48 lines
1.6 KiB
C++
48 lines
1.6 KiB
C++
#ifndef COSMOPOLITAN_LIBC_RUNTIME_GC_H_
|
|
#define COSMOPOLITAN_LIBC_RUNTIME_GC_H_
|
|
#include "libc/calls/calls.h"
|
|
#include "libc/nexgen32e/stackframe.h"
|
|
#include "libc/runtime/runtime.h"
|
|
#if !(__ASSEMBLER__ + __LINKER__ + 0)
|
|
COSMOPOLITAN_C_START_
|
|
|
|
/**
|
|
* @fileoverview Cosmopolitan Return-Oriented Garbage Collector.
|
|
*
|
|
* This is the same thing as {@code std::unique_ptr<>} in C++ or the
|
|
* {@code defer} keyword in Go. We harness the power of ROP for good
|
|
* using very few lines of code.
|
|
*/
|
|
|
|
/**
|
|
* Releases resource when function returns.
|
|
*
|
|
* @warning do not return a gc()'d pointer
|
|
* @warning do not realloc() with gc()'d pointer
|
|
*/
|
|
#define gc(THING) defer((void *)weakfree, (void *)(THING))
|
|
|
|
/**
|
|
* Same as longjmp() but runs gc() / defer() destructors.
|
|
*/
|
|
void gclongjmp(jmp_buf, int) nothrow wontreturn paramsnonnull();
|
|
|
|
/**
|
|
* Calls FN(ARG) when function returns.
|
|
*/
|
|
#define defer(FN, ARG) \
|
|
({ \
|
|
autotype(ARG) Arg = (ARG); \
|
|
/* prevent weird opts like tail call */ \
|
|
asm volatile("" : "+g"(Arg) : : "memory"); \
|
|
__defer((struct StackFrame *)__builtin_frame_address(0), FN, Arg); \
|
|
asm volatile("" : "+g"(Arg) : : "memory"); \
|
|
Arg; \
|
|
})
|
|
|
|
void __defer(struct StackFrame *, void *, void *) hidden paramsnonnull((1, 2));
|
|
|
|
COSMOPOLITAN_C_END_
|
|
#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
|
|
#endif /* COSMOPOLITAN_LIBC_RUNTIME_GC_H_ */
|