Ruby  2.7.0p0(2019-12-25revision647ee6f091eafcce70ffb75ddf7e121e192ab217)
Context.h
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1 /*
2  * This file is part of the "Coroutine" project and released under the MIT License.
3  *
4  * Created by Samuel Williams on 10/5/2018.
5  * Copyright, 2018, by Samuel Williams. All rights reserved.
6 */
7 
8 #pragma once
9 
10 #include <assert.h>
11 #include <string.h>
12 
13 #define COROUTINE __attribute__((noreturn)) void
14 
16 
18 {
19  void **stack_pointer;
20 };
21 
23 
24 static inline void coroutine_initialize_main(struct coroutine_context * context) {
25  context->stack_pointer = NULL;
26 }
27 
28 static inline void coroutine_initialize(
29  struct coroutine_context *context,
30  coroutine_start start,
31  void *stack,
32  size_t size
33 ) {
34  assert(start && stack && size >= 1024);
35 
36  // Stack grows down. Force 16-byte alignment.
37  char * top = (char*)stack + size;
38  context->stack_pointer = (void**)((uintptr_t)top & ~0xF);
39 
40  *--context->stack_pointer = NULL;
41  *--context->stack_pointer = (void*)start;
42 
44  memset(context->stack_pointer, 0, sizeof(void*) * COROUTINE_REGISTERS);
45 }
46 
47 struct coroutine_context * coroutine_transfer(struct coroutine_context * current, struct coroutine_context * target);
48 
49 static inline void coroutine_destroy(struct coroutine_context * context)
50 {
51  context->stack_pointer = NULL;
52 }
coroutine_context::stack
void * stack
Definition: Context.h:29
assert
#define assert(x)
Definition: dlmalloc.c:1176
memset
void * memset(void *, int, size_t)
COROUTINE_REGISTERS
@ COROUTINE_REGISTERS
Definition: Context.h:15
assert.h
uintptr_t
unsigned int uintptr_t
Definition: win32.h:106
NULL
#define NULL
Definition: _sdbm.c:101
COROUTINE
#define COROUTINE
Definition: Context.h:13
coroutine_start
COROUTINE(* coroutine_start)(struct coroutine_context *from, struct coroutine_context *self)
Definition: Context.h:22
coroutine_context::from
struct coroutine_context * from
Definition: Context.h:37
size
int size
Definition: encoding.c:58
coroutine_context
Definition: Context.h:17
coroutine_transfer
struct coroutine_context * coroutine_transfer(struct coroutine_context *current, struct coroutine_context *target)
Definition: Context.c:115
top
unsigned int top
Definition: nkf.c:4323
coroutine_context::stack_pointer
void ** stack_pointer
Definition: Context.h:19