stage2 提供c后端 提交stage1的测试

stage0/spl_syscall.c

@@ -423,6 +423,33 @@ static spl_vm_val_t vm_load(spl_vm_t *_vm, int nargs, spl_vm_val_t *args) {
     return (spl_vm_val_t)(uintptr_t)prog;
 }
 
+/* vm_load_from_buffer - 从内存加载字节码（comptime 内嵌 VM 用）。
+ * 参数 1 是 slice 结构 { ptr, len } 的地址（聚合参数按指针传递）。 */
+static spl_vm_val_t vm_load_from_buffer(spl_vm_t *_vm, int nargs, spl_vm_val_t *args) {
+    (void)_vm;
+    CHECK_NARGS("vm_load_from_buffer", 3);
+    spl_vm_t *vm = (spl_vm_t *)(uintptr_t)args[0];
+    const char *buf = (const char *)(uintptr_t)args[1];
+    usize len = (usize)args[2];
+    spl_prog_t *prog;
+    if (!vm || !buf)
+        return -1;
+    prog = (spl_prog_t *)malloc(sizeof(spl_prog_t));
+    if (!prog)
+        return -1;
+    if (spl_prog_load_from_buffer(buf, len, prog) != 0) {
+        free(prog);
+        return -1;
+    }
+    spl_syscall_register(prog);
+    if (spl_vm_load_prog(vm, prog) != 0) {
+        spl_prog_drop(prog);
+        free(prog);
+        return -1;
+    }
+    return 0;
+}
+
 /* vm_push - push a value onto the sub-VM's stack (for passing arguments) */
 static spl_vm_val_t vm_push(spl_vm_t *_vm, int nargs, spl_vm_val_t *args) {
     (void)_vm;
@@ -464,31 +491,36 @@ static spl_vm_val_t vm_call(spl_vm_t *_vm, int nargs, spl_vm_val_t *args) {
         fprintf(stderr, "vm_call: function '%s' not found\n", name);
         return -1;
     }
-    if (vm->cp >= vm->config.max_call_depth - 1) {
+    if (vm->cp >= vm->config.max_call_depth) {
         fprintf(stderr, "vm_call: call stack overflow\n");
         return -1;
     }
 
-    /* Sentinel frame so the entry function's RET halts cleanly */
-    if (vm->cp == 0) {
-        vm->frames.data[vm->cp].saved_fp = 0;
-        vm->frames.data[vm->cp].saved_ip = (uintptr_t)-1;
-        vm->frames.data[vm->cp].nargs = 0;
-        vm->cp++;
-    }
-
-    /* Actual call frame (same logic as the CALL instruction) */
-    vm->frames.data[vm->cp].saved_fp = vm->fp;
-    vm->frames.data[vm->cp].saved_ip = vm->ip;
-    vm->frames.data[vm->cp].nargs = call_nargs;
-    vm->cp++;
-    vm->fp = vm->sp - call_nargs;
+    /* 入口调用：ip 置 -1 作为 sentinel，RET 时 halt 并把返回值写入 exit_code。
+     * 实参须已由 vm_push 压栈（sp = nargs）。 */
+    vm->ip = (uintptr_t)-1;
+    vm->cp = 0;
+    vm->fp = 0;
+    vm->frames.data[0].saved_sp = vm->sp - call_nargs;
+    vm->frames.data[0].saved_fp = vm->fp;
+    vm->frames.data[0].saved_ip = vm->ip;
+    vm->frames.data[0].nargs = call_nargs;
+    vm->cp = 1;
     vm->ip = (uintptr_t)func->address;
+    vm->fp = vm->sp - call_nargs;
     return 0;
 }
 
-/* vm_run - run a sub-VM to completion, returns exit_code */
-SYSCALL_1(vm_run, spl_vm_t *, spl_vm_run_until(a1, 0))
+/* vm_run - run a sub-VM to completion, returns exit_code（入口 RET 的值） */
+static spl_vm_val_t vm_run(spl_vm_t *_vm, int nargs, spl_vm_val_t *args) {
+    (void)_vm;
+    CHECK_NARGS("vm_run", 1);
+    spl_vm_t *vm = (spl_vm_t *)(uintptr_t)args[0];
+    if (!vm)
+        return -1;
+    spl_vm_run_until(vm, 0);
+    return (spl_vm_val_t)vm->exit_code;
+}
 
 /* =================================================================
  * Registration
@@ -1163,6 +1195,7 @@ void spl_syscall_register(spl_prog_t *prog) {
         {"vm_new", 0, vm_new},
         {"vm_drop", 0, vm_drop},
         {"vm_load", 0, vm_load},
+        {"vm_load_from_buffer", 0, vm_load_from_buffer},
         {"vm_push", 0, vm_push},
         {"vm_call", 0, vm_call},
         {"vm_run", 0, vm_run},