#include "config.h"
#include "FTLOSREntry.h"
#include "CallFrame.h"
#include "CodeBlock.h"
#include "DFGJITCode.h"
#include "FTLForOSREntryJITCode.h"
#include "JSCJSValueInlines.h"
#include "OperandsInlines.h"
#include "VMInlines.h"
#if ENABLE(FTL_JIT)
namespace JSC { namespace FTL {
SUPPRESS_ASAN
void* prepareOSREntry(
VM& vm, CallFrame* callFrame, CodeBlock* dfgCodeBlock, CodeBlock* entryCodeBlock,
BytecodeIndex bytecodeIndex, unsigned streamIndex)
{
CodeBlock* baseline = dfgCodeBlock->baselineVersion();
ExecutableBase* executable = dfgCodeBlock->ownerExecutable();
DFG::JITCode* dfgCode = dfgCodeBlock->jitCode()->dfg();
ForOSREntryJITCode* entryCode = entryCodeBlock->jitCode()->ftlForOSREntry();
if (!entryCode->dfgCommon()->isStillValid) {
dfgCode->clearOSREntryBlockAndResetThresholds(dfgCodeBlock);
return nullptr;
}
dataLogLnIf(Options::verboseOSR(),
"FTL OSR from ", *dfgCodeBlock, " to ", *entryCodeBlock, " at ",
bytecodeIndex);
if (bytecodeIndex)
jsCast<ScriptExecutable*>(executable)->setDidTryToEnterInLoop(true);
if (bytecodeIndex != entryCode->bytecodeIndex()) {
dataLogLnIf(Options::verboseOSR(), " OSR failed because we don't have an entrypoint for ", bytecodeIndex, "; ours is for ", entryCode->bytecodeIndex());
return nullptr;
}
Operands<Optional<JSValue>> values;
dfgCode->reconstruct(callFrame, dfgCodeBlock, CodeOrigin(bytecodeIndex), streamIndex, values);
dataLogLnIf(Options::verboseOSR(), " Values at entry: ", values);
Optional<JSValue> reconstructedThis;
for (int argument = values.numberOfArguments(); argument--;) {
JSValue valueOnStack = callFrame->r(virtualRegisterForArgumentIncludingThis(argument)).asanUnsafeJSValue();
Optional<JSValue> reconstructedValue = values.argument(argument);
{
JSValue valueToValidate = reconstructedValue ? *reconstructedValue : valueOnStack;
auto flushFormat = entryCode->argumentFlushFormats()[argument];
switch (flushFormat) {
case DFG::FlushedInt32:
if (!valueToValidate.isInt32())
return nullptr;
break;
case DFG::FlushedBoolean:
if (!valueToValidate.isBoolean())
return nullptr;
break;
case DFG::FlushedCell:
if (!valueToValidate.isCell())
return nullptr;
break;
case DFG::FlushedJSValue:
break;
default:
dataLogLn("Unknown flush format for argument during FTL osr entry: ", flushFormat);
RELEASE_ASSERT_NOT_REACHED();
break;
}
}
if (!argument) {
reconstructedThis = reconstructedValue;
continue;
}
if (reconstructedValue && valueOnStack == reconstructedValue.value())
continue;
dataLog("Mismatch between reconstructed values and the value on the stack for argument arg", argument, " for ", *entryCodeBlock, " at ", bytecodeIndex, ":\n");
dataLog(" Value on stack: ", valueOnStack, "\n");
dataLog(" Reconstructed value: ", reconstructedValue, "\n");
RELEASE_ASSERT_NOT_REACHED();
}
RELEASE_ASSERT(values.numberOfLocals() == baseline->numCalleeLocals());
EncodedJSValue* scratch = static_cast<EncodedJSValue*>(
entryCode->entryBuffer()->dataBuffer());
for (int local = values.numberOfLocals(); local--;) {
Optional<JSValue> value = values.local(local);
if (value)
scratch[local] = JSValue::encode(value.value());
else
scratch[local] = JSValue::encode(JSValue());
}
int stackFrameSize = entryCode->common.requiredRegisterCountForExecutionAndExit();
if (UNLIKELY(!vm.ensureStackCapacityFor(&callFrame->registers()[virtualRegisterForLocal(stackFrameSize - 1).offset()]))) {
dataLogLnIf(Options::verboseOSR(), " OSR failed because stack growth failed.");
return nullptr;
}
callFrame->setCodeBlock(entryCodeBlock);
void* result = entryCode->addressForCall(ArityCheckNotRequired).executableAddress();
dataLogLnIf(Options::verboseOSR(), " Entry will succeed, going to address ", RawPointer(result));
if (result) {
if (reconstructedThis)
callFrame->r(virtualRegisterForArgumentIncludingThis(0)) = JSValue::encode(reconstructedThis.value());
}
return result;
}
} }
#endif // ENABLE(FTL_JIT)