#include "config.h"
#include "DFGCFAPhase.h"
#if ENABLE(DFG_JIT)
#include "DFGAbstractInterpreterInlines.h"
#include "DFGGraph.h"
#include "DFGInPlaceAbstractState.h"
#include "DFGPhase.h"
#include "DFGSafeToExecute.h"
#include "OperandsInlines.h"
#include "JSCInlines.h"
namespace JSC { namespace DFG {
class CFAPhase : public Phase {
public:
CFAPhase(Graph& graph)
: Phase(graph, "control flow analysis")
, m_state(graph)
, m_interpreter(graph, m_state)
, m_verbose(Options::verboseCFA())
{
}
bool run()
{
ASSERT(m_graph.m_form == ThreadedCPS || m_graph.m_form == SSA);
ASSERT(m_graph.m_unificationState == GloballyUnified);
ASSERT(m_graph.m_refCountState == EverythingIsLive);
m_count = 0;
if (m_verbose && !shouldDumpGraphAtEachPhase()) {
dataLog("Graph before CFA:\n");
m_graph.dump();
}
m_state.initialize();
do {
m_changed = false;
performForwardCFA();
} while (m_changed);
return true;
}
private:
void performBlockCFA(BasicBlock* block)
{
if (!block)
return;
if (!block->cfaShouldRevisit)
return;
if (m_verbose)
dataLog(" Block ", *block, ":\n");
m_state.beginBasicBlock(block);
if (m_verbose)
dataLog(" head vars: ", block->valuesAtHead, "\n");
for (unsigned i = 0; i < block->size(); ++i) {
if (m_verbose) {
Node* node = block->at(i);
dataLogF(" %s @%u: ", Graph::opName(node->op()), node->index());
if (!safeToExecute(m_state, m_graph, node))
dataLog("(UNSAFE) ");
m_interpreter.dump(WTF::dataFile());
if (m_state.haveStructures())
dataLog(" (Have Structures)");
dataLogF("\n");
}
if (!m_interpreter.execute(i)) {
if (m_verbose)
dataLogF(" Expect OSR exit.\n");
break;
}
}
if (m_verbose) {
dataLogF(" tail regs: ");
m_interpreter.dump(WTF::dataFile());
dataLogF("\n");
}
m_changed |= m_state.endBasicBlock(MergeToSuccessors);
if (m_verbose)
dataLog(" tail vars: ", block->valuesAtTail, "\n");
}
void performForwardCFA()
{
++m_count;
if (m_verbose)
dataLogF("CFA [%u]\n", ++m_count);
for (BlockIndex blockIndex = 0; blockIndex < m_graph.numBlocks(); ++blockIndex)
performBlockCFA(m_graph.block(blockIndex));
}
private:
InPlaceAbstractState m_state;
AbstractInterpreter<InPlaceAbstractState> m_interpreter;
bool m_verbose;
bool m_changed;
unsigned m_count;
};
bool performCFA(Graph& graph)
{
SamplingRegion samplingRegion("DFG CFA Phase");
return runPhase<CFAPhase>(graph);
}
} }
#endif // ENABLE(DFG_JIT)