contrib/gcc/mode-switching.c

1 /* CPU mode switching
40 /* We want target macros for the mode switching code to be able to refer
47    and finding all the insns which require a specific mode.  Each insn gets
54    mode are given a single entry, without a mode.  (Each basic block
61    priority mode, till for each entity all modes are exhausted.
67    either single or double mode to be set.
68    MODE is the mode this insn must be executed in.
75   int mode;
106 new_seginfo (int mode, rtx insn, int bb, HARD_REG_SET regs_live)
110   ptr->mode = mode;
140    denotes that a mode set is to be done on that edge.
142    we are currently handling mode-switching for.  */
231 	   insert the final mode switch before the return value copy
290 		       different mode than the exit block.  */
294 			int mode = MODE_NEEDED (e, return_copy);
296 			if (mode != num_modes[e] && mode != MODE_EXIT (e))
302 			   thus we might need to put the final mode switch
361 		   require a different mode than MODE_EXIT, so if we might
384 /* Find all insns that need a particular mode setting, and insert the
385    necessary mode switches.  Return true if we did work.  */
450       /* Determine what the first use (if any) need for a mode of entity E is.
451 	 This will be the mode that is anticipatable for this block.
462 	  /* Pretend the mode is clobbered across abnormal edges.  */
483 		  int mode = MODE_NEEDED (e, insn);
486 		  if (mode != no_mode && mode != last_mode)
488 		      last_mode = mode;
489 		      ptr = new_seginfo (mode, insn, bb->index, live_now);
509 	  /* Check for blocks without ANY mode requirements.  */
518 	int mode = MODE_ENTRY (e);
520 	if (mode != no_mode)
531 	       blocks which compute no mode. This represents the mode on
533 	    info[bb->index].computing = mode;
536 	      info[pre_exit->index].seginfo->mode = MODE_EXIT (e);
559 	      if (info[bb->index].seginfo->mode == m)
568 	 placement mode switches to modes with priority I.  */
577 	  /* Insert all mode sets that have been inserted by lcm.  */
580 	  /* Wherever we have moved a mode setting upwards in the flow graph,
583 	     mode of the same entity.  First set the aux field of each
590 	      int mode;
602 	      mode = current_mode[j];
609 	      EMIT_MODE_SET (entity_map[j], mode, live_at_edge);
628 		/* Cancel the 'deleted' mode set.  */
629 		bb_info[j][bb->index].seginfo->mode = no_mode;
639   /* Now output the remaining mode sets in all the segments.  */
650 	      if (ptr->mode != no_mode)
655 		  EMIT_MODE_SET (entity_map[j], ptr->mode, ptr->regs_live);
732   "mode-sw",                            /* name */