diff options
Diffstat (limited to 'wasm')
-rw-r--r-- | wasm/asyncify.h | 10 | ||||
-rw-r--r-- | wasm/setjmp.c | 70 | ||||
-rw-r--r-- | wasm/setjmp.h | 34 |
3 files changed, 114 insertions, 0 deletions
diff --git a/wasm/asyncify.h b/wasm/asyncify.h index 834fc8b570..49eb125593 100644 --- a/wasm/asyncify.h +++ b/wasm/asyncify.h @@ -3,8 +3,18 @@ __attribute__((import_module("asyncify"), import_name("start_unwind"))) void asyncify_start_unwind(void *buf); +#define asyncify_start_unwind(buf) do { \ + extern void *rb_asyncify_unwind_buf; \ + rb_asyncify_unwind_buf = (buf); \ + asyncify_start_unwind((buf)); \ + } while (0) __attribute__((import_module("asyncify"), import_name("stop_unwind"))) void asyncify_stop_unwind(void); +#define asyncify_stop_unwind() do { \ + extern void *rb_asyncify_unwind_buf; \ + rb_asyncify_unwind_buf = NULL; \ + asyncify_stop_unwind(); \ + } while (0) __attribute__((import_module("asyncify"), import_name("start_rewind"))) void asyncify_start_rewind(void *buf); __attribute__((import_module("asyncify"), import_name("stop_rewind"))) diff --git a/wasm/setjmp.c b/wasm/setjmp.c index 3f017e202a..1e69cb1c64 100644 --- a/wasm/setjmp.c +++ b/wasm/setjmp.c @@ -57,6 +57,7 @@ async_buf_init(struct __rb_wasm_asyncify_jmp_buf* buf) // Global unwinding/rewinding jmpbuf state static rb_wasm_jmp_buf *_rb_wasm_active_jmpbuf; +void *rb_asyncify_unwind_buf; __attribute__((noinline)) int @@ -106,6 +107,75 @@ _rb_wasm_longjmp(rb_wasm_jmp_buf* env, int value) asyncify_start_unwind(&env->longjmp_buf); } + +enum try_catch_phase { + TRY_CATCH_PHASE_MAIN = 0, + TRY_CATCH_PHASE_RESCUE = 1, +}; + +void +rb_wasm_try_catch_init(struct rb_wasm_try_catch *try_catch, + rb_wasm_try_catch_func_t try_f, + rb_wasm_try_catch_func_t catch_f, + void *context) +{ + try_catch->state = TRY_CATCH_PHASE_MAIN; + try_catch->try_f = try_f; + try_catch->catch_f = catch_f; + try_catch->context = context; +} + +// NOTE: This function is not processed by Asyncify due to a call of asyncify_stop_rewind +void +rb_wasm_try_catch_loop_run(struct rb_wasm_try_catch *try_catch, rb_wasm_jmp_buf *target) +{ + extern void *rb_asyncify_unwind_buf; + extern rb_wasm_jmp_buf *_rb_wasm_active_jmpbuf; + + target->state = JMP_BUF_STATE_CAPTURED; + + switch ((enum try_catch_phase)try_catch->state) { + case TRY_CATCH_PHASE_MAIN: { + // may unwind + try_catch->try_f(try_catch->context); + break; + } + case TRY_CATCH_PHASE_RESCUE: { + if (try_catch->catch_f) { + // may unwind + try_catch->catch_f(try_catch->context); + } + break; + } + } + + while (1) { + // catch longjmp with target jmp_buf + if (rb_asyncify_unwind_buf && _rb_wasm_active_jmpbuf == target) { + // do similar steps setjmp does when JMP_BUF_STATE_RETURNING + + // stop unwinding + // (but call stop_rewind to update the asyncify state to "normal" from "unwind") + asyncify_stop_rewind(); + // clear the active jmpbuf because it's already stopped + _rb_wasm_active_jmpbuf = NULL; + // reset jmpbuf state to be able to unwind again + target->state = JMP_BUF_STATE_CAPTURED; + // move to catch loop phase + try_catch->state = TRY_CATCH_PHASE_RESCUE; + if (try_catch->catch_f) { + try_catch->catch_f(try_catch->context); + } + continue; + } else if (rb_asyncify_unwind_buf /* unrelated unwind */) { + return; + } + // no unwind, then exit + break; + } + return; +} + void * rb_wasm_handle_jmp_unwind(void) { diff --git a/wasm/setjmp.h b/wasm/setjmp.h index 30ea23ca12..65e35c03b3 100644 --- a/wasm/setjmp.h +++ b/wasm/setjmp.h @@ -58,4 +58,38 @@ typedef rb_wasm_jmp_buf jmp_buf; #define setjmp(env) rb_wasm_setjmp(env) #define longjmp(env, payload) rb_wasm_longjmp(env, payload) + +typedef void (*rb_wasm_try_catch_func_t)(void *ctx); + +struct rb_wasm_try_catch { + rb_wasm_try_catch_func_t try_f; + rb_wasm_try_catch_func_t catch_f; + void *context; + int state; +}; + +// +// Lightweight try-catch API without unwinding to root frame. +// + +void +rb_wasm_try_catch_init(struct rb_wasm_try_catch *try_catch, + rb_wasm_try_catch_func_t try_f, + rb_wasm_try_catch_func_t catch_f, + void *context); + +// Run, catch longjmp thrown by run, and re-catch longjmp thrown by catch, ... +// +// 1. run try_f of try_catch struct +// 2. catch longjmps with the given target jmp_buf or exit +// 3. run catch_f if not NULL, otherwise exit +// 4. catch longjmps with the given target jmp_buf or exit +// 5. repeat from step 3 +// +// NOTICE: This API assumes that all longjmp targeting the given jmp_buf are NOT called +// after the function that called this function has exited. +// +void +rb_wasm_try_catch_loop_run(struct rb_wasm_try_catch *try_catch, rb_wasm_jmp_buf *target); + #endif |