[gcc(refs/vendors/riscv/heads/gcc-13-with-riscv-opts)] mode-switching: Use 1-based edge aux fields

[gcc(refs/vendors/riscv/heads/gcc-13-with-riscv-opts)] mode-switching: Use 1-based edge aux fields

[Jeff Law]

https://gcc.gnu.org/g:b8fc4df2ffae7489957d87b9dd1efd09302c1db0

commit b8fc4df2ffae7489957d87b9dd1efd09302c1db0
Author: Richard Sandiford <richard.sandiford@arm.com>
Date:   Sat Nov 11 17:28:59 2023 +0000

    mode-switching: Use 1-based edge aux fields
    
    The pass used the edge aux field to record which mode change
    should happen on the edge, with -1 meaning "none".  It's more
    convenient for later patches to leave aux zero for "none",
    and use numbers based at 1 to record a change.
    
    gcc/
            * mode-switching.cc (commit_mode_sets): Use 1-based edge aux values.
    
    (cherry picked from commit 718228a6f479fe252e0e6f71933c2465b7b480a9)

Diff:
---
 gcc/mode-switching.cc | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/gcc/mode-switching.cc b/gcc/mode-switching.cc
index 7a5c4993d65..6b5661131e3 100644
--- a/gcc/mode-switching.cc
+++ b/gcc/mode-switching.cc
@@ -106,10 +106,10 @@ commit_mode_sets (struct edge_list *edge_list, int e, struct bb_info *info)
   for (int ed = NUM_EDGES (edge_list) - 1; ed >= 0; ed--)
     {
       edge eg = INDEX_EDGE (edge_list, ed);
-      int mode;
 
-      if ((mode = (int)(intptr_t)(eg->aux)) != -1)
+      if (eg->aux)
 	{
+	  int mode = (int) (intptr_t) eg->aux - 1;
 	  HARD_REG_SET live_at_edge;
 	  basic_block src_bb = eg->src;
 	  int cur_mode = info[src_bb->index].mode_out;
@@ -728,14 +728,14 @@ optimize_mode_switching (void)
 	{
 	  edge eg = INDEX_EDGE (edge_list, ed);
 
-	  eg->aux = (void *)(intptr_t)-1;
+	  eg->aux = (void *) (intptr_t) 0;
 
 	  for (i = 0; i < no_mode; i++)
 	    {
 	      int m = targetm.mode_switching.priority (entity_map[j], i);
 	      if (mode_bit_p (insert[ed], j, m))
 		{
-		  eg->aux = (void *)(intptr_t)m;
+		  eg->aux = (void *) (intptr_t) (m + 1);
 		  break;
 		}
 	    }