[PATCH 3/4] log2: allow use of is_power_of_2() in constant expressions

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From: Jani Nikula <jani.nikula@intel.com>
To: linux-kernel@vger.kernel.org
Cc: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
	jani.nikula@intel.com,
	"Andrew Morton" <akpm@linux-foundation.org>,
	"Christian König" <christian.koenig@amd.com>,
	"David Gow" <davidgow@google.com>
Subject: [PATCH 3/4] log2: allow use of is_power_of_2() in constant expressions
Date: Thu, 30 Mar 2023 13:42:42 +0300	[thread overview]
Message-ID: <20230330104243.2120761-4-jani.nikula@intel.com> (raw)
In-Reply-To: <20230330104243.2120761-1-jani.nikula@intel.com>

Even though the static inline functions are __attribute__((const)) you
can't use them in constant expressions. Make is_power_of_2() a constant
expression if possible.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christian König <christian.koenig@amd.com>
Cc: David Gow <davidgow@google.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
---
 include/linux/log2.h | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/include/linux/log2.h b/include/linux/log2.h
index 4027d1eecd7f..447a85102de0 100644
--- a/include/linux/log2.h
+++ b/include/linux/log2.h
@@ -56,9 +56,11 @@ bool __is_power_of_2(unsigned long n)
  * Return: true if @n is a power of 2, otherwise false.
  */
 #define is_power_of_2(n)						\
-	__builtin_choose_expr(sizeof(n) > sizeof(unsigned long),	\
-			      __is_power_of_2_ull(n),			\
-			      __is_power_of_2(n))
+	__builtin_choose_expr(__is_constexpr(n),			\
+			      __IS_POWER_OF_2(n),			\
+			      __builtin_choose_expr(sizeof(n) > sizeof(unsigned long), \
+						    __is_power_of_2_ull(n), \
+						    __is_power_of_2(n)))
 
 /**
  * __roundup_pow_of_two() - round up to nearest power of two
-- 
2.39.2

WARNING: multiple messages have this Message-ID (diff)

From: Jani Nikula <jani.nikula@intel.com>
To: linux-kernel@vger.kernel.org
Cc: jani.nikula@intel.com, intel-gfx@lists.freedesktop.org,
	dri-devel@lists.freedesktop.org,
	"David Gow" <davidgow@google.com>,
	"Andrew Morton" <akpm@linux-foundation.org>,
	"Christian König" <christian.koenig@amd.com>
Subject: [PATCH 3/4] log2: allow use of is_power_of_2() in constant expressions
Date: Thu, 30 Mar 2023 13:42:42 +0300	[thread overview]
Message-ID: <20230330104243.2120761-4-jani.nikula@intel.com> (raw)
In-Reply-To: <20230330104243.2120761-1-jani.nikula@intel.com>

Even though the static inline functions are __attribute__((const)) you
can't use them in constant expressions. Make is_power_of_2() a constant
expression if possible.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christian König <christian.koenig@amd.com>
Cc: David Gow <davidgow@google.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
---
 include/linux/log2.h | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/include/linux/log2.h b/include/linux/log2.h
index 4027d1eecd7f..447a85102de0 100644
--- a/include/linux/log2.h
+++ b/include/linux/log2.h
@@ -56,9 +56,11 @@ bool __is_power_of_2(unsigned long n)
  * Return: true if @n is a power of 2, otherwise false.
  */
 #define is_power_of_2(n)						\
-	__builtin_choose_expr(sizeof(n) > sizeof(unsigned long),	\
-			      __is_power_of_2_ull(n),			\
-			      __is_power_of_2(n))
+	__builtin_choose_expr(__is_constexpr(n),			\
+			      __IS_POWER_OF_2(n),			\
+			      __builtin_choose_expr(sizeof(n) > sizeof(unsigned long), \
+						    __is_power_of_2_ull(n), \
+						    __is_power_of_2(n)))
 
 /**
  * __roundup_pow_of_two() - round up to nearest power of two
-- 
2.39.2

WARNING: multiple messages have this Message-ID (diff)

From: Jani Nikula <jani.nikula@intel.com>
To: linux-kernel@vger.kernel.org
Cc: jani.nikula@intel.com, intel-gfx@lists.freedesktop.org,
	dri-devel@lists.freedesktop.org,
	"David Gow" <davidgow@google.com>,
	"Andrew Morton" <akpm@linux-foundation.org>,
	"Christian König" <christian.koenig@amd.com>
Subject: [Intel-gfx] [PATCH 3/4] log2: allow use of is_power_of_2() in constant expressions
Date: Thu, 30 Mar 2023 13:42:42 +0300	[thread overview]
Message-ID: <20230330104243.2120761-4-jani.nikula@intel.com> (raw)
In-Reply-To: <20230330104243.2120761-1-jani.nikula@intel.com>

Even though the static inline functions are __attribute__((const)) you
can't use them in constant expressions. Make is_power_of_2() a constant
expression if possible.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christian König <christian.koenig@amd.com>
Cc: David Gow <davidgow@google.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
---
 include/linux/log2.h | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/include/linux/log2.h b/include/linux/log2.h
index 4027d1eecd7f..447a85102de0 100644
--- a/include/linux/log2.h
+++ b/include/linux/log2.h
@@ -56,9 +56,11 @@ bool __is_power_of_2(unsigned long n)
  * Return: true if @n is a power of 2, otherwise false.
  */
 #define is_power_of_2(n)						\
-	__builtin_choose_expr(sizeof(n) > sizeof(unsigned long),	\
-			      __is_power_of_2_ull(n),			\
-			      __is_power_of_2(n))
+	__builtin_choose_expr(__is_constexpr(n),			\
+			      __IS_POWER_OF_2(n),			\
+			      __builtin_choose_expr(sizeof(n) > sizeof(unsigned long), \
+						    __is_power_of_2_ull(n), \
+						    __is_power_of_2(n)))
 
 /**
  * __roundup_pow_of_two() - round up to nearest power of two
-- 
2.39.2

next prev parent reply	other threads:[~2023-03-30 10:43 UTC|newest]

Thread overview: 41+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-30 10:42 [PATCH 0/4] log2: make is_power_of_2() more generic Jani Nikula
2023-03-30 10:42 ` [Intel-gfx] " Jani Nikula
2023-03-30 10:42 ` Jani Nikula
2023-03-30 10:42 ` [PATCH 1/4] log2: add helper __IS_POWER_OF_2() Jani Nikula
2023-03-30 10:42   ` [Intel-gfx] " Jani Nikula
2023-03-30 10:42   ` Jani Nikula
2023-03-30 10:42 ` [PATCH 2/4] log2: have is_power_of_2() support bigger types than unsigned long Jani Nikula
2023-03-30 10:42   ` [Intel-gfx] " Jani Nikula
2023-03-30 10:42   ` Jani Nikula
2023-03-30 10:42 ` Jani Nikula [this message]
2023-03-30 10:42   ` [Intel-gfx] [PATCH 3/4] log2: allow use of is_power_of_2() in constant expressions Jani Nikula
2023-03-30 10:42   ` Jani Nikula
2023-03-30 10:42 ` [PATCH 4/4] drm/i915/reg: use is_power_of_2() from log2.h Jani Nikula
2023-03-30 10:42   ` [Intel-gfx] " Jani Nikula
2023-03-30 10:42   ` Jani Nikula
2023-03-30 10:59 ` [PATCH 0/4] log2: make is_power_of_2() more generic Christian König
2023-03-30 10:59   ` [Intel-gfx] " Christian König
2023-03-30 10:59   ` Christian König
2023-03-30 11:10 ` [Intel-gfx] ✗ Fi.CI.CHECKPATCH: warning for " Patchwork
2023-03-30 11:10 ` [Intel-gfx] ✗ Fi.CI.SPARSE: " Patchwork
2023-03-30 11:23 ` [Intel-gfx] ✓ Fi.CI.BAT: success " Patchwork
2023-03-30 19:50 ` [PATCH 0/4] " Andrew Morton
2023-03-30 19:50   ` [Intel-gfx] " Andrew Morton
2023-03-30 19:50   ` Andrew Morton
2023-03-30 21:53   ` David Laight
2023-03-30 21:53     ` [Intel-gfx] " David Laight
2023-03-30 21:53     ` David Laight
2023-03-30 22:18     ` Andrew Morton
2023-03-30 22:18       ` Andrew Morton
2023-03-30 22:18       ` [Intel-gfx] " Andrew Morton
2023-03-31  7:33       ` David Laight
2023-03-31  7:33         ` [Intel-gfx] " David Laight
2023-03-31  7:33         ` David Laight
2023-03-31  8:31       ` Jani Nikula
2023-03-31  8:31         ` [Intel-gfx] " Jani Nikula
2023-03-31  8:31         ` Jani Nikula
2023-04-05 15:27         ` Steven Price
2023-04-05 15:27           ` [Intel-gfx] " Steven Price
2023-04-05 15:27           ` Steven Price
2024-04-12 10:01           ` Jani Nikula
2023-03-31  5:58 ` [Intel-gfx] ✓ Fi.CI.IGT: success for " Patchwork

find likely ancestor, descendant, or conflicting patches for this message:
dfblob:4027d1eecd7 dfblob:4027d1eecd7 dfblob:4027d1eecd7
dfblob:447a85102de dfblob:447a85102de dfblob:447a85102de
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