--- a/gcc/sched-deps.c	Thu Oct 25 08:08:40 2018 +0900
+++ b/gcc/sched-deps.c	Thu Oct 25 10:21:07 2018 +0900
@@ -1,6 +1,6 @@
 /* Instruction scheduling pass.  This file computes dependencies between
    instructions.
-   Copyright (C) 1992-2017 Free Software Foundation, Inc.
+   Copyright (C) 1992-2018 Free Software Foundation, Inc.
    Contributed by Michael Tiemann (tiemann@cygnus.com) Enhanced by,
    and currently maintained by, Jim Wilson (wilson@cygnus.com)
 
@@ -2319,6 +2319,13 @@
 	  while (--i >= 0)
 	    note_reg_use (regno + i);
 	}
+      else if (ref == CLOBBER_HIGH)
+	{
+	  gcc_assert (i == 1);
+	  /* We don't know the current state of the register, so have to treat
+	     the clobber high as a full clobber.  */
+	  note_reg_clobber (regno);
+	}
       else
 	{
 	  while (--i >= 0)
@@ -2342,6 +2349,8 @@
       else if (ref == USE)
 	note_reg_use (regno);
       else
+	/* For CLOBBER_HIGH, we don't know the current state of the register,
+	   so have to treat it as a full clobber.  */
 	note_reg_clobber (regno);
 
       /* Pseudos that are REG_EQUIV to something may be replaced
@@ -2834,10 +2843,16 @@
 sched_macro_fuse_insns (rtx_insn *insn)
 {
   rtx_insn *prev;
+  /* No target hook would return true for debug insn as any of the
+     hook operand, and with very large sequences of only debug insns
+     where on each we call sched_macro_fuse_insns it has quadratic
+     compile time complexity.  */
+  if (DEBUG_INSN_P (insn))
+    return;
   prev = prev_nonnote_nondebug_insn (insn);
   if (!prev)
     return;
- 
+
   if (any_condjump_p (insn))
     {
       unsigned int condreg1, condreg2;
@@ -2891,7 +2906,8 @@
 			 && code == SET);
 
   /* Group compare and branch insns for macro-fusion.  */
-  if (targetm.sched.macro_fusion_p
+  if (!deps->readonly
+      && targetm.sched.macro_fusion_p
       && targetm.sched.macro_fusion_p ())
     sched_macro_fuse_insns (insn);
 
@@ -2916,6 +2932,8 @@
 	= alloc_INSN_LIST (insn, deps->sched_before_next_jump);
 
       /* Make sure epilogue insn is scheduled after preceding jumps.  */
+      add_dependence_list (insn, deps->last_pending_memory_flush, 1,
+			   REG_DEP_ANTI, true);
       add_dependence_list (insn, deps->pending_jump_insns, 1, REG_DEP_ANTI,
 			   true);
     }
@@ -2953,7 +2971,7 @@
 	      sub = COND_EXEC_CODE (sub);
 	      code = GET_CODE (sub);
 	    }
-	  if (code == SET || code == CLOBBER)
+	  else if (code == SET || code == CLOBBER || code == CLOBBER_HIGH)
 	    sched_analyze_1 (deps, sub, insn);
 	  else
 	    sched_analyze_2 (deps, sub, insn);
@@ -2969,6 +2987,10 @@
 	{
 	  if (GET_CODE (XEXP (link, 0)) == CLOBBER)
 	    sched_analyze_1 (deps, XEXP (link, 0), insn);
+	  else if (GET_CODE (XEXP (link, 0)) == CLOBBER_HIGH)
+	    /* We could support CLOBBER_HIGH and treat it in the same way as
+	      HARD_REGNO_CALL_PART_CLOBBERED, but no port needs that yet.  */
+	    gcc_unreachable ();
 	  else if (GET_CODE (XEXP (link, 0)) != SET)
 	    sched_analyze_2 (deps, XEXP (link, 0), insn);
 	}