# HG changeset patch
# User lfoltan
# Date 1571677996 14400
# Node ID cba8afa5cfed370c854581f8e186e47bcab57398
# Parent  ae0af9fb3dbbf4c23fb3c72751fade92a07e11d2
8231844: Enhance type signature characters in classfile_constants.h and improve the JVM to use type signature characters more consistently
Summary: Increase the use of type signature constants instead of hard coded characters within the JVM.
Reviewed-by: coleenp, dholmes, fparain
Contributed-by: lois.foltan@oracle.com, john.r.rose@oracle.com

diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/aot/aotCodeHeap.cpp
--- a/src/hotspot/share/aot/aotCodeHeap.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/aot/aotCodeHeap.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -93,7 +93,7 @@
   Handle protection_domain(thread, caller->method_holder()->protection_domain());
 
   // Ignore wrapping L and ;
-  if (name[0] == 'L') {
+  if (name[0] == JVM_SIGNATURE_CLASS) {
     assert(len > 2, "small name %s", name);
     name++;
     len -= 2;
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/c1/c1_InstructionPrinter.cpp
--- a/src/hotspot/share/c1/c1_InstructionPrinter.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/c1/c1_InstructionPrinter.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -33,19 +33,11 @@
 #ifndef PRODUCT
 
 const char* InstructionPrinter::basic_type_name(BasicType type) {
-  switch (type) {
-    case T_BOOLEAN: return "boolean";
-    case T_BYTE   : return "byte";
-    case T_CHAR   : return "char";
-    case T_SHORT  : return "short";
-    case T_INT    : return "int";
-    case T_LONG   : return "long";
-    case T_FLOAT  : return "float";
-    case T_DOUBLE : return "double";
-    case T_ARRAY  : return "array";
-    case T_OBJECT : return "object";
-    default       : return "???";
+  const char* n = type2name(type);
+  if (n == NULL || type > T_VOID) {
+    return "???";
   }
+  return n;
 }
 
 
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/ci/ciEnv.cpp
--- a/src/hotspot/share/ci/ciEnv.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/ci/ciEnv.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -413,8 +413,8 @@
 
   // Now we need to check the SystemDictionary
   Symbol* sym = name->get_symbol();
-  if (sym->char_at(0) == 'L' &&
-    sym->char_at(sym->utf8_length()-1) == ';') {
+  if (sym->char_at(0) == JVM_SIGNATURE_CLASS &&
+      sym->char_at(sym->utf8_length()-1) == JVM_SIGNATURE_ENDCLASS) {
     // This is a name from a signature.  Strip off the trimmings.
     // Call recursive to keep scope of strippedsym.
     TempNewSymbol strippedsym = SymbolTable::new_symbol(sym->as_utf8()+1,
@@ -440,7 +440,7 @@
 
   // setup up the proper type to return on OOM
   ciKlass* fail_type;
-  if (sym->char_at(0) == '[') {
+  if (sym->char_at(0) == JVM_SIGNATURE_ARRAY) {
     fail_type = _unloaded_ciobjarrayklass;
   } else {
     fail_type = _unloaded_ciinstance_klass;
@@ -466,8 +466,8 @@
   // we must build an array type around it.  The CI requires array klasses
   // to be loaded if their element klasses are loaded, except when memory
   // is exhausted.
-  if (sym->char_at(0) == '[' &&
-      (sym->char_at(1) == '[' || sym->char_at(1) == 'L')) {
+  if (sym->char_at(0) == JVM_SIGNATURE_ARRAY &&
+      (sym->char_at(1) == JVM_SIGNATURE_ARRAY || sym->char_at(1) == JVM_SIGNATURE_CLASS)) {
     // We have an unloaded array.
     // Build it on the fly if the element class exists.
     TempNewSymbol elem_sym = SymbolTable::new_symbol(sym->as_utf8()+1,
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/ci/ciInstanceKlass.cpp
--- a/src/hotspot/share/ci/ciInstanceKlass.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/ci/ciInstanceKlass.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -116,7 +116,7 @@
                                  jobject loader, jobject protection_domain)
   : ciKlass(name, T_OBJECT)
 {
-  assert(name->char_at(0) != '[', "not an instance klass");
+  assert(name->char_at(0) != JVM_SIGNATURE_ARRAY, "not an instance klass");
   _init_state = (InstanceKlass::ClassState)0;
   _nonstatic_field_size = -1;
   _has_nonstatic_fields = false;
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/ci/ciObjArrayKlass.cpp
--- a/src/hotspot/share/ci/ciObjArrayKlass.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/ci/ciObjArrayKlass.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -112,16 +112,16 @@
   Symbol* base_name_sym = element_name->get_symbol();
   char* name;
 
-  if (base_name_sym->char_at(0) == '[' ||
-      (base_name_sym->char_at(0) == 'L' &&  // watch package name 'Lxx'
-       base_name_sym->char_at(element_len-1) == ';')) {
+  if (base_name_sym->char_at(0) == JVM_SIGNATURE_ARRAY ||
+      (base_name_sym->char_at(0) == JVM_SIGNATURE_CLASS &&  // watch package name 'Lxx'
+       base_name_sym->char_at(element_len-1) == JVM_SIGNATURE_ENDCLASS)) {
 
     int new_len = element_len + dimension + 1; // for the ['s and '\0'
     name = CURRENT_THREAD_ENV->name_buffer(new_len);
 
     int pos = 0;
     for ( ; pos < dimension; pos++) {
-      name[pos] = '[';
+      name[pos] = JVM_SIGNATURE_ARRAY;
     }
     strncpy(name+pos, (char*)element_name->base(), element_len);
     name[new_len-1] = '\0';
@@ -133,11 +133,11 @@
     name = CURRENT_THREAD_ENV->name_buffer(new_len);
     int pos = 0;
     for ( ; pos < dimension; pos++) {
-      name[pos] = '[';
+      name[pos] = JVM_SIGNATURE_ARRAY;
     }
-    name[pos++] = 'L';
+    name[pos++] = JVM_SIGNATURE_CLASS;
     strncpy(name+pos, (char*)element_name->base(), element_len);
-    name[new_len-2] = ';';
+    name[new_len-2] = JVM_SIGNATURE_ENDCLASS;
     name[new_len-1] = '\0';
   }
   return ciSymbol::make(name);
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/ci/ciObjectFactory.cpp
--- a/src/hotspot/share/ci/ciObjectFactory.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/ci/ciObjectFactory.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -486,7 +486,7 @@
 
   // Two cases: this is an unloaded ObjArrayKlass or an
   // unloaded InstanceKlass.  Deal with both.
-  if (name->char_at(0) == '[') {
+  if (name->char_at(0) == JVM_SIGNATURE_ARRAY) {
     // Decompose the name.'
     FieldArrayInfo fd;
     BasicType element_type = FieldType::get_array_info(name->get_symbol(),
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/ci/ciReplay.cpp
--- a/src/hotspot/share/ci/ciReplay.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/ci/ciReplay.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -814,18 +814,18 @@
     }
 
     oop java_mirror = k->java_mirror();
-    if (field_signature[0] == '[') {
+    if (field_signature[0] == JVM_SIGNATURE_ARRAY) {
       int length = parse_int("array length");
       oop value = NULL;
 
-      if (field_signature[1] == '[') {
+      if (field_signature[1] == JVM_SIGNATURE_ARRAY) {
         // multi dimensional array
         ArrayKlass* kelem = (ArrayKlass *)parse_klass(CHECK);
         if (kelem == NULL) {
           return;
         }
         int rank = 0;
-        while (field_signature[rank] == '[') {
+        while (field_signature[rank] == JVM_SIGNATURE_ARRAY) {
           rank++;
         }
         jint* dims = NEW_RESOURCE_ARRAY(jint, rank);
@@ -851,7 +851,8 @@
           value = oopFactory::new_intArray(length, CHECK);
         } else if (strcmp(field_signature, "[J") == 0) {
           value = oopFactory::new_longArray(length, CHECK);
-        } else if (field_signature[0] == '[' && field_signature[1] == 'L') {
+        } else if (field_signature[0] == JVM_SIGNATURE_ARRAY &&
+                   field_signature[1] == JVM_SIGNATURE_CLASS) {
           Klass* kelem = resolve_klass(field_signature + 1, CHECK);
           value = oopFactory::new_objArray(kelem, length, CHECK);
         } else {
@@ -892,7 +893,7 @@
       } else if (strcmp(field_signature, "Ljava/lang/String;") == 0) {
         Handle value = java_lang_String::create_from_str(string_value, CHECK);
         java_mirror->obj_field_put(fd.offset(), value());
-      } else if (field_signature[0] == 'L') {
+      } else if (field_signature[0] == JVM_SIGNATURE_CLASS) {
         Klass* k = resolve_klass(string_value, CHECK);
         oop value = InstanceKlass::cast(k)->allocate_instance(CHECK);
         java_mirror->obj_field_put(fd.offset(), value);
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/classfile/classFileParser.cpp
--- a/src/hotspot/share/classfile/classFileParser.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/classfile/classFileParser.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -731,7 +731,7 @@
           const unsigned int name_len = name->utf8_length();
           if (tag == JVM_CONSTANT_Methodref &&
               name_len != 0 &&
-              name->char_at(0) == '<' &&
+              name->char_at(0) == JVM_SIGNATURE_SPECIAL &&
               name != vmSymbols::object_initializer_name()) {
             classfile_parse_error(
               "Bad method name at constant pool index %u in class file %s",
@@ -4961,24 +4961,25 @@
   if (length == 0) return false;  // Must have at least one char.
   for (const char* p = name; p != name + length; p++) {
     switch(*p) {
-      case '.':
-      case ';':
-      case '[':
+      case JVM_SIGNATURE_DOT:
+      case JVM_SIGNATURE_ENDCLASS:
+      case JVM_SIGNATURE_ARRAY:
         // do not permit '.', ';', or '['
         return false;
-      case '/':
+      case JVM_SIGNATURE_SLASH:
         // check for '//' or leading or trailing '/' which are not legal
         // unqualified name must not be empty
         if (type == ClassFileParser::LegalClass) {
-          if (p == name || p+1 >= name+length || *(p+1) == '/') {
+          if (p == name || p+1 >= name+length ||
+              *(p+1) == JVM_SIGNATURE_SLASH) {
             return false;
           }
         } else {
           return false;   // do not permit '/' unless it's class name
         }
         break;
-      case '<':
-      case '>':
+      case JVM_SIGNATURE_SPECIAL:
+      case JVM_SIGNATURE_ENDSPECIAL:
         // do not permit '<' or '>' in method names
         if (type == ClassFileParser::LegalMethod) {
           return false;
@@ -5015,7 +5016,7 @@
         last_is_slash = false;
         continue;
       }
-      if (slash_ok && ch == '/') {
+      if (slash_ok && ch == JVM_SIGNATURE_SLASH) {
         if (last_is_slash) {
           return NULL;  // Don't permit consecutive slashes
         }
@@ -5095,14 +5096,14 @@
         const char* const p = skip_over_field_name(signature + 1, true, --length);
 
         // The next character better be a semicolon
-        if (p && (p - signature) > 1 && p[0] == ';') {
+        if (p && (p - signature) > 1 && p[0] == JVM_SIGNATURE_ENDCLASS) {
           return p + 1;
         }
       }
       else {
         // Skip leading 'L' and ignore first appearance of ';'
         signature++;
-        const char* c = (const char*) memchr(signature, ';', length - 1);
+        const char* c = (const char*) memchr(signature, JVM_SIGNATURE_ENDCLASS, length - 1);
         // Format check signature
         if (c != NULL) {
           int newlen = c - (char*) signature;
@@ -5151,7 +5152,7 @@
       p = skip_over_field_signature(bytes, false, length, CHECK);
       legal = (p != NULL) && ((p - bytes) == (int)length);
     } else if (_major_version < JAVA_1_5_VERSION) {
-      if (bytes[0] != '<') {
+      if (bytes[0] != JVM_SIGNATURE_SPECIAL) {
         p = skip_over_field_name(bytes, true, length);
         legal = (p != NULL) && ((p - bytes) == (int)length);
       }
@@ -5186,7 +5187,7 @@
 
   if (length > 0) {
     if (_major_version < JAVA_1_5_VERSION) {
-      if (bytes[0] != '<') {
+      if (bytes[0] != JVM_SIGNATURE_SPECIAL) {
         const char* p = skip_over_field_name(bytes, false, length);
         legal = (p != NULL) && ((p - bytes) == (int)length);
       }
@@ -5219,7 +5220,7 @@
   bool legal = false;
 
   if (length > 0) {
-    if (bytes[0] == '<') {
+    if (bytes[0] == JVM_SIGNATURE_SPECIAL) {
       if (name == vmSymbols::object_initializer_name() || name == vmSymbols::class_initializer_name()) {
         legal = true;
       }
@@ -5303,7 +5304,7 @@
     // The first non-signature thing better be a ')'
     if ((length > 0) && (*p++ == JVM_SIGNATURE_ENDFUNC)) {
       length--;
-      if (name->utf8_length() > 0 && name->char_at(0) == '<') {
+      if (name->utf8_length() > 0 && name->char_at(0) == JVM_SIGNATURE_SPECIAL) {
         // All internal methods must return void
         if ((length == 1) && (p[0] == JVM_SIGNATURE_VOID)) {
           return args_size;
@@ -5705,7 +5706,7 @@
 // its _class_name field.
 void ClassFileParser::prepend_host_package_name(const InstanceKlass* unsafe_anonymous_host, TRAPS) {
   ResourceMark rm(THREAD);
-  assert(strrchr(_class_name->as_C_string(), '/') == NULL,
+  assert(strrchr(_class_name->as_C_string(), JVM_SIGNATURE_SLASH) == NULL,
          "Unsafe anonymous class should not be in a package");
   const char* host_pkg_name =
     ClassLoader::package_from_name(unsafe_anonymous_host->name()->as_C_string(), NULL);
@@ -5738,7 +5739,7 @@
   assert(_unsafe_anonymous_host != NULL, "Expected an unsafe anonymous class");
 
   const jbyte* anon_last_slash = UTF8::strrchr((const jbyte*)_class_name->base(),
-                                               _class_name->utf8_length(), '/');
+                                               _class_name->utf8_length(), JVM_SIGNATURE_SLASH);
   if (anon_last_slash == NULL) {  // Unnamed package
     prepend_host_package_name(_unsafe_anonymous_host, CHECK);
   } else {
@@ -6343,7 +6344,7 @@
   if (class_name != NULL) {
     ResourceMark rm;
     char* name = class_name->as_C_string();
-    return strchr(name, '.') == NULL;
+    return strchr(name, JVM_SIGNATURE_DOT) == NULL;
   } else {
     return true;
   }
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/classfile/classLoader.cpp
--- a/src/hotspot/share/classfile/classLoader.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/classfile/classLoader.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -187,7 +187,7 @@
     *bad_class_name = false;
   }
 
-  const char* const last_slash = strrchr(class_name, '/');
+  const char* const last_slash = strrchr(class_name, JVM_SIGNATURE_SLASH);
   if (last_slash == NULL) {
     // No package name
     return NULL;
@@ -195,16 +195,16 @@
 
   char* class_name_ptr = (char*) class_name;
   // Skip over '['s
-  if (*class_name_ptr == '[') {
+  if (*class_name_ptr == JVM_SIGNATURE_ARRAY) {
     do {
       class_name_ptr++;
-    } while (*class_name_ptr == '[');
+    } while (*class_name_ptr == JVM_SIGNATURE_ARRAY);
 
     // Fully qualified class names should not contain a 'L'.
     // Set bad_class_name to true to indicate that the package name
     // could not be obtained due to an error condition.
     // In this situation, is_same_class_package returns false.
-    if (*class_name_ptr == 'L') {
+    if (*class_name_ptr == JVM_SIGNATURE_CLASS) {
       if (bad_class_name != NULL) {
         *bad_class_name = true;
       }
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/classfile/javaAssertions.cpp
--- a/src/hotspot/share/classfile/javaAssertions.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/classfile/javaAssertions.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -79,7 +79,7 @@
   // JVM_DesiredAssertionStatus pass the external_name() to
   // JavaAssertion::enabled(), but that is done once per loaded class.
   for (int i = 0; i < len; ++i) {
-    if (name_copy[i] == '.') name_copy[i] = '/';
+    if (name_copy[i] == JVM_SIGNATURE_DOT) name_copy[i] = JVM_SIGNATURE_SLASH;
   }
 
   if (TraceJavaAssertions) {
@@ -135,7 +135,7 @@
   for (index = len - 1; p != 0; p = p->next(), --index) {
     assert(index >= 0, "length does not match list");
     Handle s = java_lang_String::create_from_str(p->name(), CHECK);
-    s = java_lang_String::char_converter(s, '/', '.', CHECK);
+    s = java_lang_String::char_converter(s, JVM_SIGNATURE_SLASH, JVM_SIGNATURE_DOT, CHECK);
     names->obj_at_put(index, s());
     enabled->bool_at_put(index, p->enabled());
   }
@@ -163,10 +163,10 @@
   // does not include a package, length will be 0 which will match items for the
   // default package (from options "-ea:..."  or "-da:...").
   size_t len = strlen(classname);
-  for (/* empty */; len > 0 && classname[len] != '/'; --len) /* empty */;
+  for (/* empty */; len > 0 && classname[len] != JVM_SIGNATURE_SLASH; --len) /* empty */;
 
   do {
-    assert(len == 0 || classname[len] == '/', "not a package name");
+    assert(len == 0 || classname[len] == JVM_SIGNATURE_SLASH, "not a package name");
     for (OptionList* p = _packages; p != 0; p = p->next()) {
       if (strncmp(p->name(), classname, len) == 0 && p->name()[len] == '\0') {
         return p;
@@ -175,7 +175,7 @@
 
     // Find the length of the next package, taking care to avoid decrementing
     // past 0 (len is unsigned).
-    while (len > 0 && classname[--len] != '/') /* empty */;
+    while (len > 0 && classname[--len] != JVM_SIGNATURE_SLASH) /* empty */;
   } while (len > 0);
 
   return 0;
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/classfile/javaClasses.hpp
--- a/src/hotspot/share/classfile/javaClasses.hpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/classfile/javaClasses.hpp	Mon Oct 21 13:13:16 2019 -0400
@@ -201,7 +201,9 @@
   static inline bool value_equals(typeArrayOop str_value1, typeArrayOop str_value2);
 
   // Conversion between '.' and '/' formats
-  static Handle externalize_classname(Handle java_string, TRAPS) { return char_converter(java_string, '/', '.', THREAD); }
+  static Handle externalize_classname(Handle java_string, TRAPS) {
+    return char_converter(java_string, JVM_SIGNATURE_SLASH, JVM_SIGNATURE_DOT, THREAD);
+  }
 
   // Conversion
   static Symbol* as_symbol(oop java_string);
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/classfile/modules.cpp
--- a/src/hotspot/share/classfile/modules.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/classfile/modules.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -331,7 +331,7 @@
     if (!h_loader.is_null() &&
         !SystemDictionary::is_platform_class_loader(h_loader()) &&
         (strncmp(package_name, JAVAPKG, JAVAPKG_LEN) == 0 &&
-          (package_name[JAVAPKG_LEN] == '/' || package_name[JAVAPKG_LEN] == '\0'))) {
+          (package_name[JAVAPKG_LEN] == JVM_SIGNATURE_SLASH || package_name[JAVAPKG_LEN] == '\0'))) {
       const char* class_loader_name = loader_data->loader_name_and_id();
       size_t pkg_len = strlen(package_name);
       char* pkg_name = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, pkg_len + 1);
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/classfile/systemDictionary.cpp
--- a/src/hotspot/share/classfile/systemDictionary.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/classfile/systemDictionary.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -2533,7 +2533,7 @@
 
     // It's a primitive.  (Void has a primitive mirror too.)
     char ch = type->char_at(0);
-    assert(is_java_primitive(char2type(ch)) || ch == 'V', "");
+    assert(is_java_primitive(char2type(ch)) || ch == JVM_SIGNATURE_VOID, "");
     return Handle(THREAD, find_java_mirror_for_type(ch));
 
   } else if (FieldType::is_obj(type) || FieldType::is_array(type)) {
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/classfile/verificationType.cpp
--- a/src/hotspot/share/classfile/verificationType.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/classfile/verificationType.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -122,19 +122,19 @@
   assert(is_array() && name()->utf8_length() >= 2, "Must be a valid array");
   Symbol* component;
   switch (name()->char_at(1)) {
-    case 'Z': return VerificationType(Boolean);
-    case 'B': return VerificationType(Byte);
-    case 'C': return VerificationType(Char);
-    case 'S': return VerificationType(Short);
-    case 'I': return VerificationType(Integer);
-    case 'J': return VerificationType(Long);
-    case 'F': return VerificationType(Float);
-    case 'D': return VerificationType(Double);
-    case '[':
+    case JVM_SIGNATURE_BOOLEAN: return VerificationType(Boolean);
+    case JVM_SIGNATURE_BYTE:    return VerificationType(Byte);
+    case JVM_SIGNATURE_CHAR:    return VerificationType(Char);
+    case JVM_SIGNATURE_SHORT:   return VerificationType(Short);
+    case JVM_SIGNATURE_INT:     return VerificationType(Integer);
+    case JVM_SIGNATURE_LONG:    return VerificationType(Long);
+    case JVM_SIGNATURE_FLOAT:   return VerificationType(Float);
+    case JVM_SIGNATURE_DOUBLE:  return VerificationType(Double);
+    case JVM_SIGNATURE_ARRAY:
       component = context->create_temporary_symbol(
         name(), 1, name()->utf8_length());
       return VerificationType::reference_type(component);
-    case 'L':
+    case JVM_SIGNATURE_CLASS:
       component = context->create_temporary_symbol(
         name(), 2, name()->utf8_length() - 1);
       return VerificationType::reference_type(component);
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/classfile/verificationType.hpp
--- a/src/hotspot/share/classfile/verificationType.hpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/classfile/verificationType.hpp	Mon Oct 21 13:13:16 2019 -0400
@@ -209,24 +209,24 @@
   bool is_x_array(char sig) const {
     return is_null() || (is_array() && (name()->char_at(1) == sig));
   }
-  bool is_int_array() const { return is_x_array('I'); }
-  bool is_byte_array() const { return is_x_array('B'); }
-  bool is_bool_array() const { return is_x_array('Z'); }
-  bool is_char_array() const { return is_x_array('C'); }
-  bool is_short_array() const { return is_x_array('S'); }
-  bool is_long_array() const { return is_x_array('J'); }
-  bool is_float_array() const { return is_x_array('F'); }
-  bool is_double_array() const { return is_x_array('D'); }
-  bool is_object_array() const { return is_x_array('L'); }
-  bool is_array_array() const { return is_x_array('['); }
+  bool is_int_array() const { return is_x_array(JVM_SIGNATURE_INT); }
+  bool is_byte_array() const { return is_x_array(JVM_SIGNATURE_BYTE); }
+  bool is_bool_array() const { return is_x_array(JVM_SIGNATURE_BOOLEAN); }
+  bool is_char_array() const { return is_x_array(JVM_SIGNATURE_CHAR); }
+  bool is_short_array() const { return is_x_array(JVM_SIGNATURE_SHORT); }
+  bool is_long_array() const { return is_x_array(JVM_SIGNATURE_LONG); }
+  bool is_float_array() const { return is_x_array(JVM_SIGNATURE_FLOAT); }
+  bool is_double_array() const { return is_x_array(JVM_SIGNATURE_DOUBLE); }
+  bool is_object_array() const { return is_x_array(JVM_SIGNATURE_CLASS); }
+  bool is_array_array() const { return is_x_array(JVM_SIGNATURE_ARRAY); }
   bool is_reference_array() const
     { return is_object_array() || is_array_array(); }
   bool is_object() const
     { return (is_reference() && !is_null() && name()->utf8_length() >= 1 &&
-              name()->char_at(0) != '['); }
+              name()->char_at(0) != JVM_SIGNATURE_ARRAY); }
   bool is_array() const
     { return (is_reference() && !is_null() && name()->utf8_length() >= 2 &&
-              name()->char_at(0) == '['); }
+              name()->char_at(0) == JVM_SIGNATURE_ARRAY); }
   bool is_uninitialized() const
     { return ((_u._data & Uninitialized) == Uninitialized); }
   bool is_uninitialized_this() const
@@ -322,7 +322,7 @@
   int dimensions() const {
     assert(is_array(), "Must be an array");
     int index = 0;
-    while (name()->char_at(index) == '[') index++;
+    while (name()->char_at(index) == JVM_SIGNATURE_ARRAY) index++;
     return index;
   }
 
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/classfile/verifier.cpp
--- a/src/hotspot/share/classfile/verifier.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/classfile/verifier.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -2852,7 +2852,7 @@
     }
   }
 
-  if (method_name->char_at(0) == '<') {
+  if (method_name->char_at(0) == JVM_SIGNATURE_SPECIAL) {
     // Make sure <init> can only be invoked by invokespecial
     if (opcode != Bytecodes::_invokespecial ||
         method_name != vmSymbols::object_initializer_name()) {
@@ -3028,21 +3028,23 @@
     // Check for more than MAX_ARRAY_DIMENSIONS
     length = (int)strlen(component_name);
     if (length > MAX_ARRAY_DIMENSIONS &&
-        component_name[MAX_ARRAY_DIMENSIONS - 1] == '[') {
+        component_name[MAX_ARRAY_DIMENSIONS - 1] == JVM_SIGNATURE_ARRAY) {
       verify_error(ErrorContext::bad_code(bci),
         "Illegal anewarray instruction, array has more than 255 dimensions");
     }
     // add one dimension to component
     length++;
     arr_sig_str = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, length + 1);
-    int n = os::snprintf(arr_sig_str, length + 1, "[%s", component_name);
+    int n = os::snprintf(arr_sig_str, length + 1, "%c%s",
+                         JVM_SIGNATURE_ARRAY, component_name);
     assert(n == length, "Unexpected number of characters in string");
   } else {         // it's an object or interface
     const char* component_name = component_type.name()->as_utf8();
     // add one dimension to component with 'L' prepended and ';' postpended.
     length = (int)strlen(component_name) + 3;
     arr_sig_str = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, length + 1);
-    int n = os::snprintf(arr_sig_str, length + 1, "[L%s;", component_name);
+    int n = os::snprintf(arr_sig_str, length + 1, "%c%c%s;",
+                         JVM_SIGNATURE_ARRAY, JVM_SIGNATURE_CLASS, component_name);
     assert(n == length, "Unexpected number of characters in string");
   }
   Symbol* arr_sig = create_temporary_symbol(arr_sig_str, length);
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/classfile/vmSymbols.cpp
--- a/src/hotspot/share/classfile/vmSymbols.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/classfile/vmSymbols.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -970,7 +970,7 @@
   case F_RNY:fname = "native synchronized "; break;
   default:   break;
   }
-  const char* kptr = strrchr(kname, '/');
+  const char* kptr = strrchr(kname, JVM_SIGNATURE_SLASH);
   if (kptr != NULL)  kname = kptr + 1;
   int len = jio_snprintf(buf, buflen, "%s: %s%s.%s%s",
                          str, fname, kname, mname, sname);
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/compiler/methodMatcher.cpp
--- a/src/hotspot/share/compiler/methodMatcher.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/compiler/methodMatcher.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -264,11 +264,13 @@
     c_match = check_mode(class_name, error_msg);
     m_match = check_mode(method_name, error_msg);
 
-    if ((strchr(class_name, '<') != NULL) || (strchr(class_name, '>') != NULL)) {
+    if ((strchr(class_name, JVM_SIGNATURE_SPECIAL) != NULL) ||
+        (strchr(class_name, JVM_SIGNATURE_ENDSPECIAL) != NULL)) {
       error_msg = "Chars '<' and '>' not allowed in class name";
       return;
     }
-    if ((strchr(method_name, '<') != NULL) || (strchr(method_name, '>') != NULL)) {
+    if ((strchr(method_name, JVM_SIGNATURE_SPECIAL) != NULL) ||
+        (strchr(method_name, JVM_SIGNATURE_ENDSPECIAL) != NULL)) {
       if ((strncmp("<init>", method_name, 255) != 0) && (strncmp("<clinit>", method_name, 255) != 0)) {
         error_msg = "Chars '<' and '>' only allowed in <init> and <clinit>";
         return;
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/interpreter/interpreterRuntime.cpp
--- a/src/hotspot/share/interpreter/interpreterRuntime.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/interpreter/interpreterRuntime.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -1249,15 +1249,15 @@
   char sig_type = '\0';
 
   switch(cp_entry->flag_state()) {
-    case btos: sig_type = 'B'; break;
-    case ztos: sig_type = 'Z'; break;
-    case ctos: sig_type = 'C'; break;
-    case stos: sig_type = 'S'; break;
-    case itos: sig_type = 'I'; break;
-    case ftos: sig_type = 'F'; break;
-    case atos: sig_type = 'L'; break;
-    case ltos: sig_type = 'J'; break;
-    case dtos: sig_type = 'D'; break;
+    case btos: sig_type = JVM_SIGNATURE_BYTE;    break;
+    case ztos: sig_type = JVM_SIGNATURE_BOOLEAN; break;
+    case ctos: sig_type = JVM_SIGNATURE_CHAR;    break;
+    case stos: sig_type = JVM_SIGNATURE_SHORT;   break;
+    case itos: sig_type = JVM_SIGNATURE_INT;     break;
+    case ftos: sig_type = JVM_SIGNATURE_FLOAT;   break;
+    case atos: sig_type = JVM_SIGNATURE_CLASS;   break;
+    case ltos: sig_type = JVM_SIGNATURE_LONG;    break;
+    case dtos: sig_type = JVM_SIGNATURE_DOUBLE;  break;
     default:  ShouldNotReachHere(); return;
   }
   bool is_static = (obj == NULL);
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/jvmci/compilerRuntime.cpp
--- a/src/hotspot/share/jvmci/compilerRuntime.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/jvmci/compilerRuntime.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -73,7 +73,7 @@
   Handle protection_domain(THREAD, caller->method_holder()->protection_domain());
 
   // Ignore wrapping L and ;
-  if (name[0] == 'L') {
+  if (name[0] == JVM_SIGNATURE_CLASS) {
     assert(len > 2, "small name %s", name);
     name++;
     len -= 2;
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/jvmci/jvmciCompilerToVM.cpp
--- a/src/hotspot/share/jvmci/jvmciCompilerToVM.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/jvmci/jvmciCompilerToVM.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -535,8 +535,8 @@
       JVMCI_THROW_MSG_NULL(ClassNotFoundException, str);
     }
   } else {
-    if (class_name->char_at(0) == 'L' &&
-      class_name->char_at(class_name->utf8_length()-1) == ';') {
+    if (class_name->char_at(0) == JVM_SIGNATURE_CLASS &&
+        class_name->char_at(class_name->utf8_length()-1) == JVM_SIGNATURE_ENDCLASS) {
       // This is a name from a signature.  Strip off the trimmings.
       // Call recursive to keep scope of strippedsym.
       TempNewSymbol strippedsym = SymbolTable::new_symbol(class_name->as_utf8()+1,
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/jvmci/jvmciRuntime.cpp
--- a/src/hotspot/share/jvmci/jvmciRuntime.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/jvmci/jvmciRuntime.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -980,8 +980,8 @@
   JVMCI_EXCEPTION_CONTEXT;
 
   // Now we need to check the SystemDictionary
-  if (sym->char_at(0) == 'L' &&
-    sym->char_at(sym->utf8_length()-1) == ';') {
+  if (sym->char_at(0) == JVM_SIGNATURE_CLASS &&
+      sym->char_at(sym->utf8_length()-1) == JVM_SIGNATURE_ENDCLASS) {
     // This is a name from a signature.  Strip off the trimmings.
     // Call recursive to keep scope of strippedsym.
     TempNewSymbol strippedsym = SymbolTable::new_symbol(sym->as_utf8()+1,
@@ -1013,8 +1013,8 @@
   // we must build an array type around it.  The CI requires array klasses
   // to be loaded if their element klasses are loaded, except when memory
   // is exhausted.
-  if (sym->char_at(0) == '[' &&
-      (sym->char_at(1) == '[' || sym->char_at(1) == 'L')) {
+  if (sym->char_at(0) == JVM_SIGNATURE_ARRAY &&
+      (sym->char_at(1) == JVM_SIGNATURE_ARRAY || sym->char_at(1) == JVM_SIGNATURE_CLASS)) {
     // We have an unloaded array.
     // Build it on the fly if the element class exists.
     TempNewSymbol elem_sym = SymbolTable::new_symbol(sym->as_utf8()+1,
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/memory/heapInspection.cpp
--- a/src/hotspot/share/memory/heapInspection.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/memory/heapInspection.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2002, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2002, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -72,8 +72,8 @@
   ResourceMark rm;
   const char* name1 = e1->klass()->external_name();
   const char* name2 = e2->klass()->external_name();
-  bool d1 = (name1[0] == '[');
-  bool d2 = (name2[0] == '[');
+  bool d1 = (name1[0] == JVM_SIGNATURE_ARRAY);
+  bool d2 = (name2[0] == JVM_SIGNATURE_ARRAY);
   if (d1 && !d2) {
     return -1;
   } else if (d2 && !d1) {
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/oops/generateOopMap.cpp
--- a/src/hotspot/share/oops/generateOopMap.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/oops/generateOopMap.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -1993,14 +1993,14 @@
 // This is used to parse the signature for fields, since they are very simple...
 CellTypeState *GenerateOopMap::sigchar_to_effect(char sigch, int bci, CellTypeState *out) {
   // Object and array
-  if (sigch=='L' || sigch=='[') {
+  if (sigch==JVM_SIGNATURE_CLASS || sigch==JVM_SIGNATURE_ARRAY) {
     out[0] = CellTypeState::make_line_ref(bci);
     out[1] = CellTypeState::bottom;
     return out;
   }
-  if (sigch == 'J' || sigch == 'D' ) return vvCTS;  // Long and Double
-  if (sigch == 'V' ) return epsilonCTS;             // Void
-  return vCTS;                                      // Otherwise
+  if (sigch == JVM_SIGNATURE_LONG || sigch == JVM_SIGNATURE_DOUBLE) return vvCTS;  // Long and Double
+  if (sigch == JVM_SIGNATURE_VOID) return epsilonCTS; // Void
+  return vCTS;                                        // Otherwise
 }
 
 long GenerateOopMap::_total_byte_count = 0;
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/oops/instanceKlass.cpp
--- a/src/hotspot/share/oops/instanceKlass.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/oops/instanceKlass.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -2594,7 +2594,7 @@
 
   // Add L as type indicator
   int dest_index = 0;
-  dest[dest_index++] = 'L';
+  dest[dest_index++] = JVM_SIGNATURE_CLASS;
 
   // Add the actual class name
   for (int src_index = 0; src_index < src_length; ) {
@@ -2607,7 +2607,7 @@
   }
 
   // Add the semicolon and the NULL
-  dest[dest_index++] = ';';
+  dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
   dest[dest_index] = '\0';
   return dest;
 }
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/oops/objArrayKlass.cpp
--- a/src/hotspot/share/oops/objArrayKlass.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/oops/objArrayKlass.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -106,14 +106,14 @@
     int len = element_klass->name()->utf8_length();
     char *new_str = NEW_RESOURCE_ARRAY(char, len + 4);
     int idx = 0;
-    new_str[idx++] = '[';
+    new_str[idx++] = JVM_SIGNATURE_ARRAY;
     if (element_klass->is_instance_klass()) { // it could be an array or simple type
-      new_str[idx++] = 'L';
+      new_str[idx++] = JVM_SIGNATURE_CLASS;
     }
     memcpy(&new_str[idx], name_str, len * sizeof(char));
     idx += len;
     if (element_klass->is_instance_klass()) {
-      new_str[idx++] = ';';
+      new_str[idx++] = JVM_SIGNATURE_ENDCLASS;
     }
     new_str[idx++] = '\0';
     name = SymbolTable::new_permanent_symbol(new_str);
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/oops/symbol.cpp
--- a/src/hotspot/share/oops/symbol.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/oops/symbol.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -201,8 +201,8 @@
   int   length = (int)strlen(str);
   // Turn all '/'s into '.'s (also for array klasses)
   for (int index = 0; index < length; index++) {
-    if (str[index] == '/') {
-      str[index] = '.';
+    if (str[index] == JVM_SIGNATURE_SLASH) {
+      str[index] = JVM_SIGNATURE_DOT;
     }
   }
   return str;
@@ -210,8 +210,8 @@
 
 static void print_class(outputStream *os, char *class_str, int len) {
   for (int i = 0; i < len; ++i) {
-    if (class_str[i] == '/') {
-      os->put('.');
+    if (class_str[i] == JVM_SIGNATURE_SLASH) {
+      os->put(JVM_SIGNATURE_DOT);
     } else {
       os->put(class_str[i]);
     }
@@ -221,9 +221,9 @@
 static void print_array(outputStream *os, char *array_str, int len) {
   int dimensions = 0;
   for (int i = 0; i < len; ++i) {
-    if (array_str[i] == '[') {
+    if (array_str[i] == JVM_SIGNATURE_ARRAY) {
       dimensions++;
-    } else if (array_str[i] == 'L') {
+    } else if (array_str[i] == JVM_SIGNATURE_CLASS) {
       // Expected format: L<type name>;. Skip 'L' and ';' delimiting the type name.
       print_class(os, array_str+i+1, len-i-2);
       break;
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/prims/jni.cpp
--- a/src/hotspot/share/prims/jni.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/prims/jni.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -2151,7 +2151,7 @@
   if (JvmtiExport::should_post_field_modification()) {
     jvalue field_value;
     field_value.l = value;
-    o = JvmtiExport::jni_SetField_probe_nh(thread, obj, o, k, fieldID, false, 'L', (jvalue *)&field_value);
+    o = JvmtiExport::jni_SetField_probe_nh(thread, obj, o, k, fieldID, false, JVM_SIGNATURE_CLASS, (jvalue *)&field_value);
   }
   HeapAccess<ON_UNKNOWN_OOP_REF>::oop_store_at(o, offset, JNIHandles::resolve(value));
   HOTSPOT_JNI_SETOBJECTFIELD_RETURN();
@@ -2177,34 +2177,34 @@
     field_value.unionType = value; \
     o = JvmtiExport::jni_SetField_probe_nh(thread, obj, o, k, fieldID, false, SigType, (jvalue *)&field_value); \
   } \
-  if (SigType == 'Z') { value = ((jboolean)value) & 1; } \
+  if (SigType == JVM_SIGNATURE_BOOLEAN) { value = ((jboolean)value) & 1; } \
   o->Fieldname##_field_put(offset, value); \
   ReturnProbe; \
 JNI_END
 
-DEFINE_SETFIELD(jboolean, bool,   Boolean, 'Z', z
+DEFINE_SETFIELD(jboolean, bool,   Boolean, JVM_SIGNATURE_BOOLEAN, z
                 , HOTSPOT_JNI_SETBOOLEANFIELD_ENTRY(env, obj, (uintptr_t)fieldID, value),
                 HOTSPOT_JNI_SETBOOLEANFIELD_RETURN())
-DEFINE_SETFIELD(jbyte,    byte,   Byte,    'B', b
+DEFINE_SETFIELD(jbyte,    byte,   Byte,    JVM_SIGNATURE_BYTE, b
                 , HOTSPOT_JNI_SETBYTEFIELD_ENTRY(env, obj, (uintptr_t)fieldID, value),
                 HOTSPOT_JNI_SETBYTEFIELD_RETURN())
-DEFINE_SETFIELD(jchar,    char,   Char,    'C', c
+DEFINE_SETFIELD(jchar,    char,   Char,    JVM_SIGNATURE_CHAR, c
                 , HOTSPOT_JNI_SETCHARFIELD_ENTRY(env, obj, (uintptr_t)fieldID, value),
                 HOTSPOT_JNI_SETCHARFIELD_RETURN())
-DEFINE_SETFIELD(jshort,   short,  Short,   'S', s
+DEFINE_SETFIELD(jshort,   short,  Short,   JVM_SIGNATURE_SHORT, s
                 , HOTSPOT_JNI_SETSHORTFIELD_ENTRY(env, obj, (uintptr_t)fieldID, value),
                 HOTSPOT_JNI_SETSHORTFIELD_RETURN())
-DEFINE_SETFIELD(jint,     int,    Int,     'I', i
+DEFINE_SETFIELD(jint,     int,    Int,     JVM_SIGNATURE_INT, i
                 , HOTSPOT_JNI_SETINTFIELD_ENTRY(env, obj, (uintptr_t)fieldID, value),
                 HOTSPOT_JNI_SETINTFIELD_RETURN())
-DEFINE_SETFIELD(jlong,    long,   Long,    'J', j
+DEFINE_SETFIELD(jlong,    long,   Long,    JVM_SIGNATURE_LONG, j
                 , HOTSPOT_JNI_SETLONGFIELD_ENTRY(env, obj, (uintptr_t)fieldID, value),
                 HOTSPOT_JNI_SETLONGFIELD_RETURN())
 // Float and double probes don't return value because dtrace doesn't currently support it
-DEFINE_SETFIELD(jfloat,   float,  Float,   'F', f
+DEFINE_SETFIELD(jfloat,   float,  Float,   JVM_SIGNATURE_FLOAT, f
                 , HOTSPOT_JNI_SETFLOATFIELD_ENTRY(env, obj, (uintptr_t)fieldID),
                 HOTSPOT_JNI_SETFLOATFIELD_RETURN())
-DEFINE_SETFIELD(jdouble,  double, Double,  'D', d
+DEFINE_SETFIELD(jdouble,  double, Double,  JVM_SIGNATURE_DOUBLE, d
                 , HOTSPOT_JNI_SETDOUBLEFIELD_ENTRY(env, obj, (uintptr_t)fieldID),
                 HOTSPOT_JNI_SETDOUBLEFIELD_RETURN())
 
@@ -2352,7 +2352,7 @@
   if (JvmtiExport::should_post_field_modification()) {
     jvalue field_value;
     field_value.l = value;
-    JvmtiExport::jni_SetField_probe(thread, NULL, NULL, id->holder(), fieldID, true, 'L', (jvalue *)&field_value);
+    JvmtiExport::jni_SetField_probe(thread, NULL, NULL, id->holder(), fieldID, true, JVM_SIGNATURE_CLASS, (jvalue *)&field_value);
   }
   id->holder()->java_mirror()->obj_field_put(id->offset(), JNIHandles::resolve(value));
   HOTSPOT_JNI_SETSTATICOBJECTFIELD_RETURN();
@@ -2376,34 +2376,34 @@
     field_value.unionType = value; \
     JvmtiExport::jni_SetField_probe(thread, NULL, NULL, id->holder(), fieldID, true, SigType, (jvalue *)&field_value); \
   } \
-  if (SigType == 'Z') { value = ((jboolean)value) & 1; } \
+  if (SigType == JVM_SIGNATURE_BOOLEAN) { value = ((jboolean)value) & 1; } \
   id->holder()->java_mirror()-> Fieldname##_field_put (id->offset(), value); \
   ReturnProbe;\
 JNI_END
 
-DEFINE_SETSTATICFIELD(jboolean, bool,   Boolean, 'Z', z
+DEFINE_SETSTATICFIELD(jboolean, bool,   Boolean, JVM_SIGNATURE_BOOLEAN, z
                       , HOTSPOT_JNI_SETSTATICBOOLEANFIELD_ENTRY(env, clazz, (uintptr_t)fieldID, value),
                       HOTSPOT_JNI_SETSTATICBOOLEANFIELD_RETURN())
-DEFINE_SETSTATICFIELD(jbyte,    byte,   Byte,    'B', b
+DEFINE_SETSTATICFIELD(jbyte,    byte,   Byte,    JVM_SIGNATURE_BYTE, b
                       , HOTSPOT_JNI_SETSTATICBYTEFIELD_ENTRY(env, clazz, (uintptr_t) fieldID, value),
                       HOTSPOT_JNI_SETSTATICBYTEFIELD_RETURN())
-DEFINE_SETSTATICFIELD(jchar,    char,   Char,    'C', c
+DEFINE_SETSTATICFIELD(jchar,    char,   Char,    JVM_SIGNATURE_CHAR, c
                       , HOTSPOT_JNI_SETSTATICCHARFIELD_ENTRY(env, clazz, (uintptr_t) fieldID, value),
                       HOTSPOT_JNI_SETSTATICCHARFIELD_RETURN())
-DEFINE_SETSTATICFIELD(jshort,   short,  Short,   'S', s
+DEFINE_SETSTATICFIELD(jshort,   short,  Short,   JVM_SIGNATURE_SHORT, s
                       , HOTSPOT_JNI_SETSTATICSHORTFIELD_ENTRY(env, clazz, (uintptr_t) fieldID, value),
                       HOTSPOT_JNI_SETSTATICSHORTFIELD_RETURN())
-DEFINE_SETSTATICFIELD(jint,     int,    Int,     'I', i
+DEFINE_SETSTATICFIELD(jint,     int,    Int,     JVM_SIGNATURE_INT, i
                       , HOTSPOT_JNI_SETSTATICINTFIELD_ENTRY(env, clazz, (uintptr_t) fieldID, value),
                       HOTSPOT_JNI_SETSTATICINTFIELD_RETURN())
-DEFINE_SETSTATICFIELD(jlong,    long,   Long,    'J', j
+DEFINE_SETSTATICFIELD(jlong,    long,   Long,    JVM_SIGNATURE_LONG, j
                       , HOTSPOT_JNI_SETSTATICLONGFIELD_ENTRY(env, clazz, (uintptr_t) fieldID, value),
                       HOTSPOT_JNI_SETSTATICLONGFIELD_RETURN())
 // Float and double probes don't return value because dtrace doesn't currently support it
-DEFINE_SETSTATICFIELD(jfloat,   float,  Float,   'F', f
+DEFINE_SETSTATICFIELD(jfloat,   float,  Float,   JVM_SIGNATURE_FLOAT, f
                       , HOTSPOT_JNI_SETSTATICFLOATFIELD_ENTRY(env, clazz, (uintptr_t) fieldID),
                       HOTSPOT_JNI_SETSTATICFLOATFIELD_RETURN())
-DEFINE_SETSTATICFIELD(jdouble,  double, Double,  'D', d
+DEFINE_SETSTATICFIELD(jdouble,  double, Double,  JVM_SIGNATURE_DOUBLE, d
                       , HOTSPOT_JNI_SETSTATICDOUBLEFIELD_ENTRY(env, clazz, (uintptr_t) fieldID),
                       HOTSPOT_JNI_SETSTATICDOUBLEFIELD_RETURN())
 
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/prims/jvmtiEnvBase.cpp
--- a/src/hotspot/share/prims/jvmtiEnvBase.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/prims/jvmtiEnvBase.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -1361,7 +1361,7 @@
     NULL_CHECK(ob_k, JVMTI_ERROR_INVALID_OBJECT);
 
     // Method return type signature.
-    char* ty_sign = 1 + strchr(signature->as_C_string(), ')');
+    char* ty_sign = 1 + strchr(signature->as_C_string(), JVM_SIGNATURE_ENDFUNC);
 
     if (!VM_GetOrSetLocal::is_assignable(ty_sign, ob_k, current_thread)) {
       return JVMTI_ERROR_TYPE_MISMATCH;
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/prims/jvmtiExport.cpp
--- a/src/hotspot/share/prims/jvmtiExport.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/prims/jvmtiExport.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -1994,7 +1994,9 @@
   address location, Klass* field_klass, Handle object, jfieldID field,
   char sig_type, jvalue *value) {
 
-  if (sig_type == 'I' || sig_type == 'Z' || sig_type == 'B' || sig_type == 'C' || sig_type == 'S') {
+  if (sig_type == JVM_SIGNATURE_INT || sig_type == JVM_SIGNATURE_BOOLEAN ||
+      sig_type == JVM_SIGNATURE_BYTE || sig_type == JVM_SIGNATURE_CHAR ||
+      sig_type == JVM_SIGNATURE_SHORT) {
     // 'I' instructions are used for byte, char, short and int.
     // determine which it really is, and convert
     fieldDescriptor fd;
@@ -2005,22 +2007,22 @@
       // convert value from int to appropriate type
       switch (fd.field_type()) {
       case T_BOOLEAN:
-        sig_type = 'Z';
+        sig_type = JVM_SIGNATURE_BOOLEAN;
         value->i = 0; // clear it
         value->z = (jboolean)ival;
         break;
       case T_BYTE:
-        sig_type = 'B';
+        sig_type = JVM_SIGNATURE_BYTE;
         value->i = 0; // clear it
         value->b = (jbyte)ival;
         break;
       case T_CHAR:
-        sig_type = 'C';
+        sig_type = JVM_SIGNATURE_CHAR;
         value->i = 0; // clear it
         value->c = (jchar)ival;
         break;
       case T_SHORT:
-        sig_type = 'S';
+        sig_type = JVM_SIGNATURE_SHORT;
         value->i = 0; // clear it
         value->s = (jshort)ival;
         break;
@@ -2035,11 +2037,11 @@
     }
   }
 
-  assert(sig_type != '[', "array should have sig_type == 'L'");
+  assert(sig_type != JVM_SIGNATURE_ARRAY, "array should have sig_type == 'L'");
   bool handle_created = false;
 
   // convert oop to JNI handle.
-  if (sig_type == 'L') {
+  if (sig_type == JVM_SIGNATURE_CLASS) {
     handle_created = true;
     value->l = (jobject)JNIHandles::make_local(thread, (oop)value->l);
   }
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/prims/jvmtiImpl.cpp
--- a/src/hotspot/share/prims/jvmtiImpl.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/prims/jvmtiImpl.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -588,7 +588,8 @@
   assert(klass != NULL, "klass must not be NULL");
 
   int len = (int) strlen(ty_sign);
-  if (ty_sign[0] == 'L' && ty_sign[len-1] == ';') { // Need pure class/interface name
+  if (ty_sign[0] == JVM_SIGNATURE_CLASS &&
+      ty_sign[len-1] == JVM_SIGNATURE_ENDCLASS) { // Need pure class/interface name
     ty_sign++;
     len -= 2;
   }
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/prims/jvmtiRedefineClasses.cpp
--- a/src/hotspot/share/prims/jvmtiRedefineClasses.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/prims/jvmtiRedefineClasses.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -2166,14 +2166,14 @@
 
   switch (tag) {
     // These BaseType tag values are from Table 4.2 in VM spec:
-    case 'B':  // byte
-    case 'C':  // char
-    case 'D':  // double
-    case 'F':  // float
-    case 'I':  // int
-    case 'J':  // long
-    case 'S':  // short
-    case 'Z':  // boolean
+    case JVM_SIGNATURE_BYTE:
+    case JVM_SIGNATURE_CHAR:
+    case JVM_SIGNATURE_DOUBLE:
+    case JVM_SIGNATURE_FLOAT:
+    case JVM_SIGNATURE_INT:
+    case JVM_SIGNATURE_LONG:
+    case JVM_SIGNATURE_SHORT:
+    case JVM_SIGNATURE_BOOLEAN:
 
     // The remaining tag values are from Table 4.8 in the 2nd-edition of
     // the VM spec:
@@ -2244,7 +2244,7 @@
       }
       break;
 
-    case '[':
+    case JVM_SIGNATURE_ARRAY:
     {
       if ((byte_i_ref + 2) > annotations_typeArray->length()) {
         // not enough room for a num_values field
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/prims/jvmtiTagMap.cpp
--- a/src/hotspot/share/prims/jvmtiTagMap.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/prims/jvmtiTagMap.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -1032,7 +1032,7 @@
 
 // helper function to tell if a field is a primitive field or not
 static inline bool is_primitive_field_type(char type) {
-  return (type != 'L' && type != '[');
+  return (type != JVM_SIGNATURE_CLASS && type != JVM_SIGNATURE_ARRAY);
 }
 
 // helper function to copy the value from location addr to jvalue.
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/prims/methodHandles.cpp
--- a/src/hotspot/share/prims/methodHandles.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/prims/methodHandles.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -542,18 +542,22 @@
   const int len = sig->utf8_length();
   for (int i = 0; i < len; i++) {
     switch (sig->char_at(i)) {
-    case 'L':
+    case JVM_SIGNATURE_CLASS:
       // only java/lang/Object is valid here
       if (sig->index_of_at(i, OBJ_SIG, OBJ_SIG_LEN) != i)
         return false;
       i += OBJ_SIG_LEN-1;  //-1 because of i++ in loop
       continue;
-    case '(': case ')': case 'V':
-    case 'I': case 'J': case 'F': case 'D':
+    case JVM_SIGNATURE_FUNC:
+    case JVM_SIGNATURE_ENDFUNC:
+    case JVM_SIGNATURE_VOID:
+    case JVM_SIGNATURE_INT:
+    case JVM_SIGNATURE_LONG:
+    case JVM_SIGNATURE_FLOAT:
+    case JVM_SIGNATURE_DOUBLE:
       continue;
-    //case '[':
-    //case 'Z': case 'B': case 'C': case 'S':
     default:
+      // subword types (T_BYTE etc.), arrays
       return false;
     }
   }
@@ -567,7 +571,7 @@
   } else if (is_basic_type_signature(sig)) {
     sig->increment_refcount();
     return sig;  // that was easy
-  } else if (sig->char_at(0) != '(') {
+  } else if (sig->char_at(0) != JVM_SIGNATURE_FUNC) {
     BasicType bt = char2type(sig->char_at(0));
     if (is_subword_type(bt)) {
       bsig = vmSymbols::int_signature();
@@ -578,7 +582,7 @@
   } else {
     ResourceMark rm;
     stringStream buffer(128);
-    buffer.put('(');
+    buffer.put(JVM_SIGNATURE_FUNC);
     int arg_pos = 0, keep_arg_pos = -1;
     if (keep_last_arg)
       keep_arg_pos = ArgumentCount(sig).size() - 1;
@@ -586,7 +590,7 @@
       BasicType bt = ss.type();
       size_t this_arg_pos = buffer.size();
       if (ss.at_return_type()) {
-        buffer.put(')');
+        buffer.put(JVM_SIGNATURE_ENDFUNC);
       }
       if (arg_pos == keep_arg_pos) {
         buffer.write((char*) ss.raw_bytes(),
@@ -621,25 +625,26 @@
   for (int i = 0; i < len; i++) {
     char ch = sig->char_at(i);
     switch (ch) {
-    case '(': case ')':
+    case JVM_SIGNATURE_FUNC:
+    case JVM_SIGNATURE_ENDFUNC:
       prev_type = false;
       st->put(ch);
       continue;
-    case '[':
+    case JVM_SIGNATURE_ARRAY:
       if (!keep_basic_names && keep_arrays)
         st->put(ch);
       array++;
       continue;
-    case 'L':
+    case JVM_SIGNATURE_CLASS:
       {
         if (prev_type)  st->put(',');
         int start = i+1, slash = start;
-        while (++i < len && (ch = sig->char_at(i)) != ';') {
-          if (ch == '/' || ch == '.' || ch == '$')  slash = i+1;
+        while (++i < len && (ch = sig->char_at(i)) != JVM_SIGNATURE_ENDCLASS) {
+          if (ch == JVM_SIGNATURE_SLASH || ch == JVM_SIGNATURE_DOT || ch == '$')  slash = i+1;
         }
         if (slash < i)  start = slash;
         if (!keep_basic_names) {
-          st->put('L');
+          st->put(JVM_SIGNATURE_CLASS);
         } else {
           for (int j = start; j < i; j++)
             st->put(sig->char_at(j));
@@ -650,7 +655,7 @@
     default:
       {
         if (array && char2type(ch) != T_ILLEGAL && !keep_arrays) {
-          ch = '[';
+          ch = JVM_SIGNATURE_ARRAY;
           array = 0;
         }
         if (prev_type)  st->put(',');
@@ -978,7 +983,7 @@
   }
   if (sig != NULL) {
     if (sig->utf8_length() == 0)  return 0; // a match is not possible
-    if (sig->char_at(0) == '(')
+    if (sig->char_at(0) == JVM_SIGNATURE_FUNC)
       match_flags &= ~(IS_FIELD | IS_TYPE);
     else
       match_flags &= ~(IS_CONSTRUCTOR | IS_METHOD);
@@ -1456,7 +1461,7 @@
           {
             Symbol* type = caller->constants()->signature_ref_at(bss_index_in_pool);
             Handle th;
-            if (type->char_at(0) == '(') {
+            if (type->char_at(0) == JVM_SIGNATURE_FUNC) {
               th = SystemDictionary::find_method_handle_type(type, caller, CHECK);
             } else {
               th = SystemDictionary::find_java_mirror_for_type(type, caller, SignatureStream::NCDFError, CHECK);
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/prims/nativeLookup.cpp
--- a/src/hotspot/share/prims/nativeLookup.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/prims/nativeLookup.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -106,7 +106,7 @@
   st.print("__");
   // find ')'
   int end;
-  for (end = 0; end < signature->utf8_length() && signature->char_at(end) != ')'; end++);
+  for (end = 0; end < signature->utf8_length() && signature->char_at(end) != JVM_SIGNATURE_ENDFUNC; end++);
   // skip first '('
   mangle_name_on(&st, signature, 1, end);
   return st.as_string();
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/runtime/fieldType.cpp
--- a/src/hotspot/share/runtime/fieldType.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/runtime/fieldType.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -39,28 +39,28 @@
 // Check if it is a valid array signature
 bool FieldType::is_valid_array_signature(Symbol* sig) {
   assert(sig->utf8_length() > 1, "this should already have been checked");
-  assert(sig->char_at(0) == '[', "this should already have been checked");
+  assert(sig->char_at(0) == JVM_SIGNATURE_ARRAY, "this should already have been checked");
   // The first character is already checked
   int i = 1;
   int len = sig->utf8_length();
   // First skip all '['s
-  while(i < len - 1 && sig->char_at(i) == '[') i++;
+  while(i < len - 1 && sig->char_at(i) == JVM_SIGNATURE_ARRAY) i++;
 
   // Check type
   switch(sig->char_at(i)) {
-    case 'B': // T_BYTE
-    case 'C': // T_CHAR
-    case 'D': // T_DOUBLE
-    case 'F': // T_FLOAT
-    case 'I': // T_INT
-    case 'J': // T_LONG
-    case 'S': // T_SHORT
-    case 'Z': // T_BOOLEAN
+    case JVM_SIGNATURE_BYTE:
+    case JVM_SIGNATURE_CHAR:
+    case JVM_SIGNATURE_DOUBLE:
+    case JVM_SIGNATURE_FLOAT:
+    case JVM_SIGNATURE_INT:
+    case JVM_SIGNATURE_LONG:
+    case JVM_SIGNATURE_SHORT:
+    case JVM_SIGNATURE_BOOLEAN:
       // If it is an array, the type is the last character
       return (i + 1 == len);
-    case 'L':
+    case JVM_SIGNATURE_CLASS:
       // If it is an object, the last character must be a ';'
-      return sig->char_at(len - 1) == ';';
+      return sig->char_at(len - 1) == JVM_SIGNATURE_ENDCLASS;
   }
 
   return false;
@@ -71,7 +71,7 @@
   assert(basic_type(signature) == T_ARRAY, "must be array");
   int index = 1;
   int dim   = 1;
-  while (signature->char_at(index) == '[') {
+  while (signature->char_at(index) == JVM_SIGNATURE_ARRAY) {
     index++;
     dim++;
   }
@@ -80,7 +80,7 @@
   BasicType element_type = char2type(element[0]);
   if (element_type == T_OBJECT) {
     int len = (int)strlen(element);
-    assert(element[len-1] == ';', "last char should be a semicolon");
+    assert(element[len-1] == JVM_SIGNATURE_ENDCLASS, "last char should be a semicolon");
     element[len-1] = '\0';        // chop off semicolon
     fd._object_key = SymbolTable::new_symbol(element + 1);
   }
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/runtime/fieldType.hpp
--- a/src/hotspot/share/runtime/fieldType.hpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/runtime/fieldType.hpp	Mon Oct 21 13:13:16 2019 -0400
@@ -58,14 +58,16 @@
   static BasicType basic_type(Symbol* signature);
 
   // Testing
-  static bool is_array(Symbol* signature) { return signature->utf8_length() > 1 && signature->char_at(0) == '[' && is_valid_array_signature(signature); }
+  static bool is_array(Symbol* signature) { return signature->utf8_length() > 1 &&
+                                                   signature->char_at(0) == JVM_SIGNATURE_ARRAY &&
+                                                   is_valid_array_signature(signature); }
 
   static bool is_obj(Symbol* signature) {
      int sig_length = signature->utf8_length();
      // Must start with 'L' and end with ';'
      return (sig_length >= 2 &&
-             (signature->char_at(0) == 'L') &&
-             (signature->char_at(sig_length - 1) == ';'));
+             (signature->char_at(0) == JVM_SIGNATURE_CLASS) &&
+             (signature->char_at(sig_length - 1) == JVM_SIGNATURE_ENDCLASS));
   }
 
   // Parse field and extract array information. Works for T_ARRAY only.
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/runtime/sharedRuntime.cpp
--- a/src/hotspot/share/runtime/sharedRuntime.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/runtime/sharedRuntime.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -2990,28 +2990,28 @@
     sig_bt[cnt++] = T_OBJECT; // Receiver is argument 0; not in signature
   }
 
-  while (*s != ')') {          // Find closing right paren
-    switch (*s++) {            // Switch on signature character
-    case 'B': sig_bt[cnt++] = T_BYTE;    break;
-    case 'C': sig_bt[cnt++] = T_CHAR;    break;
-    case 'D': sig_bt[cnt++] = T_DOUBLE;  sig_bt[cnt++] = T_VOID; break;
-    case 'F': sig_bt[cnt++] = T_FLOAT;   break;
-    case 'I': sig_bt[cnt++] = T_INT;     break;
-    case 'J': sig_bt[cnt++] = T_LONG;    sig_bt[cnt++] = T_VOID; break;
-    case 'S': sig_bt[cnt++] = T_SHORT;   break;
-    case 'Z': sig_bt[cnt++] = T_BOOLEAN; break;
-    case 'V': sig_bt[cnt++] = T_VOID;    break;
-    case 'L':                   // Oop
-      while (*s++ != ';');   // Skip signature
+  while (*s != JVM_SIGNATURE_ENDFUNC) { // Find closing right paren
+    switch (*s++) {                     // Switch on signature character
+    case JVM_SIGNATURE_BYTE:    sig_bt[cnt++] = T_BYTE;    break;
+    case JVM_SIGNATURE_CHAR:    sig_bt[cnt++] = T_CHAR;    break;
+    case JVM_SIGNATURE_DOUBLE:  sig_bt[cnt++] = T_DOUBLE;  sig_bt[cnt++] = T_VOID; break;
+    case JVM_SIGNATURE_FLOAT:   sig_bt[cnt++] = T_FLOAT;   break;
+    case JVM_SIGNATURE_INT:     sig_bt[cnt++] = T_INT;     break;
+    case JVM_SIGNATURE_LONG:    sig_bt[cnt++] = T_LONG;    sig_bt[cnt++] = T_VOID; break;
+    case JVM_SIGNATURE_SHORT:   sig_bt[cnt++] = T_SHORT;   break;
+    case JVM_SIGNATURE_BOOLEAN: sig_bt[cnt++] = T_BOOLEAN; break;
+    case JVM_SIGNATURE_VOID:    sig_bt[cnt++] = T_VOID;    break;
+    case JVM_SIGNATURE_CLASS: // Oop
+      while (*s++ != JVM_SIGNATURE_ENDCLASS);   // Skip signature
       sig_bt[cnt++] = T_OBJECT;
       break;
-    case '[': {                 // Array
+    case JVM_SIGNATURE_ARRAY: { // Array
       do {                      // Skip optional size
         while (*s >= '0' && *s <= '9') s++;
-      } while (*s++ == '[');   // Nested arrays?
+      } while (*s++ == JVM_SIGNATURE_ARRAY);   // Nested arrays?
       // Skip element type
-      if (s[-1] == 'L')
-        while (*s++ != ';'); // Skip signature
+      if (s[-1] == JVM_SIGNATURE_CLASS)
+        while (*s++ != JVM_SIGNATURE_ENDCLASS); // Skip signature
       sig_bt[cnt++] = T_ARRAY;
       break;
     }
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/runtime/signature.cpp
--- a/src/hotspot/share/runtime/signature.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/runtime/signature.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -63,41 +63,41 @@
   //       compiler bug (was problem - gri 4/27/2000).
   int size = -1;
   switch(_signature->char_at(_index)) {
-    case 'B': do_byte  (); if (_parameter_index < 0 ) _return_type = T_BYTE;
-              _index++; size = T_BYTE_size   ; break;
-    case 'C': do_char  (); if (_parameter_index < 0 ) _return_type = T_CHAR;
-              _index++; size = T_CHAR_size   ; break;
-    case 'D': do_double(); if (_parameter_index < 0 ) _return_type = T_DOUBLE;
-              _index++; size = T_DOUBLE_size ; break;
-    case 'F': do_float (); if (_parameter_index < 0 ) _return_type = T_FLOAT;
-              _index++; size = T_FLOAT_size  ; break;
-    case 'I': do_int   (); if (_parameter_index < 0 ) _return_type = T_INT;
-              _index++; size = T_INT_size    ; break;
-    case 'J': do_long  (); if (_parameter_index < 0 ) _return_type = T_LONG;
-              _index++; size = T_LONG_size   ; break;
-    case 'S': do_short (); if (_parameter_index < 0 ) _return_type = T_SHORT;
-              _index++; size = T_SHORT_size  ; break;
-    case 'Z': do_bool  (); if (_parameter_index < 0 ) _return_type = T_BOOLEAN;
-              _index++; size = T_BOOLEAN_size; break;
-    case 'V': do_void  (); if (_parameter_index < 0 ) _return_type = T_VOID;
-              _index++; size = T_VOID_size;  ; break;
-    case 'L':
+    case JVM_SIGNATURE_BYTE:    do_byte(); if (_parameter_index < 0 ) _return_type = T_BYTE;
+                                  _index++; size = T_BYTE_size; break;
+    case JVM_SIGNATURE_CHAR:    do_char(); if (_parameter_index < 0 ) _return_type = T_CHAR;
+                                  _index++; size = T_CHAR_size; break;
+    case JVM_SIGNATURE_DOUBLE:  do_double(); if (_parameter_index < 0 ) _return_type = T_DOUBLE;
+                                  _index++; size = T_DOUBLE_size; break;
+    case JVM_SIGNATURE_FLOAT:   do_float(); if (_parameter_index < 0 ) _return_type = T_FLOAT;
+                                  _index++; size = T_FLOAT_size; break;
+    case JVM_SIGNATURE_INT:     do_int(); if (_parameter_index < 0 ) _return_type = T_INT;
+                                  _index++; size = T_INT_size; break;
+    case JVM_SIGNATURE_LONG:    do_long(); if (_parameter_index < 0 ) _return_type = T_LONG;
+                                  _index++; size = T_LONG_size; break;
+    case JVM_SIGNATURE_SHORT:   do_short(); if (_parameter_index < 0 ) _return_type = T_SHORT;
+                                  _index++; size = T_SHORT_size; break;
+    case JVM_SIGNATURE_BOOLEAN: do_bool(); if (_parameter_index < 0 ) _return_type = T_BOOLEAN;
+                                  _index++; size = T_BOOLEAN_size; break;
+    case JVM_SIGNATURE_VOID:    do_void(); if (_parameter_index < 0 ) _return_type = T_VOID;
+                                  _index++; size = T_VOID_size; break;
+    case JVM_SIGNATURE_CLASS:
       { int begin = ++_index;
         Symbol* sig = _signature;
-        while (sig->char_at(_index++) != ';') ;
+        while (sig->char_at(_index++) != JVM_SIGNATURE_ENDCLASS) ;
         do_object(begin, _index);
       }
       if (_parameter_index < 0 ) _return_type = T_OBJECT;
       size = T_OBJECT_size;
       break;
-    case '[':
+    case JVM_SIGNATURE_ARRAY:
       { int begin = ++_index;
         Symbol* sig = _signature;
-        while (sig->char_at(_index) == '[') {
+        while (sig->char_at(_index) == JVM_SIGNATURE_ARRAY) {
           _index++;
         }
-        if (sig->char_at(_index) == 'L') {
-          while (sig->char_at(_index++) != ';') ;
+        if (sig->char_at(_index) == JVM_SIGNATURE_CLASS) {
+          while (sig->char_at(_index++) != JVM_SIGNATURE_ENDCLASS) ;
         } else {
           _index++;
         }
@@ -128,9 +128,9 @@
   // Parse parameters
   _index = 0;
   _parameter_index = 0;
-  expect('(');
-  while (_signature->char_at(_index) != ')') _parameter_index += parse_type();
-  expect(')');
+  expect(JVM_SIGNATURE_FUNC);
+  while (_signature->char_at(_index) != JVM_SIGNATURE_ENDFUNC) _parameter_index += parse_type();
+  expect(JVM_SIGNATURE_ENDFUNC);
   _parameter_index = 0;
 }
 
@@ -202,36 +202,36 @@
 void SignatureIterator::iterate_returntype() {
   // Ignore parameters
   _index = 0;
-  expect('(');
+  expect(JVM_SIGNATURE_FUNC);
   Symbol* sig = _signature;
   // Need to skip over each type in the signature's argument list until a
   // closing ')' is found., then get the return type.  We cannot just scan
   // for the first ')' because ')' is a legal character in a type name.
-  while (sig->char_at(_index) != ')') {
+  while (sig->char_at(_index) != JVM_SIGNATURE_ENDFUNC) {
     switch(sig->char_at(_index)) {
-      case 'B':
-      case 'C':
-      case 'D':
-      case 'F':
-      case 'I':
-      case 'J':
-      case 'S':
-      case 'Z':
-      case 'V':
+      case JVM_SIGNATURE_BYTE:
+      case JVM_SIGNATURE_CHAR:
+      case JVM_SIGNATURE_DOUBLE:
+      case JVM_SIGNATURE_FLOAT:
+      case JVM_SIGNATURE_INT:
+      case JVM_SIGNATURE_LONG:
+      case JVM_SIGNATURE_SHORT:
+      case JVM_SIGNATURE_BOOLEAN:
+      case JVM_SIGNATURE_VOID:
         {
           _index++;
         }
         break;
-      case 'L':
+      case JVM_SIGNATURE_CLASS:
         {
-          while (sig->char_at(_index++) != ';') ;
+          while (sig->char_at(_index++) != JVM_SIGNATURE_ENDCLASS) ;
         }
         break;
-      case '[':
+      case JVM_SIGNATURE_ARRAY:
         {
-          while (sig->char_at(++_index) == '[') ;
-          if (sig->char_at(_index) == 'L') {
-            while (sig->char_at(_index++) != ';') ;
+          while (sig->char_at(++_index) == JVM_SIGNATURE_ARRAY) ;
+          if (sig->char_at(_index) == JVM_SIGNATURE_CLASS) {
+            while (sig->char_at(_index++) != JVM_SIGNATURE_ENDCLASS) ;
           } else {
             _index++;
           }
@@ -242,7 +242,7 @@
         break;
     }
   }
-  expect(')');
+  expect(JVM_SIGNATURE_ENDFUNC);
   // Parse return type
   _parameter_index = -1;
   parse_type();
@@ -255,9 +255,9 @@
   // Parse parameters
   _parameter_index = 0;
   _index = 0;
-  expect('(');
-  while (_signature->char_at(_index) != ')') _parameter_index += parse_type();
-  expect(')');
+  expect(JVM_SIGNATURE_FUNC);
+  while (_signature->char_at(_index) != JVM_SIGNATURE_ENDFUNC) _parameter_index += parse_type();
+  expect(JVM_SIGNATURE_ENDFUNC);
   // Parse return type
   _parameter_index = -1;
   parse_type();
@@ -289,39 +289,39 @@
 
 void SignatureStream::next_non_primitive(int t) {
   switch (t) {
-    case 'L': {
+    case JVM_SIGNATURE_CLASS: {
       _type = T_OBJECT;
       Symbol* sig = _signature;
-      while (sig->char_at(_end++) != ';');
+      while (sig->char_at(_end++) != JVM_SIGNATURE_ENDCLASS);
       break;
     }
-    case '[': {
+    case JVM_SIGNATURE_ARRAY: {
       _type = T_ARRAY;
       Symbol* sig = _signature;
       char c = sig->char_at(_end);
       while ('0' <= c && c <= '9') c = sig->char_at(_end++);
-      while (sig->char_at(_end) == '[') {
+      while (sig->char_at(_end) == JVM_SIGNATURE_ARRAY) {
         _end++;
         c = sig->char_at(_end);
         while ('0' <= c && c <= '9') c = sig->char_at(_end++);
       }
       switch(sig->char_at(_end)) {
-        case 'B':
-        case 'C':
-        case 'D':
-        case 'F':
-        case 'I':
-        case 'J':
-        case 'S':
-        case 'Z':_end++; break;
+        case JVM_SIGNATURE_BYTE:
+        case JVM_SIGNATURE_CHAR:
+        case JVM_SIGNATURE_DOUBLE:
+        case JVM_SIGNATURE_FLOAT:
+        case JVM_SIGNATURE_INT:
+        case JVM_SIGNATURE_LONG:
+        case JVM_SIGNATURE_SHORT:
+        case JVM_SIGNATURE_BOOLEAN:_end++; break;
         default: {
-          while (sig->char_at(_end++) != ';');
+          while (sig->char_at(_end++) != JVM_SIGNATURE_ENDCLASS);
           break;
         }
       }
       break;
     }
-    case ')': _end++; next(); _at_return_type = true; break;
+    case JVM_SIGNATURE_ENDFUNC: _end++; next(); _at_return_type = true; break;
     default : ShouldNotReachHere();
   }
 }
@@ -341,8 +341,8 @@
   int begin = _begin;
   int end   = _end;
 
-  if (   _signature->char_at(_begin) == 'L'
-      && _signature->char_at(_end-1) == ';') {
+  if (   _signature->char_at(_begin) == JVM_SIGNATURE_CLASS
+      && _signature->char_at(_end-1) == JVM_SIGNATURE_ENDCLASS) {
     begin++;
     end--;
   }
@@ -407,8 +407,8 @@
   int begin = _begin;
   int end   = _end;
 
-  if (   _signature->char_at(_begin) == 'L'
-      && _signature->char_at(_end-1) == ';') {
+  if (   _signature->char_at(_begin) == JVM_SIGNATURE_CLASS
+      && _signature->char_at(_end-1) == JVM_SIGNATURE_ENDCLASS) {
     begin++;
     end--;
   }
@@ -436,9 +436,9 @@
   const char* method_sig = (const char*)sig->bytes();
   ssize_t len = sig->utf8_length();
   ssize_t index = 0;
-  if (method_sig != NULL && len > 1 && method_sig[index] == '(') {
+  if (method_sig != NULL && len > 1 && method_sig[index] == JVM_SIGNATURE_FUNC) {
     ++index;
-    while (index < len && method_sig[index] != ')') {
+    while (index < len && method_sig[index] != JVM_SIGNATURE_ENDFUNC) {
       ssize_t res = is_valid_type(&method_sig[index], len - index);
       if (res == -1) {
         return false;
@@ -446,7 +446,7 @@
         index += res;
       }
     }
-    if (index < len && method_sig[index] == ')') {
+    if (index < len && method_sig[index] == JVM_SIGNATURE_ENDFUNC) {
       // check the return type
       ++index;
       return (is_valid_type(&method_sig[index], len - index) == (len - index));
@@ -469,21 +469,28 @@
   ssize_t index = 0;
 
   // Iterate over any number of array dimensions
-  while (index < limit && type[index] == '[') ++index;
+  while (index < limit && type[index] == JVM_SIGNATURE_ARRAY) ++index;
   if (index >= limit) {
     return -1;
   }
   switch (type[index]) {
-    case 'B': case 'C': case 'D': case 'F': case 'I':
-    case 'J': case 'S': case 'Z': case 'V':
+    case JVM_SIGNATURE_BYTE:
+    case JVM_SIGNATURE_CHAR:
+    case JVM_SIGNATURE_DOUBLE:
+    case JVM_SIGNATURE_FLOAT:
+    case JVM_SIGNATURE_INT:
+    case JVM_SIGNATURE_LONG:
+    case JVM_SIGNATURE_SHORT:
+    case JVM_SIGNATURE_BOOLEAN:
+    case JVM_SIGNATURE_VOID:
       return index + 1;
-    case 'L':
+    case JVM_SIGNATURE_CLASS:
       for (index = index + 1; index < limit; ++index) {
         char c = type[index];
         switch (c) {
-          case ';':
+          case JVM_SIGNATURE_ENDCLASS:
             return index + 1;
-          case '\0': case '.': case '[':
+          case '\0': case JVM_SIGNATURE_DOT: case JVM_SIGNATURE_ARRAY:
             return -1;
           default: ; // fall through
         }
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/runtime/signature.hpp
--- a/src/hotspot/share/runtime/signature.hpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/runtime/signature.hpp	Mon Oct 21 13:13:16 2019 -0400
@@ -379,15 +379,15 @@
     _begin = _end;
     int t = sig->char_at(_begin);
     switch (t) {
-      case 'B': _type = T_BYTE;    break;
-      case 'C': _type = T_CHAR;    break;
-      case 'D': _type = T_DOUBLE;  break;
-      case 'F': _type = T_FLOAT;   break;
-      case 'I': _type = T_INT;     break;
-      case 'J': _type = T_LONG;    break;
-      case 'S': _type = T_SHORT;   break;
-      case 'Z': _type = T_BOOLEAN; break;
-      case 'V': _type = T_VOID;    break;
+      case JVM_SIGNATURE_BYTE:    _type = T_BYTE;    break;
+      case JVM_SIGNATURE_CHAR:    _type = T_CHAR;    break;
+      case JVM_SIGNATURE_DOUBLE:  _type = T_DOUBLE;  break;
+      case JVM_SIGNATURE_FLOAT:   _type = T_FLOAT;   break;
+      case JVM_SIGNATURE_INT:     _type = T_INT;     break;
+      case JVM_SIGNATURE_LONG:    _type = T_LONG;    break;
+      case JVM_SIGNATURE_SHORT:   _type = T_SHORT;   break;
+      case JVM_SIGNATURE_BOOLEAN: _type = T_BOOLEAN; break;
+      case JVM_SIGNATURE_VOID:    _type = T_VOID;    break;
       default : next_non_primitive(t);
                 return;
     }
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/utilities/globalDefinitions.cpp
--- a/src/hotspot/share/utilities/globalDefinitions.cpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/utilities/globalDefinitions.cpp	Mon Oct 21 13:13:16 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -178,7 +178,16 @@
 
 
 // Map BasicType to signature character
-char type2char_tab[T_CONFLICT+1]={ 0, 0, 0, 0, 'Z', 'C', 'F', 'D', 'B', 'S', 'I', 'J', 'L', '[', 'V', 0, 0, 0, 0, 0};
+char type2char_tab[T_CONFLICT+1] = {
+  0, 0, 0, 0,
+  JVM_SIGNATURE_BOOLEAN, JVM_SIGNATURE_CHAR,
+  JVM_SIGNATURE_FLOAT,   JVM_SIGNATURE_DOUBLE,
+  JVM_SIGNATURE_BYTE,    JVM_SIGNATURE_SHORT,
+  JVM_SIGNATURE_INT,     JVM_SIGNATURE_LONG,
+  JVM_SIGNATURE_CLASS,   JVM_SIGNATURE_ARRAY,
+  JVM_SIGNATURE_VOID,    0,
+  0, 0, 0, 0
+};
 
 // Map BasicType to Java type name
 const char* type2name_tab[T_CONFLICT+1] = {
diff -r ae0af9fb3dbb -r cba8afa5cfed src/hotspot/share/utilities/globalDefinitions.hpp
--- a/src/hotspot/share/utilities/globalDefinitions.hpp	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/hotspot/share/utilities/globalDefinitions.hpp	Mon Oct 21 13:13:16 2019 -0400
@@ -29,6 +29,9 @@
 #include "utilities/debug.hpp"
 #include "utilities/macros.hpp"
 
+// Get constants like JVM_T_CHAR and JVM_SIGNATURE_INT, before pulling in <jvm.h>.
+#include "classfile_constants.h"
+
 #include COMPILER_HEADER(utilities/globalDefinitions)
 
 // Defaults for macros that might be defined per compiler.
@@ -570,14 +573,22 @@
 
 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
 enum BasicType {
-  T_BOOLEAN     =  4,
-  T_CHAR        =  5,
-  T_FLOAT       =  6,
-  T_DOUBLE      =  7,
-  T_BYTE        =  8,
-  T_SHORT       =  9,
-  T_INT         = 10,
-  T_LONG        = 11,
+// The values T_BOOLEAN..T_LONG (4..11) are derived from the JVMS.
+  T_BOOLEAN     = JVM_T_BOOLEAN,
+  T_CHAR        = JVM_T_CHAR,
+  T_FLOAT       = JVM_T_FLOAT,
+  T_DOUBLE      = JVM_T_DOUBLE,
+  T_BYTE        = JVM_T_BYTE,
+  T_SHORT       = JVM_T_SHORT,
+  T_INT         = JVM_T_INT,
+  T_LONG        = JVM_T_LONG,
+  // The remaining values are not part of any standard.
+  // T_OBJECT and T_VOID denote two more semantic choices
+  // for method return values.
+  // T_OBJECT and T_ARRAY describe signature syntax.
+  // T_ADDRESS, T_METADATA, T_NARROWOOP, T_NARROWKLASS describe
+  // internal references within the JVM as if they were Java
+  // types in their own right.
   T_OBJECT      = 12,
   T_ARRAY       = 13,
   T_VOID        = 14,
@@ -602,6 +613,10 @@
   return (t == T_BYTE || t == T_SHORT);
 }
 
+inline bool is_double_word_type(BasicType t) {
+  return (t == T_DOUBLE || t == T_LONG);
+}
+
 inline bool is_reference_type(BasicType t) {
   return (t == T_OBJECT || t == T_ARRAY);
 }
@@ -609,17 +624,17 @@
 // Convert a char from a classfile signature to a BasicType
 inline BasicType char2type(char c) {
   switch( c ) {
-  case 'B': return T_BYTE;
-  case 'C': return T_CHAR;
-  case 'D': return T_DOUBLE;
-  case 'F': return T_FLOAT;
-  case 'I': return T_INT;
-  case 'J': return T_LONG;
-  case 'S': return T_SHORT;
-  case 'Z': return T_BOOLEAN;
-  case 'V': return T_VOID;
-  case 'L': return T_OBJECT;
-  case '[': return T_ARRAY;
+  case JVM_SIGNATURE_BYTE:    return T_BYTE;
+  case JVM_SIGNATURE_CHAR:    return T_CHAR;
+  case JVM_SIGNATURE_DOUBLE:  return T_DOUBLE;
+  case JVM_SIGNATURE_FLOAT:   return T_FLOAT;
+  case JVM_SIGNATURE_INT:     return T_INT;
+  case JVM_SIGNATURE_LONG:    return T_LONG;
+  case JVM_SIGNATURE_SHORT:   return T_SHORT;
+  case JVM_SIGNATURE_BOOLEAN: return T_BOOLEAN;
+  case JVM_SIGNATURE_VOID:    return T_VOID;
+  case JVM_SIGNATURE_CLASS:   return T_OBJECT;
+  case JVM_SIGNATURE_ARRAY:   return T_ARRAY;
   }
   return T_ILLEGAL;
 }
diff -r ae0af9fb3dbb -r cba8afa5cfed src/java.base/share/native/include/classfile_constants.h.template
--- a/src/java.base/share/native/include/classfile_constants.h.template	Mon Oct 21 09:26:14 2019 -0700
+++ b/src/java.base/share/native/include/classfile_constants.h.template	Mon Oct 21 13:13:16 2019 -0400
@@ -144,6 +144,10 @@
 /* Type signatures */
 
 enum {
+    JVM_SIGNATURE_SLASH         = '/',
+    JVM_SIGNATURE_DOT           = '.',
+    JVM_SIGNATURE_SPECIAL       = '<',
+    JVM_SIGNATURE_ENDSPECIAL    = '>',
     JVM_SIGNATURE_ARRAY         = '[',
     JVM_SIGNATURE_BYTE          = 'B',
     JVM_SIGNATURE_CHAR          = 'C',