luaur_code_gen/functions/
translate_inst_length.rs

1use crate::enums::ir_cmd::IrCmd;
2use crate::functions::is_userdata_bytecode_type::is_userdata_bytecode_type;
3use crate::records::fallback_stream_scope::FallbackStreamScope;
4use crate::records::ir_builder::IrBuilder;
5use crate::type_aliases::instruction_ir_translation::Instruction;
6use luaur_common::enums::luau_bytecode_type::LuauBytecodeType;
7use luaur_common::macros::luau_insn_a::LUAU_INSN_A;
8use luaur_common::macros::luau_insn_b::LUAU_INSN_B;
9use luaur_vm::enums::lua_type::lua_Type;
10
11pub fn translate_inst_length(build: &mut IrBuilder, pc: *const Instruction, pcpos: i32) {
12    let bc_types = build.function.get_bytecode_types_at(pcpos);
13
14    let ra = LUAU_INSN_A(unsafe { *pc }) as u8;
15    let rb = LUAU_INSN_B(unsafe { *pc }) as u8;
16
17    if is_userdata_bytecode_type(bc_types.a) {
18        let savedpc_arg = build.const_uint((pcpos + 1) as u32);
19        build.inst_ir_cmd_ir_op(IrCmd::SET_SAVEDPC, savedpc_arg);
20        let reg_ra = build.vm_reg(ra);
21        let reg_rb = build.vm_reg(rb);
22        build.inst_ir_cmd_ir_op_ir_op(IrCmd::DO_LEN, reg_ra, reg_rb);
23        return;
24    }
25
26    let fallback = build.fallback_block(pcpos as u32);
27
28    let vm_reg_rb = build.vm_reg(rb);
29    let tb = build.inst_ir_cmd_ir_op(IrCmd::LOAD_TAG, vm_reg_rb);
30    let const_tag_table = build.const_tag(lua_Type::LUA_TTABLE as u8);
31    let exit_or_fallback = if bc_types.a == LuauBytecodeType::LBC_TYPE_TABLE.0 as u8 {
32        build.vm_exit(pcpos as u32)
33    } else {
34        fallback
35    };
36    build.inst_ir_cmd_ir_op_ir_op_ir_op(IrCmd::CHECK_TAG, tb, const_tag_table, exit_or_fallback);
37
38    let vb = build.inst_ir_cmd_ir_op(IrCmd::LOAD_POINTER, vm_reg_rb);
39    build.inst_ir_cmd_ir_op_ir_op(IrCmd::CHECK_NO_METATABLE, vb, fallback);
40
41    let va = build.inst_ir_cmd_ir_op(IrCmd::TABLE_LEN, vb);
42    let vai = build.inst_ir_cmd_ir_op(IrCmd::INT_TO_NUM, va);
43
44    let reg_ra = build.vm_reg(ra);
45    build.inst_ir_cmd_ir_op_ir_op(IrCmd::STORE_DOUBLE, reg_ra, vai);
46    let reg_ra = build.vm_reg(ra);
47    let number_tag = build.const_tag(lua_Type::LUA_TNUMBER as u8);
48    build.inst_ir_cmd_ir_op_ir_op(IrCmd::STORE_TAG, reg_ra, number_tag);
49
50    let next = build.block_at_inst((pcpos + 1) as u32);
51    let mut scope = FallbackStreamScope::new(build, fallback, next);
52    let build = &mut *scope.build;
53
54    let savedpc_arg = build.const_uint((pcpos + 1) as u32);
55    build.inst_ir_cmd_ir_op(IrCmd::SET_SAVEDPC, savedpc_arg);
56    let reg_ra = build.vm_reg(ra);
57    let reg_rb = build.vm_reg(rb);
58    build.inst_ir_cmd_ir_op_ir_op(IrCmd::DO_LEN, reg_ra, reg_rb);
59    build.inst_ir_cmd_ir_op(IrCmd::JUMP, next);
60}
luaur_code_gen/functions/translate_inst_length.rs

luaur_code_gen/functions/
translate_inst_length.rs
