From: Javier Pello <devel@otheo.eu>
To: libc-alpha@sourceware.org
Subject: [PATCH 2/4] elf: Simplify hwcaps masked value bit counting
Date: Mon, 5 Sep 2022 20:10:27 +0200 [thread overview]
Message-ID: <20220905201027.0338ebf933cfd767cfa83da3@otheo.eu> (raw)
In-Reply-To: <20220905200652.d69204581d15c64647da5cd2@otheo.eu>
Use a simpler way to count the number of bits set in the masked
value in _dl_important_hwcaps.
Signed-off-by: Javier Pello <devel@otheo.eu>
---
elf/dl-hwcaps.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/elf/dl-hwcaps.c b/elf/dl-hwcaps.c
index 92eb5379..8f11a18f 100644
--- a/elf/dl-hwcaps.c
+++ b/elf/dl-hwcaps.c
@@ -197,8 +197,8 @@ _dl_important_hwcaps (const char *glibc_hwcaps_prepend,
+ hwcaps_counts.total_length);
/* Count the number of bits set in the masked value. */
- for (n = 0; (~((1ULL << n) - 1) & masked) != 0; ++n)
- if ((masked & (1ULL << n)) != 0)
+ for (uint64_t mm = masked; mm != 0; mm >>= 1)
+ if ((mm & 1ULL) != 0)
++cnt;
/* For TLS enabled builds always add 'tls'. */
--
2.36.0
next prev parent reply other threads:[~2022-09-05 18:11 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-05 18:06 [PATCH 0/4] elf: Fix hwcaps string size overestimation Javier Pello
2022-09-05 18:09 ` [PATCH 1/4] " Javier Pello
2022-09-08 10:15 ` Florian Weimer
2022-09-05 18:10 ` Javier Pello [this message]
2022-09-05 18:12 ` [PATCH 3/4] elf: Remove unneeded conditional in _dl_important_hwcaps Javier Pello
2022-09-05 18:13 ` [PATCH 4/4] elf: Simplify hwcaps power set string construction Javier Pello
2022-09-06 7:35 ` [PATCH 0/4] elf: Fix hwcaps string size overestimation Florian Weimer
2022-09-06 18:12 ` Javier Pello
2022-09-08 11:23 ` Florian Weimer
2022-09-14 18:07 ` [PATCH 0/6] Remove legacy hwcaps support Javier Pello
2022-09-14 18:08 ` [PATCH 1/6] elf: Remove legacy hwcaps support from the dynamic loader Javier Pello
2022-09-14 18:10 ` [PATCH 2/6] elf: Remove legacy hwcaps support from ldconfig Javier Pello
2022-09-14 18:10 ` [PATCH 3/6] elf: Remove hwcap parameter from add_to_cache signature Javier Pello
2022-09-14 18:12 ` [PATCH 4/6] elf: Remove hwcap and bits_hwcap fields from struct cache_entry Javier Pello
2022-09-14 18:13 ` [PATCH 5/6] elf: Remove _dl_string_hwcap Javier Pello
2022-09-14 18:15 ` [PATCH 6/6] elf: Simplify output of hwcap subdirectories in ld.so help Javier Pello
2022-09-15 8:42 ` Carlos O'Donell
2022-09-15 19:12 ` Javier Pello
2022-09-14 21:23 ` [PATCH 0/6] Remove legacy hwcaps support Joseph Myers
2022-09-17 14:17 ` [PATCH v2 " Javier Pello
2022-09-17 14:18 ` [PATCH v2 1/6] elf: Remove legacy hwcaps support from the dynamic loader Javier Pello
2022-09-22 11:46 ` Florian Weimer
2022-09-17 14:19 ` [PATCH v2 2/6] elf: Remove legacy hwcaps support from ldconfig Javier Pello
2022-09-22 12:14 ` Florian Weimer
2022-09-17 14:20 ` [PATCH v2 3/6] elf: Remove hwcap parameter from add_to_cache signature Javier Pello
2022-09-22 16:02 ` Florian Weimer
2022-09-17 14:22 ` [PATCH v2 4/6] elf: Remove hwcap and bits_hwcap fields from struct cache_entry Javier Pello
2022-09-22 16:03 ` Florian Weimer
2022-09-17 14:23 ` [PATCH v2 5/6] elf: Remove _dl_string_hwcap Javier Pello
2022-09-17 14:24 ` [PATCH v2 6/6] elf: Simplify output of hwcap subdirectories in ld.so help Javier Pello
2022-09-21 16:26 ` [PATCH v2 0/6] Remove legacy hwcaps support Joseph Myers
2022-09-27 18:03 ` [PATCH v3 0/8] " Javier Pello
2022-09-27 18:05 ` [PATCH v3 1/8] x86_64: Remove platform directory library loading test Javier Pello
2022-10-03 14:56 ` Adhemerval Zanella Netto
2022-10-04 17:53 ` Javier Pello
2022-10-04 17:59 ` Adhemerval Zanella Netto
2022-09-27 18:05 ` [PATCH v3 2/8] elf: Remove legacy hwcaps support from the dynamic loader Javier Pello
2022-09-27 18:06 ` [PATCH v3 3/8] elf: Remove legacy hwcaps support from ldconfig Javier Pello
2022-10-03 15:31 ` Adhemerval Zanella Netto
2022-09-27 18:07 ` [PATCH v3 4/8] elf: Remove hwcap parameter from add_to_cache signature Javier Pello
2022-09-27 18:08 ` [PATCH v3 5/8] elf: Remove hwcap and bits_hwcap fields from struct cache_entry Javier Pello
2022-09-27 18:08 ` [PATCH v3 6/8] Add NEWS entry for legacy hwcaps removal Javier Pello
2022-10-03 15:44 ` Adhemerval Zanella Netto
2022-10-03 19:29 ` Andreas Schwab
2022-10-03 19:49 ` Adhemerval Zanella Netto
2022-10-03 19:59 ` Florian Weimer
2022-10-04 18:00 ` Adhemerval Zanella Netto
2022-10-05 18:12 ` Javier Pello
2022-10-06 11:03 ` Adhemerval Zanella Netto
2022-09-27 18:09 ` [PATCH v3 7/8] elf: Remove _dl_string_hwcap Javier Pello
2022-10-03 16:52 ` Adhemerval Zanella Netto
2022-09-27 18:10 ` [PATCH v3 8/8] elf: Simplify output of hwcap subdirectories in ld.so help Javier Pello
2022-10-03 17:02 ` Adhemerval Zanella Netto
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