[PATCH 18/50] dse.c:check_mem_read_use

[Richard Sandiford <rdsandiford at googlemail dot com>]

gcc/
	* dse.c: Include rtl-iter.h.
	(check_mem_read_rtx): Change void * parameter to real type.
	Remove return value.
	(check_mem_read_use): Fix comment.  Use FOR_EACH_SUBRTX_PTR instead of
	for_each_rtx.  Don't handle null rtxes.

Index: gcc/dse.c
===================================================================
--- gcc/dse.c	2014-08-03 11:25:10.142956456 +0100
+++ gcc/dse.c	2014-08-03 11:25:25.192105241 +0100
@@ -54,6 +54,7 @@ Software Foundation; either version 3, o
 #include "is-a.h"
 #include "gimple.h"
 #include "gimple-ssa.h"
+#include "rtl-iter.h"
 
 /* This file contains three techniques for performing Dead Store
    Elimination (dse).
@@ -2089,15 +2090,13 @@ replace_read (store_info_t store_info, i
     }
 }
 
-/* A for_each_rtx callback in which DATA is the bb_info.  Check to see
-   if LOC is a mem and if it is look at the address and kill any
-   appropriate stores that may be active.  */
+/* Check the address of MEM *LOC and kill any appropriate stores that may
+   be active.  */
 
-static int
-check_mem_read_rtx (rtx *loc, void *data)
+static void
+check_mem_read_rtx (rtx *loc, bb_info_t bb_info)
 {
   rtx mem = *loc, mem_addr;
-  bb_info_t bb_info;
   insn_info_t insn_info;
   HOST_WIDE_INT offset = 0;
   HOST_WIDE_INT width = 0;
@@ -2106,10 +2105,6 @@ check_mem_read_rtx (rtx *loc, void *data
   int group_id;
   read_info_t read_info;
 
-  if (!mem || !MEM_P (mem))
-    return 0;
-
-  bb_info = (bb_info_t) data;
   insn_info = bb_info->last_insn;
 
   if ((MEM_ALIAS_SET (mem) == ALIAS_SET_MEMORY_BARRIER)
@@ -2119,20 +2114,20 @@ check_mem_read_rtx (rtx *loc, void *data
 	fprintf (dump_file, " adding wild read, volatile or barrier.\n");
       add_wild_read (bb_info);
       insn_info->cannot_delete = true;
-      return 0;
+      return;
     }
 
   /* If it is reading readonly mem, then there can be no conflict with
      another write. */
   if (MEM_READONLY_P (mem))
-    return 0;
+    return;
 
   if (!canon_address (mem, &spill_alias_set, &group_id, &offset, &base))
     {
       if (dump_file && (dump_flags & TDF_DETAILS))
 	fprintf (dump_file, " adding wild read, canon_address failure.\n");
       add_wild_read (bb_info);
-      return 0;
+      return;
     }
 
   if (GET_MODE (mem) == BLKmode)
@@ -2260,7 +2255,7 @@ check_mem_read_rtx (rtx *loc, void *data
 						 width)
 		      && replace_read (store_info, i_ptr, read_info,
 				       insn_info, loc, bb_info->regs_live))
-		    return 0;
+		    return;
 
 		  /* The bases are the same, just see if the offsets
 		     overlap.  */
@@ -2327,7 +2322,7 @@ check_mem_read_rtx (rtx *loc, void *data
 					 offset - store_info->begin, width)
 	      && replace_read (store_info, i_ptr,  read_info, insn_info, loc,
 			       bb_info->regs_live))
-	    return 0;
+	    return;
 
 	  if (!store_info->alias_set)
 	    remove = canon_true_dependence (store_info->mem,
@@ -2351,17 +2346,22 @@ check_mem_read_rtx (rtx *loc, void *data
 	  i_ptr = i_ptr->next_local_store;
 	}
     }
-  return 0;
 }
 
-/* A for_each_rtx callback in which DATA points the INSN_INFO for
+/* A note_uses callback in which DATA points the INSN_INFO for
    as check_mem_read_rtx.  Nullify the pointer if i_m_r_m_r returns
    true for any part of *LOC.  */
 
 static void
 check_mem_read_use (rtx *loc, void *data)
 {
-  for_each_rtx (loc, check_mem_read_rtx, data);
+  subrtx_ptr_iterator::array_type array;
+  FOR_EACH_SUBRTX_PTR (iter, array, loc, NONCONST)
+    {
+      rtx *loc = *iter;
+      if (MEM_P (*loc))
+	check_mem_read_rtx (loc, (bb_info_t) data);
+    }
 }