re PR rtl-optimization/53908 (csa removes needed memory load)

	PR rtl-optimization/53908
	* df-problems.c (can_move_insns_across): When doing
	memory-reference book-keeping, handle call insns.

Co-Authored-By: Bernd Schmidt <bernds@codesourcery.com>
Co-Authored-By: Steven Bosscher <steven@gcc.gnu.org>

From-SVN: r189454

gcc/ChangeLog

+2012-07-13  Richard Sandiford  <rdsandiford@googlemail.com>
+	    Steven Bosscher  <steven@gcc.gnu.org>
+	    Bernd Schmidt  <bernds@codesourcery.com>
+
+	PR rtl-optimization/53908
+	* df-problems.c (can_move_insns_across): When doing
+	memory-reference book-keeping, handle call insns.
+
 2012-07-13  Richard Guenther  <rguenther@suse.de>
 
 	* gimple.c (gimple_types_compatible_p_1): Remove redundant

gcc/df-problems.c

@@ -4068,6 +4068,19 @@ can_move_insns_across (rtx from, rtx to, rtx across_from, rtx across_to,
 
   for (insn = across_to; ; insn = next)
     {
+      if (CALL_P (insn))
+	{
+	  if (RTL_CONST_OR_PURE_CALL_P (insn))
+	    /* Pure functions can read from memory.  Const functions can
+	       read from arguments that the ABI has forced onto the stack.
+	       Neither sort of read can be volatile.  */
+	    memrefs_in_across |= MEMREF_NORMAL;
+	  else
+	    {
+	      memrefs_in_across |= MEMREF_VOLATILE;
+	      mem_sets_in_across |= MEMREF_VOLATILE;
+	    }
+	}
       if (NONDEBUG_INSN_P (insn))
 	{
 	  memrefs_in_across |= for_each_rtx (&PATTERN (insn), find_memory,