+ lib-vsprintfc-help-gcc-make-number-smaller.patch added to -mm tree

* + lib-vsprintfc-help-gcc-make-number-smaller.patch added to -mm tree
@ 2015-12-03 23:35 akpm
  0 siblings, 0 replies; 2+ messages in thread
From: akpm @ 2015-12-03 23:35 UTC (permalink / raw)
  To: linux, andy.shevchenko, joe, keescook, mingo, mlombard, tj, viro,
	mm-commits


The patch titled
     Subject: lib/vsprintf.c: help gcc make number() smaller
has been added to the -mm tree.  Its filename is
     lib-vsprintfc-help-gcc-make-number-smaller.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/lib-vsprintfc-help-gcc-make-number-smaller.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/lib-vsprintfc-help-gcc-make-number-smaller.patch

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------------------------------------------------------
From: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Subject: lib/vsprintf.c: help gcc make number() smaller

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.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/vsprintf.c |   26 ++++++++++++++------------
 1 file changed, 14 insertions(+), 12 deletions(-)

diff -puN lib/vsprintf.c~lib-vsprintfc-help-gcc-make-number-smaller lib/vsprintf.c

--- a/lib/vsprintf.c~lib-vsprintfc-help-gcc-make-number-smaller
+++ a/lib/vsprintf.c
@@ -398,6 +398,8 @@ char *number(char *buf, char *end, unsig
 	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;
 
 	BUILD_BUG_ON(sizeof(struct printf_spec) != 8);
 
@@ -411,20 +413,20 @@ char *number(char *buf, char *end, unsig
 		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 */
@@ -446,12 +448,12 @@ char *number(char *buf, char *end, unsig
 	}
 
 	/* 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;
@@ -480,14 +482,14 @@ char *number(char *buf, char *end, unsig
 	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;
@@ -499,7 +501,7 @@ char *number(char *buf, char *end, unsig
 		++buf;
 	}
 	/* trailing space padding */
-	while (--spec.field_width >= 0) {
+	while (--field_width >= 0) {
 		if (buf < end)
 			*buf = ' ';
 		++buf;
_

Patches currently in -mm which might be from linux@rasmusvillemoes.dk are

lib-vsprintfc-pull-out-padding-code-from-dentry_name.patch
lib-vsprintfc-move-string-below-widen_string.patch
lib-vsprintfc-eliminate-potential-race-in-string.patch
lib-vsprintfc-expand-field_width-to-24-bits.patch
lib-vsprintfc-help-gcc-make-number-smaller.patch
lib-vsprintfc-warn-about-too-large-precisions-and-field-widths.patch
lib-kasprintfc-add-sanity-check-to-kvasprintf.patch
lib-test_printfc-dont-bug.patch
lib-test_printfc-check-for-out-of-bound-writes.patch
lib-test_printfc-test-precision-quirks.patch
lib-test_printfc-add-a-few-number-tests.patch
lib-test_printfc-account-for-kvasprintf-tests.patch
lib-test_printfc-add-test-for-large-bitmaps.patch
lib-test_printfc-test-dentry-printing.patch
powerpc-fadump-rename-cpu_online_mask-member-of-struct-fadump_crash_info_header.patch
kernel-cpuc-change-type-of-cpu_possible_bits-and-friends.patch
kernel-cpuc-export-__cpu__mask.patch
drivers-base-cpuc-use-__cpu__mask-directly.patch
kernel-cpuc-eliminate-cpu__mask.patch
kernel-cpuc-make-set_cpu_-static-inlines.patch


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