// Copyright 2012 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 // with the distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived // from this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. #include "elements-kind.h" #include "api.h" #include "elements.h" #include "objects.h" namespace v8 { namespace internal { const char* ElementsKindToString(ElementsKind kind) { ElementsAccessor* accessor = ElementsAccessor::ForKind(kind); return accessor->name(); } void PrintElementsKind(FILE* out, ElementsKind kind) { PrintF(out, "%s", ElementsKindToString(kind)); } ElementsKind GetInitialFastElementsKind() { if (FLAG_packed_arrays) { return FAST_SMI_ELEMENTS; } else { return FAST_HOLEY_SMI_ELEMENTS; } } struct InitializeFastElementsKindSequence { static void Construct( ElementsKind** fast_elements_kind_sequence_ptr) { ElementsKind* fast_elements_kind_sequence = new ElementsKind[kFastElementsKindCount]; *fast_elements_kind_sequence_ptr = fast_elements_kind_sequence; STATIC_ASSERT(FAST_SMI_ELEMENTS == FIRST_FAST_ELEMENTS_KIND); fast_elements_kind_sequence[0] = FAST_SMI_ELEMENTS; fast_elements_kind_sequence[1] = FAST_HOLEY_SMI_ELEMENTS; fast_elements_kind_sequence[2] = FAST_DOUBLE_ELEMENTS; fast_elements_kind_sequence[3] = FAST_HOLEY_DOUBLE_ELEMENTS; fast_elements_kind_sequence[4] = FAST_ELEMENTS; fast_elements_kind_sequence[5] = FAST_HOLEY_ELEMENTS; } }; static LazyInstance<ElementsKind*, InitializeFastElementsKindSequence>::type fast_elements_kind_sequence = LAZY_INSTANCE_INITIALIZER; ElementsKind GetFastElementsKindFromSequenceIndex(int sequence_number) { ASSERT(sequence_number >= 0 && sequence_number < kFastElementsKindCount); return fast_elements_kind_sequence.Get()[sequence_number]; } int GetSequenceIndexFromFastElementsKind(ElementsKind elements_kind) { for (int i = 0; i < kFastElementsKindCount; ++i) { if (fast_elements_kind_sequence.Get()[i] == elements_kind) { return i; } } UNREACHABLE(); return 0; } ElementsKind GetNextMoreGeneralFastElementsKind(ElementsKind elements_kind, bool allow_only_packed) { ASSERT(IsFastElementsKind(elements_kind)); ASSERT(elements_kind != TERMINAL_FAST_ELEMENTS_KIND); while (true) { int index = GetSequenceIndexFromFastElementsKind(elements_kind) + 1; elements_kind = GetFastElementsKindFromSequenceIndex(index); if (!IsFastHoleyElementsKind(elements_kind) || !allow_only_packed) { return elements_kind; } } UNREACHABLE(); return TERMINAL_FAST_ELEMENTS_KIND; } bool IsMoreGeneralElementsKindTransition(ElementsKind from_kind, ElementsKind to_kind) { switch (from_kind) { case FAST_SMI_ELEMENTS: return to_kind != FAST_SMI_ELEMENTS; case FAST_HOLEY_SMI_ELEMENTS: return to_kind != FAST_SMI_ELEMENTS && to_kind != FAST_HOLEY_SMI_ELEMENTS; case FAST_DOUBLE_ELEMENTS: return to_kind != FAST_SMI_ELEMENTS && to_kind != FAST_HOLEY_SMI_ELEMENTS && to_kind != FAST_DOUBLE_ELEMENTS; case FAST_HOLEY_DOUBLE_ELEMENTS: return to_kind == FAST_ELEMENTS || to_kind == FAST_HOLEY_ELEMENTS; case FAST_ELEMENTS: return to_kind == FAST_HOLEY_ELEMENTS; case FAST_HOLEY_ELEMENTS: return false; default: return false; } } } } // namespace v8::internal