From: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
To: linux-sparse@vger.kernel.org
Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Subject: [PATCH 3/6] add helper is_power_of_2()
Date: Fri, 27 Nov 2020 23:25:12 +0100 [thread overview]
Message-ID: <20201127222516.44915-4-luc.vanoostenryck@gmail.com> (raw)
In-Reply-To: <20201127222516.44915-1-luc.vanoostenryck@gmail.com>
Add is_power_of_2() to test if a value is a power of 2.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
---
bits.h | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/bits.h b/bits.h
index c0dc952eaed9..63a663c248e4 100644
--- a/bits.h
+++ b/bits.h
@@ -58,4 +58,9 @@ static inline long long bits_extend(long long val, unsigned size, int is_signed)
return val;
}
+static inline int is_power_of_2(long long val)
+{
+ return val && !(val & (val - 1));
+}
+
#endif
--
2.29.2
next prev parent reply other threads:[~2020-11-27 22:32 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-22 15:27 [PATCH 0/7] simplify logical negation Luc Van Oostenryck
2020-11-22 15:27 ` [PATCH 1/7] not: add testcases for canonicalization & simplification of negations Luc Van Oostenryck
2020-11-22 19:00 ` Linus Torvalds
2020-11-22 19:57 ` Luc Van Oostenryck
2020-11-22 20:13 ` Linus Torvalds
2020-11-22 20:38 ` Luc Van Oostenryck
2020-11-22 22:26 ` Luc Van Oostenryck
2020-11-27 22:25 ` [PATCH 0/6] 'bits translation' simplification Luc Van Oostenryck
2020-11-27 22:25 ` [PATCH 1/6] add testscases for 'bits translation' optimization Luc Van Oostenryck
2020-11-27 22:25 ` [PATCH 2/6] factorize SEL(x, OP(y,z), y) into OP(SEL(x, z, 0), y) Luc Van Oostenryck
2020-11-27 22:25 ` Luc Van Oostenryck [this message]
2020-11-27 22:25 ` [PATCH 4/6] add helper is_pow2() Luc Van Oostenryck
2020-11-27 22:25 ` [PATCH 5/6] add log base 2 function: log2_exact() Luc Van Oostenryck
2020-11-27 22:25 ` [PATCH 6/6] convert SEL(x & BIT1, BIT2, 0) into SHIFT(x & BIT1, S) Luc Van Oostenryck
2020-11-27 22:25 ` [PATCH 7/7] move up instructions blocking if-conversion Luc Van Oostenryck
2020-11-27 22:44 ` [PATCH 0/6] 'bits translation' simplification Linus Torvalds
2020-11-22 15:27 ` [PATCH 2/7] canon: put PSEUDO_ARGs in canonical order too Luc Van Oostenryck
2020-11-22 15:27 ` [PATCH 3/7] canon: put PSEUDO_REGs " Luc Van Oostenryck
2020-11-22 15:27 ` [PATCH 4/7] canon: simplify calculation of canonical order Luc Van Oostenryck
2020-11-22 15:27 ` [PATCH 5/7] opcode: add helpers opcode_negate() & opcode_swap() Luc Van Oostenryck
2020-11-22 15:27 ` [PATCH 6/7] not: simplify (~x {&,|,^} x) --> {0,~0,~0} Luc Van Oostenryck
2020-11-22 15:27 ` [PATCH 7/7] not: simplify ((x cmp y) {&,|,^} (x !cmp y)) --> {0,1,1} Luc Van Oostenryck
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