pike.git/ src/ interpret.h

2016-07-27

2016-07-27 18:12:46 by Arne Goedeke <el@laramies.com>

• bca80a1206c5a08116e7b8334be3e431e9a4764c (83 lines) (+60/-23) ^{[ Show | Annotate ]}
  Branch: 8.1

Interpreter: simplify struct pike_frame

- expendibles and save_sp are usually only used during setup and frame
deallocation. It is enough to store them as offsets from 'locals'
- reordered the struct entries to avoid some padding

62:   struct pike_frame   {    INT32 refs;/* must be first */ -  INT32 args; /** Actual number of arguments. */ -  INT16 num_locals; /** Number of local variables. */ -  INT16 num_args; /** Number of argument variables. */ +  +  /* The folloing fields are only used during setup and teardown */    unsigned INT16 fun; /** Function number. */ -  unsigned INT16 flags; /** PIKE_FRAME_* */ -  INT16 ident; -  struct pike_frame *next; -  struct pike_frame *scope; +  INT16 ident; /** Function identifier offset */ +  +  struct pike_frame *next; /** parent frame */ +  struct pike_frame *scope; /** scope */ +  struct svalue **save_mark_sp; /** saved mark sp level */ +     PIKE_OPCODE_T *pc; /** Address of current opcode. */ -  PIKE_OPCODE_T *return_addr; /** Address of opcode to continue at after call. */ +     struct svalue *locals; /** Start of local variables. */ -  +  char *current_storage; /** == current_object->storage + context->storage_offset */ +  struct object *current_object; +  struct inherit *context; /** inherit context */ +  struct program *current_program; /* program containing the context. */ +  PIKE_OPCODE_T *return_addr; /** Address of opcode to continue at after call. */    -  /** This is <= locals, and this is where the -  * return value should go. +  unsigned INT16 flags; /** PIKE_FRAME_* */ +  /** +  * This tells us the current level of svalues on the stack that can +  * be discarded once the current function is done with them. It is an offset +  * from locals and is always positive.    */ -  struct svalue *save_sp; +  INT16 expendible_offset; +  INT16 num_locals; /** Number of local variables. */ +  INT16 num_args; /** Number of argument variables. */    -  +  INT32 args; /** Actual number of arguments passed to the function. */    /** -  * This tells us the current level of svalues on the stack that can -  * be discarded once the current function is done with them +  * This is an offset from locals and denotes the place where the return value +  * should go. +  * +  * It can be -1 if the function to be called is on the stack. +  * It can be even more negative in case of recursion when the return value location +  * get replaced by that of the previous frame.    */ -  struct svalue *expendible; -  struct svalue **save_mark_sp; -  struct object *current_object; -  struct program *current_program; /* program containing the context. */ -  struct inherit *context; -  char *current_storage; +  INT16 save_sp_offset;      #ifdef PROFILING    cpu_time_t children_base; /** Accounted time when the frame started. */
96:   #endif /* PROFILING */   };    + static inline struct svalue *frame_get_save_sp(const struct pike_frame *frame) { +  return frame->locals + frame->save_sp_offset; + } +  + static inline void frame_set_save_sp(struct pike_frame *frame, struct svalue *sv) { +  ptrdiff_t n = sv - frame->locals; + #ifdef PIKE_DEBUG +  if (n < MIN_INT16 || n > MAX_INT16) +  Pike_error("Save SP offset too large.\n"); + #endif +  frame->save_sp_offset = n; + } +  + static inline struct svalue *frame_get_expendible(const struct pike_frame *frame) { +  return frame->locals + frame->expendible_offset; + } +  + static inline void frame_set_expendible(struct pike_frame *frame, struct svalue *sv) { +  ptrdiff_t n = sv - frame->locals; + #ifdef PIKE_DEBUG +  if (n < MIN_INT16 || n > MAX_INT16) +  Pike_error("Expendible offset too large.\n"); + #endif +  frame->expendible_offset = n; + } +    #define PIKE_FRAME_RETURN_INTERNAL 1   #define PIKE_FRAME_RETURN_POP 2   #define PIKE_FRAME_MALLOCED_LOCALS 0x8000
514:    { \    really_free_pike_frame(_fp_); \    }else{ \ -  ptrdiff_t num_expendible = _fp_->expendible - _fp_->locals; \ +  ptrdiff_t num_expendible = _fp_->expendible_offset; \    DO_IF_DEBUG( \    if( (_fp_->locals + _fp_->num_locals > Pike_sp) || \ -  (Pike_sp < _fp_->expendible) || \ +  (Pike_sp < _fp_->locals + _fp_->expendible_offset) || \    (num_expendible < 0) || (num_expendible > _fp_->num_locals)) \ -  Pike_fatal("Stack failure in POP_PIKE_FRAME %p+%d=%p %p %p!\n", \ +  Pike_fatal("Stack failure in POP_PIKE_FRAME %p+%d=%p %p %hd!\n", \    _fp_->locals, _fp_->num_locals, \    _fp_->locals+_fp_->num_locals, \ -  Pike_sp,_fp_->expendible)); \ +  Pike_sp,_fp_->expendible_offset)); \    debug_malloc_touch(_fp_); \    if(num_expendible) \    { \