Ruby 2.7.0p0(2019-12-25revision647ee6f091eafcce70ffb75ddf7e121e192ab217)

Context.h
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1 #pragma once
2
3 #include <assert.h>
4 #include <string.h>
5
6 #define COROUTINE __attribute__((noreturn)) void
7
8 enum {
9 COROUTINE_REGISTERS =
10 19 /* 18 general purpose registers (r14-r31) and 1 return address */
11 + 4 /* space for fiber_entry() to store the link register */
12 };
13
14 struct coroutine_context
15 {
16 void **stack_pointer;
17 };
18
19 typedef COROUTINE(* coroutine_start)(struct coroutine_context *from, struct coroutine_context *self);
20
21 static inline void coroutine_initialize_main(struct coroutine_context * context) {
22 context->stack_pointer = NULL;
23 }
24
25 static inline void coroutine_initialize(
26 struct coroutine_context *context,
27 coroutine_start start,
28 void *stack,
29 size_t size
30 ) {
31 assert(start && stack && size >= 1024);
32
33 // Stack grows down. Force 16-byte alignment.
34 char * top = (char*)stack + size;
35 context->stack_pointer = (void**)((uintptr_t)top & ~0xF);
36
37 context->stack_pointer -= COROUTINE_REGISTERS;
38 memset(context->stack_pointer, 0, sizeof(void*) * COROUTINE_REGISTERS);
39
40 /* Skip a global prologue that sets the TOC register */
41 context->stack_pointer[18] = ((char*)start) + 8;
42 }
43
44 struct coroutine_context * coroutine_transfer(struct coroutine_context * current, struct coroutine_context * target);
45
46 static inline void coroutine_destroy(struct coroutine_context * context)
47 {
48 context->stack_pointer = NULL;
49 }
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:6
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