ES6: Array.prototype.slice and friends should use ToLength instead of ToUint32

src/macros.py

 # Copyright 2006-2009 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 129 matching lines @@
 define kBoundArgumentsStartIndex = 2;
 
 # Inline macros. Use %IS_VAR to make sure arg is evaluated only once.
 macro NUMBER_IS_NAN(arg) = (!%_IsSmi(%IS_VAR(arg)) && !(arg == arg));
 macro NUMBER_IS_FINITE(arg) = (%_IsSmi(%IS_VAR(arg)) || ((arg == arg) && (arg != 1/0) && (arg != -1/0)));
 macro TO_INTEGER(arg) = (%_IsSmi(%IS_VAR(arg)) ? arg : %NumberToInteger(ToNumber(arg)));
 macro TO_INTEGER_FOR_SIDE_EFFECT(arg) = (%_IsSmi(%IS_VAR(arg)) ? arg : ToNumber(arg));
 macro TO_INTEGER_MAP_MINUS_ZERO(arg) = (%_IsSmi(%IS_VAR(arg)) ? arg : %NumberToIntegerMapMinusZero(ToNumber(arg)));
 macro TO_INT32(arg) = (arg | 0);
 macro TO_UINT32(arg) = (arg >>> 0);
+macro TO_LENGTH(arg) = (harmony_tolength ? $toLength(arg) : TO_UINT32(arg));

[Camillo Bruni, 2015/09/09 13:51:16]

With the possibility of being annoying... maybe we could change the macro name
to reflect that it might change behavior depending on a flag. For instance
TO_LENGHT_OR_UINT32?

There has been some controversy among my colleagues on how to nicely implement
this change :)

[aperez, 2015/09/09 18:20:45]

Ack. I don't mind changing the name. Reviews with nits are fine as long as there
are progress and everybody is happy with the final version of the patch :)

 macro TO_STRING_INLINE(arg) = (IS_STRING(%IS_VAR(arg)) ? arg : $nonStringToString(arg));
 macro TO_NUMBER_INLINE(arg) = (IS_NUMBER(%IS_VAR(arg)) ? arg : $nonNumberToNumber(arg));
 macro TO_OBJECT(arg) = (%_ToObject(arg));
 macro TO_PRIMITIVE(arg) = (%_ToPrimitive(arg));
 macro TO_PRIMITIVE_NUMBER(arg) = (%_ToPrimitive_Number(arg));
 macro TO_PRIMITIVE_STRING(arg) = (%_ToPrimitive_String(arg));
 macro TO_NAME(arg) = (%_ToName(arg));
 macro JSON_NUMBER_TO_STRING(arg) = ((%_IsSmi(%IS_VAR(arg)) || arg - arg == 0) ? %_NumberToString(arg) : "null");
 macro HAS_OWN_PROPERTY(arg, index) = (%_CallFunction(arg, index, ObjectHasOwnProperty));
 macro HAS_INDEX(array, index, is_array) = ((is_array && %_HasFastPackedElements(%IS_VAR(array))) ? (index < array.length) : (index in array));
@@ skipping 141 matching lines @@
 define NOT_FOUND = -1;
 
 # Check whether debug is active.
 define DEBUG_IS_ACTIVE = (%_DebugIsActive() != 0);
 macro DEBUG_IS_STEPPING(function) = (%_DebugIsActive() != 0 && %DebugCallbackSupportsStepping(function));
 macro DEBUG_PREPARE_STEP_IN_IF_STEPPING(function) = if (DEBUG_IS_STEPPING(function)) %DebugPrepareStepInIfStepping(function);
 
 # SharedFlag equivalents
 define kNotShared = false;
 define kShared = true;