Esempio n. 1
0
void* prepareOSREntry(
    ExecState* exec, CodeBlock* dfgCodeBlock, CodeBlock* entryCodeBlock,
    unsigned bytecodeIndex, unsigned streamIndex)
{
    VM& vm = exec->vm();
    CodeBlock* baseline = dfgCodeBlock->baselineVersion();
    DFG::JITCode* dfgCode = dfgCodeBlock->jitCode()->dfg();
    ForOSREntryJITCode* entryCode = entryCodeBlock->jitCode()->ftlForOSREntry();
    
    if (Options::verboseOSR()) {
        dataLog(
            "FTL OSR from ", *dfgCodeBlock, " to ", *entryCodeBlock, " at bc#",
            bytecodeIndex, ".\n");
    }
    
    if (bytecodeIndex != entryCode->bytecodeIndex()) {
        if (Options::verboseOSR())
            dataLog("    OSR failed because we don't have an entrypoint for bc#", bytecodeIndex, "; ours is for bc#", entryCode->bytecodeIndex());
        return 0;
    }
    
    Operands<JSValue> values;
    dfgCode->reconstruct(
        exec, dfgCodeBlock, CodeOrigin(bytecodeIndex), streamIndex, values);
    
    if (Options::verboseOSR())
        dataLog("    Values at entry: ", values, "\n");
    
    for (int argument = values.numberOfArguments(); argument--;) {
        RELEASE_ASSERT(
            exec->r(virtualRegisterForArgument(argument).offset()).jsValue() == values.argument(argument));
    }
    
    RELEASE_ASSERT(
        static_cast<int>(values.numberOfLocals()) == baseline->m_numCalleeRegisters);
    
    EncodedJSValue* scratch = static_cast<EncodedJSValue*>(
        entryCode->entryBuffer()->dataBuffer());
    
    for (int local = values.numberOfLocals(); local--;)
        scratch[local] = JSValue::encode(values.local(local));
    
    int stackFrameSize = entryCode->common.requiredRegisterCountForExecutionAndExit();
    if (!vm.interpreter->stack().grow(&exec->registers()[virtualRegisterForLocal(stackFrameSize).offset()])) {
        if (Options::verboseOSR())
            dataLog("    OSR failed because stack growth failed.\n");
        return 0;
    }
    
    exec->setCodeBlock(entryCodeBlock);
    
    void* result = entryCode->addressForCall().executableAddress();
    if (Options::verboseOSR())
        dataLog("    Entry will succeed, going to address", RawPointer(result), "\n");
    
    return result;
}
Esempio n. 2
0
SUPPRESS_ASAN
void* prepareOSREntry(
    ExecState* exec, CodeBlock* dfgCodeBlock, CodeBlock* entryCodeBlock,
    unsigned bytecodeIndex, unsigned streamIndex)
{
    VM& vm = exec->vm();
    CodeBlock* baseline = dfgCodeBlock->baselineVersion();
    ExecutableBase* executable = dfgCodeBlock->ownerExecutable();
    DFG::JITCode* dfgCode = dfgCodeBlock->jitCode()->dfg();
    ForOSREntryJITCode* entryCode = entryCodeBlock->jitCode()->ftlForOSREntry();
    
    if (Options::verboseOSR()) {
        dataLog(
            "FTL OSR from ", *dfgCodeBlock, " to ", *entryCodeBlock, " at bc#",
            bytecodeIndex, ".\n");
    }
    
    if (bytecodeIndex)
        jsCast<ScriptExecutable*>(executable)->setDidTryToEnterInLoop(true);

    if (bytecodeIndex != entryCode->bytecodeIndex()) {
        if (Options::verboseOSR())
            dataLog("    OSR failed because we don't have an entrypoint for bc#", bytecodeIndex, "; ours is for bc#", entryCode->bytecodeIndex(), "\n");
        return 0;
    }
    
    Operands<JSValue> values;
    dfgCode->reconstruct(
        exec, dfgCodeBlock, CodeOrigin(bytecodeIndex), streamIndex, values);
    
    if (Options::verboseOSR())
        dataLog("    Values at entry: ", values, "\n");
    
    for (int argument = values.numberOfArguments(); argument--;) {
        JSValue valueOnStack = exec->r(virtualRegisterForArgument(argument).offset()).asanUnsafeJSValue();
        JSValue reconstructedValue = values.argument(argument);
        if (valueOnStack == reconstructedValue || !argument)
            continue;
        dataLog("Mismatch between reconstructed values and the the value on the stack for argument arg", argument, " for ", *entryCodeBlock, " at bc#", bytecodeIndex, ":\n");
        dataLog("    Value on stack: ", valueOnStack, "\n");
        dataLog("    Reconstructed value: ", reconstructedValue, "\n");
        RELEASE_ASSERT_NOT_REACHED();
    }
    
    RELEASE_ASSERT(
        static_cast<int>(values.numberOfLocals()) == baseline->m_numCalleeRegisters);
    
    EncodedJSValue* scratch = static_cast<EncodedJSValue*>(
        entryCode->entryBuffer()->dataBuffer());
    
    for (int local = values.numberOfLocals(); local--;)
        scratch[local] = JSValue::encode(values.local(local));
    
    int stackFrameSize = entryCode->common.requiredRegisterCountForExecutionAndExit();
    if (!vm.interpreter->stack().ensureCapacityFor(&exec->registers()[virtualRegisterForLocal(stackFrameSize - 1).offset()])) {
        if (Options::verboseOSR())
            dataLog("    OSR failed because stack growth failed.\n");
        return 0;
    }
    
    exec->setCodeBlock(entryCodeBlock);
    
    void* result = entryCode->addressForCall(
        vm, executable, ArityCheckNotRequired,
        RegisterPreservationNotRequired).executableAddress();
    if (Options::verboseOSR())
        dataLog("    Entry will succeed, going to address", RawPointer(result), "\n");
    
    return result;
}