Eliminate the code that handles fallback to JSCRE. The only way to get

JSCRE now is to use the --noirregexp flag.  Also add code to check that
we react sensibly to some very large regexps.
Review URL: http://codereview.chromium.org/18587

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1166 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/flag-definitions.h

@@ -203,7 +203,6 @@ DEFINE_bool(preemption, false,
 DEFINE_bool(irregexp, true, "new regular expression code")
 DEFINE_bool(trace_regexps, false, "trace Irregexp execution")
 DEFINE_bool(irregexp_native, true, "use native code Irregexp implementation (IA32 only)")
-DEFINE_bool(disable_jscre, true, "abort if JSCRE is used.  Only useful with --irregexp")
 
 // Testing flags test/cctest/test-{flags,api,serialization}.cc
 DEFINE_bool(testing_bool_flag, true, "testing_bool_flag")

src/jsregexp.cc

@@ -298,21 +298,10 @@ Handle<Object> RegExpImpl::Exec(Handle<JSRegExp> regexp,
       return AtomExec(regexp, subject, index);
     case JSRegExp::IRREGEXP: {
       Handle<Object> result = IrregexpExec(regexp, subject, index);
-      if (!result.is_null() || Top::has_pending_exception()) {
+      if (result.is_null()) ASSERT(Top::has_pending_exception());
       return result;
     }
-      // We couldn't handle the regexp using Irregexp, so fall back
-      // on JSCRE.
-      // Reset the JSRegExp to use JSCRE.
-      JscrePrepare(regexp,
-                   Handle<String>(regexp->Pattern()),
-                   regexp->GetFlags());
-      // Fall-through to JSCRE.
-    }
     case JSRegExp::JSCRE:
-      if (FLAG_disable_jscre) {
-        UNIMPLEMENTED();
-      }
       return JscreExec(regexp, subject, index);
     default:
       UNREACHABLE();
@@ -328,22 +317,10 @@ Handle<Object> RegExpImpl::ExecGlobal(Handle<JSRegExp> regexp,
       return AtomExecGlobal(regexp, subject);
     case JSRegExp::IRREGEXP: {
       Handle<Object> result = IrregexpExecGlobal(regexp, subject);
-      if (!result.is_null() || Top::has_pending_exception()) {
+      if (result.is_null()) ASSERT(Top::has_pending_exception());
       return result;
     }
-      // Empty handle as result but no exception thrown means that
-      // the regexp contains features not yet handled by the irregexp
-      // compiler.
-      // We have to fall back on JSCRE. Reset the JSRegExp to use JSCRE.
-      JscrePrepare(regexp,
-                   Handle<String>(regexp->Pattern()),
-                   regexp->GetFlags());
-      // Fall-through to JSCRE.
-    }
     case JSRegExp::JSCRE:
-      if (FLAG_disable_jscre) {
-        UNIMPLEMENTED();
-      }
       return JscreExecGlobal(regexp, subject);
     default:
       UNREACHABLE();
@@ -1198,7 +1175,13 @@ class RegExpCompiler {
  public:
   RegExpCompiler(int capture_count, bool ignore_case, bool is_ascii);
 
-  int AllocateRegister() { return next_register_++; }
+  int AllocateRegister() {
+    if (next_register_ >= RegExpMacroAssembler::kMaxRegister) {
+      reg_exp_too_big_ = true;
+      return next_register_;
+    }
+    return next_register_++;
+  }
 
   Handle<FixedArray> Assemble(RegExpMacroAssembler* assembler,
                               RegExpNode* start,
@@ -1219,6 +1202,8 @@ class RegExpCompiler {
   inline void IncrementRecursionDepth() { recursion_depth_++; }
   inline void DecrementRecursionDepth() { recursion_depth_--; }
 
+  void SetRegExpTooBig() { reg_exp_too_big_ = true; }
+
   inline bool ignore_case() { return ignore_case_; }
   inline bool ascii() { return ascii_; }
 
@@ -1231,6 +1216,7 @@ class RegExpCompiler {
   RegExpMacroAssembler* macro_assembler_;
   bool ignore_case_;
   bool ascii_;
+  bool reg_exp_too_big_;
 };
 
 
@@ -1245,6 +1231,18 @@ class RecursionCheck {
 };
 
 
+static Handle<FixedArray> IrregexpRegExpTooBig(Handle<String> pattern) {
+  Handle<JSArray> array = Factory::NewJSArray(2);
+  SetElement(array, 0, pattern);
+  const char* message = "RegExp too big";
+  SetElement(array, 1, Factory::NewStringFromUtf8(CStrVector(message)));
+  Handle<Object> regexp_err =
+      Factory::NewSyntaxError("malformed_regexp", array);
+  Top::Throw(*regexp_err);
+  return Handle<FixedArray>();
+}
+
+
 // Attempts to compile the regexp using an Irregexp code generator.  Returns
 // a fixed array or a null handle depending on whether it succeeded.
 RegExpCompiler::RegExpCompiler(int capture_count, bool ignore_case, bool ascii)
@@ -1252,8 +1250,10 @@ RegExpCompiler::RegExpCompiler(int capture_count, bool ignore_case, bool ascii)
       work_list_(NULL),
       recursion_depth_(0),
       ignore_case_(ignore_case),
-      ascii_(ascii) {
+      ascii_(ascii),
+      reg_exp_too_big_(false) {
   accept_ = new EndNode(EndNode::ACCEPT);
+  ASSERT(next_register_ - 1 <= RegExpMacroAssembler::kMaxRegister);
 }
 
 
@@ -1273,17 +1273,13 @@ Handle<FixedArray> RegExpCompiler::Assemble(
   Label fail;
   macro_assembler->PushBacktrack(&fail);
   Trace new_trace;
-  if (!start->Emit(this, &new_trace)) {
-    fail.Unuse();
-    return Handle<FixedArray>::null();
-  }
+  start->Emit(this, &new_trace);
   macro_assembler_->Bind(&fail);
   macro_assembler_->Fail();
   while (!work_list.is_empty()) {
-    if (!work_list.RemoveLast()->Emit(this, &new_trace)) {
-      return Handle<FixedArray>::null();
-    }
+    work_list.RemoveLast()->Emit(this, &new_trace);
   }
+  if (reg_exp_too_big_) return IrregexpRegExpTooBig(pattern);
   Handle<FixedArray> array =
       Factory::NewFixedArray(RegExpImpl::kIrregexpDataLength);
   array->set(RegExpImpl::kIrregexpImplementationIndex,
@@ -1303,6 +1299,7 @@ Handle<FixedArray> RegExpCompiler::Assemble(
   return array;
 }
 
+
 bool Trace::DeferredAction::Mentions(int that) {
   if (type() == ActionNode::CLEAR_CAPTURES) {
     Interval range = static_cast<DeferredClearCaptures*>(this)->range();
@@ -1509,7 +1506,7 @@ void Trace::PerformDeferredActions(RegExpMacroAssembler* assembler,
 // This is called as we come into a loop choice node and some other tricky
 // nodes.  It normalizes the state of the code generator to ensure we can
 // generate generic code.
-bool Trace::Flush(RegExpCompiler* compiler, RegExpNode* successor) {
+void Trace::Flush(RegExpCompiler* compiler, RegExpNode* successor) {
   RegExpMacroAssembler* assembler = compiler->macro_assembler();
 
   ASSERT(actions_ != NULL ||
@@ -1526,7 +1523,8 @@ bool Trace::Flush(RegExpCompiler* compiler, RegExpNode* successor) {
     if (cp_offset_ != 0) assembler->AdvanceCurrentPosition(cp_offset_);
     // Create a new trivial state and generate the node with that.
     Trace new_state;
-    return successor->Emit(compiler, &new_state);
+    successor->Emit(compiler, &new_state);
+    return;
   }
 
   // Generate deferred actions here along with code to undo them again.
@@ -1554,11 +1552,10 @@ bool Trace::Flush(RegExpCompiler* compiler, RegExpNode* successor) {
   Label undo;
   assembler->PushBacktrack(&undo);
   Trace new_state;
-  bool ok = successor->Emit(compiler, &new_state);
+  successor->Emit(compiler, &new_state);
 
   // On backtrack we need to restore state.
   assembler->Bind(&undo);
-  if (!ok) return false;
   if (backtrack() != NULL) {
     assembler->PopCurrentPosition();
   }
@@ -1571,12 +1568,10 @@ bool Trace::Flush(RegExpCompiler* compiler, RegExpNode* successor) {
   } else {
     assembler->GoTo(backtrack());
   }
-
-  return true;
 }
 
 
-bool NegativeSubmatchSuccess::Emit(RegExpCompiler* compiler, Trace* trace) {
+void NegativeSubmatchSuccess::Emit(RegExpCompiler* compiler, Trace* trace) {
   RegExpMacroAssembler* assembler = compiler->macro_assembler();
 
   // Omit flushing the trace. We discard the entire stack frame anyway.
@@ -1600,13 +1595,13 @@ bool NegativeSubmatchSuccess::Emit(RegExpCompiler* compiler, Trace* trace) {
   // Now that we have unwound the stack we find at the top of the stack the
   // backtrack that the BeginSubmatch node got.
   assembler->Backtrack();
-  return true;
 }
 
 
-bool EndNode::Emit(RegExpCompiler* compiler, Trace* trace) {
+void EndNode::Emit(RegExpCompiler* compiler, Trace* trace) {
   if (!trace->is_trivial()) {
-    return trace->Flush(compiler, this);
+    trace->Flush(compiler, this);
+    return;
   }
   RegExpMacroAssembler* assembler = compiler->macro_assembler();
   if (!label()->is_bound()) {
@@ -1615,16 +1610,15 @@ bool EndNode::Emit(RegExpCompiler* compiler, Trace* trace) {
   switch (action_) {
     case ACCEPT:
       assembler->Succeed();
-      return true;
+      return;
     case BACKTRACK:
       assembler->GoTo(trace->backtrack());
-      return true;
+      return;
     case NEGATIVE_SUBMATCH_SUCCESS:
       // This case is handled in a different virtual method.
       UNREACHABLE();
   }
   UNIMPLEMENTED();
-  return false;
 }
 
 
@@ -2029,8 +2023,8 @@ RegExpNode::LimitResult RegExpNode::LimitVersions(RegExpCompiler* compiler,
   // If we get here code has been generated for this node too many times or
   // recursion is too deep.  Time to switch to a generic version.  The code for
   // generic versions above can handle deep recursion properly.
-  bool ok = trace->Flush(compiler, this);
-  return ok ? DONE : FAIL;
+  trace->Flush(compiler, this);
+  return DONE;
 }
 
 
@@ -2448,7 +2442,7 @@ static void EmitWordCheck(RegExpMacroAssembler* assembler,
 
 // Emit the code to check for a ^ in multiline mode (1-character lookbehind
 // that matches newline or the start of input).
-static bool EmitHat(RegExpCompiler* compiler,
+static void EmitHat(RegExpCompiler* compiler,
                     RegExpNode* on_success,
                     Trace* trace) {
   RegExpMacroAssembler* assembler = compiler->macro_assembler();
@@ -2475,12 +2469,12 @@ static bool EmitHat(RegExpCompiler* compiler,
   assembler->CheckCharacter('\n', &ok);
   assembler->CheckNotCharacter('\r', new_trace.backtrack());
   assembler->Bind(&ok);
-  return on_success->Emit(compiler, &new_trace);
+  on_success->Emit(compiler, &new_trace);
 }
 
 
 // Emit the code to handle \b and \B (word-boundary or non-word-boundary).
-static bool EmitBoundaryCheck(AssertionNode::AssertionNodeType type,
+static void EmitBoundaryCheck(AssertionNode::AssertionNodeType type,
                               RegExpCompiler* compiler,
                               RegExpNode* on_success,
                               Trace* trace) {
@@ -2542,11 +2536,11 @@ static bool EmitBoundaryCheck(AssertionNode::AssertionNodeType type,
 
   assembler->Bind(&ok);
 
-  return on_success->Emit(compiler, &new_trace);
+  on_success->Emit(compiler, &new_trace);
 }
 
 
-bool AssertionNode::Emit(RegExpCompiler* compiler, Trace* trace) {
+void AssertionNode::Emit(RegExpCompiler* compiler, Trace* trace) {
   RegExpMacroAssembler* assembler = compiler->macro_assembler();
   switch (type_) {
     case AT_END: {
@@ -2560,12 +2554,14 @@ bool AssertionNode::Emit(RegExpCompiler* compiler, Trace* trace) {
       assembler->CheckNotAtStart(trace->backtrack());
       break;
     case AFTER_NEWLINE:
-      return EmitHat(compiler, on_success(), trace);
+      EmitHat(compiler, on_success(), trace);
+      return;
     case AT_NON_BOUNDARY:
     case AT_BOUNDARY:
-      return EmitBoundaryCheck(type_, compiler, on_success(), trace);
+      EmitBoundaryCheck(type_, compiler, on_success(), trace);
+      return;
   }
-  return on_success()->Emit(compiler, trace);
+  on_success()->Emit(compiler, trace);
 }
 
 
@@ -2708,12 +2704,16 @@ int TextNode::Length() {
 // pass from left to right.  Instead we pass over the text node several times,
 // emitting code for some character positions every time.  See the comment on
 // TextEmitPass for details.
-bool TextNode::Emit(RegExpCompiler* compiler, Trace* trace) {
+void TextNode::Emit(RegExpCompiler* compiler, Trace* trace) {
   LimitResult limit_result = LimitVersions(compiler, trace);
-  if (limit_result == FAIL) return false;
-  if (limit_result == DONE) return true;
+  if (limit_result == DONE) return;
   ASSERT(limit_result == CONTINUE);
 
+  if (trace->cp_offset() + Length() > RegExpMacroAssembler::kMaxCPOffset) {
+    compiler->SetRegExpTooBig();
+    return;
+  }
+
   if (compiler->ascii()) {
     int dummy = 0;
     TextEmitPass(compiler, NON_ASCII_MATCH, false, trace, false, &dummy);
@@ -2771,9 +2771,9 @@ bool TextNode::Emit(RegExpCompiler* compiler, Trace* trace) {
                &bound_checked_to);
 
   Trace successor_trace(*trace);
-  successor_trace.AdvanceCurrentPositionInTrace(Length(), compiler->ascii());
+  successor_trace.AdvanceCurrentPositionInTrace(Length(), compiler);
   RecursionCheck rc(compiler);
-  return on_success()->Emit(compiler, &successor_trace);
+  on_success()->Emit(compiler, &successor_trace);
 }
 
 
@@ -2782,7 +2782,7 @@ void Trace::InvalidateCurrentCharacter() {
 }
 
 
-void Trace::AdvanceCurrentPositionInTrace(int by, bool ascii) {
+void Trace::AdvanceCurrentPositionInTrace(int by, RegExpCompiler* compiler) {
   ASSERT(by > 0);
   // We don't have an instruction for shifting the current character register
   // down or for using a shifted value for anything so lets just forget that
@@ -2791,8 +2791,12 @@ void Trace::AdvanceCurrentPositionInTrace(int by, bool ascii) {
   // Adjust the offsets of the quick check performed information.  This
   // information is used to find out what we already determined about the
   // characters by means of mask and compare.
-  quick_check_performed_.Advance(by, ascii);
+  quick_check_performed_.Advance(by, compiler->ascii());
   cp_offset_ += by;
+  if (cp_offset_ > RegExpMacroAssembler::kMaxCPOffset) {
+    compiler->SetRegExpTooBig();
+    cp_offset_ = 0;
+  }
   bound_checked_up_to_ = Max(0, bound_checked_up_to_ - by);
 }
 
@@ -2863,7 +2867,7 @@ void LoopChoiceNode::AddContinueAlternative(GuardedAlternative alt) {
 }
 
 
-bool LoopChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
+void LoopChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
   RegExpMacroAssembler* macro_assembler = compiler->macro_assembler();
   if (trace->stop_node() == this) {
     int text_length = GreedyLoopTextLength(&(alternatives_->at(0)));
@@ -2873,13 +2877,14 @@ bool LoopChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
     ASSERT(trace->cp_offset() == text_length);
     macro_assembler->AdvanceCurrentPosition(text_length);
     macro_assembler->GoTo(trace->loop_label());
-    return true;
+    return;
   }
   ASSERT(trace->stop_node() == NULL);
   if (!trace->is_trivial()) {
-    return trace->Flush(compiler, this);
+    trace->Flush(compiler, this);
+    return;
   }
-  return ChoiceNode::Emit(compiler, trace);
+  ChoiceNode::Emit(compiler, trace);
 }
 
 
@@ -3032,7 +3037,7 @@ class AlternativeGenerationList {
  */
 
 
-bool ChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
+void ChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
   RegExpMacroAssembler* macro_assembler = compiler->macro_assembler();
   int choice_count = alternatives_->length();
 #ifdef DEBUG
@@ -3047,8 +3052,7 @@ bool ChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
 #endif
 
   LimitResult limit_result = LimitVersions(compiler, trace);
-  if (limit_result == DONE) return true;
-  if (limit_result == FAIL) return false;
+  if (limit_result == DONE) return;
   ASSERT(limit_result == CONTINUE);
 
   RecursionCheck rc(compiler);
@@ -3079,13 +3083,8 @@ bool ChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
     macro_assembler->Bind(&loop_label);
     greedy_match_trace.set_stop_node(this);
     greedy_match_trace.set_loop_label(&loop_label);
-    bool ok = alternatives_->at(0).node()->Emit(compiler,
-                                                &greedy_match_trace);
+    alternatives_->at(0).node()->Emit(compiler, &greedy_match_trace);
     macro_assembler->Bind(&greedy_match_failed);
-    if (!ok) {
-      greedy_loop_label.Unuse();
-      return false;
-    }
   }
 
   Label second_choice;  // For use in greedy matches.
@@ -3157,10 +3156,7 @@ bool ChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
       for (int j = 0; j < guard_count; j++) {
         GenerateGuard(macro_assembler, guards->at(j), &new_trace);
       }
-      if (!alternative.node()->Emit(compiler, &new_trace)) {
-        greedy_loop_label.Unuse();
-        return false;
-      }
+      alternative.node()->Emit(compiler, &new_trace);
       preload_is_current = false;
     }
     macro_assembler->Bind(&alt_gen->after);
@@ -3178,26 +3174,23 @@ bool ChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
   // label was bound.
   for (int i = first_normal_choice; i < choice_count - 1; i++) {
     AlternativeGeneration* alt_gen = alt_gens.at(i);
-    if (!EmitOutOfLineContinuation(compiler,
+    EmitOutOfLineContinuation(compiler,
                               current_trace,
                               alternatives_->at(i),
                               alt_gen,
                               preload_characters,
-                                   alt_gens.at(i + 1)->expects_preload)) {
-      return false;
+                              alt_gens.at(i + 1)->expects_preload);
   }
-  }
-  return true;
 }
 
 
-bool ChoiceNode::EmitOutOfLineContinuation(RegExpCompiler* compiler,
+void ChoiceNode::EmitOutOfLineContinuation(RegExpCompiler* compiler,
                                            Trace* trace,
                                            GuardedAlternative alternative,
                                            AlternativeGeneration* alt_gen,
                                            int preload_characters,
                                            bool next_expects_preload) {
-  if (!alt_gen->possible_success.is_linked()) return true;
+  if (!alt_gen->possible_success.is_linked()) return;
 
   RegExpMacroAssembler* macro_assembler = compiler->macro_assembler();
   macro_assembler->Bind(&alt_gen->possible_success);
@@ -3212,7 +3205,7 @@ bool ChoiceNode::EmitOutOfLineContinuation(RegExpCompiler* compiler,
     for (int j = 0; j < guard_count; j++) {
       GenerateGuard(macro_assembler, guards->at(j), &out_of_line_trace);
     }
-    bool ok = alternative.node()->Emit(compiler, &out_of_line_trace);
+    alternative.node()->Emit(compiler, &out_of_line_trace);
     macro_assembler->Bind(&reload_current_char);
     // Reload the current character, since the next quick check expects that.
     // We don't need to check bounds here because we only get into this
@@ -3222,22 +3215,20 @@ bool ChoiceNode::EmitOutOfLineContinuation(RegExpCompiler* compiler,
                                           false,
                                           preload_characters);
     macro_assembler->GoTo(&(alt_gen->after));
-    return ok;
   } else {
     out_of_line_trace.set_backtrack(&(alt_gen->after));
     for (int j = 0; j < guard_count; j++) {
       GenerateGuard(macro_assembler, guards->at(j), &out_of_line_trace);
     }
-    return alternative.node()->Emit(compiler, &out_of_line_trace);
+    alternative.node()->Emit(compiler, &out_of_line_trace);
   }
 }
 
 
-bool ActionNode::Emit(RegExpCompiler* compiler, Trace* trace) {
+void ActionNode::Emit(RegExpCompiler* compiler, Trace* trace) {
   RegExpMacroAssembler* assembler = compiler->macro_assembler();
   LimitResult limit_result = LimitVersions(compiler, trace);
-  if (limit_result == DONE) return true;
-  if (limit_result == FAIL) return false;
+  if (limit_result == DONE) return;
   ASSERT(limit_result == CONTINUE);
 
   RecursionCheck rc(compiler);
@@ -3250,21 +3241,24 @@ bool ActionNode::Emit(RegExpCompiler* compiler, Trace* trace) {
                       trace);
       Trace new_trace = *trace;
       new_trace.add_action(&new_capture);
-      return on_success()->Emit(compiler, &new_trace);
+      on_success()->Emit(compiler, &new_trace);
+      break;
     }
     case INCREMENT_REGISTER: {
       Trace::DeferredIncrementRegister
           new_increment(data_.u_increment_register.reg);
       Trace new_trace = *trace;
       new_trace.add_action(&new_increment);
-      return on_success()->Emit(compiler, &new_trace);
+      on_success()->Emit(compiler, &new_trace);
+      break;
     }
     case SET_REGISTER: {
       Trace::DeferredSetRegister
           new_set(data_.u_store_register.reg, data_.u_store_register.value);
       Trace new_trace = *trace;
       new_trace.add_action(&new_set);
-      return on_success()->Emit(compiler, &new_trace);
+      on_success()->Emit(compiler, &new_trace);
+      break;
     }
     case CLEAR_CAPTURES: {
       Trace::DeferredClearCaptures
@@ -3272,15 +3266,20 @@ bool ActionNode::Emit(RegExpCompiler* compiler, Trace* trace) {
                              data_.u_clear_captures.range_to));
       Trace new_trace = *trace;
       new_trace.add_action(&new_capture);
-      return on_success()->Emit(compiler, &new_trace);
+      on_success()->Emit(compiler, &new_trace);
+      break;
     }
     case BEGIN_SUBMATCH:
-      if (!trace->is_trivial()) return trace->Flush(compiler, this);
+      if (!trace->is_trivial()) {
+        trace->Flush(compiler, this);
+      } else {
         assembler->WriteCurrentPositionToRegister(
             data_.u_submatch.current_position_register, 0);
         assembler->WriteStackPointerToRegister(
             data_.u_submatch.stack_pointer_register);
-      return on_success()->Emit(compiler, trace);
+        on_success()->Emit(compiler, trace);
+      }
+      break;
     case EMPTY_MATCH_CHECK: {
       int start_pos_reg = data_.u_empty_match_check.start_register;
       int stored_pos = 0;
@@ -3291,13 +3290,13 @@ bool ActionNode::Emit(RegExpCompiler* compiler, Trace* trace) {
         // If we know we haven't advanced and there is no minimum we
         // can just backtrack immediately.
         assembler->GoTo(trace->backtrack());
-        return true;
       } else if (know_dist && stored_pos < trace->cp_offset()) {
         // If we know we've advanced we can generate the continuation
         // immediately.
-        return on_success()->Emit(compiler, trace);
-      }
-      if (!trace->is_trivial()) return trace->Flush(compiler, this);
+        on_success()->Emit(compiler, trace);
+      } else if (!trace->is_trivial()) {
+        trace->Flush(compiler, this);
+      } else {
         Label skip_empty_check;
         // If we have a minimum number of repetitions we check the current
         // number first and skip the empty check if it's not enough.
@@ -3310,24 +3309,29 @@ bool ActionNode::Emit(RegExpCompiler* compiler, Trace* trace) {
         assembler->IfRegisterEqPos(data_.u_empty_match_check.start_register,
                                    trace->backtrack());
         assembler->Bind(&skip_empty_check);
-      return on_success()->Emit(compiler, trace);
+        on_success()->Emit(compiler, trace);
+      }
+      break;
     }
     case POSITIVE_SUBMATCH_SUCCESS: {
-      if (!trace->is_trivial()) return trace->Flush(compiler, this);
+      if (!trace->is_trivial()) {
+        trace->Flush(compiler, this);
+        return;
+      }
       assembler->ReadCurrentPositionFromRegister(
           data_.u_submatch.current_position_register);
       assembler->ReadStackPointerFromRegister(
           data_.u_submatch.stack_pointer_register);
       int clear_register_count = data_.u_submatch.clear_register_count;
       if (clear_register_count == 0) {
-        return on_success()->Emit(compiler, trace);
+        on_success()->Emit(compiler, trace);
+        return;
       }
       int clear_registers_from = data_.u_submatch.clear_register_from;
       Label clear_registers_backtrack;
       Trace new_trace = *trace;
       new_trace.set_backtrack(&clear_registers_backtrack);
-      bool ok = on_success()->Emit(compiler, &new_trace);
-      if (!ok) { return false; }
+      on_success()->Emit(compiler, &new_trace);
 
       assembler->Bind(&clear_registers_backtrack);
       int clear_registers_to = clear_registers_from + clear_register_count - 1;
@@ -3335,24 +3339,23 @@ bool ActionNode::Emit(RegExpCompiler* compiler, Trace* trace) {
 
       ASSERT(trace->backtrack() == NULL);
       assembler->Backtrack();
-      return true;
+      return;
     }
     default:
       UNREACHABLE();
-      return false;
   }
 }
 
 
-bool BackReferenceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
+void BackReferenceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
   RegExpMacroAssembler* assembler = compiler->macro_assembler();
   if (!trace->is_trivial()) {
-    return trace->Flush(compiler, this);
+    trace->Flush(compiler, this);
+    return;
   }
 
   LimitResult limit_result = LimitVersions(compiler, trace);
-  if (limit_result == DONE) return true;
-  if (limit_result == FAIL) return false;
+  if (limit_result == DONE) return;
   ASSERT(limit_result == CONTINUE);
 
   RecursionCheck rc(compiler);
@@ -3364,7 +3367,7 @@ bool BackReferenceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
   } else {
     assembler->CheckNotBackReference(start_reg_, trace->backtrack());
   }
-  return on_success()->Emit(compiler, trace);
+  on_success()->Emit(compiler, trace);
 }
 
 
@@ -4746,6 +4749,9 @@ Handle<FixedArray> RegExpEngine::Compile(RegExpCompileData* data,
                                          bool is_multiline,
                                          Handle<String> pattern,
                                          bool is_ascii) {
+  if ((data->capture_count + 1) * 2 - 1 > RegExpMacroAssembler::kMaxRegister) {
+    return IrregexpRegExpTooBig(pattern);
+  }
   RegExpCompiler compiler(data->capture_count, ignore_case, is_ascii);
   // Wrap the body of the regexp in capture #0.
   RegExpNode* captured_body = RegExpCapture::ToNode(data->tree,

src/jsregexp.h

@@ -588,9 +588,7 @@ class RegExpNode: public ZoneObject {
   virtual ~RegExpNode();
   virtual void Accept(NodeVisitor* visitor) = 0;
   // Generates a goto to this node or actually generates the code at this point.
-  // Until the implementation is complete we will return true for success and
-  // false for failure.
-  virtual bool Emit(RegExpCompiler* compiler, Trace* trace) = 0;
+  virtual void Emit(RegExpCompiler* compiler, Trace* trace) = 0;
   // How many characters must this node consume at a minimum in order to
   // succeed.  If we have found at least 'still_to_find' characters that
   // must be consumed there is no need to ask any following nodes whether
@@ -637,7 +635,7 @@ class RegExpNode: public ZoneObject {
   void set_siblings(SiblingList* other) { siblings_ = *other; }
 
  protected:
-  enum LimitResult { DONE, FAIL, CONTINUE };
+  enum LimitResult { DONE, CONTINUE };
   LimitResult LimitVersions(RegExpCompiler* compiler, Trace* trace);
 
   // Returns a sibling of this node whose interests and assumptions
@@ -738,7 +736,7 @@ class ActionNode: public SeqRegExpNode {
                                      int repetition_limit,
                                      RegExpNode* on_success);
   virtual void Accept(NodeVisitor* visitor);
-  virtual bool Emit(RegExpCompiler* compiler, Trace* trace);
+  virtual void Emit(RegExpCompiler* compiler, Trace* trace);
   virtual int EatsAtLeast(int still_to_find, int recursion_depth);
   virtual void GetQuickCheckDetails(QuickCheckDetails* details,
                                     RegExpCompiler* compiler,
@@ -800,7 +798,7 @@ class TextNode: public SeqRegExpNode {
     elms_->Add(TextElement::CharClass(that));
   }
   virtual void Accept(NodeVisitor* visitor);
-  virtual bool Emit(RegExpCompiler* compiler, Trace* trace);
+  virtual void Emit(RegExpCompiler* compiler, Trace* trace);
   virtual int EatsAtLeast(int still_to_find, int recursion_depth);
   virtual void GetQuickCheckDetails(QuickCheckDetails* details,
                                     RegExpCompiler* compiler,
@@ -858,7 +856,7 @@ class AssertionNode: public SeqRegExpNode {
     return new AssertionNode(AFTER_NEWLINE, on_success);
   }
   virtual void Accept(NodeVisitor* visitor);
-  virtual bool Emit(RegExpCompiler* compiler, Trace* trace);
+  virtual void Emit(RegExpCompiler* compiler, Trace* trace);
   virtual int EatsAtLeast(int still_to_find, int recursion_depth);
   virtual void GetQuickCheckDetails(QuickCheckDetails* details,
                                     RegExpCompiler* compiler,
@@ -885,7 +883,7 @@ class BackReferenceNode: public SeqRegExpNode {
   virtual void Accept(NodeVisitor* visitor);
   int start_register() { return start_reg_; }
   int end_register() { return end_reg_; }
-  virtual bool Emit(RegExpCompiler* compiler, Trace* trace);
+  virtual void Emit(RegExpCompiler* compiler, Trace* trace);
   virtual int EatsAtLeast(int still_to_find, int recursion_depth);
   virtual void GetQuickCheckDetails(QuickCheckDetails* details,
                                     RegExpCompiler* compiler,
@@ -905,7 +903,7 @@ class EndNode: public RegExpNode {
   enum Action { ACCEPT, BACKTRACK, NEGATIVE_SUBMATCH_SUCCESS };
   explicit EndNode(Action action) : action_(action) { }
   virtual void Accept(NodeVisitor* visitor);
-  virtual bool Emit(RegExpCompiler* compiler, Trace* trace);
+  virtual void Emit(RegExpCompiler* compiler, Trace* trace);
   virtual int EatsAtLeast(int still_to_find, int recursion_depth) { return 0; }
   virtual void GetQuickCheckDetails(QuickCheckDetails* details,
                                     RegExpCompiler* compiler,
@@ -931,7 +929,7 @@ class NegativeSubmatchSuccess: public EndNode {
         current_position_register_(position_reg),
         clear_capture_count_(clear_capture_count),
         clear_capture_start_(clear_capture_start) { }
-  virtual bool Emit(RegExpCompiler* compiler, Trace* trace);
+  virtual void Emit(RegExpCompiler* compiler, Trace* trace);
 
  private:
   int stack_pointer_register_;
@@ -986,7 +984,7 @@ class ChoiceNode: public RegExpNode {
   void AddAlternative(GuardedAlternative node) { alternatives()->Add(node); }
   ZoneList<GuardedAlternative>* alternatives() { return alternatives_; }
   DispatchTable* GetTable(bool ignore_case);
-  virtual bool Emit(RegExpCompiler* compiler, Trace* trace);
+  virtual void Emit(RegExpCompiler* compiler, Trace* trace);
   virtual int EatsAtLeast(int still_to_find, int recursion_depth);
   int EatsAtLeastHelper(int still_to_find,
                         int recursion_depth,
@@ -1011,7 +1009,7 @@ class ChoiceNode: public RegExpNode {
                      Guard *guard,
                      Trace* trace);
   int CalculatePreloadCharacters(RegExpCompiler* compiler);
-  bool EmitOutOfLineContinuation(RegExpCompiler* compiler,
+  void EmitOutOfLineContinuation(RegExpCompiler* compiler,
                                  Trace* trace,
                                  GuardedAlternative alternative,
                                  AlternativeGeneration* alt_gen,
@@ -1052,7 +1050,7 @@ class LoopChoiceNode: public ChoiceNode {
         body_can_be_zero_length_(body_can_be_zero_length) { }
   void AddLoopAlternative(GuardedAlternative alt);
   void AddContinueAlternative(GuardedAlternative alt);
-  virtual bool Emit(RegExpCompiler* compiler, Trace* trace);
+  virtual void Emit(RegExpCompiler* compiler, Trace* trace);
   virtual int EatsAtLeast(int still_to_find, int recursion_depth);
   virtual void GetQuickCheckDetails(QuickCheckDetails* details,
                                     RegExpCompiler* compiler,
@@ -1157,7 +1155,7 @@ class Trace {
   // and pushing a backtrack location onto the backtrack stack.  Once this is
   // done we can start a new trace or go to one that has already been
   // generated.
-  bool Flush(RegExpCompiler* compiler, RegExpNode* successor);
+  void Flush(RegExpCompiler* compiler, RegExpNode* successor);
   int cp_offset() { return cp_offset_; }
   DeferredAction* actions() { return actions_; }
   // A trivial trace is one that has no deferred actions or other state that
@@ -1205,7 +1203,7 @@ class Trace {
     quick_check_performed_ = *d;
   }
   void InvalidateCurrentCharacter();
-  void AdvanceCurrentPositionInTrace(int by, bool ascii);
+  void AdvanceCurrentPositionInTrace(int by, RegExpCompiler* compiler);
  private:
   int FindAffectedRegisters(OutSet* affected_registers);
   void PerformDeferredActions(RegExpMacroAssembler* macro,

src/regexp-macro-assembler-irregexp.cc

@@ -84,6 +84,8 @@ void RegExpMacroAssemblerIrregexp::EmitOrLink(Label* l) {
 
 
 void RegExpMacroAssemblerIrregexp::PopRegister(int register_index) {
+  ASSERT(register_index >= 0);
+  ASSERT(register_index <= kMaxRegister);
   Emit(BC_POP_REGISTER, register_index);
 }
 
@@ -92,6 +94,7 @@ void RegExpMacroAssemblerIrregexp::PushRegister(
     int register_index,
     StackCheckFlag check_stack_limit) {
   ASSERT(register_index >= 0);
+  ASSERT(register_index <= kMaxRegister);
   Emit(BC_PUSH_REGISTER, register_index);
 }
 
@@ -99,6 +102,7 @@ void RegExpMacroAssemblerIrregexp::PushRegister(
 void RegExpMacroAssemblerIrregexp::WriteCurrentPositionToRegister(
     int register_index, int cp_offset) {
   ASSERT(register_index >= 0);
+  ASSERT(register_index <= kMaxRegister);
   Emit(BC_SET_REGISTER_TO_CP, register_index);
   Emit32(cp_offset);  // Current position offset.
 }
@@ -115,6 +119,7 @@ void RegExpMacroAssemblerIrregexp::ClearRegisters(int reg_from, int reg_to) {
 void RegExpMacroAssemblerIrregexp::ReadCurrentPositionFromRegister(
     int register_index) {
   ASSERT(register_index >= 0);
+  ASSERT(register_index <= kMaxRegister);
   Emit(BC_SET_CP_TO_REGISTER, register_index);
 }
 
@@ -122,6 +127,7 @@ void RegExpMacroAssemblerIrregexp::ReadCurrentPositionFromRegister(
 void RegExpMacroAssemblerIrregexp::WriteStackPointerToRegister(
     int register_index) {
   ASSERT(register_index >= 0);
+  ASSERT(register_index <= kMaxRegister);
   Emit(BC_SET_REGISTER_TO_SP, register_index);
 }
 
@@ -129,12 +135,14 @@ void RegExpMacroAssemblerIrregexp::WriteStackPointerToRegister(
 void RegExpMacroAssemblerIrregexp::ReadStackPointerFromRegister(
     int register_index) {
   ASSERT(register_index >= 0);
+  ASSERT(register_index <= kMaxRegister);
   Emit(BC_SET_SP_TO_REGISTER, register_index);
 }
 
 
 void RegExpMacroAssemblerIrregexp::SetRegister(int register_index, int to) {
   ASSERT(register_index >= 0);
+  ASSERT(register_index <= kMaxRegister);
   Emit(BC_SET_REGISTER, register_index);
   Emit32(to);
 }
@@ -142,6 +150,7 @@ void RegExpMacroAssemblerIrregexp::SetRegister(int register_index, int to) {
 
 void RegExpMacroAssemblerIrregexp::AdvanceRegister(int register_index, int by) {
   ASSERT(register_index >= 0);
+  ASSERT(register_index <= kMaxRegister);
   Emit(BC_ADVANCE_REGISTER, register_index);
   Emit32(by);
 }
@@ -185,6 +194,8 @@ void RegExpMacroAssemblerIrregexp::Fail() {
 
 
 void RegExpMacroAssemblerIrregexp::AdvanceCurrentPosition(int by) {
+  ASSERT(by >= kMinCPOffset);
+  ASSERT(by <= kMaxCPOffset);
   Emit(BC_ADVANCE_CP, by);
 }
 
@@ -200,6 +211,8 @@ void RegExpMacroAssemblerIrregexp::LoadCurrentCharacter(int cp_offset,
                                                         Label* on_failure,
                                                         bool check_bounds,
                                                         int characters) {
+  ASSERT(cp_offset >= kMinCPOffset);
+  ASSERT(cp_offset <= kMaxCPOffset);
   int bytecode;
   if (check_bounds) {
     if (characters == 4) {
@@ -318,6 +331,8 @@ void RegExpMacroAssemblerIrregexp::CheckNotCharacterAfterMinusAnd(
 
 void RegExpMacroAssemblerIrregexp::CheckNotBackReference(int start_reg,
                                                          Label* on_not_equal) {
+  ASSERT(start_reg >= 0);
+  ASSERT(start_reg <= kMaxRegister);
   Emit(BC_CHECK_NOT_BACK_REF, start_reg);
   EmitOrLink(on_not_equal);
 }
@@ -326,6 +341,8 @@ void RegExpMacroAssemblerIrregexp::CheckNotBackReference(int start_reg,
 void RegExpMacroAssemblerIrregexp::CheckNotBackReferenceIgnoreCase(
     int start_reg,
     Label* on_not_equal) {
+  ASSERT(start_reg >= 0);
+  ASSERT(start_reg <= kMaxRegister);
   Emit(BC_CHECK_NOT_BACK_REF_NO_CASE, start_reg);
   EmitOrLink(on_not_equal);
 }
@@ -334,6 +351,8 @@ void RegExpMacroAssemblerIrregexp::CheckNotBackReferenceIgnoreCase(
 void RegExpMacroAssemblerIrregexp::CheckNotRegistersEqual(int reg1,
                                                           int reg2,
                                                           Label* on_not_equal) {
+  ASSERT(reg1 >= 0);
+  ASSERT(reg1 <= kMaxRegister);
   Emit(BC_CHECK_NOT_REGS_EQUAL, reg1);
   Emit32(reg2);
   EmitOrLink(on_not_equal);
@@ -376,6 +395,8 @@ void RegExpMacroAssemblerIrregexp::CheckCharacters(
   int cp_offset,
   Label* on_failure,
   bool check_end_of_string) {
+  ASSERT(cp_offset >= kMinCPOffset);
+  ASSERT(cp_offset + str.length() - 1 <= kMaxCPOffset);
   // It is vital that this loop is backwards due to the unchecked character
   // load below.
   for (int i = str.length() - 1; i >= 0; i--) {
@@ -394,7 +415,8 @@ void RegExpMacroAssemblerIrregexp::CheckCharacters(
 void RegExpMacroAssemblerIrregexp::IfRegisterLT(int register_index,
                                                 int comparand,
                                                 Label* on_less_than) {
-  ASSERT(comparand >= 0 && comparand <= 65535);
+  ASSERT(register_index >= 0);
+  ASSERT(register_index <= kMaxRegister);
   Emit(BC_CHECK_REGISTER_LT, register_index);
   Emit32(comparand);
   EmitOrLink(on_less_than);
@@ -404,7 +426,8 @@ void RegExpMacroAssemblerIrregexp::IfRegisterLT(int register_index,
 void RegExpMacroAssemblerIrregexp::IfRegisterGE(int register_index,
                                                 int comparand,
                                                 Label* on_greater_or_equal) {
-  ASSERT(comparand >= 0 && comparand <= 65535);
+  ASSERT(register_index >= 0);
+  ASSERT(register_index <= kMaxRegister);
   Emit(BC_CHECK_REGISTER_GE, register_index);
   Emit32(comparand);
   EmitOrLink(on_greater_or_equal);
@@ -413,6 +436,8 @@ void RegExpMacroAssemblerIrregexp::IfRegisterGE(int register_index,
 
 void RegExpMacroAssemblerIrregexp::IfRegisterEqPos(int register_index,
                                                    Label* on_eq) {
+  ASSERT(register_index >= 0);
+  ASSERT(register_index <= kMaxRegister);
   Emit(BC_CHECK_REGISTER_EQ_POS, register_index);
   EmitOrLink(on_eq);
 }

src/regexp-macro-assembler.h

@@ -38,6 +38,10 @@ struct DisjunctDecisionRow {
 
 class RegExpMacroAssembler {
  public:
+  // The implementation must be able to handle at least:
+  static const int kMaxRegister = (1 << 16) - 1;
+  static const int kMaxCPOffset = (1 << 15) - 1;
+  static const int kMinCPOffset = -(1 << 15);
   enum IrregexpImplementation {
     kIA32Implementation,
     kARMImplementation,