Add bytecodes and an interpreter for executing regular expressions. Very...

src/assembler-re2k.cc

Index: src/assembler-re2k.cc
===================================================================
--- src/assembler-re2k.cc	(revision 0)
+++ src/assembler-re2k.cc	(revision 0)
@@ -0,0 +1,258 @@
+// 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.
+
+// A light-weight assembler for the Regexp2000 byte code.
+
+
+#include "v8.h"
+#include "ast.h"
+#include "bytecodes-re2k.h"
+#include "regexp-codegen.h"
+#include "assembler-re2k.h"
+
+#include "assembler-re2k-inl.h"
+
+
+namespace v8 { namespace internal {
+
+
+static inline int Load32(const byte* pc) {
+#ifdef CAN_READ_UNALIGNED
+  return *reinterpret_cast<const int*>(pc);
+#else
+  union {
+    int word;
+    byte bytes[4];
+  } u;
+  u.bytes[0] = pc[0];
+  u.bytes[1] = pc[1];
+  u.bytes[2] = pc[2];
+  u.bytes[3] = pc[3];
+  return u.word;
+#endif
+}
+
+
+Re2kAssembler::Re2kAssembler(byte* buffer, int buffer_size)
+  : buffer_(buffer),
+    buffer_size_(buffer_size),
+    limit_(buffer + buffer_size - 3),
+    pc_(buffer),
+    own_buffer_(false) {
+}
+
+
+Re2kAssembler::~Re2kAssembler() {
+}
+
+
+void Re2kAssembler::PushCurrentPosition(int cp_offset) {
+  ASSERT(cp_offset >= 0);
+  if (cp_offset < 256) {
+    Emit(BC_PUSH_CP);
+    Emit(cp_offset);
+  } else {
+    Emit(BC_PUSH_CP_WIDE);
+    Emit32(cp_offset);
+  }
+}
+
+
+void Re2kAssembler::PushBacktrack(Label* l) {
+  Emit(BC_PUSH_BT);
+  EmitOrLink(l);
+}
+
+
+void Re2kAssembler::PushCapture(int index) {
+  ASSERT(index >= 0);
+  Emit(BC_PUSH_CAPTURE);
+  Emit(index);
+}
+
+
+void Re2kAssembler::SetCapture(int index, int cp_offset) {
+  ASSERT(cp_offset >= 0);
+  ASSERT(index >= 0);
+  if (cp_offset < 256) {
+    Emit(BC_SET_CAPTURE);
+    Emit(index);
+    Emit(cp_offset);
+  } else {
+    Emit(BC_SET_CAPTURE_WIDE);
+    Emit(index);
+    Emit32(cp_offset);
+  }
+}
+
+
+void Re2kAssembler::PopCurrentPosition() {
+  Emit(BC_POP_CP);
+}
+
+
+void Re2kAssembler::PopBacktrack() {
+  Emit(BC_POP_BT);
+}
+
+
+void Re2kAssembler::PopCapture(int index) {
+  Emit(BC_POP_CAPTURE);
+  Emit(index);
+}
+
+
+void Re2kAssembler::Fail() {
+  Emit(BC_FAIL);
+}
+
+
+void Re2kAssembler::FailIfWithin(int distance_from_end) {
+  if (distance_from_end < 256) {
+    Emit(BC_FAIL_IF_WITHIN);
+    Emit(distance_from_end);
+  } else {
+    Emit(BC_FAIL_IF_WITHIN_WIDE);
+    Emit32(distance_from_end);
+  }
+}
+
+
+void Re2kAssembler::Succeed() {
+  Emit(BC_SUCCEED);
+}
+
+
+void Re2kAssembler::Bind(Label* l) {
+  int bind_to = pc_ - buffer_;
+  ASSERT(!l->is_bound());
+  if (l->is_linked()) {
+    int pos = l->pos();
+    while (pos != 0) {
+      int fixup = pos;
+      pos = Load32(buffer_ + fixup);
+      Store32(bind_to, buffer_ + fixup);
+    }
+  }
+  l->bind_to(bind_to);
+}
+
+
+void Re2kAssembler::AdvanceCP(int cp_offset) {
+  if (cp_offset < 256) {
+    Emit(BC_ADVANCE_CP);
+    Emit(cp_offset);
+  } else {
+    Emit(BC_ADVANCE_CP_WIDE);
+    Emit32(cp_offset);
+  }
+}
+
+
+void Re2kAssembler::GoTo(Label* l) {
+  Emit(BC_GOTO);
+  EmitOrLink(l);
+}
+
+
+void Re2kAssembler::LoadCurrentChar(int cp_offset) {
+  if (cp_offset < 256) {
+    Emit(BC_LOAD_CURRENT_CHAR);
+    Emit(cp_offset);
+  } else {
+    Emit(BC_LOAD_CURRENT_CHAR_WIDE);
+    Emit32(cp_offset);
+  }
+}
+
+
+void Re2kAssembler::CheckChar(uc16 c, Label* on_mismatch) {
+  Emit(BC_CHECK_CHAR);
+  Emit16(c);
+  EmitOrLink(on_mismatch);
+}
+
+
+void Re2kAssembler::CheckNotChar(uc16 c, Label* on_match) {
+  Emit(BC_CHECK_NOT_CHAR);
+  Emit16(c);
+  EmitOrLink(on_match);
+}
+
+
+void Re2kAssembler::CheckRange(uc16 start, uc16 end, Label* on_mismatch) {
+  Emit(BC_CHECK_RANGE);
+  Emit16(start);
+  Emit16(end);
+  EmitOrLink(on_mismatch);
+}
+
+
+void Re2kAssembler::CheckNotRange(uc16 start, uc16 end, Label* on_match) {
+  Emit(BC_CHECK_NOT_RANGE);
+  Emit16(start);
+  Emit16(end);
+  EmitOrLink(on_match);
+}
+
+
+void Re2kAssembler::CheckBackref(int capture_index, Label* on_mismatch, int cp_offset) {
+  if (cp_offset < 256) {
+    Emit(BC_CHECK_BACKREF);
+    Emit(cp_offset);
+  } else {
+    Emit(BC_CHECK_BACKREF_WIDE);
+    Emit32(cp_offset);
+  }
+  Emit(capture_index);
+  EmitOrLink(on_mismatch);
+}
+
+
+void Re2kAssembler::CheckNotBackref(int capture_index, Label* on_match, int cp_offset) {
+  if (cp_offset < 256) {
+    Emit(BC_CHECK_NOT_BACKREF);
+    Emit(cp_offset);
+  } else {
+    Emit(BC_CHECK_NOT_BACKREF_WIDE);
+    Emit32(cp_offset);
+  }
+  Emit(capture_index);
+  EmitOrLink(on_match);
+}
+
+
+int Re2kAssembler::length() {
+  return pc_ - buffer_;
+}
+
+
+void Re2kAssembler::Copy(Address a) {
+  memcpy(a, buffer_, length());
+}
+
+} }  // namespace v8::internal