minmax.h: remove some #defines that are only expanded once

Eliav Farber farbere at amazon.com
Fri Oct 17 20:05:19 AEDT 2025


From: David Laight <David.Laight at ACULAB.COM>

[ Upstream commit 2b97aaf74ed534fb838d09867d09a3ca5d795208 ]

The bodies of __signed_type_use() and __unsigned_type_use() are much the
same size as their names - so put the bodies in the only line that expands
them.

Similarly __signed_type() is defined separately for 64bit and then used
exactly once just below.

Change the test for __signed_type from CONFIG_64BIT to one based on gcc
defined macros so that the code is valid if it gets used outside of a
kernel build.

Link: https://lkml.kernel.org/r/9386d1ebb8974fbabbed2635160c3975@AcuMS.aculab.com
Signed-off-by: David Laight <david.laight at aculab.com>
Cc: Andy Shevchenko <andriy.shevchenko at linux.intel.com>
Cc: Arnd Bergmann <arnd at kernel.org>
Cc: Christoph Hellwig <hch at infradead.org>
Cc: Dan Carpenter <dan.carpenter at linaro.org>
Cc: Jason A. Donenfeld <Jason at zx2c4.com>
Cc: Jens Axboe <axboe at kernel.dk>
Cc: Lorenzo Stoakes <lorenzo.stoakes at oracle.com>
Cc: Mateusz Guzik <mjguzik at gmail.com>
Cc: Matthew Wilcox <willy at infradead.org>
Cc: Pedro Falcato <pedro.falcato at gmail.com>
Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
Signed-off-by: Eliav Farber <farbere at amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
 include/linux/minmax.h |   14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

--- a/include/linux/minmax.h
+++ b/include/linux/minmax.h
@@ -46,10 +46,8 @@
  * comparison, and these expressions only need to be careful to not cause
  * warnings for pointer use.
  */
-#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))
+	(2 + __is_nonneg(ux)) : (1 + 2 * (sizeof(ux) < 4)))
 
 /*
  * Check whether a signed value is always non-negative.
@@ -57,7 +55,7 @@
  * A cast is needed to avoid any warnings from values that aren't signed
  * integer types (in which case the result doesn't matter).
  *
- * On 64-bit any integer or pointer type can safely be cast to 'long'.
+ * On 64-bit any integer or pointer type can safely be cast to 'long long'.
  * But on 32-bit we need to avoid warnings about casting pointers to integers
  * of different sizes without truncating 64-bit values so 'long' or 'long long'
  * must be used depending on the size of the value.
@@ -66,12 +64,12 @@
  * them, but we do not use s128 types in the kernel (we do use 'u128',
  * but they are handled by the !is_signed_type() case).
  */
-#ifdef CONFIG_64BIT
-  #define __signed_type(ux) long
+#if __SIZEOF_POINTER__ == __SIZEOF_LONG_LONG__
+#define __is_nonneg(ux) statically_true((long long)(ux) >= 0)
 #else
-  #define __signed_type(ux) typeof(__builtin_choose_expr(sizeof(ux) > 4, 1LL, 1L))
+#define __is_nonneg(ux) statically_true( \
+	(typeof(__builtin_choose_expr(sizeof(ux) > 4, 1LL, 1L)))(ux) >= 0)
 #endif
-#define __is_nonneg(ux) statically_true((__signed_type(ux))(ux) >= 0)
 
 #define __types_ok(ux, uy) \
 	(__sign_use(ux) & __sign_use(uy))


Patches currently in stable-queue which might be from farbere at amazon.com are

queue-5.10/minmax-allow-comparisons-of-int-against-unsigned-char-short.patch
queue-5.10/minmax-add-a-few-more-min_t-max_t-users.patch
queue-5.10/minmax-improve-macro-expansion-and-type-checking.patch
queue-5.10/minmax-fix-indentation-of-__cmp_once-and-__clamp_once.patch
queue-5.10/minmax.h-simplify-the-variants-of-clamp.patch
queue-5.10/minmax-add-in_range-macro.patch
queue-5.10/minmax.h-move-all-the-clamp-definitions-after-the-min-max-ones.patch
queue-5.10/minmax-allow-min-max-clamp-if-the-arguments-have-the-same-signedness.patch
queue-5.10/minmax-don-t-use-max-in-situations-that-want-a-c-constant-expression.patch
queue-5.10/minmax.h-remove-some-defines-that-are-only-expanded-once.patch
queue-5.10/minmax.h-use-build_bug_on_msg-for-the-lo-hi-test-in-clamp.patch
queue-5.10/minmax-simplify-min-max-clamp-implementation.patch
queue-5.10/minmax-deduplicate-__unconst_integer_typeof.patch
queue-5.10/minmax-simplify-and-clarify-min_t-max_t-implementation.patch
queue-5.10/minmax.h-add-whitespace-around-operators-and-after-commas.patch
queue-5.10/minmax-sanity-check-constant-bounds-when-clamping.patch
queue-5.10/minmax-avoid-overly-complicated-constant-expressions-in-vm-code.patch
queue-5.10/minmax-make-generic-min-and-max-macros-available-everywhere.patch
queue-5.10/minmax-fix-up-min3-and-max3-too.patch
queue-5.10/minmax.h-reduce-the-define-expansion-of-min-max-and-clamp.patch
queue-5.10/minmax-fix-header-inclusions.patch
queue-5.10/minmax-introduce-min-max-_array.patch
queue-5.10/btrfs-remove-duplicated-in_range-macro.patch
queue-5.10/overflow-tracing-define-the-is_signed_type-macro-once.patch
queue-5.10/minmax-relax-check-to-allow-comparison-between-unsigned-arguments-and-signed-constants.patch
queue-5.10/minmax-clamp-more-efficiently-by-avoiding-extra-comparison.patch
queue-5.10/minmax.h-update-some-comments.patch


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