Use UNLIKELY() macro in generated bindings for minimum argument count checks

Source/bindings/scripts/deprecated_code_generator_v8.pm

 # Copyright (C) 2005, 2006 Nikolas Zimmermann <zimmermann@kde.org>
 # Copyright (C) 2006 Anders Carlsson <andersca@mac.com>
 # Copyright (C) 2006 Samuel Weinig <sam.weinig@gmail.com>
 # Copyright (C) 2006 Alexey Proskuryakov <ap@webkit.org>
 # Copyright (C) 2006 Apple Computer, Inc.
 # Copyright (C) 2007, 2008, 2009, 2012 Google Inc.
 # Copyright (C) 2009 Cameron McCormack <cam@mcc.id.au>
 # Copyright (C) Research In Motion Limited 2010. All rights reserved.
 # Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
 # Copyright (C) 2012 Ericsson AB. All rights reserved.
@@ skipping 2067 matching lines @@
     foreach my $overload (@{$function->{overloads}}) {
         my ($numMandatoryParams, $parametersCheck) = GenerateFunctionParametersCheck($overload);
         $leastNumMandatoryParams = $numMandatoryParams if ($numMandatoryParams < $leastNumMandatoryParams);
         $code .= "    if ($parametersCheck) {\n";
         my $overloadedIndexString = $overload->{overloadIndex};
         $code .= "        ${name}${overloadedIndexString}Method${forMainWorldSuffix}(args);\n";
         $code .= "        return;\n";
         $code .= "    }\n";
     }
     if ($leastNumMandatoryParams >= 1) {
-        $code .= "    if (args.Length() < $leastNumMandatoryParams) {\n";
+        $code .= "    if (UNLIKELY(args.Length() < $leastNumMandatoryParams)) {\n";
         $code .= "        throwNotEnoughArgumentsError(args.GetIsolate());\n";
         $code .= "        return;\n";
         $code .= "    }\n";
     }
     $code .= <<END;
     throwTypeError(args.GetIsolate());
 END
     $code .= "}\n\n";
     $code .= "#endif // ${conditionalString}\n\n" if $conditionalString;
     $implementation{nameSpaceInternal}->add($code);
@@ skipping 220 matching lines @@
         if ($param->isOptional or $param->isVariadic) {
             $allowNonOptional = 0;
         } else {
             die "An argument must not be declared to be optional unless all subsequent arguments to the operation are also optional." if !$allowNonOptional;
             $numMandatoryParams++;
         }
     }
 
     my $argumentsCountCheckString = "";
     if ($numMandatoryParams >= 1) {
-        $argumentsCountCheckString .= "    if (args.Length() < $numMandatoryParams) {\n";
+        $argumentsCountCheckString .= "    if (UNLIKELY(args.Length() < $numMandatoryParams)) {\n";
         $argumentsCountCheckString .= "        throwNotEnoughArgumentsError(args.GetIsolate());\n";
         $argumentsCountCheckString .= "        return;\n";
         $argumentsCountCheckString .= "    }\n";
     }
     return $argumentsCountCheckString;
 }
 
 sub GenerateParametersCheck
 {
     my $function = shift;
     my $interface = shift;
     my $forMainWorldSuffix = shift;
     my $style = shift || "new";
 
     my $parameterCheckString = "";
     my $paramIndex = 0;
     my %replacements = ();
 
     foreach my $parameter (@{$function->parameters}) {
         my $nativeType = GetNativeType($parameter->type, $parameter->extendedAttributes, "parameter");
 
         # Optional arguments without [Default=...] should generate an early call with fewer arguments.
         # Optional arguments with [Optional=...] should not generate the early call.
         # Optional Dictionary arguments always considered to have default of empty dictionary.
         if ($parameter->isOptional && !$parameter->extendedAttributes->{"Default"} && $nativeType ne "Dictionary" && !IsCallbackInterface($parameter->type)) {
-            $parameterCheckString .= "    if (args.Length() <= $paramIndex)";
+            $parameterCheckString .= "    if (UNLIKELY(args.Length() <= $paramIndex))";
             my $functionCall = GenerateFunctionCallString($function, $paramIndex, "    " x 2, $interface, $forMainWorldSuffix, %replacements);
             my $multiLine = ($functionCall =~ tr/\n//) > 1;
             $parameterCheckString .= $multiLine ? " {\n" : "\n";
             $parameterCheckString .= $functionCall;
             $parameterCheckString .= $multiLine ? "    }\n" : "\n";
         }
 
         my $parameterName = $parameter->name;
         AddToImplIncludes("bindings/v8/ExceptionState.h");
         if (IsCallbackInterface($parameter->type)) {
@@ skipping 119 matching lines @@
     foreach my $constructor (@{$interface->constructors}) {
         my $name = "constructor" . $constructor->overloadedIndex;
         my ($numMandatoryParams, $parametersCheck) = GenerateFunctionParametersCheck($constructor);
         $leastNumMandatoryParams = $numMandatoryParams if ($numMandatoryParams < $leastNumMandatoryParams);
         $code .= "    if ($parametersCheck) {\n";
         $code .= "        ${implClassName}V8Internal::${name}(args);\n";
         $code .= "        return;\n";
         $code .= "    }\n";
     }
     if ($leastNumMandatoryParams >= 1) {
-        $code .= "    if (args.Length() < $leastNumMandatoryParams) {\n";
+        $code .= "    if (UNLIKELY(args.Length() < $leastNumMandatoryParams)) {\n";
         $code .= "        throwNotEnoughArgumentsError(args.GetIsolate());\n";
         $code .= "        return;\n";
         $code .= "    }\n";
     }
     $code .= <<END;
     throwTypeError(args.GetIsolate());
     return;
 END
     $code .= "}\n\n";
     $implementation{nameSpaceInternal}->add($code);
@@ skipping 3492 matching lines @@
         if ($currentInterface->extendedAttributes->{$extendedAttribute}) {
             $found = 1;
         }
         return 1 if $found;
     }, 0);
 
     return $found;
 }
 
 1;