Unify kMaxArguments with number of bits used to encode it.

Increase the number of bits by 1 by making Flags unsigned.

BUG=chromium:211741

Review URL: https://chromiumcodereview.appspot.com/12886008

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13964 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/objects-inl.h

@@ -3869,8 +3869,9 @@ Code::Flags Code::ComputeFlags(Kind kind,
                                StubType type,
                                int argc,
                                InlineCacheHolderFlag holder) {
+  ASSERT(argc <= Code::kMaxArguments);
   // Compute the bit mask.
-  int bits = KindField::encode(kind)
+  unsigned int bits = KindField::encode(kind)
       | ICStateField::encode(ic_state)
       | TypeField::encode(type)
       | ExtraICStateField::encode(extra_ic_state)

src/objects.h

@@ -4302,8 +4302,8 @@ class Code: public HeapObject {
   // FLAGS_MIN_VALUE and FLAGS_MAX_VALUE are specified to ensure that
   // enumeration type has correct value range (see Issue 830 for more details).
   enum Flags {
-    FLAGS_MIN_VALUE = kMinInt,
-    FLAGS_MAX_VALUE = kMaxInt
+    FLAGS_MIN_VALUE = 0,
+    FLAGS_MAX_VALUE = kMaxUInt32
   };
 
 #define CODE_KIND_LIST(V) \
@@ -4784,6 +4784,9 @@ class Code: public HeapObject {
   // Signed field cannot be encoded using the BitField class.
   static const int kArgumentsCountShift = 17;
   static const int kArgumentsCountMask = ~((1 << kArgumentsCountShift) - 1);
+  static const int kArgumentsBits =
+      PlatformSmiTagging::kSmiValueSize - Code::kArgumentsCountShift + 1;
+  static const int kMaxArguments = (1 << kArgumentsBits) - 1;
 
   // This constant should be encodable in an ARM instruction.
   static const int kFlagsNotUsedInLookup =

src/parser.cc

@@ -4201,7 +4201,7 @@ ZoneList<Expression*>* Parser::ParseArguments(bool* ok) {
   while (!done) {
     Expression* argument = ParseAssignmentExpression(true, CHECK_OK);
     result->Add(argument, zone());
-    if (result->length() > kMaxNumFunctionParameters) {
+    if (result->length() > Code::kMaxArguments) {
       ReportMessageAt(scanner().location(), "too_many_arguments",
                       Vector<const char*>::empty());
       *ok = false;
@@ -4378,7 +4378,7 @@ FunctionLiteral* Parser::ParseFunctionLiteral(Handle<String> function_name,
 
       top_scope_->DeclareParameter(param_name, VAR);
       num_parameters++;
-      if (num_parameters > kMaxNumFunctionParameters) {
+      if (num_parameters > Code::kMaxArguments) {
         ReportMessageAt(scanner().location(), "too_many_parameters",
                         Vector<const char*>::empty());
         *ok = false;

src/parser.h

@@ -448,11 +448,6 @@ class Parser {
                        Vector<Handle<String> > args);
 
  private:
-  // Limit on number of function parameters is chosen arbitrarily.
-  // Code::Flags uses only the low 17 bits of num-parameters to
-  // construct a hashable id, so if more than 2^17 are allowed, this
-  // should be checked.
-  static const int kMaxNumFunctionParameters = 32766;
   static const int kMaxNumFunctionLocals = 131071;  // 2^17-1
 
   enum Mode {

src/stub-cache.cc

@@ -593,7 +593,7 @@ Handle<Code> StubCache::ComputeCallConstant(int argc,
   Handle<Code> code =
       compiler.CompileCallConstant(object, holder, name, check, function);
   code->set_check_type(check);
-  ASSERT_EQ(flags, code->flags());
+  ASSERT(flags == code->flags());
   PROFILE(isolate_,
           CodeCreateEvent(CALL_LOGGER_TAG(kind, CALL_IC_TAG), *code, *name));
   GDBJIT(AddCode(GDBJITInterface::CALL_IC, *name, *code));
@@ -633,7 +633,7 @@ Handle<Code> StubCache::ComputeCallField(int argc,
   Handle<Code> code =
       compiler.CompileCallField(Handle<JSObject>::cast(object),
                                 holder, index, name);
-  ASSERT_EQ(flags, code->flags());
+  ASSERT(flags == code->flags());
   PROFILE(isolate_,
           CodeCreateEvent(CALL_LOGGER_TAG(kind, CALL_IC_TAG), *code, *name));
   GDBJIT(AddCode(GDBJITInterface::CALL_IC, *name, *code));
@@ -672,7 +672,7 @@ Handle<Code> StubCache::ComputeCallInterceptor(int argc,
   Handle<Code> code =
       compiler.CompileCallInterceptor(Handle<JSObject>::cast(object),
                                       holder, name);
-  ASSERT_EQ(flags, code->flags());
+  ASSERT(flags == code->flags());
   PROFILE(isolate(),
           CodeCreateEvent(CALL_LOGGER_TAG(kind, CALL_IC_TAG), *code, *name));
   GDBJIT(AddCode(GDBJITInterface::CALL_IC, *name, *code));
@@ -702,7 +702,7 @@ Handle<Code> StubCache::ComputeCallGlobal(int argc,
   CallStubCompiler compiler(isolate(), argc, kind, extra_state, cache_holder);
   Handle<Code> code =
       compiler.CompileCallGlobal(receiver, holder, cell, function, name);
-  ASSERT_EQ(flags, code->flags());
+  ASSERT(flags == code->flags());
   PROFILE(isolate(),
           CodeCreateEvent(CALL_LOGGER_TAG(kind, CALL_IC_TAG), *code, *name));
   GDBJIT(AddCode(GDBJITInterface::CALL_IC, *name, *code));