From a58ed62a1677ab31de8ca63ba9cdb4694ae608fe Mon Sep 17 00:00:00 2001
From: theMackabu <theMackabu@gmail.com>
Date: Fri, 17 Apr 2026 12:19:12 -0700
Subject: [PATCH] migrate coro to a linked list

---
 include/sugar.h         |  2 ++
 src/modules/generator.c |  6 ++++++
 src/silver/ops/async.h  | 12 +++++++++---
 src/sugar.c             | 16 ++++++++++++++--
 4 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/include/sugar.h b/include/sugar.h
index 52e66ff..e969dcc 100644
--- a/include/sugar.h
+++ b/include/sugar.h
@@ -59,6 +59,8 @@ typedef struct coroutine {
   ant_value_t async_promise;
   
   struct coroutine *active_parent;
+  struct coroutine *active_prev;
+  
   struct coroutine *prev;
   struct coroutine *next;
   
diff --git a/src/modules/generator.c b/src/modules/generator.c
index ba3a467..a20574c 100644
--- a/src/modules/generator.c
+++ b/src/modules/generator.c
@@ -361,6 +361,9 @@ static ant_value_t generator_resume_kind(
   coroutine_t *saved_active = js->active_async_coro;
   
   coro->active_parent = saved_active;
+  coro->active_prev = NULL;
+  
+  if (saved_active) saved_active->active_prev = coro;
   js->active_async_coro = coro;
   coroutine_hold(coro, CORO_HOLD_ACTIVE);
 
@@ -382,7 +385,10 @@ static ant_value_t generator_resume_kind(
   
   GC_ROOT_PIN(js, result);
   js->active_async_coro = saved_active;
+  if (saved_active) saved_active->active_prev = NULL;
+  
   coro->active_parent = NULL;
+  coro->active_prev = NULL;
   coroutine_unhold(coro, CORO_HOLD_ACTIVE);
 
   if (is_err(result)) {
diff --git a/src/silver/ops/async.h b/src/silver/ops/async.h
index 4e6f396..7369f36 100644
--- a/src/silver/ops/async.h
+++ b/src/silver/ops/async.h
@@ -103,14 +103,22 @@ typedef struct {
 static inline void sv_async_link_activation(ant_t *js, coroutine_t *coro) {
   if (!js || !coro) return;
   coro->active_parent = js->active_async_coro;
+  coro->active_prev = NULL;
+  
+  if (js->active_async_coro) js->active_async_coro->active_prev = coro;
   js->active_async_coro = coro;
   coroutine_hold(coro, CORO_HOLD_ACTIVE);
 }
 
 static inline void sv_async_unlink_activation(ant_t *js, coroutine_t *coro) {
   if (!js || !coro) return;
-  if (js->active_async_coro == coro) js->active_async_coro = coro->active_parent;
+  
+  if (coro->active_prev) coro->active_prev->active_parent = coro->active_parent;
+  else if (js->active_async_coro == coro) js->active_async_coro = coro->active_parent;
+  if (coro->active_parent) coro->active_parent->active_prev = coro->active_prev;
+  
   coro->active_parent = NULL;
+  coro->active_prev = NULL;
   coroutine_unhold(coro, CORO_HOLD_ACTIVE);
 }
 
@@ -649,8 +657,6 @@ static inline ant_value_t sv_start_async_closure(
   return promise;
 }
 
-
-
 static inline sv_await_result_t sv_await_value(sv_vm_t *vm, ant_t *js, ant_value_t value) {
   sv_await_result_t out = {
     .state = SV_AWAIT_READY,
diff --git a/src/sugar.c b/src/sugar.c
index 1164b18..1306196 100644
--- a/src/sugar.c
+++ b/src/sugar.c
@@ -199,22 +199,34 @@ static void resume_coroutine_if_suspended(ant_t *js, coroutine_t *coro) {
     coro->sv_vm->suspended_resume_pending = true;
     
     coro->active_parent = js->active_async_coro;
+    coro->active_prev = NULL;
+    if (js->active_async_coro) js->active_async_coro->active_prev = coro;
+    
     js->active_async_coro = coro;
     coroutine_hold(coro, CORO_HOLD_ACTIVE);
     ant_value_t result = sv_resume_suspended(coro->sv_vm);
     
     coro->is_settled = false;
     if (coro->sv_vm->suspended) {
-      js->active_async_coro = coro->active_parent;
+      if (coro->active_prev) coro->active_prev->active_parent = coro->active_parent;
+      else if (js->active_async_coro == coro) js->active_async_coro = coro->active_parent;
+      if (coro->active_parent) coro->active_parent->active_prev = coro->active_prev;
+      
       coro->active_parent = NULL;
+      coro->active_prev = NULL;
       coroutine_unhold(coro, CORO_HOLD_ACTIVE);
       if (generator_resume_pending_request(js, coro, result)) return;
       coroutine_release(coro);
+      
       return;
     }
     
-    js->active_async_coro = coro->active_parent;
+    if (coro->active_prev) coro->active_prev->active_parent = coro->active_parent;
+    else if (js->active_async_coro == coro) js->active_async_coro = coro->active_parent;
+    if (coro->active_parent) coro->active_parent->active_prev = coro->active_prev;
+    
     coro->active_parent = NULL;
+    coro->active_prev = NULL;
     coroutine_unhold(coro, CORO_HOLD_ACTIVE);
     
     if (generator_resume_pending_request(js, coro, result)) {
-- 
2.51.2