luaur-code-gen 0.1.3

use crate::enums::ir_block_kind::IrBlockKind;
use crate::enums::ir_cmd::IrCmd;
use crate::enums::ir_op_kind::IrOpKind;
use crate::functions::collect_direct_block_jump_path::collect_direct_block_jump_path;
use crate::functions::const_prop_in_block::const_prop_in_block;
use crate::functions::replace_ir_utils::replace_ir_function_ir_op_ir_op;
use crate::functions::setup_block_entry_state_optimize_const_prop::setup_block_entry_state_ir_builder_ir_function_ir_block_const_prop_state;
use crate::macros::op_a::op_a;
use crate::records::const_prop_state::ConstPropState;
use crate::records::ir_block::IrBlock;
use crate::records::ir_builder::IrBuilder;
use crate::records::ir_function::IrFunction;
use alloc::vec::Vec;

pub fn try_create_linear_block(
    build: &mut IrBuilder,
    visited: &mut Vec<u8>,
    starting_block: *mut IrBlock,
    state: &mut ConstPropState,
) {
    let function: *mut IrFunction = &mut build.function;

    unsafe {
        let block_idx = (&*function).get_block_index(&*starting_block);
        crate::macros::codegen_assert::CODEGEN_ASSERT!(visited[block_idx as usize] == 0);
        visited[block_idx as usize] = 1;

        let term_inst_idx = (*starting_block).finish;
        let term_inst = (&mut (*function).instructions)[term_inst_idx as usize].clone();

        if term_inst.cmd != IrCmd::JUMP {
            return;
        }

        let target_op = op_a(&mut term_inst.clone());
        if target_op.kind() != IrOpKind::Block {
            return;
        }

        if (&(*function).blocks)[target_op.index() as usize].use_count == 1 {
            return;
        }

        let target_block_idx = target_op.index();
        let path = collect_direct_block_jump_path(&mut *function, visited, starting_block);

        if (path.len() as i32) < luaur_common::FInt::LuauCodeGenMinLinearBlockPath.get() {
            return;
        }

        state.clear();

        if luaur_common::FFlag::LuauCodegenLinearSetupEntryState3.get() {
            setup_block_entry_state_ir_builder_ir_function_ir_block_const_prop_state(
                build,
                &mut *function,
                &*starting_block,
                state,
            );
        }

        const_prop_in_block(build, &mut *starting_block, state);

        if luaur_common::FFlag::LuauCodegenLinearSetupEntryState3.get() {
            let current_target = {
                let inst = &mut (&mut (*function).instructions)[term_inst_idx as usize].clone();
                op_a(inst).index()
            };

            if (*starting_block).finish != term_inst_idx || current_target != target_block_idx {
                return;
            }

            if (&(*function).blocks)[target_block_idx as usize].use_count == 1 {
                return;
            }
        } else {
            let current_target = {
                let inst =
                    &mut (&mut (*function).instructions)[(*starting_block).finish as usize].clone();
                op_a(inst).index()
            };

            if current_target != target_block_idx {
                crate::macros::codegen_assert::CODEGEN_ASSERT!(false);
                return;
            }
        }

        let starting_sort_key = (*starting_block).sortkey;
        let starting_chain_key = (*starting_block).chainkey;

        let new_block = build.block(IrBlockKind::Linearized);
        visited.push(0);

        build.begin_block(new_block);

        build.function.blocks[new_block.index() as usize].sortkey = starting_sort_key;
        build.function.blocks[new_block.index() as usize].chainkey = starting_chain_key + 1;
        build.function.blocks[block_idx as usize].expected_next_block = new_block.index();

        let op_ptr = {
            let inst = &mut build.function.instructions[term_inst_idx as usize];
            &mut inst.ops.as_mut_slice()[0] as *mut _
        };
        replace_ir_function_ir_op_ir_op(&mut build.function, &mut *op_ptr, new_block);

        build.clone(path.clone(), true);

        if build.function.cfg.r#in.len() == new_block.index() as usize {
            crate::macros::codegen_assert::CODEGEN_ASSERT!(
                build.function.cfg.r#in.len() == build.function.cfg.out.len()
            );
            crate::macros::codegen_assert::CODEGEN_ASSERT!(
                build.function.cfg.r#in.len() == build.function.cfg.def.len()
            );

            build
                .function
                .cfg
                .r#in
                .push(build.function.cfg.r#in[path[0] as usize]);
            build
                .function
                .cfg
                .out
                .push(build.function.cfg.out[*path.last().unwrap() as usize]);
            build.function.cfg.def.push(Default::default());

            let out_vararg_seq = build.function.cfg.out.last().unwrap().vararg_seq;
            let def_idx = build.function.cfg.def.len() - 1;

            for &path_block_idx in &path {
                let path_def = build.function.cfg.def[path_block_idx as usize];
                for i in 0..build.function.cfg.def[def_idx].regs.len() {
                    build.function.cfg.def[def_idx].regs[i] |= path_def.regs[i];
                }

                if path_def.vararg_seq && out_vararg_seq {
                    build.function.cfg.def[def_idx].vararg_seq = true;
                    build.function.cfg.def[def_idx].vararg_start = path_def.vararg_start;
                }
            }

            build
                .function
                .cfg
                .predecessors_offsets
                .push(build.function.cfg.predecessors.len() as u32);
            build.function.cfg.predecessors.push(block_idx);
        }

        let linear_block = &mut build.function.blocks[new_block.index() as usize] as *mut IrBlock;
        const_prop_in_block(build, &mut *linear_block, state);
    }
}