expr.c

gcc-2.95.3 Linux下最常用的C编译器

      expand_assignment (field_ref, new_value, 0, 0);
    }
  else
    push_value (field_ref);
}

tree
build_primtype_type_ref (self_name)
    char *self_name;
{
  char *class_name = self_name+10;
  tree typ;
  if (strncmp(class_name, "Byte", 4) == 0)
    typ = byte_type_node;
  else if (strncmp(class_name, "Short", 5) == 0)
    typ = short_type_node;
  else if (strncmp(class_name, "Integer", 7) == 0)
    typ = int_type_node;
  else if (strncmp(class_name, "Long", 4) == 0)
    typ = long_type_node;
  else if (strncmp(class_name, "Float", 5) == 0)
    typ = float_type_node;
  else if (strncmp(class_name, "Double", 6) == 0)
    typ = double_type_node;
  else if (strncmp(class_name, "Boolean", 7) == 0)
    typ = boolean_type_node;
  else if (strncmp(class_name, "Char", 4) == 0)
    typ = char_type_node;
  else if (strncmp(class_name, "Void", 4) == 0)
    typ = void_type_node;
  else
    typ = NULL_TREE;
  if (typ != NULL_TREE)
    return build_class_ref (typ);
  else
    return NULL_TREE;
}

void
load_type_state (label)
     tree label;
{
  int i;
  tree vec = LABEL_TYPE_STATE (label);
  int cur_length = TREE_VEC_LENGTH (vec);
  stack_pointer = cur_length - DECL_MAX_LOCALS(current_function_decl);
  for (i = 0; i < cur_length; i++)
    type_map [i] = TREE_VEC_ELT (vec, i);
}

/* Do the expansion of a Java switch. With Gcc, switches are front-end
   dependant things, but they rely on gcc routines. This function is
   placed here because it uses things defined locally in parse.y. */

static tree
case_identity (t, v)
     tree t __attribute__ ((__unused__));
     tree v;
{
  return v;
}

struct rtx_def *
java_lang_expand_expr (exp, target, tmode, modifier)
     register tree exp;
     rtx target;
     enum machine_mode tmode;
     enum expand_modifier modifier;
{
  tree current;

  switch (TREE_CODE (exp))
    {
    case NEW_ARRAY_INIT:
      {
	rtx tmp;
	tree array_type = TREE_TYPE (TREE_TYPE (exp));
	tree element_type = TYPE_ARRAY_ELEMENT (array_type);
	tree data_fld = TREE_CHAIN (TREE_CHAIN (TYPE_FIELDS (array_type)));
	HOST_WIDE_INT ilength = java_array_type_length (array_type);
	tree length = build_int_2 (ilength, 0);
	tree init = TREE_OPERAND (exp, 0);
	tree array_decl;
#if 0
	/* Enable this once we can set the vtable field statically.  FIXME */
	if (TREE_CONSTANT (init) && TREE_STATIC (exp)
	    && JPRIMITIVE_TYPE_P (element_type))
	  {
	    tree temp, value, init_decl;
	    START_RECORD_CONSTRUCTOR (temp, object_type_node);
	    PUSH_FIELD_VALUE (temp, "vtable",
			      null_pointer_node /* FIXME */
			      );
	    PUSH_FIELD_VALUE (temp, "sync_info", null_pointer_node);
	    FINISH_RECORD_CONSTRUCTOR (temp);
	    START_RECORD_CONSTRUCTOR (value, array_type);
	    PUSH_SUPER_VALUE (value, temp);
	    PUSH_FIELD_VALUE (value, "length", length);
	    PUSH_FIELD_VALUE (value, "data", init);
	    FINISH_RECORD_CONSTRUCTOR (value);

	    init_decl = build_decl (VAR_DECL, generate_name (), array_type);
	    pushdecl_top_level (init_decl);
	    TREE_STATIC (init_decl) = 1;
	    DECL_INITIAL (init_decl) = value;
	    DECL_IGNORED_P (init_decl) = 1;
	    TREE_READONLY (init_decl) = 1;
	    make_decl_rtl (init_decl, NULL, 1);
	    init = build1 (ADDR_EXPR, TREE_TYPE (exp), init_decl);
	    return expand_expr (init, target, tmode, modifier);
	  }
#endif
	array_decl = build_decl (VAR_DECL, NULL_TREE, TREE_TYPE (exp));
	expand_decl (array_decl);
	tmp = expand_assignment (array_decl,
				 build_new_array (element_type, length),
				 1, 0);
	if (TREE_CONSTANT (init)
	    && ilength >= 10 && JPRIMITIVE_TYPE_P (element_type))
	  {
	    tree init_decl = build_decl (VAR_DECL, generate_name (),
					 TREE_TYPE (init));
	    pushdecl_top_level (init_decl);
	    TREE_STATIC (init_decl) = 1;
	    DECL_INITIAL (init_decl) = init;
	    DECL_IGNORED_P (init_decl) = 1;
	    TREE_READONLY (init_decl) = 1;
	    make_decl_rtl (init_decl, NULL, 1);
	    init = init_decl;
	  }
	expand_assignment (build (COMPONENT_REF, TREE_TYPE (data_fld),
				  build1 (INDIRECT_REF, array_type, array_decl),
				  data_fld),
			   init, 0, 0);
	return tmp;
      }
    case BLOCK:
      if (BLOCK_EXPR_BODY (exp))
	{
	  tree local;
	  tree body = BLOCK_EXPR_BODY (exp);
	  struct rtx_def *to_return;
	  pushlevel (2);	/* 2 and above */
	  expand_start_bindings (0);
	  local = BLOCK_EXPR_DECLS (exp);
	  while (local)
	    {
	      tree next = TREE_CHAIN (local);
	      layout_decl (local, 0);
	      expand_decl (pushdecl (local));
	      local = next;
	    }
	  /* Avoid deep recursion for long block.  */
	  while (TREE_CODE (body) == COMPOUND_EXPR)
	    {
	      expand_expr (TREE_OPERAND (body, 0), const0_rtx, VOIDmode, 0);
	      emit_queue ();
	      body = TREE_OPERAND (body, 1);
	    }
	  to_return = expand_expr (body, target, tmode, modifier);
	  poplevel (1, 1, 0);
	  expand_end_bindings (getdecls (), 1, 0);
	  return to_return;
	}
      break;

    case CASE_EXPR:
      {
	tree duplicate;
	if (pushcase (TREE_OPERAND (exp, 0), case_identity,
		      build_decl (LABEL_DECL, NULL_TREE, NULL_TREE), 
		      &duplicate) == 2)
	  {
	    EXPR_WFL_LINECOL (wfl_operator) = EXPR_WFL_LINECOL (exp);
	    parse_error_context
	      (wfl_operator, "Duplicate case label: `%s'",
	       print_int_node (TREE_OPERAND (exp, 0)));
	  }
	return const0_rtx;
      }

    case DEFAULT_EXPR:
      pushcase (NULL_TREE, 0, 
		build_decl (LABEL_DECL, NULL_TREE, NULL_TREE), NULL);
      return const0_rtx;

    case SWITCH_EXPR:
      expand_start_case (0, TREE_OPERAND (exp, 0), int_type_node, "switch");
      expand_expr_stmt (TREE_OPERAND (exp, 1));
      expand_end_case (TREE_OPERAND (exp, 0));
      return const0_rtx;

    case TRY_EXPR:
      /* We expand a try[-catch] block */

      /* Expand the try block */
      expand_eh_region_start ();
      expand_expr_stmt (TREE_OPERAND (exp, 0));
      expand_start_all_catch ();

      /* Expand all catch clauses (EH handlers) */
      for (current = TREE_OPERAND (exp, 1); current; 
	   current = TREE_CHAIN (current))
	{
	  tree type;
	  tree catch = TREE_OPERAND (current, 0);
	  tree decl = BLOCK_EXPR_DECLS (catch);
	  type = (decl ? TREE_TYPE (TREE_TYPE (decl)) : NULL_TREE);
	  start_catch_handler (prepare_eh_table_type (type));
	  expand_expr_stmt (TREE_OPERAND (current, 0));

	  expand_resume_after_catch ();
	  end_catch_handler ();
	}
      expand_end_all_catch ();
      break;

    default:
      fatal ("Can't expand '%s' tree - java_lang_expand_expr",
	     tree_code_name [TREE_CODE (exp)]);
    }
}

void
expand_byte_code (jcf, method)
     JCF *jcf;
     tree method;
{
  int PC;
  int i;
  int saw_index;
  unsigned char *linenumber_pointer;
  int dead_code_index = -1;

#undef RET /* Defined by config/i386/i386.h */
#undef AND /* Causes problems with opcodes for iand and land. */
#undef PTR
#define BCODE byte_ops
#define BYTE_type_node byte_type_node
#define SHORT_type_node short_type_node
#define INT_type_node int_type_node
#define LONG_type_node long_type_node
#define CHAR_type_node char_type_node
#define PTR_type_node ptr_type_node
#define FLOAT_type_node float_type_node
#define DOUBLE_type_node double_type_node
#define VOID_type_node void_type_node
  jint INT_temp;
  unsigned char* byte_ops;
  long length = DECL_CODE_LENGTH (method);

  stack_pointer = 0;
  JCF_SEEK (jcf, DECL_CODE_OFFSET (method));
  byte_ops = jcf->read_ptr;

#define CONST_INDEX_1 (saw_index = 1, IMMEDIATE_u1)
#define CONST_INDEX_2 (saw_index = 1, IMMEDIATE_u2)
#define VAR_INDEX_1 (saw_index = 1, IMMEDIATE_u1)
#define VAR_INDEX_2 (saw_index = 1, IMMEDIATE_u2)

#define CHECK_PC_IN_RANGE(PC) ((void)1) /* Already handled by verifier. */

  instruction_bits = oballoc (length + 1);
  bzero (instruction_bits, length + 1);

  /* We make an initial pass of the line number table, to note
     which instructions have associated line number entries. */
  linenumber_pointer = linenumber_table;
  for (i = 0; i < linenumber_count; i++)
    {
      int pc = GET_u2 (linenumber_pointer);
      linenumber_pointer += 4;
      if (pc >= length)
	warning ("invalid PC in line number table");
      else
	{
	  if ((instruction_bits[pc] & BCODE_HAS_LINENUMBER) != 0)
	    instruction_bits[pc] |= BCODE_HAS_MULTI_LINENUMBERS;
	  instruction_bits[pc] |= BCODE_HAS_LINENUMBER;
	}
    }  

  /* Do a preliminary pass.
   * This figures out which PC can be the targets of jumps. */
  for (PC = 0; PC < length;)
    {
      int oldpc = PC; /* PC at instruction start. */
      instruction_bits [PC] |=  BCODE_INSTRUCTION_START;
      switch (byte_ops[PC++])
	{
#define JAVAOP(OPNAME, OPCODE, OPKIND, OPERAND_TYPE, OPERAND_VALUE) \
        case OPCODE: \
	  PRE_##OPKIND(OPERAND_TYPE, OPERAND_VALUE); \
	  break;

#define NOTE_LABEL(PC) note_label(oldpc, PC)

#define PRE_PUSHC(OPERAND_TYPE, OPERAND_VALUE) (void)(OPERAND_VALUE);
#define PRE_LOAD(OPERAND_TYPE, OPERAND_VALUE) (void)(OPERAND_VALUE);
#define PRE_STORE(OPERAND_TYPE, OPERAND_VALUE) (void)(OPERAND_VALUE);
#define PRE_STACK(OPERAND_TYPE, OPERAND_VALUE) /* nothing */
#define PRE_UNOP(OPERAND_TYPE, OPERAND_VALUE) /* nothing */
#define PRE_BINOP(OPERAND_TYPE, OPERAND_VALUE) /* nothing */
#define PRE_CONVERT(OPERAND_TYPE, OPERAND_VALUE) /* nothing */
#define PRE_CONVERT2(OPERAND_TYPE, OPERAND_VALUE) /* nothing */

#define PRE_SPECIAL(OPERAND_TYPE, INSTRUCTION) \
  PRE_SPECIAL_##INSTRUCTION(OPERAND_TYPE)
#define PRE_SPECIAL_IINC(OPERAND_TYPE) \
  ((void) IMMEDIATE_u1, (void) IMMEDIATE_s1)
#define PRE_SPECIAL_ENTER(IGNORE) /* nothing */
#define PRE_SPECIAL_EXIT(IGNORE) /* nothing */
#define PRE_SPECIAL_THROW(IGNORE) /* nothing */
#define PRE_SPECIAL_BREAK(IGNORE) /* nothing */

/* two forms of wide instructions */
#define PRE_SPECIAL_WIDE(IGNORE) \
  { \
    int modified_opcode = IMMEDIATE_u1; \
    if (modified_opcode == OPCODE_iinc)	\
      { \
	(void) IMMEDIATE_u2;	/* indexbyte1 and indexbyte2 */ \
	(void) IMMEDIATE_s2;	/* constbyte1 and constbyte2 */ \
      } \
    else \
      { \
	(void) IMMEDIATE_u2;	/* indexbyte1 and indexbyte2 */ \
      } \
  }

/* nothing */ /* XXX JH */

#define PRE_IMPL(IGNORE1, IGNORE2) /* nothing */

#define PRE_MONITOR(OPERAND_TYPE, OPERAND_VALUE) /* nothing */

#define PRE_RETURN(OPERAND_TYPE, OPERAND_VALUE) /* nothing */
#define PRE_ARRAY(OPERAND_TYPE, SUBOP) \
	  PRE_ARRAY_##SUBOP(OPERAND_TYPE)
#define PRE_ARRAY_LOAD(TYPE) /* nothing */
#define PRE_ARRAY_STORE(TYPE) /* nothing */
#define PRE_ARRAY_LENGTH(TYPE) /* nothing */
#define PRE_ARRAY_NEW(TYPE) PRE_ARRAY_NEW_##TYPE
#define PRE_ARRAY_NEW_NUM ((void) IMMEDIATE_u1)
#define PRE_ARRAY_NEW_PTR ((void) IMMEDIATE_u2)
#define PRE_ARRAY_NEW_MULTI ((void) IMMEDIATE_u2, (void) IMMEDIATE_u1)

#define PRE_TEST(OPERAND_TYPE, OPERAND_VALUE) NOTE_LABEL (oldpc+IMMEDIATE_s2)
#define PRE_COND(OPERAND_TYPE, OPERAND_VALUE) NOTE_LABEL (oldpc+IMMEDIATE_s2)
#define PRE_BRANCH(OPERAND_TYPE, OPERAND_VALUE) \
  saw_index = 0;  INT_temp = (OPERAND_VALUE); \
  if (!saw_index)  NOTE_LABEL(oldpc + INT_temp);
#define PRE_JSR(OPERAND_TYPE, OPERAND_VALUE) \
  saw_index = 0;  INT_temp = (OPERAND_VALUE); \
  if (!saw_index)  NOTE_LABEL(oldpc + INT_temp);

#define PRE_RET(OPERAND_TYPE, OPERAND_VALUE)  (void)(OPERAND_VALUE)

#define PRE_SWITCH(OPERAND_TYPE, TABLE_OR_LOOKUP) \
  PC = (PC + 3) / 4 * 4; PRE_##TABLE_OR_LOOKUP##_SWITCH

#define PRE_LOOKUP_SWITCH						\
  { jint default_offset = IMMEDIATE_s4;  jint npairs = IMMEDIATE_s4;	\
    NOTE_LABEL (default_offset+oldpc);					\
    if (npairs >= 0)							\
      while (--npairs >= 0) {						\
       jint match ATTRIBUTE_UNUSED = IMMEDIATE_s4;			\
       jint offset = IMMEDIATE_s4;					\
       NOTE_LABEL (offset+oldpc); }					\
  }

#define PRE_TABLE_SWITCH				\
  { jint default_offset = IMMEDIATE_s4;			\
    jint low = IMMEDIATE_s4; jint high = IMMEDIATE_s4;	\
    NOTE_LABEL (default_offset+oldpc);			\
    if (low <= high)					\
     while (low++ <= high) {				\
       jint offset = IMMEDIATE_s4;			\
       NOTE_LABEL (offset+oldpc); }			\
  }

#define PRE_FIELD(MAYBE_STATIC, PUT_OR_GET) (void)(IMMEDIATE_u2);
#define PRE_OBJECT(MAYBE_STATIC, PUT_OR_GET) (void)(IMMEDIATE_u2);
#define PRE_INVOKE(MAYBE_STATIC, IS_INTERFACE) \
  (void)(IMMEDIATE_u2); \
  PC += 2 * IS_INTERFACE /* for invokeinterface */;

#include "javaop.def"
#undef JAVAOP
	}
    } /* for */

  if (! verify_jvm_instructions (jcf, byte_ops, length))
    return;

  /* Translate bytecodes to rtl instructions. */
  linenumber_pointer = linenumber_table;
  for (PC = 0; PC < length;)
    {
      if ((instruction_bits [PC] & BCODE_TARGET) != 0 || PC == 0)
	{
	  tree label = lookup_label (PC);
          flush_quick_stack ();
	  if ((instruction_bits [PC] & BCODE_TARGET) != 0)
	    expand_label (label);
	  if (LABEL_VERIFIED (label) || PC == 0)
	    load_type_state (label);
	}

      if (! (instruction_bits [PC] & BCODE_VERIFIED))
	{
	  if (dead_code_index == -1)
	    {
	      /* This is the start of a region of unreachable bytecodes.
                 They still need to be processed in order for EH ranges
                 to get handled correctly.  However, we can simply
                 replace these bytecodes with nops.  */
	      dead_code_index = PC;
            }
          
          /* Turn this bytecode into a nop.  */
          byte_ops[PC] = 0x0;
        }
       else
        {
	  if (dead_code_index != -1)
	    {
              /* We've just reached the end of a region of dead code.  */
              warning ("Unreachable bytecode from %d to before %d.",
                       dead_code_index, PC);
              dead_code_index = -1;
            }
	}

      /* Handle possible line number entry for this PC.

	 This code handles out-of-order and multiple linenumbers per PC,
	 but is optimized f