mailing list of musl libc
 help / color / mirror / code / Atom feed
From: Alexander Monakov <amonakov@ispras.ru>
To: musl@lists.openwall.com
Cc: Alexander Monakov <amonakov@ispras.ru>
Subject: [PATCH 3/5] dynlink.c: slim down gnu_lookup
Date: Wed, 24 Jun 2015 02:24:53 +0300	[thread overview]
Message-ID: <1435101895-18240-4-git-send-email-amonakov@ispras.ru> (raw)
In-Reply-To: <1435101895-18240-1-git-send-email-amonakov@ispras.ru>

Do not reference dso->syms and dso-strings until point of use.
Check 'h1 == (h2|1)', the simplest condition, before the others.
---
 src/ldso/dynlink.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c
index 99dadd4..28812ef 100644
--- a/src/ldso/dynlink.c
+++ b/src/ldso/dynlink.c
@@ -237,24 +237,20 @@ static Sym *sysv_lookup(const char *s, uint32_t h, struct dso *dso)
 
 static Sym *gnu_lookup(const char *s, uint32_t h1, struct dso *dso)
 {
-	Sym *syms = dso->syms;
-	char *strings = dso->strings;
 	uint32_t *hashtab = dso->ghashtab;
 	uint32_t nbuckets = hashtab[0];
 	uint32_t *buckets = hashtab + 4 + hashtab[2]*(sizeof(size_t)/4);
-	uint32_t h2;
-	uint32_t *hashval;
 	uint32_t i = buckets[umod(h1, nbuckets, &dso->gudiv)];
 
 	if (!i) return 0;
 
-	hashval = buckets + nbuckets + (i - hashtab[1]);
+	uint32_t *hashval = buckets + nbuckets + (i - hashtab[1]);
 
 	for (h1 |= 1; ; i++) {
-		h2 = *hashval++;
-		if ((!dso->versym || dso->versym[i] >= 0)
-		    && (h1 == (h2|1)) && !strcmp(s, strings + syms[i].st_name))
-			return syms+i;
+		uint32_t h2 = *hashval++;
+		if ((h1 == (h2|1)) && (!dso->versym || dso->versym[i] >= 0)
+		    && !strcmp(s, dso->strings + dso->syms[i].st_name))
+			return dso->syms+i;
 		if (h2 & 1) break;
 	}
 


  parent reply	other threads:[~2015-06-23 23:24 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-06-23 23:24 [PATCH 0/5] gnu-hash speedups Alexander Monakov
2015-06-23 23:24 ` [PATCH 1/5] dynlink.c: use bloom filter in gnu hash lookup Alexander Monakov
2015-06-24  5:39   ` Rich Felker
2015-06-24  6:29     ` Alexander Monakov
2015-06-24  6:32       ` Alexander Monakov
2015-06-24  6:50       ` Rich Felker
2015-06-23 23:24 ` [PATCH 2/5] dynlink.c: compute modulus via magic multiplication Alexander Monakov
2015-06-24  4:18   ` Alexander Monakov
2015-06-24  4:19     ` Rich Felker
2015-06-24  4:24   ` Rich Felker
2015-06-24  4:32     ` Alexander Monakov
2015-06-24  5:13       ` Rich Felker
2015-06-24  6:08         ` Alexander Monakov
2015-06-24  6:39           ` Rich Felker
2015-06-23 23:24 ` Alexander Monakov [this message]
2015-06-23 23:24 ` [PATCH 4/5] dynlink.c: pass gnu-hash table pointer to gnu_lookup Alexander Monakov
2015-06-23 23:24 ` [PATCH 5/5] dynlink.c: use a faster expression in gnu_hash Alexander Monakov
2015-06-27 23:48 ` [PATCH v2 0/6] gnu-hash speedups Alexander Monakov
2015-06-27 23:48   ` [PATCH v2 1/6] dynlink.c: use a faster expression in gnu_hash Alexander Monakov
2015-06-27 23:48   ` [PATCH v2 2/6] dynlink.c: use bloom filter in gnu hash lookup Alexander Monakov
2015-06-27 23:48   ` [PATCH v2 3/6] dynlink.c: slim down gnu_lookup Alexander Monakov
2015-06-27 23:48   ` [PATCH v2 4/6] dynlink.c: pass gnu-hash table pointer to gnu_lookup Alexander Monakov
2015-06-28  0:05     ` Alexander Monakov
2015-06-28  8:59       ` Alexander Monakov
2015-06-27 23:48   ` [PATCH v2 5/6] dynlink.c: compute modulus via magic multiplication Alexander Monakov
2015-06-30 17:51     ` Rich Felker
2015-06-27 23:48   ` [PATCH v2 6/6] dynlink.c: store bloom filter size in struct dso Alexander Monakov
2015-06-28  2:45   ` [PATCH v2 0/6] gnu-hash speedups Rich Felker

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1435101895-18240-4-git-send-email-amonakov@ispras.ru \
    --to=amonakov@ispras.ru \
    --cc=musl@lists.openwall.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
Code repositories for project(s) associated with this public inbox

	https://git.vuxu.org/mirror/musl/

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).