jcf-reader: support for JSR 292 classfile extensions

Andrew Haley aph@redhat.com
Wed Apr 11 10:22:00 GMT 2012


This adds support for the new (Version 51.0) class file format.  It
doesn't actually generate code for invokedynamic bcause we don't have
any runtime support yet, but it's a start.  jcf-dump prints all of the
new attributes.

Andrew.


2012-04-11  Andrew Haley  <aph@redhat.com>

	* jcf.h (bootstrap_method): New.
	(BootstrapMethods): New.
	(JCF): Add BootstrapMethods.
	(enum cpool_tag): Add MethodHandle, MethodType, and InvokeDynamic.
	* jcf-reader.c (jcf_parse_bootstrap_methods): New.
	(jcf_parse_constant_pool): Handlers for MethodHandle, MethodType,
	and InvokeDynamic.
	(jcf_parse_bootstrap_methods): New.
	* javaop.def (invokedynamic): New opcode.
	* jcf-parse.c (get_constant): An unknown constant type should not
	be an internal error, but a fatal one.  Make it so.
	* jcf-dump.c (HANDLE_BOOTSTRAP_METHODS_ATTRIBUTE): New.
	(HANDLE_END_BOOTSTRAP_METHODS): New.
	(print_constant): Handlers for MethodHandle, MethodType, and
	InvokeDynamic.

Index: java/jcf-dump.c
===================================================================
--- java/jcf-dump.c	(revision 186103)
+++ java/jcf-dump.c	(working copy)
@@ -430,7 +430,24 @@
   print_element_value (out, jcf, 1);					\
 }

+#define HANDLE_BOOTSTRAP_METHODS_ATTRIBUTE()				\
+{									\
+  COMMON_HANDLE_ATTRIBUTE(jcf, attribute_name, attribute_length);	\
+  fputc ('\n', out); jcf_parse_bootstrap_methods (jcf, attribute_length); \
+}

+#define HANDLE_END_BOOTSTRAP_METHODS(NUM_METHODS)			\
+  {									\
+    int i;								\
+    for (i = 0; i < NUM_METHODS; i++)					\
+      {									\
+	bootstrap_method *m = &jcf->bootstrap_methods.methods[i];	\
+	fprintf (out, "  %d: ", i);					\
+	print_constant (out, jcf, m->method_ref, 1);			\
+	fprintf (out, "\n");						\
+      }									\
+  }
+
 #define PROCESS_OTHER_ATTRIBUTE(JCF, INDEX, LENGTH) \
 { COMMON_HANDLE_ATTRIBUTE(JCF, INDEX, LENGTH); \
   fputc ('\n', out); JCF_SKIP (JCF, LENGTH); }
@@ -898,6 +915,53 @@
 	fputc ('\"', out);
       }
       break;
+    case CONSTANT_MethodHandle:
+      {
+	int kind = JPOOL_USHORT1 (jcf, index);
+	if (verbosity > 0)
+	  fprintf (out, "MethodHandle kind: %d=", kind);
+	switch(kind) {
+	case 1:
+	case 2:
+	case 3:
+	case 4:
+	  if (verbosity > 0)
+	    fprintf (out, "Fieldref: %ld=", JPOOL_USHORT2 (jcf, index));
+	  print_constant (out, jcf, JPOOL_USHORT2 (jcf, index), 0);
+	case 5:
+	case 6:
+	case 7:
+	case 8:
+	  if (verbosity > 0)
+	    fprintf (out, "Methodref: %ld=", JPOOL_USHORT2 (jcf, index));
+	  print_constant (out, jcf, JPOOL_USHORT2 (jcf, index), 0);
+	  break;
+	case 9:
+	  if (verbosity > 0)
+	    fprintf (out, "InterfaceMethodref: %ld=", JPOOL_USHORT2 (jcf, index));
+	  print_constant (out, jcf, JPOOL_USHORT2 (jcf, index), 0);
+	  break;
+	}
+	break;
+      }
+    case CONSTANT_MethodType:
+      if (verbosity > 0)
+	fprintf (out, "MethodType %ld: ", JPOOL_USHORT1 (jcf, index));
+      print_signature (out, jcf, JPOOL_USHORT1 (jcf, index), 0);
+      break;
+    case CONSTANT_InvokeDynamic:
+      {
+	uint16 name_and_type = JPOOL_USHORT2 (jcf, index);
+	if (verbosity > 0)
+	  fprintf (out, "InvokeDynamic: ");
+	fprintf (out, "bootstrap_method: %ld ", JPOOL_USHORT1 (jcf, index));
+	if (verbosity == 2)
+	  fprintf (out, " name_and_type: %d=<", name_and_type);
+	print_constant_terse (out, jcf, name_and_type, CONSTANT_NameAndType);
+	if (verbosity == 2)
+	  fputc ('>', out);
+	break;
+      }
     default:
       fprintf (out, "(Unknown constant type %d)", kind);
     }
Index: java/jcf-parse.c
===================================================================
--- java/jcf-parse.c	(revision 186103)
+++ java/jcf-parse.c	(working copy)
@@ -1113,8 +1113,8 @@
   jcf->cpool.data[index].t = value;
   return value;
  bad:
-  internal_error ("bad value constant type %d, index %d",
-		  JPOOL_TAG (jcf, index), index);
+  fatal_error ("bad value constant type %d, index %d",
+	       JPOOL_TAG (jcf, index), index);
 }

 tree
Index: java/javaop.def
===================================================================
--- java/javaop.def	(revision 186103)
+++ java/javaop.def	(working copy)
@@ -292,6 +292,7 @@
 JAVAOP (invokespecial, 183, INVOKE,  SPECIAL, 0)
 JAVAOP (invokestatic,  184, INVOKE,  STATIC, 0)
 JAVAOP (invokeinterface,185, INVOKE, INTERFACE, 1)
+JAVAOP (invokedynamic, 186, INVOKE,  DYNAMIC, 1)
 JAVAOP (new,           187, OBJECT,  PTR,    NEW)
 JAVAOP (newarray,      188, ARRAY,   NUM,    NEW)
 JAVAOP (anewarray,     189, ARRAY,   PTR,    NEW)
Index: java/jcf-reader.c
===================================================================
--- java/jcf-reader.c	(revision 186103)
+++ java/jcf-reader.c	(working copy)
@@ -36,6 +36,7 @@
 static int jcf_parse_one_method (JCF *, int);
 static int jcf_parse_methods (JCF *);
 static int jcf_parse_final_attributes (JCF *);
+static int jcf_parse_bootstrap_methods (JCF *, int );
 #ifdef NEED_PEEK_ATTRIBUTE
 static int peek_attribute (JCF *, int, const char *, int);
 #endif
@@ -293,7 +294,16 @@
     }
   else
 #endif
+  if (MATCH_ATTRIBUTE ("BootstrapMethods"))
     {
+#ifdef HANDLE_BOOTSTRAP_METHODS_ATTRIBUTE
+      HANDLE_BOOTSTRAP_METHODS_ATTRIBUTE();
+#else
+      JCF_SKIP (jcf, attribute_length);
+#endif
+    }
+   else
+    {
 #ifdef PROCESS_OTHER_ATTRIBUTE
       PROCESS_OTHER_ATTRIBUTE(jcf, attribute_name, attribute_length);
 #else
@@ -382,6 +392,17 @@
 	  JCF_SKIP (jcf, n);
 #endif
 	  break;
+	case CONSTANT_MethodHandle:
+	  jcf->cpool.data[i].w = JCF_readu (jcf);
+	  jcf->cpool.data[i].w |= JCF_readu2 (jcf) << 16;
+	  break;
+	case CONSTANT_MethodType:
+	  jcf->cpool.data[i].w = JCF_readu2 (jcf);
+	  break;
+	case CONSTANT_InvokeDynamic:
+	  jcf->cpool.data[i].w = JCF_readu2 (jcf);
+	  jcf->cpool.data[i].w |= JCF_readu2 (jcf) << 16;
+	  break;
 	default:
 	  return i;
 	}
@@ -521,3 +542,39 @@
   return 0;
 }

+/* Read and handle the "BootstrapMethods" attribute.
+
+   Return 0 if OK.
+*/
+static int
+jcf_parse_bootstrap_methods (JCF* jcf, int attribute_length ATTRIBUTE_UNUSED)
+{
+  int i;
+  uint16 num_methods = JCF_readu2 (jcf);
+  jcf->bootstrap_methods.count = num_methods;
+  jcf->bootstrap_methods.methods
+    = (bootstrap_method *) ggc_alloc_atomic (num_methods
+					      * sizeof (bootstrap_method));
+#ifdef HANDLE_START_BOOTSTRAP_METHODS
+  HANDLE_START_BOOTSTRAP_METHODS (jcf, num_methods);
+#endif
+
+  for (i = 0; i < num_methods; i++)
+    {
+      unsigned j;
+      bootstrap_method *m = &jcf->bootstrap_methods.methods[i];
+      m->method_ref = JCF_readu2 (jcf);
+      m->num_arguments = JCF_readu2 (jcf);
+      m->bootstrap_arguments
+	= (unsigned *) ggc_alloc_atomic (m->num_arguments
+					 * sizeof (unsigned));
+      for (j = 0; j < m->num_arguments; j++)
+	m->bootstrap_arguments[j] = JCF_readu2 (jcf);
+    }
+
+#ifdef HANDLE_END_BOOTSTRAP_METHODS
+  HANDLE_END_BOOTSTRAP_METHODS (num_methods);
+#endif
+
+  return 0;
+}
Index: java/jcf.h
===================================================================
--- java/jcf.h	(revision 186103)
+++ java/jcf.h	(working copy)
@@ -88,6 +88,17 @@
 			   desc ("cpool_entry_is_tree (%1.tags%a)")))	data;
 } CPool;

+typedef struct GTY(()) bootstrap_method {
+  unsigned method_ref;
+  unsigned num_arguments;
+  unsigned* GTY((length ("%h.num_arguments"))) bootstrap_arguments;
+} bootstrap_method;
+
+typedef struct GTY(()) BootstrapMethods {
+  unsigned count;
+  bootstrap_method* GTY((length ("%h.count"))) methods;
+} BootstrapMethods;
+
 struct ZipDirectory;

 /* JCF encapsulates the state of reading a Java Class File. */
@@ -109,6 +120,7 @@
   JCF_u2 this_class;
   JCF_u2 super_class;
   CPool cpool;
+  BootstrapMethods bootstrap_methods;
 } JCF;
 /*typedef JCF*  JCF_FILE;*/

@@ -245,6 +257,10 @@
   CONSTANT_NameAndType = 12,
   CONSTANT_Utf8 = 1,
   CONSTANT_Unicode = 2,
+  CONSTANT_MethodHandle = 15,
+  CONSTANT_MethodType = 16,
+  CONSTANT_InvokeDynamic = 18,
+
   CONSTANT_None = 0
 };

Index: java/jcf-io.c
===================================================================
--- java/jcf-io.c	(revision 186103)
+++ java/jcf-io.c	(working copy)
@@ -518,6 +518,26 @@
 	case CONSTANT_Utf8:
 	case CONSTANT_Unicode:
 	  break;
+	case CONSTANT_MethodHandle:
+	  n = JPOOL_USHORT1 (jcf, i);
+	  if (n < 1 || n > 9)
+	    return i;
+	  n = JPOOL_USHORT2 (jcf, i);
+	  if (n <= 0 || n >= JPOOL_SIZE(jcf))
+	    return i;
+	  break;
+	case CONSTANT_MethodType:
+	  n = JPOOL_USHORT1 (jcf, i);
+	  if (n <= 0 || n >= JPOOL_SIZE(jcf)
+	      || JPOOL_TAG (jcf, n) != CONSTANT_Utf8)
+	    return i;
+	  break;
+	case CONSTANT_InvokeDynamic:
+	  n = JPOOL_USHORT2 (jcf, i);
+	  if (n <= 0 || n >= JPOOL_SIZE(jcf)
+	      || JPOOL_TAG (jcf, n) != CONSTANT_NameAndType)
+	    return i;
+	  break;
 	default:
 	  return i;
 	}



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