perf: 对象字面量批量构造键序预建 shape

crates/oxide_ir/src/contract.rs

@@ -756,6 +756,8 @@ mod tests {
         assert_contract(OpCode::IC_GET_PROP, Some(1), &[1, 2], false);
         assert_contract(OpCode::SET_PROP, None, &[1, 2, 3], false);
         assert_contract(OpCode::SET_PROP_DYNAMIC, None, &[1, 2, 3], false);
+        // SET_PROP_BATCH：b 槽是 Imm(slot) 非寄存器，canonical 构造下仍按槽位读。
+        assert_contract(OpCode::SET_PROP_BATCH, None, &[1, 2, 3], false);
         assert_contract(OpCode::IC_SET_PROP, None, &[1, 2, 3], false);
         assert_contract(OpCode::SET_ELEM, None, &[1, 2, 3], false);
         assert_group(&[OpCode::NEW_OBJECT, OpCode::NEW_ARRAY], Some(1), &[], true);

crates/oxide_ir/src/inst.rs

@@ -247,6 +247,19 @@ impl Inst {
         Self::new(OpCode::SPREAD_OBJECT, target, src, Operand::None)
     }
 
+    /// 对象字面量批量构造：`dst` 为新对象，a 槽编码纯静态数据键前缀的属性数（≤255），
+    /// ext 为每键的常量池下标（`Constant::String`）。运行时按键序链式预建 shape，
+    /// 后续逐个 `SET_PROP_BATCH` 纯槽写。
+    pub fn new_object(dst: Operand, nprops: u32, key_idxs: &[u32]) -> Self {
+        Self::with_ext(OpCode::NEW_OBJECT, dst, Operand::Imm(nprops as u16), Operand::None, key_idxs)
+    }
+
+    /// 对象字面量批量构造的纯槽写：`target[slot] = value`。slot 对应键序预建 shape 的槽位，
+    /// 不做键解析/形状变更。
+    pub fn set_prop_batch(target: Operand, value: Operand, slot: u16) -> Self {
+        Self::new(OpCode::SET_PROP_BATCH, target, value, Operand::Imm(slot))
+    }
+
     /// TEMPLATE_STR：变长 ext。首字打包 `(segment_count<<16) | total_len_hint`，
     /// 后续每 quasi 一项 `quasi_const_idx & 0x7FFF_FFFF`，其后若跟表达式再一项 `0x8000_0000 | expr_reg`。
     pub fn template_str(dst: Operand, segment_count: u32, total_len_hint: u16, parts: &[u32]) -> Self {

crates/oxide_ir/tests/lowering_tests.rs

@@ -307,3 +307,41 @@ fn operand_this_is_semantic_not_physical_index() {
     assert_eq!(Operand::This, Operand::This);
     assert_eq!(Operand::NewTarget, Operand::NewTarget);
 }
+
+#[test]
+fn new_object_batch_carries_nprops_and_key_table() {
+    // NEW_OBJECT(a=Imm(2)) → 2 个键常量 ext 字；键序即 shape 槽序。
+    let mut f = base_module();
+    f.insts.push(Inst::new_object(Operand::Reg(1), 2, &[10, 11]));
+    let m = lower_ok(&f);
+    assert_eq!(m.bytecode.len(), 3);
+    assert_eq!(opcode::opcode(m.bytecode[0]), OpCode::NEW_OBJECT);
+    assert_eq!(opcode::rd(m.bytecode[0]), 1);
+    assert_eq!(opcode::a(m.bytecode[0]), 2, "a 槽编码属性数");
+    assert_eq!(opcode::b(m.bytecode[0]), 0, "nprops ≤255 时高字节为 0");
+    assert_eq!(m.bytecode[1], 10);
+    assert_eq!(m.bytecode[2], 11);
+}
+
+#[test]
+fn new_object_zero_props_has_no_ext_words() {
+    // 空字面量 {} 仍发 0 属性数 NEW_OBJECT，无键表。
+    let mut f = base_module();
+    f.insts.push(Inst::new_object(Operand::Reg(1), 0, &[]));
+    let m = lower_ok(&f);
+    assert_eq!(m.bytecode.len(), 1);
+    assert_eq!(opcode::opcode(m.bytecode[0]), OpCode::NEW_OBJECT);
+    assert_eq!(opcode::a(m.bytecode[0]), 0);
+}
+
+#[test]
+fn set_prop_batch_encodes_slot_imm_in_b() {
+    let mut f = base_module();
+    f.insts.push(Inst::set_prop_batch(Operand::Reg(1), Operand::Reg(2), 3));
+    let m = lower_ok(&f);
+    assert_eq!(m.bytecode.len(), 1);
+    assert_eq!(opcode::opcode(m.bytecode[0]), OpCode::SET_PROP_BATCH);
+    assert_eq!(opcode::rd(m.bytecode[0]), 1);
+    assert_eq!(opcode::a(m.bytecode[0]), 2);
+    assert_eq!(opcode::b(m.bytecode[0]), 3, "slot 编码进 b 槽");
+}