sched.c (new_insn_dead_notes): Check if the register was used in the original instruc...

[gcc.git] / gcc / haifa-sched.c

diff --git a/gcc/haifa-sched.c b/gcc/haifa-sched.c
index 8d220f04ee32055e95798869217b28b5e1c3b3e2..7fccfd2be7935495c0e0b8ca9f44e75a7419aafa 100644 (file)
--- a/gcc/haifa-sched.c
+++ b/gcc/haifa-sched.c
@@ -7621,6 +7621,13 @@ new_insn_dead_notes (pat, insn, last, orig_insn)
 
   if (GET_CODE (dest) == REG)
     {
+      /* If the original insn already used this register, we may not add new
+         notes for it.  One example for a split that needs this test is
+        when a multi-word memory access with register-indirect addressing
+        is split into multiple memory accesses with auto-increment and
+        one adjusting add instruction for the address register.  */
+      if (reg_referenced_p (dest, PATTERN (orig_insn)))
+       return;
       for (tem = last; tem != insn; tem = PREV_INSN (tem))
        {
          if (GET_RTX_CLASS (GET_CODE (tem)) == 'i'