From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755596AbbKWVdZ (ORCPT ); Mon, 23 Nov 2015 16:33:25 -0500 Received: from mail-lf0-f44.google.com ([209.85.215.44]:35400 "EHLO mail-lf0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752181AbbKWV3w (ORCPT ); Mon, 23 Nov 2015 16:29:52 -0500 From: Rasmus Villemoes To: Andrew Morton Cc: Rasmus Villemoes , linux-kernel@vger.kernel.org Subject: [PATCH 05/14] lib/vsprintf.c: help gcc make number() smaller Date: Mon, 23 Nov 2015 22:29:22 +0100 Message-Id: <1448314171-25856-6-git-send-email-linux@rasmusvillemoes.dk> X-Mailer: git-send-email 2.6.1 In-Reply-To: <1448314171-25856-1-git-send-email-linux@rasmusvillemoes.dk> References: <1448314171-25856-1-git-send-email-linux@rasmusvillemoes.dk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org One consequence of the reorganization of struct printf_spec to make field_width 24 bits was that number() gained about 180 bytes. Since spec is never passed to other functions, we can help gcc make number() lose most of that extra weight by using local variables for the field width and precision. Signed-off-by: Rasmus Villemoes --- lib/vsprintf.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 01c3aa638582..d7e27c54fa00 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -399,6 +399,8 @@ char *number(char *buf, char *end, unsigned long long num, int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); int i; bool is_zero = num == 0LL; + int field_width = spec.field_width; + int precision = spec.precision; /* locase = 0 or 0x20. ORing digits or letters with 'locase' * produces same digits or (maybe lowercased) letters */ @@ -410,20 +412,20 @@ char *number(char *buf, char *end, unsigned long long num, if ((signed long long)num < 0) { sign = '-'; num = -(signed long long)num; - spec.field_width--; + field_width--; } else if (spec.flags & PLUS) { sign = '+'; - spec.field_width--; + field_width--; } else if (spec.flags & SPACE) { sign = ' '; - spec.field_width--; + field_width--; } } if (need_pfx) { if (spec.base == 16) - spec.field_width -= 2; + field_width -= 2; else if (!is_zero) - spec.field_width--; + field_width--; } /* generate full string in tmp[], in reverse order */ @@ -445,12 +447,12 @@ char *number(char *buf, char *end, unsigned long long num, } /* printing 100 using %2d gives "100", not "00" */ - if (i > spec.precision) - spec.precision = i; + if (i > precision) + precision = i; /* leading space padding */ - spec.field_width -= spec.precision; + field_width -= precision; if (!(spec.flags & (ZEROPAD | LEFT))) { - while (--spec.field_width >= 0) { + while (--field_width >= 0) { if (buf < end) *buf = ' '; ++buf; @@ -479,14 +481,14 @@ char *number(char *buf, char *end, unsigned long long num, if (!(spec.flags & LEFT)) { char c = ' ' + (spec.flags & ZEROPAD); BUILD_BUG_ON(' ' + ZEROPAD != '0'); - while (--spec.field_width >= 0) { + while (--field_width >= 0) { if (buf < end) *buf = c; ++buf; } } /* hmm even more zero padding? */ - while (i <= --spec.precision) { + while (i <= --precision) { if (buf < end) *buf = '0'; ++buf; @@ -498,7 +500,7 @@ char *number(char *buf, char *end, unsigned long long num, ++buf; } /* trailing space padding */ - while (--spec.field_width >= 0) { + while (--field_width >= 0) { if (buf < end) *buf = ' '; ++buf; -- 2.6.1