mach disrupt support

2026-02-06 21:09:18 -06:00
parent 77ae133747
commit 6571262af0
1 changed files with 155 additions and 75 deletions
--- a/source/quickjs.c
+++ b/source/quickjs.c
@@ -556,7 +556,7 @@ typedef enum MachOpcode {

  /* Special */
  MACH_TYPEOF,        /* R(A) = typeof R(B) */
-  MACH_THROW,         /* throw R(A) */
+  MACH_THROW,         /* disrupt — trigger disruption */

  MACH_NOP,

@@ -613,7 +613,7 @@ static const char *mach_opcode_names[MACH_OP_COUNT] = {
  [MACH_NEWARRAY] = "newarray",
  [MACH_CLOSURE] = "closure",
  [MACH_TYPEOF] = "typeof",
-  [MACH_THROW] = "throw",
+  [MACH_THROW] = "disrupt",
  [MACH_NOP] = "nop",
 };

@@ -642,6 +642,7 @@ typedef struct JSCodeRegister {
  MachLineEntry *line_table;  /* [instr_count], parallel to instructions[] */
  char *filename_cstr;        /* plain C string for stack trace (js_malloc_rt) */
  char *name_cstr;            /* plain C string for stack trace (js_malloc_rt) */
+  uint16_t disruption_pc;     /* start of disruption handler (0 = none) */
 } JSCodeRegister;

 /* Pre-parsed MCODE for a single function (off-heap, never GC'd).
@@ -664,6 +665,7 @@ typedef struct JSMCode {
  MachLineEntry *line_table;  /* [instr_count], parallel to instrs[] */
  const char *name;           /* function name (points into cJSON tree) */
  const char *filename;       /* source filename (points into cJSON tree) */
+  uint16_t disruption_pc;     /* start of disruption handler (0 = none) */
 } JSMCode;

 /* Frame for closures - used by link-time relocation model where closures
@@ -30632,6 +30634,7 @@ typedef struct MachCode {
  char *name;  /* owned C string, or NULL */
  MachLineEntry *line_table;  /* [instr_count], parallel to instructions[] */
  char *filename;             /* source filename (sys_malloc'd) */
+  uint16_t disruption_pc;     /* start of disruption handler (0 = none) */
 } MachCode;

 /* ---- Compiler state ---- */
@@ -31384,6 +31387,17 @@ static int mach_compile_expr(MachCompState *cs, cJSON *node, int dest) {
    /* Implicit return null */
    mach_emit(&child, MACH_ABC(MACH_RETNIL, 0, 0, 0));

+    /* Disruption clause — emitted after body, recorded as disruption_pc */
+    int disruption_start = 0;
+    cJSON *disruption = cJSON_GetObjectItem(node, "disruption");
+    if (disruption && cJSON_IsArray(disruption)) {
+      disruption_start = mach_current_pc(&child);
+      int dcount = cJSON_GetArraySize(disruption);
+      for (int i = 0; i < dcount; i++)
+        mach_compile_stmt(&child, cJSON_GetArrayItem(disruption, i));
+      mach_emit(&child, MACH_ABC(MACH_RETNIL, 0, 0, 0));
+    }
+
    /* Build MachCode for the child function */
    cJSON *fn_scope = mach_find_scope_record(cs->scopes, child.function_nr);
    cJSON *fn_ncs = fn_scope ? cJSON_GetObjectItem(fn_scope, "nr_close_slots") : NULL;
@@ -31401,6 +31415,7 @@ static int mach_compile_expr(MachCompState *cs, cJSON *node, int dest) {
    fn_code->functions = child.functions;
    fn_code->line_table = child.line_info;
    fn_code->filename = cs->filename ? strdup(cs->filename) : NULL;
+    fn_code->disruption_pc = disruption_start;

    cJSON *fname = cJSON_GetObjectItem(node, "name");
    if (fname && cJSON_IsString(fname)) {
@@ -31823,6 +31838,8 @@ JSCodeRegister *JS_LoadMachCode(JSContext *ctx, MachCode *mc, JSValue env) {
  code->filename_cstr = mc->filename ? js_strdup_rt(mc->filename) : NULL;
  code->name_cstr = mc->name ? js_strdup_rt(mc->name) : NULL;

+  code->disruption_pc = mc->disruption_pc;
+
  /* Link: resolve GETNAME to GETENV/GETINTRINSIC */
  mach_link_code(ctx, code, env);

@@ -31960,59 +31977,63 @@ static JSValue reg_vm_binop(JSContext *ctx, int op, JSValue a, JSValue b) {
    }
  }

-  /* Float operations */
-  double da, db;
-  if (JS_ToFloat64(ctx, &da, a) || JS_ToFloat64(ctx, &db, b))
-    return JS_EXCEPTION;
+  /* String concat for ADD */
+  if (op == MACH_ADD && JS_IsText(a) && JS_IsText(b))
+    return JS_ConcatString(ctx, a, b);

-  switch (op) {
-  case MACH_ADD:
-    return JS_NewFloat64(ctx, da + db);
-  case MACH_SUB:
-    return JS_NewFloat64(ctx, da - db);
-  case MACH_MUL:
-    return JS_NewFloat64(ctx, da * db);
-  case MACH_DIV:
-    return JS_NewFloat64(ctx, da / db);
-  case MACH_MOD:
-    return JS_NewFloat64(ctx, fmod(da, db));
-  case MACH_POW:
-    return JS_NewFloat64(ctx, pow(da, db));
-  case MACH_EQ:
-    return JS_NewBool(ctx, da == db);
-  case MACH_NEQ:
-    return JS_NewBool(ctx, da != db);
-  case MACH_LT:
-    return JS_NewBool(ctx, da < db);
-  case MACH_LE:
-    return JS_NewBool(ctx, da <= db);
-  case MACH_GT:
-    return JS_NewBool(ctx, da > db);
-  case MACH_GE:
-    return JS_NewBool(ctx, da >= db);
-  case MACH_BAND:
-  case MACH_BOR:
-  case MACH_BXOR:
-  case MACH_SHL:
-  case MACH_SHR:
-  case MACH_USHR: {
-    int32_t ia = (int32_t)da;
-    int32_t ib = (int32_t)db;
+  /* Comparison ops allow mixed types — return false for mismatches */
+  if (op >= MACH_EQ && op <= MACH_GE) {
+    if (JS_IsNumber(a) && JS_IsNumber(b)) {
+      double da, db;
+      JS_ToFloat64(ctx, &da, a);
+      JS_ToFloat64(ctx, &db, b);
+      switch (op) {
+      case MACH_EQ: return JS_NewBool(ctx, da == db);
+      case MACH_NEQ: return JS_NewBool(ctx, da != db);
+      case MACH_LT: return JS_NewBool(ctx, da < db);
+      case MACH_LE: return JS_NewBool(ctx, da <= db);
+      case MACH_GT: return JS_NewBool(ctx, da > db);
+      case MACH_GE: return JS_NewBool(ctx, da >= db);
+      default: break;
+      }
+    }
+    /* Different types: EQ→false, NEQ→true, others→false */
+    if (op == MACH_NEQ) return JS_NewBool(ctx, 1);
+    return JS_NewBool(ctx, 0);
+  }
+
+  /* Numeric operations — both must be numeric */
+  if (JS_IsNumber(a) && JS_IsNumber(b)) {
+    double da, db;
+    JS_ToFloat64(ctx, &da, a);
+    JS_ToFloat64(ctx, &db, b);
    switch (op) {
-    case MACH_BAND: return JS_NewInt32(ctx, ia & ib);
-    case MACH_BOR: return JS_NewInt32(ctx, ia | ib);
-    case MACH_BXOR: return JS_NewInt32(ctx, ia ^ ib);
-    case MACH_SHL: return JS_NewInt32(ctx, ia << (ib & 31));
-    case MACH_SHR: return JS_NewInt32(ctx, ia >> (ib & 31));
-    case MACH_USHR: return JS_NewInt32(ctx, (uint32_t)ia >> (ib & 31));
+    case MACH_ADD: return JS_NewFloat64(ctx, da + db);
+    case MACH_SUB: return JS_NewFloat64(ctx, da - db);
+    case MACH_MUL: return JS_NewFloat64(ctx, da * db);
+    case MACH_DIV: return JS_NewFloat64(ctx, da / db);
+    case MACH_MOD: return JS_NewFloat64(ctx, fmod(da, db));
+    case MACH_POW: return JS_NewFloat64(ctx, pow(da, db));
+    case MACH_BAND: case MACH_BOR: case MACH_BXOR:
+    case MACH_SHL: case MACH_SHR: case MACH_USHR: {
+      int32_t ia = (int32_t)da;
+      int32_t ib = (int32_t)db;
+      switch (op) {
+      case MACH_BAND: return JS_NewInt32(ctx, ia & ib);
+      case MACH_BOR: return JS_NewInt32(ctx, ia | ib);
+      case MACH_BXOR: return JS_NewInt32(ctx, ia ^ ib);
+      case MACH_SHL: return JS_NewInt32(ctx, ia << (ib & 31));
+      case MACH_SHR: return JS_NewInt32(ctx, ia >> (ib & 31));
+      case MACH_USHR: return JS_NewInt32(ctx, (uint32_t)ia >> (ib & 31));
+      default: break;
+      }
+    }
    default: break;
    }
  }
-  default:
-    break;
-  }

-  return JS_NULL;
+  /* Type mismatch — disrupt */
+  return JS_EXCEPTION;
 }

 /* Check for interrupt */
@@ -32132,6 +32153,7 @@ static JSValue JS_CallRegisterVM(JSContext *ctx, JSCodeRegister *code,
      JSValue right = frame->slots[c];
      JSValue res = reg_vm_binop(ctx, op, left, right);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
+      if (JS_IsException(res)) { goto disrupt; }
      frame->slots[a] = res;
      break;
    }
@@ -32358,8 +32380,7 @@ static JSValue JS_CallRegisterVM(JSContext *ctx, JSCodeRegister *code,
      JSValue func_val = frame->slots[base];

      if (!JS_IsFunction(func_val)) {
-        result = JS_ThrowTypeError(ctx, "not a function");
-        goto done;
+        goto disrupt;
      }

      JSFunction *fn = JS_VALUE_GET_FUNCTION(func_val);
@@ -32370,13 +32391,13 @@ static JSValue JS_CallRegisterVM(JSContext *ctx, JSCodeRegister *code,
        JSValue ret = js_call_c_function(ctx, func_val, JS_NULL, nargs, &frame->slots[base + 1]);
        frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
        ctx->reg_current_frame = JS_NULL;
-        if (JS_IsException(ret)) { result = ret; goto done; }
+        if (JS_IsException(ret)) { goto disrupt; }
        if (nresults > 0) frame->slots[base] = ret;
      } else if (fn->kind == JS_FUNC_KIND_REGISTER) {
        /* Register function: allocate frame, copy args, switch */
        JSCodeRegister *fn_code = fn->u.reg.code;
        JSFrameRegister *new_frame = alloc_frame_register(ctx, fn_code->nr_slots);
-        if (!new_frame) { result = JS_EXCEPTION; goto done; }
+        if (!new_frame) { goto disrupt; }
        /* Re-read pointers — GC may have moved them */
        frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
        func_val = frame->slots[base];
@@ -32400,7 +32421,7 @@ static JSValue JS_CallRegisterVM(JSContext *ctx, JSCodeRegister *code,
        /* Other function kinds (bytecode) — call via C bridge */
        JSValue ret = js_call_c_function(ctx, func_val, JS_NULL, nargs, &frame->slots[base + 1]);
        frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
-        if (JS_IsException(ret)) { result = ret; goto done; }
+        if (JS_IsException(ret)) { goto disrupt; }
        if (nresults > 0) frame->slots[base] = ret;
      }
      break;
@@ -32445,7 +32466,7 @@ static JSValue JS_CallRegisterVM(JSContext *ctx, JSCodeRegister *code,
    case MACH_NEWOBJECT: {
      JSValue obj = JS_NewObject(ctx);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
-      if (JS_IsException(obj)) { result = obj; goto done; }
+      if (JS_IsException(obj)) { goto disrupt; }
      frame->slots[a] = obj;
      break;
    }
@@ -32454,7 +32475,7 @@ static JSValue JS_CallRegisterVM(JSContext *ctx, JSCodeRegister *code,
      int count = b;
      JSValue arr = JS_NewArray(ctx);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
-      if (JS_IsException(arr)) { result = arr; goto done; }
+      if (JS_IsException(arr)) { goto disrupt; }
      for (int i = 0; i < count; i++) {
        JS_SetPropertyUint32(ctx, arr, i, frame->slots[a + 1 + i]);
        frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
@@ -32477,13 +32498,34 @@ static JSValue JS_CallRegisterVM(JSContext *ctx, JSCodeRegister *code,
    }

    case MACH_THROW:
-      result = JS_Throw(ctx, frame->slots[a]);
-      goto done;
+      goto disrupt;

    default:
      result = JS_ThrowInternalError(ctx, "unknown register VM opcode %d", op);
      goto done;
    }
+    continue;
+
+  disrupt:
+    /* Search frame chain for a disruption handler */
+    for (;;) {
+      JSFunction *fn = JS_VALUE_GET_FUNCTION(frame->function);
+      code = fn->u.reg.code;
+      if (code->disruption_pc > 0) {
+        env = fn->u.reg.env_record;
+        pc = code->disruption_pc;
+        break;
+      }
+      if (JS_IsNull(frame->caller)) {
+        result = JS_NULL;
+        goto done;
+      }
+      /* Unwind one frame */
+      JSFrameRegister *caller = (JSFrameRegister *)JS_VALUE_GET_PTR(frame->caller);
+      frame->caller = JS_NULL;
+      frame = caller;
+      frame_ref.val = JS_MKPTR(frame);
+    }
  }

 done:
@@ -33735,10 +33777,14 @@ static cJSON *mach_gen_function (MachGenState *parent, cJSON *func_node) {
  mach_gen_emit_0 (&s, "return_undef");

  /* Compile disruption clause if present */
+  int disruption_start = 0;
  cJSON *disruption = cJSON_GetObjectItem (func_node, "disruption");
  if (disruption && cJSON_IsArray (disruption)) {
+    disruption_start = cJSON_GetArraySize (s.instructions);
    cJSON_ArrayForEach (stmt, disruption) { mach_gen_statement (&s, stmt); }
+    mach_gen_emit_0 (&s, "return_undef");
  }
+  cJSON_AddNumberToObject (result, "disruption_pc", disruption_start);

  cJSON *fn_scope = mach_find_scope_record (s.scopes, s.function_nr);
  cJSON *fn_ncs = fn_scope ? cJSON_GetObjectItem (fn_scope, "nr_close_slots") : NULL;
@@ -33956,6 +34002,10 @@ static JSMCode *jsmcode_parse_one(cJSON *func_def) {
  code->name = cJSON_GetStringValue(cJSON_GetObjectItem(func_def, "name"));
  code->filename = cJSON_GetStringValue(cJSON_GetObjectItem(func_def, "filename"));

+  /* Extract disruption_pc */
+  cJSON *dpc = cJSON_GetObjectItem(func_def, "disruption_pc");
+  code->disruption_pc = dpc ? (uint16_t)cJSON_GetNumberValue(dpc) : 0;
+
  return code;
 }

@@ -34137,9 +34187,9 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
      int dest = (int)a1->valuedouble;
      JSValue left = frame->slots[(int)a2->valuedouble];
      JSValue right = frame->slots[(int)a3->valuedouble];
-      /* Use the same binop helper as the register VM for correct int/float handling */
      JSValue res = reg_vm_binop(ctx, MACH_ADD, left, right);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
+      if (JS_IsException(res)) { goto disrupt; }
      frame->slots[dest] = res;
    }
    else if (strcmp(op, "sub") == 0) {
@@ -34148,6 +34198,7 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
      JSValue right = frame->slots[(int)a3->valuedouble];
      JSValue res = reg_vm_binop(ctx, MACH_SUB, left, right);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
+      if (JS_IsException(res)) { goto disrupt; }
      frame->slots[dest] = res;
    }
    else if (strcmp(op, "mul") == 0) {
@@ -34156,6 +34207,7 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
      JSValue right = frame->slots[(int)a3->valuedouble];
      JSValue res = reg_vm_binop(ctx, MACH_MUL, left, right);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
+      if (JS_IsException(res)) { goto disrupt; }
      frame->slots[dest] = res;
    }
    else if (strcmp(op, "div") == 0) {
@@ -34164,6 +34216,7 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
      JSValue right = frame->slots[(int)a3->valuedouble];
      JSValue res = reg_vm_binop(ctx, MACH_DIV, left, right);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
+      if (JS_IsException(res)) { goto disrupt; }
      frame->slots[dest] = res;
    }
    else if (strcmp(op, "mod") == 0) {
@@ -34172,6 +34225,7 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
      JSValue right = frame->slots[(int)a3->valuedouble];
      JSValue res = reg_vm_binop(ctx, MACH_MOD, left, right);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
+      if (JS_IsException(res)) { goto disrupt; }
      frame->slots[dest] = res;
    }
    else if (strcmp(op, "pow") == 0) {
@@ -34180,6 +34234,7 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
      JSValue right = frame->slots[(int)a3->valuedouble];
      JSValue res = reg_vm_binop(ctx, MACH_POW, left, right);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
+      if (JS_IsException(res)) { goto disrupt; }
      frame->slots[dest] = res;
    }
    else if (strcmp(op, "neg") == 0) {
@@ -34337,36 +34392,42 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
      int dest = (int)a1->valuedouble;
      JSValue res = reg_vm_binop(ctx, MACH_BAND, frame->slots[(int)a2->valuedouble], frame->slots[(int)a3->valuedouble]);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
+      if (JS_IsException(res)) { goto disrupt; }
      frame->slots[dest] = res;
    }
    else if (strcmp(op, "bitor") == 0) {
      int dest = (int)a1->valuedouble;
      JSValue res = reg_vm_binop(ctx, MACH_BOR, frame->slots[(int)a2->valuedouble], frame->slots[(int)a3->valuedouble]);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
+      if (JS_IsException(res)) { goto disrupt; }
      frame->slots[dest] = res;
    }
    else if (strcmp(op, "bitxor") == 0) {
      int dest = (int)a1->valuedouble;
      JSValue res = reg_vm_binop(ctx, MACH_BXOR, frame->slots[(int)a2->valuedouble], frame->slots[(int)a3->valuedouble]);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
+      if (JS_IsException(res)) { goto disrupt; }
      frame->slots[dest] = res;
    }
    else if (strcmp(op, "shl") == 0) {
      int dest = (int)a1->valuedouble;
      JSValue res = reg_vm_binop(ctx, MACH_SHL, frame->slots[(int)a2->valuedouble], frame->slots[(int)a3->valuedouble]);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
+      if (JS_IsException(res)) { goto disrupt; }
      frame->slots[dest] = res;
    }
    else if (strcmp(op, "shr") == 0) {
      int dest = (int)a1->valuedouble;
      JSValue res = reg_vm_binop(ctx, MACH_SHR, frame->slots[(int)a2->valuedouble], frame->slots[(int)a3->valuedouble]);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
+      if (JS_IsException(res)) { goto disrupt; }
      frame->slots[dest] = res;
    }
    else if (strcmp(op, "ushr") == 0) {
      int dest = (int)a1->valuedouble;
      JSValue res = reg_vm_binop(ctx, MACH_USHR, frame->slots[(int)a2->valuedouble], frame->slots[(int)a3->valuedouble]);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
+      if (JS_IsException(res)) { goto disrupt; }
      frame->slots[dest] = res;
    }

@@ -34541,15 +34602,14 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
      int call_argc = a3 ? (int)a3->valuedouble : 0;

      if (!JS_IsFunction(func_val)) {
-        result = JS_ThrowTypeError(ctx, "not a function");
-        goto done;
+        goto disrupt;
      }

      JSFunction *fn = JS_VALUE_GET_FUNCTION(func_val);
      if (fn->kind == JS_FUNC_KIND_MCODE) {
        JSMCode *fn_code = fn->u.mcode.code;
        JSFrameRegister *new_frame = alloc_frame_register(ctx, fn_code->nr_slots);
-        if (!new_frame) { result = JS_EXCEPTION; goto done; }
+        if (!new_frame) { goto disrupt; }
        frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
        /* Re-read func_val after GC may have moved it */
        func_val = frame->slots[(int)a2->valuedouble];
@@ -34602,7 +34662,7 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
        JSValue this_val = JS_NULL;
        result = JS_Call(ctx, target, this_val, c_argc, c_argv);
        frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
-        if (JS_IsException(result)) goto done;
+        if (JS_IsException(result)) goto disrupt;
        frame->slots[ret_reg] = result;
      } else {
        /* MCODE function — switch frames */
@@ -34632,7 +34692,7 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
          JSValue c_result = js_call_c_function(ctx, new_frame->function, new_frame->slots[0], c_argc, c_argv);
          frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
          ctx->reg_current_frame = JS_NULL;
-          if (JS_IsException(c_result)) { result = c_result; goto done; }
+          if (JS_IsException(c_result)) { goto disrupt; }
          frame->slots[ret_reg] = c_result;
        } else {
          /* Bytecode interop — use JS_Call */
@@ -34641,7 +34701,7 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
          /* TODO: proper arg count */
          JSValue bc_result = JS_Call(ctx, new_frame->function, new_frame->slots[0], bc_argc, bc_argv);
          frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
-          if (JS_IsException(bc_result)) { result = bc_result; goto done; }
+          if (JS_IsException(bc_result)) { goto disrupt; }
          frame->slots[ret_reg] = bc_result;
        }
      }
@@ -34654,14 +34714,13 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
      JSValue func_val = frame->slots[func_reg];

      if (!JS_IsFunction(func_val)) {
-        result = JS_ThrowTypeError(ctx, "not a function");
-        goto done;
+        goto disrupt;
      }
      JSFunction *fn = JS_VALUE_GET_FUNCTION(func_val);
      if (fn->kind == JS_FUNC_KIND_MCODE) {
        JSMCode *fn_code = fn->u.mcode.code;
        JSFrameRegister *new_frame = alloc_frame_register(ctx, fn_code->nr_slots);
-        if (!new_frame) { result = JS_EXCEPTION; goto done; }
+        if (!new_frame) { goto disrupt; }
        frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
        func_val = frame->slots[func_reg]; /* re-read after GC */
        new_frame->function = func_val;
@@ -34677,15 +34736,14 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,

      if (JS_IsFunction(target)) {
        result = JS_ThrowInternalError(ctx, "C function tail call not supported in MCODE");
-        goto done;
+        goto disrupt;
      }

      JSFrameRegister *new_frame = (JSFrameRegister *)JS_VALUE_GET_PTR(target);
      JSFunction *fn = JS_VALUE_GET_FUNCTION(new_frame->function);

      if (fn->kind != JS_FUNC_KIND_MCODE) {
-        result = JS_ThrowInternalError(ctx, "non-mcode function in goinvoke");
-        goto done;
+        goto disrupt;
      }

      /* Tail call — bypass current frame */
@@ -34738,14 +34796,14 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
      int dest = (int)a1->valuedouble;
      JSValue rec = JS_NewObject(ctx);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
-      if (JS_IsException(rec)) { result = rec; goto done; }
+      if (JS_IsException(rec)) { goto disrupt; }
      frame->slots[dest] = rec;
    }
    else if (strcmp(op, "mkarray") == 0) {
      int dest = (int)a1->valuedouble;
      JSValue arr = JS_NewArray(ctx);
      frame = (JSFrameRegister *)JS_VALUE_GET_PTR(frame_ref.val);
-      if (JS_IsException(arr)) { result = arr; goto done; }
+      if (JS_IsException(arr)) { goto disrupt; }
      frame->slots[dest] = arr;
    }
    else if (strcmp(op, "mkfunc") == 0) {
@@ -34779,8 +34837,7 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,

    /* ---- Disruption ---- */
    else if (strcmp(op, "disrupt") == 0) {
-      result = JS_Throw(ctx, JS_NULL);
-      goto done;
+      goto disrupt;
    }

    /* ---- Unknown opcode ---- */
@@ -34788,6 +34845,27 @@ static JSValue mcode_exec(JSContext *ctx, JSMCode *code, JSValue this_obj,
      result = JS_ThrowInternalError(ctx, "unknown MCODE opcode: %s", op);
      goto done;
    }
+    continue;
+
+  disrupt:
+    /* Search frame chain for a disruption handler */
+    for (;;) {
+      JSFunction *fn = JS_VALUE_GET_FUNCTION(frame->function);
+      JSMCode *fn_code = fn->u.mcode.code;
+      if (fn_code->disruption_pc > 0) {
+        code = fn_code;
+        pc = fn_code->disruption_pc;
+        break;
+      }
+      if (JS_IsNull(frame->caller)) {
+        result = JS_NULL;
+        goto done;
+      }
+      JSFrameRegister *caller = (JSFrameRegister *)JS_VALUE_GET_PTR(frame->caller);
+      frame->caller = JS_NULL;
+      frame = caller;
+      frame_ref.val = JS_MKPTR(frame);
+    }
  }

 done:
@@ -34963,6 +35041,8 @@ static void dump_register_code(JSContext *ctx, JSCodeRegister *code, int indent)
  if (!JS_IsNull(code->name)) {
    JS_FreeCString(ctx, name);
  }
+  if (code->disruption_pc > 0)
+    printf("%s  Disruption handler at: %d\n", pad, code->disruption_pc);

  /* Constant pool */
  if (code->cpool_count > 0) {