combine.c (can_combine_p): Don't combine with an asm whose output is a hard register.

        * combine.c (can_combine_p): Don't combine with an asm whose
        output is a hard register.

From-SVN: r15940

gcc/ChangeLog

+Thu Oct 16 15:07:51 1997  Richard Henderson  <rth@cygnus.com>
+
+	* combine.c (can_combine_p): Don't combine with an asm whose
+	output is a hard register.
+
 Thu Oct 16 15:43:26 1997  Mike Stump  (mrs@wrs.com)
 
 	* c-decl.c (start_struct): Ensure that structs with forward

gcc/combine.c

@@ -1003,6 +1003,13 @@ can_combine_p (insn, i3, pred, succ, pdest, psrc)
 	  && p != succ && volatile_refs_p (PATTERN (p)))
 	return 0;
 
+  /* If INSN is an asm, and DEST is a hard register, reject, since it has
+     to be an explicit register variable, and was chosen for a reason.  */
+
+  if (GET_CODE (src) == ASM_OPERANDS
+      && GET_CODE (dest) == REG && REGNO (dest) < FIRST_PSEUDO_REGISTER)
+    return 0;
+
   /* If there are any volatile insns between INSN and I3, reject, because
      they might affect machine state.  */