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minmax.h: reduce the #define expansion of min(), max() and clamp()

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Since the test for signed values being non-negative only relies on
__builtion_constant_p() (not is_constexpr()) it can use the 'ux' variable
instead of the caller supplied expression.  This means that the #define
parameters are only expanded twice.  Once in the code and once quoted in
the error message.

Link: https://lkml.kernel.org/r/051afc171806425da991908ed8688a98@AcuMS.aculab.com
Signed-off-by: David Laight <david.laight@aculab.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Pedro Falcato <pedro.falcato@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
David Laight 2024-11-18 19:12:50 +00:00 committed by Andrew Morton
parent db6a793477
commit 8f036e7731
1 changed files with 12 additions and 12 deletions
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24
include/linux/minmax.h
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@ -46,10 +46,10 @@
* comparison, and these expressions only need to be careful to not cause
* warnings for pointer use.
*/
#define __signed_type_use(x, ux) (2 + __is_nonneg(x, ux))
#define __unsigned_type_use(x, ux) (1 + 2 * (sizeof(ux) < 4))
#define __sign_use(x, ux) (is_signed_type(typeof(ux)) ? \
__signed_type_use(x, ux) : __unsigned_type_use(x, ux))
#define __signed_type_use(ux) (2 + __is_nonneg(ux))
#define __unsigned_type_use(ux) (1 + 2 * (sizeof(ux) < 4))
#define __sign_use(ux) (is_signed_type(typeof(ux)) ? \
__signed_type_use(ux) : __unsigned_type_use(ux))
/*
* Check whether a signed value is always non-negative.
@ -71,13 +71,13 @@
#else
#define __signed_type(ux) typeof(__builtin_choose_expr(sizeof(ux) > 4, 1LL, 1L))
#endif
#define __is_nonneg(x, ux) statically_true((__signed_type(ux))(x) >= 0)
#define __is_nonneg(ux) statically_true((__signed_type(ux))(ux) >= 0)
#define __types_ok(x, y, ux, uy) \
(__sign_use(x, ux) & __sign_use(y, uy))
#define __types_ok(ux, uy) \
(__sign_use(ux) & __sign_use(uy))
#define __types_ok3(x, y, z, ux, uy, uz) \
(__sign_use(x, ux) & __sign_use(y, uy) & __sign_use(z, uz))
#define __types_ok3(ux, uy, uz) \
(__sign_use(ux) & __sign_use(uy) & __sign_use(uz))
#define __cmp_op_min <
#define __cmp_op_max >
@ -92,7 +92,7 @@
#define __careful_cmp_once(op, x, y, ux, uy) ({ \
__auto_type ux = (x); __auto_type uy = (y); \
BUILD_BUG_ON_MSG(!__types_ok(x, y, ux, uy), \
BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \
#op"("#x", "#y") signedness error"); \
__cmp(op, ux, uy); })
@ -109,7 +109,7 @@
static_assert(__builtin_choose_expr(__is_constexpr((lo) > (hi)), \
(lo) <= (hi), true), \
"clamp() low limit " #lo " greater than high limit " #hi); \
BUILD_BUG_ON_MSG(!__types_ok3(val, lo, hi, uval, ulo, uhi), \
BUILD_BUG_ON_MSG(!__types_ok3(uval, ulo, uhi), \
"clamp("#val", "#lo", "#hi") signedness error"); \
__clamp(uval, ulo, uhi); })
@ -149,7 +149,7 @@
#define __careful_op3(op, x, y, z, ux, uy, uz) ({ \
__auto_type ux = (x); __auto_type uy = (y);__auto_type uz = (z);\
BUILD_BUG_ON_MSG(!__types_ok3(x, y, z, ux, uy, uz), \
BUILD_BUG_ON_MSG(!__types_ok3(ux, uy, uz), \
#op"3("#x", "#y", "#z") signedness error"); \
__cmp(op, ux, __cmp(op, uy, uz)); })