summaryrefslogtreecommitdiff
path: root/libco/amd64.c
blob: 5d74bf65386b7680f39f159cac1be1d2d31c2a91 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
/*
  libco.amd64 (2009-10-12)
  author: byuu
  license: public domain
*/

#define LIBCO_C
#include <libco.h>
#include <assert.h>
#include <stdlib.h>

#ifdef __cplusplus
extern "C" {
#endif

static thread_local long long co_active_buffer[64];
static thread_local cothread_t co_active_handle = 0;
static void (*co_swap)(cothread_t, cothread_t) = 0;

#ifdef _WIN32
//ABI: Win64
static unsigned char co_swap_function[] = {
  0x48, 0x89, 0x22,                                 /* mov    [rdx],rsp        */
  0x48, 0x8b, 0x21,                                 /* mov    rsp,[rcx]        */
  0x58,                                             /* pop    rax              */
  0x48, 0x89, 0x6a, 0x08,                           /* mov    [rdx+0x8],rbp    */
  0x48, 0x89, 0x72, 0x10,                           /* mov    [rdx+0x10],rsi   */
  0x48, 0x89, 0x7a, 0x18,                           /* mov    [rdx+0x18],rdi   */
  0x48, 0x89, 0x5a, 0x20,                           /* mov    [rdx+0x20],rbx   */
  0x4c, 0x89, 0x62, 0x28,                           /* mov    [rdx+0x28],r12   */
  0x4c, 0x89, 0x6a, 0x30,                           /* mov    [rdx+0x30],r13   */
  0x4c, 0x89, 0x72, 0x38,                           /* mov    [rdx+0x38],r14   */
  0x4c, 0x89, 0x7a, 0x40,                           /* mov    [rdx+0x40],r15   */
  0x48, 0x81, 0xc2, 0x80, 0x00, 0x00, 0x00,         /* add    rdx,0x80         */
  0x48, 0x83, 0xe2, 0xf0,                           /* and    rdx,-0x10        */
  0x0f, 0x29, 0x32,                                 /* movaps [rdx],xmm6       */
  0x0f, 0x29, 0x7a, 0x10,                           /* movaps [rdx+0x10],xmm7  */
  0x44, 0x0f, 0x29, 0x42, 0x20,                     /* movaps [rdx+0x20],xmm8  */
  0x44, 0x0f, 0x29, 0x4a, 0x30,                     /* movaps [rdx+0x30],xmm9  */
  0x44, 0x0f, 0x29, 0x52, 0x40,                     /* movaps [rdx+0x40],xmm10 */
  0x44, 0x0f, 0x29, 0x5a, 0x50,                     /* movaps [rdx+0x50],xmm11 */
  0x44, 0x0f, 0x29, 0x62, 0x60,                     /* movaps [rdx+0x60],xmm12 */
  0x44, 0x0f, 0x29, 0x6a, 0x70,                     /* movaps [rdx+0x70],xmm13 */
  0x44, 0x0f, 0x29, 0xb2, 0x80, 0x00, 0x00, 0x00,   /* movaps [rdx+0x80],xmm14 */
  0x44, 0x0f, 0x29, 0xba, 0x90, 0x00, 0x00, 0x00,   /* movaps [rdx+0x90],xmm15 */
  0x48, 0x8b, 0x69, 0x08,                           /* mov    rbp,[rcx+0x8]    */
  0x48, 0x8b, 0x71, 0x10,                           /* mov    rsi,[rcx+0x10]   */
  0x48, 0x8b, 0x79, 0x18,                           /* mov    rdi,[rcx+0x18]   */
  0x48, 0x8b, 0x59, 0x20,                           /* mov    rbx,[rcx+0x20]   */
  0x4c, 0x8b, 0x61, 0x28,                           /* mov    r12,[rcx+0x28]   */
  0x4c, 0x8b, 0x69, 0x30,                           /* mov    r13,[rcx+0x30]   */
  0x4c, 0x8b, 0x71, 0x38,                           /* mov    r14,[rcx+0x38]   */
  0x4c, 0x8b, 0x79, 0x40,                           /* mov    r15,[rcx+0x40]   */
  0x48, 0x81, 0xc1, 0x80, 0x00, 0x00, 0x00,         /* add    rcx,0x80         */
  0x48, 0x83, 0xe1, 0xf0,                           /* and    rcx,-0x10        */
  0x0f, 0x29, 0x31,                                 /* movaps [rcx],xmm6       */
  0x0f, 0x29, 0x79, 0x10,                           /* movaps [rcx+0x10],xmm7  */
  0x44, 0x0f, 0x29, 0x41, 0x20,                     /* movaps [rcx+0x20],xmm8  */
  0x44, 0x0f, 0x29, 0x49, 0x30,                     /* movaps [rcx+0x30],xmm9  */
  0x44, 0x0f, 0x29, 0x51, 0x40,                     /* movaps [rcx+0x40],xmm10 */
  0x44, 0x0f, 0x29, 0x59, 0x50,                     /* movaps [rcx+0x50],xmm11 */
  0x44, 0x0f, 0x29, 0x61, 0x60,                     /* movaps [rcx+0x60],xmm12 */
  0x44, 0x0f, 0x29, 0x69, 0x70,                     /* movaps [rcx+0x70],xmm13 */
  0x44, 0x0f, 0x29, 0xb1, 0x80, 0x00, 0x00, 0x00,   /* movaps [rcx+0x80],xmm14 */
  0x44, 0x0f, 0x29, 0xb9, 0x90, 0x00, 0x00, 0x00,   /* movaps [rcx+0x90],xmm15 */
  0xff, 0xe0,                                       /* jmp    rax              */
};

#include <windows.h>

void co_init(void)
{
   DWORD old_privileges;
   VirtualProtect(co_swap_function,
         sizeof(co_swap_function), PAGE_EXECUTE_READWRITE, &old_privileges);
}
#else
//ABI: SystemV
static unsigned char co_swap_function[] = {
  0x48, 0x89, 0x26,                                 /* mov    [rsi],rsp      */
  0x48, 0x8b, 0x27,                                 /* mov    rsp,[rdi]      */
  0x58,                                             /* pop    rax            */
  0x48, 0x89, 0x6e, 0x08,                           /* mov    [rsi+0x08],rbp */
  0x48, 0x89, 0x5e, 0x10,                           /* mov    [rsi+0x10],rbx */
  0x4c, 0x89, 0x66, 0x18,                           /* mov    [rsi+0x18],r12 */
  0x4c, 0x89, 0x6e, 0x20,                           /* mov    [rsi+0x20],r13 */
  0x4c, 0x89, 0x76, 0x28,                           /* mov    [rsi+0x28],r14 */
  0x4c, 0x89, 0x7e, 0x30,                           /* mov    [rsi+0x30],r15 */
  0x48, 0x8b, 0x6f, 0x08,                           /* mov    rbp,[rdi+0x08] */
  0x48, 0x8b, 0x5f, 0x10,                           /* mov    rbx,[rdi+0x10] */
  0x4c, 0x8b, 0x67, 0x18,                           /* mov    r12,[rdi+0x18] */
  0x4c, 0x8b, 0x6f, 0x20,                           /* mov    r13,[rdi+0x20] */
  0x4c, 0x8b, 0x77, 0x28,                           /* mov    r14,[rdi+0x28] */
  0x4c, 0x8b, 0x7f, 0x30,                           /* mov    r15,[rdi+0x30] */
  0xff, 0xe0,                                       /* jmp    rax            */
};

#include <unistd.h>
#include <sys/mman.h>

void co_init(void)
{
   unsigned long long addr = (unsigned long long)co_swap_function;
   unsigned long long base = addr - (addr % sysconf(_SC_PAGESIZE));
   unsigned long long size = (addr - base) + sizeof(co_swap_function);
   mprotect((void*)base, size, PROT_READ | PROT_WRITE | PROT_EXEC);
}
#endif

static void crash(void)
{
  assert(0); /* called only if cothread_t entrypoint returns */
}

cothread_t co_active(void)
{
  if (!co_active_handle)
     co_active_handle = &co_active_buffer;
  return co_active_handle;
}

cothread_t co_create(unsigned int size, void (*entrypoint)(void))
{
   cothread_t 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;
   size += 512; /* allocate additional space for storage */
   size &= ~15; /* align stack to 16-byte boundary */

   if(handle = (cothread_t)malloc(size))
   {
      long long *p = (long long*)((char*)handle + size); /* seek to top of stack */
      *--p = (long long)crash;                           /* crash if entrypoint returns */
      *--p = (long long)entrypoint;                      /* start of function */
      *(long long*)handle = (long long)p;                /* stack pointer */
   }

   return handle;
}

void co_delete(cothread_t handle)
{
   free(handle);
}

void co_switch(cothread_t handle)
{
  register cothread_t co_previous_handle = co_active_handle;
  co_swap(co_active_handle = handle, co_previous_handle);
}

#ifdef __cplusplus
}
#endif