/**********************************************************************

  vm.h -

  $Author: nagachika $
  created at: 04/01/01 16:56:59 JST

  Copyright (C) 2004-2007 Koichi Sasada

**********************************************************************/

#ifndef RUBY_VM_EXEC_H
#define RUBY_VM_EXEC_H

typedef long OFFSET;
typedef unsigned long lindex_t;
typedef VALUE GENTRY;
typedef rb_iseq_t *ISEQ;

#ifdef __GCC__
/* TODO: machine dependent prefetch instruction */
#define PREFETCH(pc)
#else
#define PREFETCH(pc)
#endif

#if VMDEBUG > 0
#define debugs printf
#define DEBUG_ENTER_INSN(insn) \
    rb_vmdebug_debug_print_pre(ec, GET_CFP(), GET_PC());

#if OPT_STACK_CACHING
#define SC_REGS() , reg_a, reg_b
#else
#define SC_REGS()
#endif

#define DEBUG_END_INSN() \
  rb_vmdebug_debug_print_post(ec, GET_CFP() SC_REGS());

#else

#define debugs
#define DEBUG_ENTER_INSN(insn)
#define DEBUG_END_INSN()
#endif

#define throwdebug if(0)printf
/* #define throwdebug printf */

/************************************************/
#if defined(DISPATCH_XXX)
error !
/************************************************/
#elif OPT_CALL_THREADED_CODE

#define LABEL(x)  insn_func_##x
#define ELABEL(x)
#define LABEL_PTR(x) &LABEL(x)

#define INSN_ENTRY(insn) \
  static rb_control_frame_t * \
    FUNC_FASTCALL(LABEL(insn))(rb_execution_context_t *ec, rb_control_frame_t *reg_cfp) {

#define END_INSN(insn) return reg_cfp;}

#define NEXT_INSN() return reg_cfp;

#define START_OF_ORIGINAL_INSN(x) /* ignore */
#define DISPATCH_ORIGINAL_INSN(x) return LABEL(x)(ec, reg_cfp);

/************************************************/
#elif OPT_TOKEN_THREADED_CODE || OPT_DIRECT_THREADED_CODE
/* threaded code with gcc */

#define LABEL(x)  INSN_LABEL_##x
#define ELABEL(x) INSN_ELABEL_##x
#define LABEL_PTR(x) &&LABEL(x)

#define INSN_ENTRY_SIG(insn) \
  if (0) fprintf(stderr, "exec: %s@(%d, %d)@%s:%d\n", #insn, \
		 (int)(reg_pc - reg_cfp->iseq->body->iseq_encoded), \
		 (int)(reg_cfp->pc - reg_cfp->iseq->body->iseq_encoded), \
		 RSTRING_PTR(rb_iseq_path(reg_cfp->iseq)), \
		 (int)(rb_iseq_line_no(reg_cfp->iseq, reg_pc - reg_cfp->iseq->body->iseq_encoded)));

#define INSN_DISPATCH_SIG(insn)

#define INSN_ENTRY(insn) \
  LABEL(insn): \
  INSN_ENTRY_SIG(insn); \

/* dispatcher */
#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)) && __GNUC__ == 3
#define DISPATCH_ARCH_DEPEND_WAY(addr) \
  __asm__ __volatile__("jmp *%0;\t# -- inserted by vm.h\t[length = 2]" : : "r" (addr))

#else
#define DISPATCH_ARCH_DEPEND_WAY(addr) \
				/* do nothing */
#endif

/**********************************/
#if OPT_DIRECT_THREADED_CODE

/* for GCC 3.4.x */
#define TC_DISPATCH(insn) \
  INSN_DISPATCH_SIG(insn); \
  goto *(void const *)GET_CURRENT_INSN(); \
  ;

#else
/* token threaded code */

#define TC_DISPATCH(insn)  \
  DISPATCH_ARCH_DEPEND_WAY(insns_address_table[GET_CURRENT_INSN()]); \
  INSN_DISPATCH_SIG(insn); \
  goto *insns_address_table[GET_CURRENT_INSN()]; \
  rb_bug("tc error");


#endif /* DISPATCH_DIRECT_THREADED_CODE */

#define END_INSN(insn)      \
  DEBUG_END_INSN();         \
  TC_DISPATCH(insn);

#define INSN_DISPATCH()     \
  TC_DISPATCH(__START__)    \
  {

#define END_INSNS_DISPATCH()    \
      rb_bug("unknown insn: %"PRIdVALUE, GET_CURRENT_INSN());   \
  }   /* end of while loop */   \

#define NEXT_INSN() TC_DISPATCH(__NEXT_INSN__)

#define START_OF_ORIGINAL_INSN(x) start_of_##x:
#define DISPATCH_ORIGINAL_INSN(x) goto  start_of_##x;

/************************************************/
#else /* no threaded code */
/* most common method */

#define INSN_ENTRY(insn) \
case BIN(insn):

#define END_INSN(insn)                        \
  DEBUG_END_INSN();                           \
  break;

#define INSN_DISPATCH()         \
  while (1) {			\
    switch (GET_CURRENT_INSN()) {

#define END_INSNS_DISPATCH()    \
default:                        \
  SDR(); \
      rb_bug("unknown insn: %ld", GET_CURRENT_INSN());   \
    } /* end of switch */       \
  }   /* end of while loop */   \

#define NEXT_INSN() goto first

#define START_OF_ORIGINAL_INSN(x) start_of_##x:
#define DISPATCH_ORIGINAL_INSN(x) goto  start_of_##x;

#endif

#define VM_SP_CNT(ec, sp) ((sp) - (ec)->vm_stack)

#if OPT_CALL_THREADED_CODE
#define THROW_EXCEPTION(exc) do { \
    ec->errinfo = (VALUE)(exc); \
    return 0; \
} while (0)
#else
#define THROW_EXCEPTION(exc) return (VALUE)(exc)
#endif

#define SCREG(r) (reg_##r)

#define VM_DEBUG_STACKOVERFLOW 0

#if VM_DEBUG_STACKOVERFLOW
#define CHECK_VM_STACK_OVERFLOW_FOR_INSN(cfp, margin) \
    WHEN_VM_STACK_OVERFLOWED(cfp, (cfp)->sp, margin) vm_stack_overflow_for_insn()
#else
#define CHECK_VM_STACK_OVERFLOW_FOR_INSN(cfp, margin)
#endif

#endif /* RUBY_VM_EXEC_H */
