Allow combiner to create autoinc in jump insns.

	* combine.c (can_combine_p): Allow autoinc in jumps.

From-SVN: r278656

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 5f94745c0da4cb6a7688870836feb04d06eac161..823ceca45d851a7bb8c2601c2ef3a854eb354015 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -5,6 +5,8 @@
 
        * combine.c (combine_instructions): Record costs for jumps.
 
+       * combine.c (can_combine_p): Allow autoinc in jumps.
+
 2019-11-23  Jan Hubicka  <hubicka@ucw.cz>
 
        * cif-code.def (MAX_INLINE_INSNS_SINGLE_O2_LIMIT): Remove.

diff --git a/gcc/combine.c b/gcc/combine.c
index f480633061d6baaece0993ddec23afeda3d3dcbd..2e21459f50461f5d30268d90f66b9b15ed26c42b 100644 (file)
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -2110,22 +2110,19 @@ can_combine_p (rtx_insn *insn, rtx_insn *i3, rtx_insn *pred ATTRIBUTE_UNUSED,
   is_volatile_p = volatile_refs_p (PATTERN (insn))
     ? volatile_refs_p
     : volatile_insn_p;
-    
+
   for (p = NEXT_INSN (insn); p != i3; p = NEXT_INSN (p))
     if (INSN_P (p) && p != succ && p != succ2 && is_volatile_p (PATTERN (p)))
       return 0;
 
   /* If INSN contains an autoincrement or autodecrement, make sure that
      register is not used between there and I3, and not already used in
-     I3 either.  Neither must it be used in PRED or SUCC, if they exist.
-     Also insist that I3 not be a jump; if it were one
-     and the incremented register were spilled, we would lose.  */
+     I3 either.  Neither must it be used in PRED or SUCC, if they exist.  */
 
   if (AUTO_INC_DEC)
     for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
       if (REG_NOTE_KIND (link) == REG_INC
-         && (JUMP_P (i3)
-             || reg_used_between_p (XEXP (link, 0), insn, i3)
+         && (reg_used_between_p (XEXP (link, 0), insn, i3)
              || (pred != NULL_RTX
                  && reg_overlap_mentioned_p (XEXP (link, 0), PATTERN (pred)))
              || (pred2 != NULL_RTX