musl/arch/mips/atomic.h
Rich Felker 036eaa24cf avoid need for -march=mips2 to compile mips atomic.h asm
linux guarantees ll/sc are always available. on mips1, they will be
emulated by the kernel. thus they are part of the linux mips1 abi and
safe to use.
2012-08-11 19:51:21 -04:00

200 lines
3.6 KiB
C

#ifndef _INTERNAL_ATOMIC_H
#define _INTERNAL_ATOMIC_H
#include <stdint.h>
static inline int a_ctz_l(unsigned long x)
{
static const char debruijn32[32] = {
0, 1, 23, 2, 29, 24, 19, 3, 30, 27, 25, 11, 20, 8, 4, 13,
31, 22, 28, 18, 26, 10, 7, 12, 21, 17, 9, 6, 16, 5, 15, 14
};
return debruijn32[(x&-x)*0x076be629 >> 27];
}
static inline int a_ctz_64(uint64_t x)
{
uint32_t y = x;
if (!y) {
y = x>>32;
return 32 + a_ctz_l(y);
}
return a_ctz_l(y);
}
static inline int a_cas(volatile int *p, int t, int s)
{
int dummy;
__asm__ __volatile__(
".set push\n"
".set mips2\n"
".set noreorder\n"
"1: ll %0, 0(%2)\n"
" bne %0, %3, 1f\n"
" addu %1, %4, $0\n"
" sc %1, 0(%2)\n"
" beq %1, $0, 1b\n"
" nop\n"
"1: \n"
".set pop\n"
: "=&r"(t), "=&r"(dummy) : "r"(p), "r"(t), "r"(s) : "memory" );
return t;
}
static inline void *a_cas_p(volatile void *p, void *t, void *s)
{
return (void *)a_cas(p, (int)t, (int)s);
}
static inline long a_cas_l(volatile void *p, long t, long s)
{
return a_cas(p, t, s);
}
static inline int a_swap(volatile int *x, int v)
{
int old, dummy;
__asm__ __volatile__(
".set push\n"
".set mips2\n"
".set noreorder\n"
"1: ll %0, 0(%2)\n"
" addu %1, %3, $0\n"
" sc %1, 0(%2)\n"
" beq %1, $0, 1b\n"
" nop\n"
"1: \n"
".set pop\n"
: "=&r"(old), "=&r"(dummy) : "r"(x), "r"(v) : "memory" );
return old;
}
static inline int a_fetch_add(volatile int *x, int v)
{
int old, dummy;
__asm__ __volatile__(
".set push\n"
".set mips2\n"
".set noreorder\n"
"1: ll %0, 0(%2)\n"
" addu %1, %0, %3\n"
" sc %1, 0(%2)\n"
" beq %1, $0, 1b\n"
" nop\n"
"1: \n"
".set pop\n"
: "=&r"(old), "=&r"(dummy) : "r"(x), "r"(v) : "memory" );
return old;
}
static inline void a_inc(volatile int *x)
{
int dummy;
__asm__ __volatile__(
".set push\n"
".set mips2\n"
".set noreorder\n"
"1: ll %0, 0(%1)\n"
" addu %0, %0, 1\n"
" sc %0, 0(%1)\n"
" beq %0, $0, 1b\n"
" nop\n"
"1: \n"
".set pop\n"
: "=&r"(dummy) : "r"(x) : "memory" );
}
static inline void a_dec(volatile int *x)
{
int dummy;
__asm__ __volatile__(
".set push\n"
".set mips2\n"
".set noreorder\n"
"1: ll %0, 0(%1)\n"
" subu %0, %0, 1\n"
" sc %0, 0(%1)\n"
" beq %0, $0, 1b\n"
" nop\n"
"1: \n"
".set pop\n"
: "=&r"(dummy) : "r"(x) : "memory" );
}
static inline void a_store(volatile int *p, int x)
{
int dummy;
__asm__ __volatile__(
".set push\n"
".set mips2\n"
".set noreorder\n"
"1: ll %0, 0(%1)\n"
" addu %0, %2, $0\n"
" sc %0, 0(%1)\n"
" beq %0, $0, 1b\n"
" nop\n"
"1: \n"
".set pop\n"
: "=&r"(dummy) : "r"(p), "r"(x) : "memory" );
}
static inline void a_spin()
{
}
static inline void a_crash()
{
*(volatile char *)0=0;
}
static inline void a_and(volatile int *p, int v)
{
int dummy;
__asm__ __volatile__(
".set push\n"
".set mips2\n"
".set noreorder\n"
"1: ll %0, 0(%1)\n"
" and %0, %0, %2\n"
" sc %0, 0(%1)\n"
" beq %0, $0, 1b\n"
" nop\n"
"1: \n"
".set pop\n"
: "=&r"(dummy) : "r"(p), "r"(v) : "memory" );
}
static inline void a_or(volatile int *p, int v)
{
int dummy;
__asm__ __volatile__(
".set push\n"
".set mips2\n"
".set noreorder\n"
"1: ll %0, 0(%1)\n"
" or %0, %0, %2\n"
" sc %0, 0(%1)\n"
" beq %0, $0, 1b\n"
" nop\n"
"1: \n"
".set pop\n"
: "=&r"(dummy) : "r"(p), "r"(v) : "memory" );
}
static inline void a_and_64(volatile uint64_t *p, uint64_t v)
{
union { uint64_t v; uint32_t r[2]; } u = { v };
a_and((int *)p, u.r[0]);
a_and((int *)p+1, u.r[1]);
}
static inline void a_or_64(volatile uint64_t *p, uint64_t v)
{
union { uint64_t v; uint32_t r[2]; } u = { v };
a_or((int *)p, u.r[0]);
a_or((int *)p+1, u.r[1]);
}
#endif