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From: David Laight <David.Laight@ACULAB.COM>
To: "'linux-kernel@vger.kernel.org'" <linux-kernel@vger.kernel.org>, "'Linus
 Torvalds'" <torvalds@linux-foundation.org>, 'Netdev'
	<netdev@vger.kernel.org>, "'dri-devel@lists.freedesktop.org'"
	<dri-devel@lists.freedesktop.org>
CC: 'Andy Shevchenko' <andriy.shevchenko@linux.intel.com>, 'Andrew Morton'
	<akpm@linux-foundation.org>, "'Matthew Wilcox (Oracle)'"
	<willy@infradead.org>, 'Christoph Hellwig' <hch@infradead.org>, "'Dan
 Carpenter'" <dan.carpenter@linaro.org>, 'Linus Walleij'
	<linus.walleij@linaro.org>, "'David S . Miller'" <davem@davemloft.net>,
	"'linux-btrfs@vger.kernel.org'" <linux-btrfs@vger.kernel.org>, 'Jens Axboe'
	<axboe@kernel.dk>
Subject: RE: [PATCH next 05/11] minmax: Move the signedness check out of
 __cmp_once() and __clamp_once()
Thread-Topic: [PATCH next 05/11] minmax: Move the signedness check out of
 __cmp_once() and __clamp_once()
Thread-Index: AdpSIGH+4MQss22qSoGjj8lEgu0knw==
Date: Sun, 28 Jan 2024 19:29:45 +0000
Message-ID: <a6b280993ac5448fa75f226262893f89@AcuMS.aculab.com>
References: <0ca26166dd2a4ff5a674b84704ff1517@AcuMS.aculab.com>
In-Reply-To: <0ca26166dd2a4ff5a674b84704ff1517@AcuMS.aculab.com>
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There is no need to do the signedness/type check when the arguments
are being cast to a fixed type.
So move the check out of __xxx_once() into __careful_xxx().

Signed-off-by: David Laight <david.laight@aculab.com>
---
 include/linux/minmax.h | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/include/linux/minmax.h b/include/linux/minmax.h
index 8ee003d8abaf..111c52a14fe5 100644
--- a/include/linux/minmax.h
+++ b/include/linux/minmax.h
@@ -46,14 +46,14 @@
 #define __cmp_once(op, x, y, uniq) ({=09=09\
 =09typeof(x) __x_##uniq =3D (x);=09=09\
 =09typeof(y) __y_##uniq =3D (y);=09=09\
-=09_Static_assert(__types_ok(x, y),=09\
-=09=09#op "(" #x ", " #y ") signedness error, fix types or consider u" #op=
 "() before " #op "_t()"); \
 =09__cmp(op, __x_##uniq, __y_##uniq); })
=20
 #define __careful_cmp(op, x, y, uniq)=09=09=09=09\
 =09__builtin_choose_expr(__is_constexpr((x) - (y)),=09\
 =09=09__cmp(op, x, y),=09=09=09=09\
-=09=09__cmp_once(op, x, y, uniq))
+=09=09({ _Static_assert(__types_ok(x, y),=09=09\
+=09=09=09#op "(" #x ", " #y ") signedness error, fix types or consider u" =
#op "() before " #op "_t()"); \
+=09=09__cmp_once(op, x, y, uniq); }))
=20
 /**
  * min - return minimum of two values of the same or compatible types
@@ -139,14 +139,14 @@
 =09_Static_assert(__builtin_choose_expr(__is_constexpr((lo) > (hi)),=09\
 =09=09=09(lo) <=3D (hi), true),=09=09=09=09=09\
 =09=09"clamp() low limit " #lo " greater than high limit " #hi);=09\
-=09_Static_assert(__types_ok(val, lo), "clamp() 'lo' signedness error");=
=09\
-=09_Static_assert(__types_ok(val, hi), "clamp() 'hi' signedness error");=
=09\
 =09__clamp(__val_##uniq, __lo_##uniq, __hi_##uniq); })
=20
-#define __careful_clamp(val, lo, hi, uniq) ({=09=09=09=09\
+#define __careful_clamp(val, lo, hi, uniq)=09=09=09=09\
 =09__builtin_choose_expr(__is_constexpr((val) - (lo) + (hi)),=09\
 =09=09__clamp(val, lo, hi),=09=09=09=09=09\
-=09=09__clamp_once(val, lo, hi, uniq)); })
+=09=09({ _Static_assert(__types_ok(val, lo), "clamp() 'lo' signedness erro=
r");=09\
+=09=09_Static_assert(__types_ok(val, hi), "clamp() 'hi' signedness error")=
;=09\
+=09=09__clamp_once(val, lo, hi, uniq); }))
=20
 /**
  * clamp - return a value clamped to a given range with strict typecheckin=
g
--=20
2.17.1

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