[PATCH] perf: fix bug in isupper() and islower()

[PATCH] perf: fix bug in isupper() and islower()

[Sukadev Bhattiprolu]

>From fd349681226bf7b27c9d0f72b0f3941b5aa94f78 Mon Sep 17 00:00:00 2001
From: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Date: Fri, 29 Mar 2013 12:14:43 -0700
Subject: [PATCH] perf: fix bug in isupper() and islower()

One of the reasons 'perf test' is failing on Power appears to be due to
a bug in isupper().

isupper(c) and islower(c) should be checking 'c' against the mask 0x20.
Instead they are checking sane_ctype[c] which causes isupper() to be true
for lower case letters.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
---
 tools/perf/util/util.h |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index 09b4c26..2795ef6 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -219,8 +219,8 @@ extern unsigned char sane_ctype[256];
 #define isalpha(x) sane_istest(x,GIT_ALPHA)
 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
 #define isprint(x) sane_istest(x,GIT_PRINT)
-#define islower(x) (sane_istest(x,GIT_ALPHA) && sane_istest(x,0x20))
-#define isupper(x) (sane_istest(x,GIT_ALPHA) && !sane_istest(x,0x20))
+#define islower(x) (sane_istest(x,GIT_ALPHA) && (x & 0x20))
+#define isupper(x) (sane_istest(x,GIT_ALPHA) && !(x & 0x20))
 #define tolower(x) sane_case((unsigned char)(x), 0x20)
 #define toupper(x) sane_case((unsigned char)(x), 0)
 
-- 
1.7.1

Re: [PATCH] perf: fix bug in isupper() and islower()

[Namhyung Kim]

Hi Sukadev,

On Fri, 29 Mar 2013 12:29:50 -0700, Sukadev Bhattiprolu wrote:
> From fd349681226bf7b27c9d0f72b0f3941b5aa94f78 Mon Sep 17 00:00:00 2001
> From: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
> Date: Fri, 29 Mar 2013 12:14:43 -0700
> Subject: [PATCH] perf: fix bug in isupper() and islower()
>
> One of the reasons 'perf test' is failing on Power appears to be due to
> a bug in isupper().
>
> isupper(c) and islower(c) should be checking 'c' against the mask 0x20.
> Instead they are checking sane_ctype[c] which causes isupper() to be true
> for lower case letters.

Indeed!

Acked-by: Namhyung Kim <namhyung@kernel.org>

Thanks,
Namhyung

>
> Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
> ---
>  tools/perf/util/util.h |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
> index 09b4c26..2795ef6 100644
> --- a/tools/perf/util/util.h
> +++ b/tools/perf/util/util.h
> @@ -219,8 +219,8 @@ extern unsigned char sane_ctype[256];
>  #define isalpha(x) sane_istest(x,GIT_ALPHA)
>  #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
>  #define isprint(x) sane_istest(x,GIT_PRINT)
> -#define islower(x) (sane_istest(x,GIT_ALPHA) && sane_istest(x,0x20))
> -#define isupper(x) (sane_istest(x,GIT_ALPHA) && !sane_istest(x,0x20))
> +#define islower(x) (sane_istest(x,GIT_ALPHA) && (x & 0x20))
> +#define isupper(x) (sane_istest(x,GIT_ALPHA) && !(x & 0x20))
>  #define tolower(x) sane_case((unsigned char)(x), 0x20)
>  #define toupper(x) sane_case((unsigned char)(x), 0)

Re: [PATCH] perf: fix bug in isupper() and islower()

[Arnaldo Carvalho de Melo]

Em Mon, Apr 01, 2013 at 03:19:28PM +0900, Namhyung Kim escreveu:
> On Fri, 29 Mar 2013 12:29:50 -0700, Sukadev Bhattiprolu wrote:
> > Subject: [PATCH] perf: fix bug in isupper() and islower()

> > One of the reasons 'perf test' is failing on Power appears to be due to
> > a bug in isupper().

> > isupper(c) and islower(c) should be checking 'c' against the mask 0x20.
> > Instead they are checking sane_ctype[c] which causes isupper() to be true
> > for lower case letters.

> Indeed!
> Acked-by: Namhyung Kim <namhyung@kernel.org>

But can we try to use the same defs as for the kernel? Or at least sync
this code against git.git, that is where it comes from?

There we have:

#define islower(x) sane_iscase(x, 1)
#define isupper(x) sane_iscase(x, 0)

#define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)

static inline int sane_iscase(int x, int is_lower)
{
        if (!sane_istest(x, GIT_ALPHA))
                return 0;

        if (is_lower)
                return (x & 0x20) != 0;
        else
                return (x & 0x20) == 0;
}
----------------------------------------------------------------------------

In the kernel we have instead:

include/linux/ctype.h

#define _U      0x01    /* upper */
#define __ismask(x) (_ctype[(int)(unsigned char)(x)])
#define isupper(c)      ((__ismask(c)&(_U)) != 0)

----------------------------------------------------------------------------

I'm merging this fix now, as it improves things, but this seemingly
needless speciations looks insane, would be great to have at least
tools/perf/  using the same stuff as its landlord, the kernel.

- Arnaldo

[tip:perf/core] perf tools: Fix bug in isupper() and islower()

[tip-bot for Sukadev Bhattiprolu]

Commit-ID:  6956664a5c4c32d5aa48fe96d5e2421a3e3f72d5
Gitweb:     http://git.kernel.org/tip/6956664a5c4c32d5aa48fe96d5e2421a3e3f72d5
Author:     Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
AuthorDate: Fri, 29 Mar 2013 12:14:43 -0700
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Tue, 28 May 2013 16:23:51 +0300

perf tools: Fix bug in isupper() and islower()

One of the reasons 'perf test' is failing on Power appears to be due to
a bug in isupper().

isupper(c) and islower(c) should be checking 'c' against the mask 0x20.
Instead they are checking sane_ctype[c] which causes isupper() to be
true for lower case letters.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20130329192950.GA9312@us.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/util.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index a45710b..7a484c9 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -221,8 +221,8 @@ extern unsigned char sane_ctype[256];
 #define isalpha(x) sane_istest(x,GIT_ALPHA)
 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
 #define isprint(x) sane_istest(x,GIT_PRINT)
-#define islower(x) (sane_istest(x,GIT_ALPHA) && sane_istest(x,0x20))
-#define isupper(x) (sane_istest(x,GIT_ALPHA) && !sane_istest(x,0x20))
+#define islower(x) (sane_istest(x,GIT_ALPHA) && (x & 0x20))
+#define isupper(x) (sane_istest(x,GIT_ALPHA) && !(x & 0x20))
 #define tolower(x) sane_case((unsigned char)(x), 0x20)
 #define toupper(x) sane_case((unsigned char)(x), 0)