From 62fc486c20b128459119318d2d5162d0c67d9e95 Mon Sep 17 00:00:00 2001
From: Wenyong Huang <wenyong.huang@intel.com>
Date: Fri, 7 Apr 2023 06:47:24 +0800
Subject: [PATCH] Refine aot compiler check suspend_flags and fix issue of
 multi-tier jit (#2111)

In LLVM AOT/JIT compiler, only need to check the suspend_flags when memory is
a shared memory since the shared memory must be enabled for multi-threading,
so as not to impact the performance in non-multi-threading memory mode. Also
refine the LLVM IRs to check the suspend_flags.

And fix an issue of multi-tier jit for multi-threading, the instance of the child thread
should be removed from the instance list before it is de-instantiated.
---
 core/iwasm/compilation/aot_emit_control.c | 36 +++++++++++------------
 core/iwasm/interpreter/wasm_runtime.c     |  2 +-
 2 files changed, 18 insertions(+), 20 deletions(-)

diff --git a/core/iwasm/compilation/aot_emit_control.c b/core/iwasm/compilation/aot_emit_control.c
index 68c286f4..8c15d4d1 100644
--- a/core/iwasm/compilation/aot_emit_control.c
+++ b/core/iwasm/compilation/aot_emit_control.c
@@ -671,9 +671,16 @@ bool
 check_suspend_flags(AOTCompContext *comp_ctx, AOTFuncContext *func_ctx)
 {
     LLVMValueRef terminate_addr, terminate_flags, flag, offset, res;
-    LLVMBasicBlockRef terminate_check_block, non_terminate_block;
+    LLVMBasicBlockRef terminate_block, non_terminate_block;
     AOTFuncType *aot_func_type = func_ctx->aot_func->func_type;
-    LLVMBasicBlockRef terminate_block;
+    bool is_shared_memory =
+        comp_ctx->comp_data->memories[0].memory_flags & 0x02 ? true : false;
+
+    /* Only need to check the suspend flags when memory is shared since
+       shared memory must be enabled for multi-threading */
+    if (!is_shared_memory) {
+        return true;
+    }
 
     /* Offset of suspend_flags */
     offset = I32_FIVE;
@@ -701,29 +708,20 @@ check_suspend_flags(AOTCompContext *comp_ctx, AOTFuncContext *func_ctx)
         will always be loaded from memory rather than register */
     LLVMSetVolatile(terminate_flags, true);
 
-    CREATE_BLOCK(terminate_check_block, "terminate_check");
-    MOVE_BLOCK_AFTER_CURR(terminate_check_block);
-
-    CREATE_BLOCK(non_terminate_block, "non_terminate");
-    MOVE_BLOCK_AFTER_CURR(non_terminate_block);
-
-    BUILD_ICMP(LLVMIntSGT, terminate_flags, I32_ZERO, res, "need_terminate");
-    BUILD_COND_BR(res, terminate_check_block, non_terminate_block);
-
-    /* Move builder to terminate check block */
-    SET_BUILDER_POS(terminate_check_block);
-
-    CREATE_BLOCK(terminate_block, "terminate");
-    MOVE_BLOCK_AFTER_CURR(terminate_block);
-
     if (!(flag = LLVMBuildAnd(comp_ctx->builder, terminate_flags, I32_ONE,
                               "termination_flag"))) {
         aot_set_last_error("llvm build AND failed");
         return false;
     }
 
-    BUILD_ICMP(LLVMIntSGT, flag, I32_ZERO, res, "need_terminate");
-    BUILD_COND_BR(res, terminate_block, non_terminate_block);
+    CREATE_BLOCK(non_terminate_block, "non_terminate");
+    MOVE_BLOCK_AFTER_CURR(non_terminate_block);
+
+    CREATE_BLOCK(terminate_block, "terminate");
+    MOVE_BLOCK_AFTER_CURR(terminate_block);
+
+    BUILD_ICMP(LLVMIntEQ, flag, I32_ZERO, res, "flag_terminate");
+    BUILD_COND_BR(res, non_terminate_block, terminate_block);
 
     /* Move builder to terminate block */
     SET_BUILDER_POS(terminate_block);
diff --git a/core/iwasm/interpreter/wasm_runtime.c b/core/iwasm/interpreter/wasm_runtime.c
index 8130d90a..29365024 100644
--- a/core/iwasm/interpreter/wasm_runtime.c
+++ b/core/iwasm/interpreter/wasm_runtime.c
@@ -2178,7 +2178,7 @@ wasm_deinstantiate(WASMModuleInstance *module_inst, bool is_sub_inst)
        func_ptrs and fast_jit_func_ptrs of the instance, to avoid
        accessing the freed memory in the jit backend compilation
        threads */
-    if (!is_sub_inst) {
+    {
         WASMModule *module = module_inst->module;
         WASMModuleInstance *instance_prev = NULL, *instance;
         os_mutex_lock(&module->instance_list_lock);