From 2eed50b3034b8eec531cce4a782b8c698fea00fd Mon Sep 17 00:00:00 2001
From: Enrico Loparco <eloparco@amazon.com>
Date: Fri, 27 Jan 2023 11:32:33 +0100
Subject: [PATCH] Document how to use WASI threads in AOT mode (#1905)

Describe how to use WASI threads in AOT mode, following the discussion below:
  https://github.com/bytecodealliance/wasm-micro-runtime/pull/1867#discussion_r1070268062

Make aux stack boundary checks of wasi-threads always successful by setting
`exec_env->aux_stack_bottom` to UINT32_MAX and `exec_env->aux_stack_boundary` to 0
---
 core/iwasm/interpreter/wasm_interp_classic.c  | 20 ++++++++-----------
 core/iwasm/interpreter/wasm_interp_fast.c     | 20 ++++++++-----------
 .../libraries/thread-mgr/thread_manager.c     |  5 +++++
 samples/wasi-threads/README.md                |  9 ++++++++-
 4 files changed, 29 insertions(+), 25 deletions(-)

diff --git a/core/iwasm/interpreter/wasm_interp_classic.c b/core/iwasm/interpreter/wasm_interp_classic.c
index 06d75a48..3e16b380 100644
--- a/core/iwasm/interpreter/wasm_interp_classic.c
+++ b/core/iwasm/interpreter/wasm_interp_classic.c
@@ -1780,18 +1780,14 @@ wasm_interp_call_func_bytecode(WASMModuleInstance *module,
                 global = globals + global_idx;
                 global_addr = get_global_addr(global_data, global);
                 aux_stack_top = *(uint32 *)(frame_sp - 1);
-                if (wasm_exec_env_is_aux_stack_managed_by_runtime(exec_env)) {
-                    if (aux_stack_top
-                        <= exec_env->aux_stack_boundary.boundary) {
-                        wasm_set_exception(module,
-                                           "wasm auxiliary stack overflow");
-                        goto got_exception;
-                    }
-                    if (aux_stack_top > exec_env->aux_stack_bottom.bottom) {
-                        wasm_set_exception(module,
-                                           "wasm auxiliary stack underflow");
-                        goto got_exception;
-                    }
+                if (aux_stack_top <= exec_env->aux_stack_boundary.boundary) {
+                    wasm_set_exception(module, "wasm auxiliary stack overflow");
+                    goto got_exception;
+                }
+                if (aux_stack_top > exec_env->aux_stack_bottom.bottom) {
+                    wasm_set_exception(module,
+                                       "wasm auxiliary stack underflow");
+                    goto got_exception;
                 }
                 *(int32 *)global_addr = aux_stack_top;
                 frame_sp--;
diff --git a/core/iwasm/interpreter/wasm_interp_fast.c b/core/iwasm/interpreter/wasm_interp_fast.c
index adcb18c2..0ea920f2 100644
--- a/core/iwasm/interpreter/wasm_interp_fast.c
+++ b/core/iwasm/interpreter/wasm_interp_fast.c
@@ -1576,18 +1576,14 @@ wasm_interp_call_func_bytecode(WASMModuleInstance *module,
                 global = globals + global_idx;
                 global_addr = get_global_addr(global_data, global);
                 aux_stack_top = frame_lp[GET_OFFSET()];
-                if (wasm_exec_env_is_aux_stack_managed_by_runtime(exec_env)) {
-                    if (aux_stack_top
-                        <= exec_env->aux_stack_boundary.boundary) {
-                        wasm_set_exception(module,
-                                           "wasm auxiliary stack overflow");
-                        goto got_exception;
-                    }
-                    if (aux_stack_top > exec_env->aux_stack_bottom.bottom) {
-                        wasm_set_exception(module,
-                                           "wasm auxiliary stack underflow");
-                        goto got_exception;
-                    }
+                if (aux_stack_top <= exec_env->aux_stack_boundary.boundary) {
+                    wasm_set_exception(module, "wasm auxiliary stack overflow");
+                    goto got_exception;
+                }
+                if (aux_stack_top > exec_env->aux_stack_bottom.bottom) {
+                    wasm_set_exception(module,
+                                       "wasm auxiliary stack underflow");
+                    goto got_exception;
                 }
                 *(int32 *)global_addr = aux_stack_top;
 #if WASM_ENABLE_MEMORY_PROFILING != 0
diff --git a/core/iwasm/libraries/thread-mgr/thread_manager.c b/core/iwasm/libraries/thread-mgr/thread_manager.c
index 492ed66b..8ec310d9 100644
--- a/core/iwasm/libraries/thread-mgr/thread_manager.c
+++ b/core/iwasm/libraries/thread-mgr/thread_manager.c
@@ -586,6 +586,11 @@ wasm_cluster_create_thread(WASMExecEnv *exec_env,
             goto fail3;
         }
     }
+    else {
+        /* Disable aux stack */
+        new_exec_env->aux_stack_boundary.boundary = 0;
+        new_exec_env->aux_stack_bottom.bottom = UINT32_MAX;
+    }
 
     if (!wasm_cluster_add_exec_env(cluster, new_exec_env))
         goto fail3;
diff --git a/samples/wasi-threads/README.md b/samples/wasi-threads/README.md
index 533f687e..499162b6 100644
--- a/samples/wasi-threads/README.md
+++ b/samples/wasi-threads/README.md
@@ -10,7 +10,7 @@ make \
     THREAD_MODEL=posix
 ```
 
-Build and run the samples
+## Build and run the samples
 
 ```shell
 $ mkdir build
@@ -22,3 +22,10 @@ $ ./iwasm wasm-apps/no_pthread.wasm
 ...
 $ ./iwasm wasm-apps/exception_propagation.wasm
 ```
+
+## Run samples in AOT mode
+```shell
+$ ../../../wamr-compiler/build/wamrc \
+    -o wasm-apps/no_pthread.aot wasm-apps/no_pthread.wasm
+$ ./iwasm wasm-apps/no_pthread.aot
+```