trace::moduleEnabled(HPHP::Trace::pgo, 5)) {
string dotFileName = folly::to<string>("/tmp/func-cfg-", funcId, ".dot");
cfg.print(dotFileName, funcId, profData, nullptr);
FTRACE(5, "regionizeFunc: initial CFG for func {} saved to file {}\n",
funcId, dotFileName);
}
TransCFG::ArcPtrVec arcs = cfg.arcs();
vector<TransID> nodes = cfg.nodes();
std::sort(nodes.begin(), nodes.end(),
[&](TransID tid1, TransID tid2) -> bool {
if (cfg.weight(tid1) != cfg.weight(tid2)) {
return cfg.weight(tid1) > cfg.weight(tid2);
}
// In case of ties, pick older translations first, in an
// attempt to start loops at their headers.
return tid1 < tid2;
});
TransCFG::ArcPtrSet coveredArcs;
TransIDSet coveredNodes;
TransIDSet heads;
TransIDToRegionMap headToRegion;
RegionToTransIDsMap regionToTransIds;
regions.clear();
for (auto node : nodes) {
if (!setContains(coveredNodes, node) ||
!allArcsCovered(cfg.inArcs(node), coveredArcs)) {
TransID newHead = node;
FTRACE(6, "regionizeFunc: selecting trace to cover node {}\n", newHead);
TransIDSet selectedSet;
TransIDVec selectedVec;
RegionDescPtr region = selectHotTrace(newHead, profData, cfg,
selectedSet, &selectedVec);
profData->setOptimized(profData->transSrcKey(newHead));
assert(selectedVec.size() > 0 && selectedVec[0] == newHead);
regions.push_back(region);
heads.insert(newHead);
markCovered(cfg, selectedVec, heads, coveredNodes, coveredArcs);
regionToTransIds[region] = selectedVec;
headToRegion[newHead] = region;
FTRACE(6, "regionizeFunc: selected trace: {}\n",
folly::join(", ", selectedVec));
}
}
assert(coveredNodes.size() == cfg.nodes().size());
assert(coveredArcs.size() == arcs.size());
sortRegion(regions, func, cfg, profData, headToRegion, regionToTransIds);
if (debug && Trace::moduleEnabled(HPHP::Trace::pgo, 5)) {
FTRACE(5, "\n--------------------------------------------\n"
"regionizeFunc({}): computed regions:\n", funcId);
for (auto region : regions) {
FTRACE(5, "{}\n\n", show(*region));
}
}
}