bsnes/libco/aarch64.c

107 lines
3.0 KiB
C

#define LIBCO_C
#include "libco.h"
#include "settings.h"
#include <stdint.h>
#ifdef LIBCO_MPROTECT
#include <unistd.h>
#include <sys/mman.h>
#endif
#ifdef __cplusplus
extern "C" {
#endif
static thread_local unsigned long co_active_buffer[64];
static thread_local cothread_t co_active_handle = 0;
static void (*co_swap)(cothread_t, cothread_t) = 0;
#ifdef LIBCO_MPROTECT
alignas(4096)
#else
section(text)
#endif
static const uint32_t co_swap_function[1024] = {
0x910003f0, /* mov x16,sp */
0xa9007830, /* stp x16,x30,[x1] */
0xa9407810, /* ldp x16,x30,[x0] */
0x9100021f, /* mov sp,x16 */
0xa9015033, /* stp x19,x20,[x1, 16] */
0xa9415013, /* ldp x19,x20,[x0, 16] */
0xa9025835, /* stp x21,x22,[x1, 32] */
0xa9425815, /* ldp x21,x22,[x0, 32] */
0xa9036037, /* stp x23,x24,[x1, 48] */
0xa9436017, /* ldp x23,x24,[x0, 48] */
0xa9046839, /* stp x25,x26,[x1, 64] */
0xa9446819, /* ldp x25,x26,[x0, 64] */
0xa905703b, /* stp x27,x28,[x1, 80] */
0xa945701b, /* ldp x27,x28,[x0, 80] */
0xf900303d, /* str x29, [x1, 96] */
0xf940301d, /* ldr x29, [x0, 96] */
0x6d072428, /* stp d8, d9, [x1,112] */
0x6d472408, /* ldp d8, d9, [x0,112] */
0x6d082c2a, /* stp d10,d11,[x1,128] */
0x6d482c0a, /* ldp d10,d11,[x0,128] */
0x6d09342c, /* stp d12,d13,[x1,144] */
0x6d49340c, /* ldp d12,d13,[x0,144] */
0x6d0a3c2e, /* stp d14,d15,[x1,160] */
0x6d4a3c0e, /* ldp d14,d15,[x0,160] */
0xd61f03c0, /* br x30 */
};
static void co_init() {
#ifdef LIBCO_MPROTECT
unsigned long addr = (unsigned long)co_swap_function;
unsigned long base = addr - (addr % sysconf(_SC_PAGESIZE));
unsigned long size = (addr - base) + sizeof co_swap_function;
mprotect((void*)base, size, PROT_READ | PROT_EXEC);
#endif
}
cothread_t co_active() {
if(!co_active_handle) co_active_handle = &co_active_buffer;
return co_active_handle;
}
cothread_t co_derive(void* memory, unsigned int size, void (*entrypoint)(void)) {
unsigned long* handle;
if(!co_swap) {
co_init();
co_swap = (void (*)(cothread_t, cothread_t))co_swap_function;
}
if(!co_active_handle) co_active_handle = &co_active_buffer;
if(handle = (unsigned long*)memory) {
unsigned int offset = (size & ~15);
unsigned long* p = (unsigned long*)((unsigned char*)handle + offset);
handle[0] = (unsigned long)p; /* x16 (stack pointer) */
handle[1] = (unsigned long)entrypoint; /* x30 (link register) */
handle[12] = (unsigned long)p; /* x29 (frame pointer) */
}
return handle;
}
cothread_t co_create(unsigned int size, void (*entrypoint)(void)) {
void* memory = LIBCO_MALLOC(size);
if(!memory) return (cothread_t)0;
return co_derive(memory, size, entrypoint);
}
void co_delete(cothread_t handle) {
LIBCO_FREE(handle);
}
void co_switch(cothread_t handle) {
cothread_t co_previous_handle = co_active_handle;
co_swap(co_active_handle = handle, co_previous_handle);
}
int co_serializable() {
return 1;
}
#ifdef __cplusplus
}
#endif