// Copyright 2008 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 "v8.h"
#include "ast.h"
#include "assembler.h"
#include "regexp-stack.h"
#include "regexp-macro-assembler.h"
#include "simulator.h"
namespace v8 {
namespace internal {
RegExpMacroAssembler::RegExpMacroAssembler() : slow_safe_compiler_(false) {
}
RegExpMacroAssembler::~RegExpMacroAssembler() {
}
bool RegExpMacroAssembler::CanReadUnaligned() {
#ifdef V8_HOST_CAN_READ_UNALIGNED
return true;
#else
return false;
#endif
}
#ifndef V8_INTERPRETED_REGEXP // Avoid unused code, e.g., on ARM.
NativeRegExpMacroAssembler::NativeRegExpMacroAssembler()
: RegExpMacroAssembler() {
}
NativeRegExpMacroAssembler::~NativeRegExpMacroAssembler() {
}
bool NativeRegExpMacroAssembler::CanReadUnaligned() {
#ifdef V8_TARGET_CAN_READ_UNALIGNED
return !slow_safe();
#else
return false;
#endif
}
const byte* NativeRegExpMacroAssembler::StringCharacterPosition(
String* subject,
int start_index) {
// Not just flat, but ultra flat.
ASSERT(subject->IsExternalString() || subject->IsSeqString());
ASSERT(start_index >= 0);
ASSERT(start_index <= subject->length());
if (subject->IsAsciiRepresentation()) {
const byte* address;
if (StringShape(subject).IsExternal()) {
const char* data = ExternalAsciiString::cast(subject)->GetChars();
address = reinterpret_cast<const byte*>(data);
} else {
ASSERT(subject->IsSeqAsciiString());
char* data = SeqAsciiString::cast(subject)->GetChars();
address = reinterpret_cast<const byte*>(data);
}
return address + start_index;
}
const uc16* data;
if (StringShape(subject).IsExternal()) {
data = ExternalTwoByteString::cast(subject)->GetChars();
} else {
ASSERT(subject->IsSeqTwoByteString());
data = SeqTwoByteString::cast(subject)->GetChars();
}
return reinterpret_cast<const byte*>(data + start_index);
}
NativeRegExpMacroAssembler::Result NativeRegExpMacroAssembler::Match(
Handle<Code> regexp_code,
Handle<String> subject,
int* offsets_vector,
int offsets_vector_length,
int previous_index,
Isolate* isolate) {
ASSERT(subject->IsFlat());
ASSERT(previous_index >= 0);
ASSERT(previous_index <= subject->length());
// No allocations before calling the regexp, but we can't use
// AssertNoAllocation, since regexps might be preempted, and another thread
// might do allocation anyway.
String* subject_ptr = *subject;
// Character offsets into string.
int start_offset = previous_index;
int char_length = subject_ptr->length() - start_offset;
int slice_offset = 0;
// The string has been flattened, so if it is a cons string it contains the
// full string in the first part.
if (StringShape(subject_ptr).IsCons()) {
ASSERT_EQ(0, ConsString::cast(subject_ptr)->second()->length());
subject_ptr = ConsString::cast(subject_ptr)->first();
} else if (StringShape(subject_ptr).IsSliced()) {
SlicedString* slice = SlicedString::cast(subject_ptr);
subject_ptr = slice->parent();
slice_offset = slice->offset();
}
// Ensure that an underlying string has the same ASCII-ness.
bool is_ascii = subject_ptr->IsAsciiRepresentation();
ASSERT(subject_ptr->IsExternalString() || subject_ptr->IsSeqString());
// String is now either Sequential or External
int char_size_shift = is_ascii ? 0 : 1;
const byte* input_start =
StringCharacterPosition(subject_ptr, start_offset + slice_offset);
int byte_length = char_length << char_size_shift;
const byte* input_end = input_start + byte_length;
Result res = Execute(*regexp_code,
*subject,
start_offset,
input_start,
input_end,
offsets_vector,
isolate);
return res;
}
NativeRegExpMacroAssembler::Result NativeRegExpMacroAssembler::Execute(
Code* code,
String* input, // This needs to be the unpacked (sliced, cons) string.
int start_offset,
const byte* input_start,
const byte* input_end,
int* output,
Isolate* isolate) {
ASSERT(isolate == Isolate::Current());
// Ensure that the minimum stack has been allocated.
RegExpStackScope stack_scope(isolate);
Address stack_base = stack_scope.stack()->stack_base();
int direct_call = 0;
int result = CALL_GENERATED_REGEXP_CODE(code->entry(),
input,
start_offset,
input_start,
input_end,
output,
stack_base,
direct_call,
isolate);
ASSERT(result <= SUCCESS);
ASSERT(result >= RETRY);
if (result == EXCEPTION && !isolate->has_pending_exception()) {
// We detected a stack overflow (on the backtrack stack) in RegExp code,
// but haven't created the exception yet.
isolate->StackOverflow();
}
return static_cast<Result>(result);
}
const byte NativeRegExpMacroAssembler::word_character_map[] = {
0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u,
0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u,
0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u,
0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u,
0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u,
0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u,
0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, // '0' - '7'
0xffu, 0xffu, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, // '8' - '9'
0x00u, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, // 'A' - 'G'
0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, // 'H' - 'O'
0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, // 'P' - 'W'
0xffu, 0xffu, 0xffu, 0x00u, 0x00u, 0x00u, 0x00u, 0xffu, // 'X' - 'Z', '_'
0x00u, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, // 'a' - 'g'
0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, // 'h' - 'o'
0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, // 'p' - 'w'
0xffu, 0xffu, 0xffu, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, // 'x' - 'z'
};
int NativeRegExpMacroAssembler::CaseInsensitiveCompareUC16(
Address byte_offset1,
Address byte_offset2,
size_t byte_length,
Isolate* isolate) {
ASSERT(isolate == Isolate::Current());
unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize =
isolate->regexp_macro_assembler_canonicalize();
// This function is not allowed to cause a garbage collection.
// A GC might move the calling generated code and invalidate the
// return address on the stack.
ASSERT(byte_length % 2 == 0);
uc16* substring1 = reinterpret_cast<uc16*>(byte_offset1);
uc16* substring2 = reinterpret_cast<uc16*>(byte_offset2);
size_t length = byte_length >> 1;
for (size_t i = 0; i < length; i++) {
unibrow::uchar c1 = substring1[i];
unibrow::uchar c2 = substring2[i];
if (c1 != c2) {
unibrow::uchar s1[1] = { c1 };
canonicalize->get(c1, '\0', s1);
if (s1[0] != c2) {
unibrow::uchar s2[1] = { c2 };
canonicalize->get(c2, '\0', s2);
if (s1[0] != s2[0]) {
return 0;
}
}
}
}
return 1;
}
Address NativeRegExpMacroAssembler::GrowStack(Address stack_pointer,
Address* stack_base,
Isolate* isolate) {
ASSERT(isolate == Isolate::Current());
RegExpStack* regexp_stack = isolate->regexp_stack();
size_t size = regexp_stack->stack_capacity();
Address old_stack_base = regexp_stack->stack_base();
ASSERT(old_stack_base == *stack_base);
ASSERT(stack_pointer <= old_stack_base);
ASSERT(static_cast<size_t>(old_stack_base - stack_pointer) <= size);
Address new_stack_base = regexp_stack->EnsureCapacity(size * 2);
if (new_stack_base == NULL) {
return NULL;
}
*stack_base = new_stack_base;
intptr_t stack_content_size = old_stack_base - stack_pointer;
return new_stack_base - stack_content_size;
}
#endif // V8_INTERPRETED_REGEXP
} } // namespace v8::internal