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-rw-r--r--js/src/regexp/regexp-macro-assembler.cc367
1 files changed, 367 insertions, 0 deletions
diff --git a/js/src/regexp/regexp-macro-assembler.cc b/js/src/regexp/regexp-macro-assembler.cc
new file mode 100644
index 0000000000..4a8dcd3ce8
--- /dev/null
+++ b/js/src/regexp/regexp-macro-assembler.cc
@@ -0,0 +1,367 @@
+// Copyright 2012 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "regexp/regexp-macro-assembler.h"
+
+#include "regexp/regexp-stack.h"
+
+#ifdef V8_INTL_SUPPORT
+#include "unicode/uchar.h"
+#include "unicode/unistr.h"
+#endif // V8_INTL_SUPPORT
+
+namespace v8 {
+namespace internal {
+
+RegExpMacroAssembler::RegExpMacroAssembler(Isolate* isolate, Zone* zone)
+ : slow_safe_compiler_(false),
+ global_mode_(NOT_GLOBAL),
+ isolate_(isolate),
+ zone_(zone) {}
+
+RegExpMacroAssembler::~RegExpMacroAssembler() = default;
+
+int RegExpMacroAssembler::CaseInsensitiveCompareUC16(Address byte_offset1,
+ Address byte_offset2,
+ size_t byte_length,
+ Isolate* isolate) {
+ // 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.
+ DCHECK_EQ(0, byte_length % 2);
+
+#ifdef V8_INTL_SUPPORT
+ int32_t length = (int32_t)(byte_length >> 1);
+ icu::UnicodeString uni_str_1(reinterpret_cast<const char16_t*>(byte_offset1),
+ length);
+ return uni_str_1.caseCompare(reinterpret_cast<const char16_t*>(byte_offset2),
+ length, U_FOLD_CASE_DEFAULT) == 0;
+#else
+ uc16* substring1 = reinterpret_cast<uc16*>(byte_offset1);
+ uc16* substring2 = reinterpret_cast<uc16*>(byte_offset2);
+ size_t length = byte_length >> 1;
+ DCHECK_NOT_NULL(isolate);
+ unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize =
+ isolate->regexp_macro_assembler_canonicalize();
+ 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;
+#endif // V8_INTL_SUPPORT
+}
+
+
+void RegExpMacroAssembler::CheckNotInSurrogatePair(int cp_offset,
+ Label* on_failure) {
+ Label ok;
+ // Check that current character is not a trail surrogate.
+ LoadCurrentCharacter(cp_offset, &ok);
+ CheckCharacterNotInRange(kTrailSurrogateStart, kTrailSurrogateEnd, &ok);
+ // Check that previous character is not a lead surrogate.
+ LoadCurrentCharacter(cp_offset - 1, &ok);
+ CheckCharacterInRange(kLeadSurrogateStart, kLeadSurrogateEnd, on_failure);
+ Bind(&ok);
+}
+
+void RegExpMacroAssembler::CheckPosition(int cp_offset,
+ Label* on_outside_input) {
+ LoadCurrentCharacter(cp_offset, on_outside_input, true);
+}
+
+void RegExpMacroAssembler::LoadCurrentCharacter(int cp_offset,
+ Label* on_end_of_input,
+ bool check_bounds,
+ int characters,
+ int eats_at_least) {
+ // By default, eats_at_least = characters.
+ if (eats_at_least == kUseCharactersValue) {
+ eats_at_least = characters;
+ }
+
+ LoadCurrentCharacterImpl(cp_offset, on_end_of_input, check_bounds, characters,
+ eats_at_least);
+}
+
+bool RegExpMacroAssembler::CheckSpecialCharacterClass(uc16 type,
+ Label* on_no_match) {
+ return false;
+}
+
+NativeRegExpMacroAssembler::NativeRegExpMacroAssembler(Isolate* isolate,
+ Zone* zone)
+ : RegExpMacroAssembler(isolate, zone) {}
+
+NativeRegExpMacroAssembler::~NativeRegExpMacroAssembler() = default;
+
+bool NativeRegExpMacroAssembler::CanReadUnaligned() {
+ return FLAG_enable_regexp_unaligned_accesses && !slow_safe();
+}
+
+const byte* NativeRegExpMacroAssembler::StringCharacterPosition(
+ String subject, int start_index, const DisallowHeapAllocation& no_gc) {
+ if (subject.IsConsString()) {
+ subject = ConsString::cast(subject).first();
+ } else if (subject.IsSlicedString()) {
+ start_index += SlicedString::cast(subject).offset();
+ subject = SlicedString::cast(subject).parent();
+ }
+ if (subject.IsThinString()) {
+ subject = ThinString::cast(subject).actual();
+ }
+ DCHECK_LE(0, start_index);
+ DCHECK_LE(start_index, subject.length());
+ if (subject.IsSeqOneByteString()) {
+ return reinterpret_cast<const byte*>(
+ SeqOneByteString::cast(subject).GetChars(no_gc) + start_index);
+ } else if (subject.IsSeqTwoByteString()) {
+ return reinterpret_cast<const byte*>(
+ SeqTwoByteString::cast(subject).GetChars(no_gc) + start_index);
+ } else if (subject.IsExternalOneByteString()) {
+ return reinterpret_cast<const byte*>(
+ ExternalOneByteString::cast(subject).GetChars() + start_index);
+ } else {
+ DCHECK(subject.IsExternalTwoByteString());
+ return reinterpret_cast<const byte*>(
+ ExternalTwoByteString::cast(subject).GetChars() + start_index);
+ }
+}
+
+// This method may only be called after an interrupt.
+int NativeRegExpMacroAssembler::CheckStackGuardState(
+ Isolate* isolate, int start_index, RegExp::CallOrigin call_origin,
+ Address* return_address, Code re_code, Address* subject,
+ const byte** input_start, const byte** input_end) {
+ DisallowHeapAllocation no_gc;
+
+ DCHECK(re_code.raw_instruction_start() <= *return_address);
+ DCHECK(*return_address <= re_code.raw_instruction_end());
+ StackLimitCheck check(isolate);
+ bool js_has_overflowed = check.JsHasOverflowed();
+
+ if (call_origin == RegExp::CallOrigin::kFromJs) {
+ // Direct calls from JavaScript can be interrupted in two ways:
+ // 1. A real stack overflow, in which case we let the caller throw the
+ // exception.
+ // 2. The stack guard was used to interrupt execution for another purpose,
+ // forcing the call through the runtime system.
+
+ // Bug(v8:9540) Investigate why this method is called from JS although no
+ // stackoverflow or interrupt is pending on ARM64. We return 0 in this case
+ // to continue execution normally.
+ if (js_has_overflowed) {
+ return EXCEPTION;
+ } else if (check.InterruptRequested()) {
+ return RETRY;
+ } else {
+ return 0;
+ }
+ }
+ DCHECK(call_origin == RegExp::CallOrigin::kFromRuntime);
+
+ // Prepare for possible GC.
+ HandleScope handles(isolate);
+ Handle<Code> code_handle(re_code, isolate);
+ Handle<String> subject_handle(String::cast(Object(*subject)), isolate);
+ bool is_one_byte = String::IsOneByteRepresentationUnderneath(*subject_handle);
+ int return_value = 0;
+
+ if (js_has_overflowed) {
+ AllowHeapAllocation yes_gc;
+ isolate->StackOverflow();
+ return_value = EXCEPTION;
+ } else if (check.InterruptRequested()) {
+ AllowHeapAllocation yes_gc;
+ Object result = isolate->stack_guard()->HandleInterrupts();
+ if (result.IsException(isolate)) return_value = EXCEPTION;
+ }
+
+ if (*code_handle != re_code) { // Return address no longer valid
+ intptr_t delta = code_handle->address() - re_code.address();
+ // Overwrite the return address on the stack.
+ *return_address += delta;
+ }
+
+ // If we continue, we need to update the subject string addresses.
+ if (return_value == 0) {
+ // String encoding might have changed.
+ if (String::IsOneByteRepresentationUnderneath(*subject_handle) !=
+ is_one_byte) {
+ // If we changed between an LATIN1 and an UC16 string, the specialized
+ // code cannot be used, and we need to restart regexp matching from
+ // scratch (including, potentially, compiling a new version of the code).
+ return_value = RETRY;
+ } else {
+ *subject = subject_handle->ptr();
+ intptr_t byte_length = *input_end - *input_start;
+ *input_start =
+ StringCharacterPosition(*subject_handle, start_index, no_gc);
+ *input_end = *input_start + byte_length;
+ }
+ }
+ return return_value;
+}
+
+// Returns a {Result} sentinel, or the number of successful matches.
+int NativeRegExpMacroAssembler::Match(Handle<JSRegExp> regexp,
+ Handle<String> subject,
+ int* offsets_vector,
+ int offsets_vector_length,
+ int previous_index, Isolate* isolate) {
+ DCHECK(subject->IsFlat());
+ DCHECK_LE(0, previous_index);
+ DCHECK_LE(previous_index, subject->length());
+
+ // No allocations before calling the regexp, but we can't use
+ // DisallowHeapAllocation, 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()) {
+ DCHECK_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();
+ }
+ if (StringShape(subject_ptr).IsThin()) {
+ subject_ptr = ThinString::cast(subject_ptr).actual();
+ }
+ // Ensure that an underlying string has the same representation.
+ bool is_one_byte = subject_ptr.IsOneByteRepresentation();
+ DCHECK(subject_ptr.IsExternalString() || subject_ptr.IsSeqString());
+ // String is now either Sequential or External
+ int char_size_shift = is_one_byte ? 0 : 1;
+
+ DisallowHeapAllocation no_gc;
+ const byte* input_start =
+ StringCharacterPosition(subject_ptr, start_offset + slice_offset, no_gc);
+ int byte_length = char_length << char_size_shift;
+ const byte* input_end = input_start + byte_length;
+ return Execute(*subject, start_offset, input_start, input_end, offsets_vector,
+ offsets_vector_length, isolate, *regexp);
+}
+
+// Returns a {Result} sentinel, or the number of successful matches.
+// TODO(pthier): The JSRegExp object is passed to native irregexp code to match
+// the signature of the interpreter. We should get rid of JS objects passed to
+// internal methods.
+int NativeRegExpMacroAssembler::Execute(
+ String input, // This needs to be the unpacked (sliced, cons) string.
+ int start_offset, const byte* input_start, const byte* input_end,
+ int* output, int output_size, Isolate* isolate, JSRegExp regexp) {
+ // Ensure that the minimum stack has been allocated.
+ RegExpStackScope stack_scope(isolate);
+ Address stack_base = stack_scope.stack()->stack_base();
+
+ bool is_one_byte = String::IsOneByteRepresentationUnderneath(input);
+ Code code = Code::cast(regexp.Code(is_one_byte));
+ RegExp::CallOrigin call_origin = RegExp::CallOrigin::kFromRuntime;
+
+ using RegexpMatcherSig = int(
+ Address input_string, int start_offset, // NOLINT(readability/casting)
+ const byte* input_start, const byte* input_end, int* output,
+ int output_size, Address stack_base, int call_origin, Isolate* isolate,
+ Address regexp);
+
+ auto fn = GeneratedCode<RegexpMatcherSig>::FromCode(code);
+ int result =
+ fn.Call(input.ptr(), start_offset, input_start, input_end, output,
+ output_size, stack_base, call_origin, isolate, regexp.ptr());
+ DCHECK(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. Additionally, we allow heap
+ // allocation because even though it invalidates {input_start} and
+ // {input_end}, we are about to return anyway.
+ AllowHeapAllocation allow_allocation;
+ isolate->StackOverflow();
+ }
+ return result;
+}
+
+// clang-format off
+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'
+ // Latin-1 range
+ 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,
+ 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,
+
+ 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,
+};
+// clang-format on
+
+Address NativeRegExpMacroAssembler::GrowStack(Address stack_pointer,
+ Address* stack_base,
+ Isolate* isolate) {
+ RegExpStack* regexp_stack = isolate->regexp_stack();
+ size_t size = regexp_stack->stack_capacity();
+ Address old_stack_base = regexp_stack->stack_base();
+ DCHECK(old_stack_base == *stack_base);
+ DCHECK(stack_pointer <= old_stack_base);
+ DCHECK(static_cast<size_t>(old_stack_base - stack_pointer) <= size);
+ Address new_stack_base = regexp_stack->EnsureCapacity(size * 2);
+ if (new_stack_base == kNullAddress) {
+ return kNullAddress;
+ }
+ *stack_base = new_stack_base;
+ intptr_t stack_content_size = old_stack_base - stack_pointer;
+ return new_stack_base - stack_content_size;
+}
+
+} // namespace internal
+} // namespace v8
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