From: Mike Frysinger Date: Wed, 12 Sep 2007 08:30:15 +0000 (+0800) Subject: Blackfin arch: fix some bugs in lib/string.h functions found by our string testing... X-Git-Tag: v2.6.23-rc7~44^2 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0931ce8439365358b1cacf888ddc8fb008036125;p=linux-2.6 Blackfin arch: fix some bugs in lib/string.h functions found by our string testing modules - use ints for the return value rather than char since we actually return an int and we dont want it improperly being sign extended during the reload http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=3525 - if src is shorter than the requested number of copy bytes, we need to null pad the rest http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=3524 - mark these as __volatile__ and add memory to the clobber list so gcc does not optimize buffers around on us we may be using - rewrite asm code to be readable/maintainable Signed-off-by: Mike Frysinger Signed-off-by: Bryan Wu --- diff --git a/include/asm-blackfin/string.h b/include/asm-blackfin/string.h index 6f1eb7d6d3..e8ada91ab0 100644 --- a/include/asm-blackfin/string.h +++ b/include/asm-blackfin/string.h @@ -9,13 +9,16 @@ extern inline char *strcpy(char *dest, const char *src) char *xdest = dest; char temp = 0; - __asm__ __volatile__ - ("1:\t%2 = B [%1++] (Z);\n\t" - "B [%0++] = %2;\n\t" - "CC = %2;\n\t" - "if cc jump 1b (bp);\n" - : "+&a" (dest), "+&a" (src), "=&d" (temp) - ::"memory", "CC"); + __asm__ __volatile__ ( + "1:" + "%2 = B [%1++] (Z);" + "B [%0++] = %2;" + "CC = %2;" + "if cc jump 1b (bp);" + : "+&a" (dest), "+&a" (src), "=&d" (temp) + : + : "memory", "CC"); + return xdest; } @@ -28,37 +31,56 @@ extern inline char *strncpy(char *dest, const char *src, size_t n) if (n == 0) return xdest; - __asm__ __volatile__ - ("1:\t%3 = B [%1++] (Z);\n\t" - "B [%0++] = %3;\n\t" - "CC = %3;\n\t" - "if ! cc jump 2f;\n\t" - "%2 += -1;\n\t" - "CC = %2 == 0;\n\t" - "if ! cc jump 1b (bp);\n" - "2:\n" - : "+&a" (dest), "+&a" (src), "+&da" (n), "=&d" (temp) - ::"memory", "CC"); + __asm__ __volatile__ ( + "1:" + "%3 = B [%1++] (Z);" + "B [%0++] = %3;" + "CC = %3;" + "if ! cc jump 2f;" + "%2 += -1;" + "CC = %2 == 0;" + "if ! cc jump 1b (bp);" + "jump 4f;" + "2:" + /* if src is shorter than n, we need to null pad bytes now */ + "%3 = 0;" + "3:" + "%2 += -1;" + "CC = %2 == 0;" + "if cc jump 4f;" + "B [%0++] = %3;" + "jump 3b;" + "4:" + : "+&a" (dest), "+&a" (src), "+&da" (n), "=&d" (temp) + : + : "memory", "CC"); + return xdest; } #define __HAVE_ARCH_STRCMP extern inline int strcmp(const char *cs, const char *ct) { - char __res1, __res2; - - __asm__ - ("1:\t%2 = B[%0++] (Z);\n\t" /* get *cs */ - "%3 = B[%1++] (Z);\n\t" /* get *ct */ - "CC = %2 == %3;\n\t" /* compare a byte */ - "if ! cc jump 2f;\n\t" /* not equal, break out */ - "CC = %2;\n\t" /* at end of cs? */ - "if cc jump 1b (bp);\n\t" /* no, keep going */ - "jump.s 3f;\n" /* strings are equal */ - "2:\t%2 = %2 - %3;\n" /* *cs - *ct */ - "3:\n" - : "+&a" (cs), "+&a" (ct), "=&d" (__res1), "=&d" (__res2) - : : "CC"); + /* need to use int's here so the char's in the assembly don't get + * sign extended incorrectly when we don't want them to be + */ + int __res1, __res2; + + __asm__ __volatile__ ( + "1:" + "%2 = B[%0++] (Z);" /* get *cs */ + "%3 = B[%1++] (Z);" /* get *ct */ + "CC = %2 == %3;" /* compare a byte */ + "if ! cc jump 2f;" /* not equal, break out */ + "CC = %2;" /* at end of cs? */ + "if cc jump 1b (bp);" /* no, keep going */ + "jump.s 3f;" /* strings are equal */ + "2:" + "%2 = %2 - %3;" /* *cs - *ct */ + "3:" + : "+&a" (cs), "+&a" (ct), "=&d" (__res1), "=&d" (__res2) + : + : "memory", "CC"); return __res1; } @@ -66,26 +88,35 @@ extern inline int strcmp(const char *cs, const char *ct) #define __HAVE_ARCH_STRNCMP extern inline int strncmp(const char *cs, const char *ct, size_t count) { - char __res1, __res2; + /* need to use int's here so the char's in the assembly don't get + * sign extended incorrectly when we don't want them to be + */ + int __res1, __res2; if (!count) return 0; - __asm__ - ("1:\t%3 = B[%0++] (Z);\n\t" /* get *cs */ - "%4 = B[%1++] (Z);\n\t" /* get *ct */ - "CC = %3 == %4;\n\t" /* compare a byte */ - "if ! cc jump 3f;\n\t" /* not equal, break out */ - "CC = %3;\n\t" /* at end of cs? */ - "if ! cc jump 4f;\n\t" /* yes, all done */ - "%2 += -1;\n\t" /* no, adjust count */ - "CC = %2 == 0;\n\t" - "if ! cc jump 1b;\n" /* more to do, keep going */ - "2:\t%3 = 0;\n\t" /* strings are equal */ - "jump.s 4f;\n" - "3:\t%3 = %3 - %4;\n" /* *cs - *ct */ - "4:" - : "+&a" (cs), "+&a" (ct), "+&da" (count), "=&d" (__res1), "=&d" (__res2) - : : "CC"); + + __asm__ __volatile__ ( + "1:" + "%3 = B[%0++] (Z);" /* get *cs */ + "%4 = B[%1++] (Z);" /* get *ct */ + "CC = %3 == %4;" /* compare a byte */ + "if ! cc jump 3f;" /* not equal, break out */ + "CC = %3;" /* at end of cs? */ + "if ! cc jump 4f;" /* yes, all done */ + "%2 += -1;" /* no, adjust count */ + "CC = %2 == 0;" + "if ! cc jump 1b;" /* more to do, keep going */ + "2:" + "%3 = 0;" /* strings are equal */ + "jump.s 4f;" + "3:" + "%3 = %3 - %4;" /* *cs - *ct */ + "4:" + : "+&a" (cs), "+&a" (ct), "+&da" (count), "=&d" (__res1), "=&d" (__res2) + : + : "memory", "CC"); + return __res1; }