implement instanceof superclass behavior

Makefile

@@ -7,7 +7,7 @@ CC ?= gcc
 ARCH = -m32
 CFLAGS += -Wall -Werror -Wfatal-errors -Wno-error=unused-variable -fstack-protector -std=c2x -g
 CFLAGS += -DDEBUG
-CFLAGS += -DDEBUG_PRINT
+#CFLAGS += -DDEBUG_PRINT
 LDFLAGS = -lm
 OPT ?= -O0
 DEPFLAGS = -MMD -MP

c/class_resolver.c

@@ -11,6 +11,7 @@
 #include "printf.h"
 #include "field_size.h"
 #include "debug.h"
+#include "fatal.h"
 
 static int field_info_field_size(struct class_file * class_file, struct field_info * field_info)
 {
@@ -270,7 +271,10 @@ struct class_entry * class_resolver_lookup_class(int class_hash_table_length,
                                                 class_hash_table,
                                                 class_name,
                                                 class_name_length);
-  assert(e != nullptr);
+  if (e == nullptr) {
+    fatal_print__class_lookup_failed__from_string(class_name, class_name_length);
+    assert(e != nullptr);
+  }
 
   return (struct class_entry *)e->value;
 }
@@ -298,9 +302,10 @@ struct class_entry * class_resolver_lookup_class_from_class_index(int class_hash
                                                                   class_hash_table,
                                                                   class_name_constant->utf8.bytes,
                                                                   class_name_constant->utf8.length);
-
-  // cache the result
-  class_entry->attribute_entry[class_index - 1].class_entry = _class_entry;
+  if (_class_entry != nullptr) {
+    // cache the result
+    class_entry->attribute_entry[class_index - 1].class_entry = _class_entry;
+  }
 
   return _class_entry;
 }

c/execute.c

@@ -1094,20 +1094,42 @@ void op_ineg(struct vm * vm)
 
 void op_instanceof(struct vm * vm, uint32_t index)
 {
-  struct class_entry * class_entry =
+  struct class_entry * index_class_entry =
     class_resolver_lookup_class_from_class_index(vm->class_hash_table.length,
                                                  vm->class_hash_table.entry,
                                                  vm->current_frame->class_entry,
                                                  index);
-  assert(class_entry != nullptr);
+  assert(index_class_entry != nullptr);
 
   int32_t * objectref = (int32_t *)operand_stack_pop_u32(vm->current_frame);
-  if (objectref == nullptr) {
-    operand_stack_push_u32(vm->current_frame, 0);
-  } else {
-    int32_t value = objectref[0] == (int32_t)class_entry;
-    operand_stack_push_u32(vm->current_frame, value);
+  bool value = false;
+  if (objectref != nullptr) {
+    struct class_entry * class_entry = (struct class_entry *)objectref[0];
+    while (true) {
+      assert(class_entry != nullptr);
+      if (class_entry == index_class_entry) {
+        value = true;
+        break;
+      }
+      if (class_entry->class_file->super_class == 0) {
+        break;
+      }
+
+      struct constant * class_constant = &class_entry->class_file->constant_pool[class_entry->class_file->super_class - 1];
+      assert(class_constant->tag == CONSTANT_Class);
+      struct constant * class_name_constant =  &class_entry->class_file->constant_pool[class_constant->class.name_index - 1];
+      assert(class_name_constant->tag == CONSTANT_Utf8);
+      print_utf8_string(class_name_constant);
+      debugf("\n");
+
+      // superclass lookup
+      class_entry = class_resolver_lookup_class_from_class_index(vm->class_hash_table.length,
+                                                                 vm->class_hash_table.entry,
+                                                                 class_entry,
+                                                                 class_entry->class_file->super_class);
+    }
   }
+  operand_stack_push_u32(vm->current_frame, (uint32_t)value);
 }
 
 void op_invokedynamic(struct vm * vm, uint32_t index)
@@ -1688,19 +1710,10 @@ void op_multianewarray(struct vm * vm, uint32_t index, uint32_t dimensions)
 
 void op_new(struct vm * vm, uint32_t index)
 {
-  struct constant * class_constant = &vm->current_frame->class_entry->class_file->constant_pool[index - 1];
-  #ifdef DEBUG
-  assert(class_constant->tag == CONSTANT_Class);
-  #endif
-  struct constant * class_name_constant = &vm->current_frame->class_entry->class_file->constant_pool[class_constant->class.name_index - 1];
-  #ifdef DEBUG
-  assert(class_name_constant->tag == CONSTANT_Utf8);
-  #endif
-
-  struct class_entry * class_entry = class_resolver_lookup_class(vm->class_hash_table.length,
-                                                                 vm->class_hash_table.entry,
-                                                                 class_name_constant->utf8.bytes,
-                                                                 class_name_constant->utf8.length);
+  struct class_entry * class_entry = class_resolver_lookup_class_from_class_index(vm->class_hash_table.length,
+                                                                                  vm->class_hash_table.entry,
+                                                                                  vm->current_frame->class_entry,
+                                                                                  index);
   assert(class_entry != nullptr);
 
   /* On successful resolution of the class, it is initialized if it has not

c/fatal.c

@@ -0,0 +1,11 @@
+#include "printf.h"
+#include "fatal.h"
+
+void fatal_print__class_lookup_failed__from_string(const uint8_t * name, int length)
+{
+  printf("class lookup failed: ");
+  for (int i = 0; i < length; i++) {
+    printc(name[i]);
+  }
+  printc('\n');
+}

c/fatal.h

@@ -0,0 +1,5 @@
+#pragma once
+
+#include <stdint.h>
+
+void fatal_print__class_lookup_failed__from_string(const uint8_t * name, int length);

c/frame.c

@@ -10,6 +10,7 @@
 #include "printf.h"
 #include "string.h"
 #include "native.h"
+#include "fatal.h"
 
 struct Code_attribute * get_code_attribute(int code_name_index,
                                            int attributes_count,
@@ -525,15 +526,13 @@ void vm_execute(struct vm * vm)
 
 void vm_start(int class_hash_table_length,
               struct hash_table_entry * class_hash_table,
-              const uint8_t * main_class,
-              int main_class_length)
+              const uint8_t * main_class_name,
+              int main_class_name_length)
 {
   struct class_entry * class_entry = class_resolver_lookup_class(class_hash_table_length,
                                                                  class_hash_table,
-                                                                 main_class,
-                                                                 main_class_length);
-
-  assert(class_entry != nullptr);
+                                                                 main_class_name,
+                                                                 main_class_name_length);
 
   const char * method_name = "main";
   int method_name_length = string_length(method_name);

c/frame.h

@@ -162,6 +162,6 @@ void vm_method_return(struct vm * vm);
 void vm_execute(struct vm * vm);
 void vm_start(int class_hash_table_length,
               struct hash_table_entry * class_hash_table,
-              const uint8_t * main_class,
-              int main_class_length);
+              const uint8_t * main_class_name,
+              int main_class_name_length);
 int descriptor_nargs(struct constant * descriptor_constant, uint8_t * return_type);

java.mk

@@ -18,7 +18,8 @@ OBJ = \
 	c/parse.o \
 	c/unparse.o \
 	c/native.o \
-	c/debug.o
+	c/debug.o \
+	c/fatal.o
 
 MAIN_DREAMCAST_OBJ = \
 	c/sh7091_scif.o \

p/TestInstanceof.java

@@ -0,0 +1,11 @@
+package p;
+
+class TestInstanceof {
+    public static boolean test() {
+        TestInstanceof t = new TestInstanceof();
+        return t instanceof Object;
+    }
+    public static void main() {
+        System.out.println(test());
+    }
+}