Mercurial > hg > nginx-vendor-0-6
diff src/os/unix/ngx_gcc_atomic_ppc.h @ 110:dad2fe8ecf08 NGINX_0_3_2
nginx 0.3.2
*) Feature: the Sun Studio 10 C compiler support.
*) Feature: the "proxy_upstream_max_fails",
"proxy_upstream_fail_timeout", "fastcgi_upstream_max_fails", and
"fastcgi_upstream_fail_timeout" directives.
author | Igor Sysoev <http://sysoev.ru> |
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date | Wed, 12 Oct 2005 00:00:00 +0400 |
parents | |
children | 408f195b3482 |
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new file mode 100644 --- /dev/null +++ b/src/os/unix/ngx_gcc_atomic_ppc.h @@ -0,0 +1,66 @@ + +/* + * Copyright (C) Igor Sysoev + */ + + +/* + * The ppc assembler treats ";" as comment, so we have to use "\n". + * The minus in "bne-" is a hint for the branch prediction unit that + * this branch is unlikely to be taken. + * The "1b" means the nearest backward label "1" and the "1f" means + * the nearest forward label "1". + * + * The "b" means that the base registers can be used only, i.e. + * any register except r0. The r0 register always has a zero value and + * could not be used in "addi r0, r0, 1". + * The "=&b" means that no input registers can be used. + */ + +static ngx_inline ngx_atomic_uint_t +ngx_atomic_cmp_set(ngx_atomic_t *lock, ngx_atomic_uint_t old, + ngx_atomic_uint_t set) +{ + ngx_atomic_uint_t res, temp; + + __asm__ volatile ( + + " li %0, 0 \n" /* preset "0" to "res" */ + " lwarx %1, 0, %2 \n" /* load from [lock] into "temp" */ + /* and store reservation */ + " cmpw %1, %3 \n" /* compare "temp" and "old" */ + " bne- 1f \n" /* not equal */ + " stwcx. %4, 0, %2 \n" /* store "set" into [lock] if reservation */ + /* is not cleared */ + " bne- 1f \n" /* the reservation was cleared */ + " li %0, 1 \n" /* set "1" to "res" */ + "1: \n" + + : "=&b" (res), "=&b" (temp) + : "b" (lock), "b" (old), "b" (set) + : "cc", "memory"); + + return res; +} + + +static ngx_inline ngx_atomic_int_t +ngx_atomic_fetch_add(ngx_atomic_t *value, ngx_atomic_int_t add) +{ + ngx_atomic_uint_t res, temp; + + __asm__ volatile ( + + "1: lwarx %0, 0, %2 \n" /* load from [value] into "res" */ + /* and store reservation */ + " add %1, %0, %3 \n" /* "res" + "add" store in "temp" */ + " stwcx. %1, 0, %2 \n" /* store "temp" into [value] if reservation */ + /* is not cleared */ + " bne- 1b \n" /* try again if reservation was cleared */ + + : "=&b" (res), "=&b" (temp) + : "b" (value), "b" (add) + : "cc", "memory"); + + return res; +}