This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]
Other format:	[Raw text]

Re: [wide-int] Fix exact_log2 zext test

From: Kenneth Zadeck <zadeck at naturalbridge dot com>
To: gcc-patches at gcc dot gnu dot org, mikestump at comcast dot net, rdsandiford at googlemail dot com
Date: Sat, 02 Nov 2013 09:39:05 -0400
Subject: Re: [wide-int] Fix exact_log2 zext test
Authentication-results: sourceware.org; auth=none
References: <87fvrfksw8 dot fsf at talisman dot default>

On 11/02/2013 06:19 AM, Richard Sandiford wrote:

...which I'd fluffed when doing the wi:: conversion.

Tested on powerpc64-linux-gnu and x86_64-linux-gnu.  It fixed a spurious
gcc.dg difference on alpha-linux-gnu.  Applied as obvious.

Thanks,
Richard


Index: gcc/wide-int.cc
===================================================================
--- gcc/wide-int.cc	(revision 204311)
+++ gcc/wide-int.cc	(working copy)
@@ -2044,7 +2044,7 @@

/* Get a zero-extended form of block CRUX. */

    unsigned HOST_WIDE_INT hwi = x.val[crux];
-  if (crux * HOST_BITS_PER_WIDE_INT > x.precision)
+  if ((crux + 1) * HOST_BITS_PER_WIDE_INT > x.precision)
      hwi = zext_hwi (hwi, x.precision % HOST_BITS_PER_WIDE_INT);

/* Now it's down to whether HWI is a power of 2. */

ok by me.

kenny

References:
- [wide-int] Fix exact_log2 zext test
  - From: Richard Sandiford

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]