[see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55030 comments 11 and 13 <mikpe@it.uu.se>]

gcc/

2013-05-26  Mikael Pettersson  <mikpe@it.uu.se>

	PR middle-end/55030
	Revert:

	2012-11-26  Hans-Peter Nilsson  <hp@bitrange.com>

	PR middle-end/55030
	* dse.c (scan_insn): Where checking for blocking insns, use
	volatile_insn_p instead of manual check for volatile ASM.
	* cselib.c (cselib_process_insn): Ditto.

--- gcc-4.8.0/gcc/cselib.c.~1~	2013-01-10 21:38:27.000000000 +0100
+++ gcc-4.8.0/gcc/cselib.c	2013-05-26 14:32:14.071461498 +0200
@@ -2623,12 +2623,13 @@ cselib_process_insn (rtx insn)
 
   cselib_current_insn = insn;
 
-  /* Forget everything at a CODE_LABEL, a volatile insn, or a setjmp.  */
+  /* Forget everything at a CODE_LABEL, a volatile asm, or a setjmp.  */
   if ((LABEL_P (insn)
        || (CALL_P (insn)
 	   && find_reg_note (insn, REG_SETJMP, NULL))
        || (NONJUMP_INSN_P (insn)
-	   && volatile_insn_p (PATTERN (insn))))
+	   && GET_CODE (PATTERN (insn)) == ASM_OPERANDS
+	   && MEM_VOLATILE_P (PATTERN (insn))))
       && !cselib_preserve_constants)
     {
       cselib_reset_table (next_uid);
--- gcc-4.8.0/gcc/dse.c.~1~	2013-03-09 23:04:15.000000000 +0100
+++ gcc-4.8.0/gcc/dse.c	2013-05-26 14:32:14.071461498 +0200
@@ -2518,7 +2518,8 @@ scan_insn (bb_info_t bb_info, rtx insn)
   /* Cselib clears the table for this case, so we have to essentially
      do the same.  */
   if (NONJUMP_INSN_P (insn)
-      && volatile_insn_p (PATTERN (insn)))
+      && GET_CODE (PATTERN (insn)) == ASM_OPERANDS
+      && MEM_VOLATILE_P (PATTERN (insn)))
     {
       add_wild_read (bb_info);
       insn_info->cannot_delete = true;