* rtlanal.c (nonzero_bits1): Handle CLRSB.

From-SVN: r178101

* rtlanal.c (nonzero_bits1): Handle CLRSB.
From-SVN: r178101
8840ae2b · Jakub Jelinek · Jakub Jelinek · 321358d4 · 8840ae2b · 8840ae2b
Commit 8840ae2b authored Aug 26, 2011 by Jakub Jelinek Committed by Jakub Jelinek Aug 26, 2011
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Showing with 11 additions and 2 deletions

gcc/ChangeLog
+4 -0

gcc/rtlanal.c
+7 -2

No files found.
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
+2011-08-26  Jakub Jelinek  <jakub@redhat.com>
+
+	* rtlanal.c (nonzero_bits1): Handle CLRSB.
+
 2011-08-26  Richard Guenther  <rguenther@suse.de>

 	* expr.c (string_constant): Handle &MEM_REF.

--- a/gcc/rtlanal.c
+++ b/gcc/rtlanal.c
 /* Analyze RTL for GNU compiler.
   Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
-   1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
-   Free Software Foundation, Inc.
+   1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
+   2011 Free Software Foundation, Inc.

 This file is part of GCC.

@@ -4273,6 +4273,11 @@ nonzero_bits1 (const_rtx x, enum machine_mode mode, const_rtx known_x,
 	nonzero = -1;
      break;

+    case CLRSB:
+      /* This is at most the number of bits in the mode minus 1.  */
+      nonzero = ((unsigned HOST_WIDE_INT) 1 << (floor_log2 (mode_width))) - 1;
+      break;
+
    case PARITY:
      nonzero = 1;
      break;