linux-kernel - [PATCH next 7/7] minmax.h: Remove some #defines that are only expanded once

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Message-ID: <9386d1ebb8974fbabbed2635160c3975@AcuMS.aculab.com>
Date: Mon, 18 Nov 2024 19:15:51 +0000
From: David Laight <David.Laight@...LAB.COM>
To: Linus Torvalds <torvalds@...ux-foundation.org>
CC: 'Arnd Bergmann' <arnd@...nel.org>, "'linux-kernel@...r.kernel.org'"
	<linux-kernel@...r.kernel.org>, 'Jens Axboe' <axboe@...nel.dk>, "'Matthew
 Wilcox'" <willy@...radead.org>, 'Christoph Hellwig' <hch@...radead.org>,
	'Andrew Morton' <akpm@...ux-foundation.org>, 'Andy Shevchenko'
	<andriy.shevchenko@...ux.intel.com>, 'Dan Carpenter'
	<dan.carpenter@...aro.org>, "'Jason A . Donenfeld'" <Jason@...c4.com>,
	"'pedro.falcato@...il.com'" <pedro.falcato@...il.com>, 'Mateusz Guzik'
	<mjguzik@...il.com>, "'linux-mm@...ck.org'" <linux-mm@...ck.org>, "'Lorenzo
 Stoakes'" <lorenzo.stoakes@...cle.com>
Subject: [PATCH next 7/7] minmax.h: Remove some #defines that are only
 expanded once

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.

Signed-off-by: David Laight <david.laight@...lab.com>
---
 include/linux/minmax.h | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/include/linux/minmax.h b/include/linux/minmax.h
index 2bbdd5b5e07e..eaaf5c008e4d 100644
--- 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))
-- 
2.17.1

-
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