hakorune/src/backend/llvm/compiler/codegen/mod.rs

use super::helpers::{as_float, as_int, map_type};
use super::LLVMCompiler;
use crate::backend::llvm::context::CodegenContext;
use crate::mir::function::MirModule;
use crate::mir::instruction::{ConstValue, MirInstruction, UnaryOp};
use crate::mir::ValueId;
use inkwell::context::Context;
use inkwell::{
    types::{BasicTypeEnum, FloatType, IntType, PointerType},
    values::{BasicValueEnum, FloatValue, FunctionValue, IntValue, PhiValue, PointerValue},
    AddressSpace,
};
use std::collections::HashMap;

// Submodules: helpers for type conversion/classification used by lowering
mod types;
use self::types::{
    classify_tag, cmp_eq_ne_any, i64_to_ptr, map_mirtype_to_basic, to_bool, to_i64_any,
};
mod instructions;

impl LLVMCompiler {
    pub fn new() -> Result<Self, String> {
        Ok(Self {
            values: HashMap::new(),
        })
    }

    pub fn compile_module(&self, mir_module: &MirModule, output_path: &str) -> Result<(), String> {
        if std::env::var("NYASH_CLI_VERBOSE").ok().as_deref() == Some("1") {
            eprintln!(
                "[LLVM] compile_module start: functions={}, out={}",
                mir_module.functions.len(),
                output_path
            );
        }
        let context = Context::create();
        let codegen = CodegenContext::new(&context, "nyash_module")?;
        // Lower only Main.main for now
        // Find entry function
        let func = if let Some((_n, f)) = mir_module
            .functions
            .iter()
            .find(|(_n, f)| f.metadata.is_entry_point)
        {
            f
        } else if let Some(f) = mir_module.functions.get("Main.main") {
            f
        } else if let Some(f) = mir_module.functions.get("main") {
            f
        } else if let Some((_n, f)) = mir_module.functions.iter().next() {
            f
        } else {
            return Err("Main.main function not found in module".to_string());
        };

        // Map MIR types to LLVM types via helpers

        // Load box type-id mapping from nyash_box.toml (central plugin registry)
        let box_type_ids = crate::backend::llvm::box_types::load_box_type_ids();

        // Function type
        let ret_type = match func.signature.return_type {
            crate::mir::MirType::Void => None,
            ref t => Some(map_type(codegen.context, t)?),
        };
        let fn_type = match ret_type {
            Some(BasicTypeEnum::IntType(t)) => t.fn_type(&[], false),
            Some(BasicTypeEnum::FloatType(t)) => t.fn_type(&[], false),
            Some(BasicTypeEnum::PointerType(t)) => t.fn_type(&[], false),
            Some(_) => return Err("Unsupported return basic type".to_string()),
            None => codegen.context.void_type().fn_type(&[], false),
        };
        let llvm_func = codegen.module.add_function("ny_main", fn_type, None);

        // Create LLVM basic blocks: ensure entry is created first to be function entry
        let (mut bb_map, entry_bb) = instructions::create_basic_blocks(&codegen, llvm_func, func);

        // Position at entry
        codegen.builder.position_at_end(entry_bb);

        // SSA value map
        let mut vmap: HashMap<ValueId, BasicValueEnum> = HashMap::new();

        // Helper ops are now provided by codegen/types.rs

        // Pre-create allocas for locals on demand (entry-only builder)
        let mut allocas: HashMap<ValueId, PointerValue> = HashMap::new();
        let entry_builder = codegen.context.create_builder();
        entry_builder.position_at_end(entry_bb);

        // Helper: map MirType to LLVM basic type (value type) is provided by types::map_mirtype_to_basic

        // Helper: create (or get) an alloca for a given pointer-typed SSA value id
        let mut alloca_elem_types: HashMap<ValueId, BasicTypeEnum> = HashMap::new();

        // Pre-create PHI nodes for all blocks (so we can add incoming from predecessors)
        let mut phis_by_block: HashMap<
            crate::mir::BasicBlockId,
            Vec<(ValueId, PhiValue, Vec<(crate::mir::BasicBlockId, ValueId)>)>,
        > = HashMap::new();
        for bid in func.block_ids() {
            let bb = *bb_map.get(&bid).ok_or("missing bb in map")?;
            // Position at start of the block (no instructions emitted yet)
            codegen.builder.position_at_end(bb);
            let block = func.blocks.get(&bid).unwrap();
            for inst in block
                .instructions
                .iter()
                .take_while(|i| matches!(i, MirInstruction::Phi { .. }))
            {
                if let MirInstruction::Phi { dst, inputs } = inst {
                    // Decide PHI type: prefer annotated value type; fallback to first input's annotated type; finally i64
                    let mut phi_ty: Option<BasicTypeEnum> = None;
                    if let Some(mt) = func.metadata.value_types.get(dst) {
                        phi_ty = Some(map_mirtype_to_basic(codegen.context, mt));
                    } else if let Some((_, iv)) = inputs.first() {
                        if let Some(mt) = func.metadata.value_types.get(iv) {
                            phi_ty = Some(map_mirtype_to_basic(codegen.context, mt));
                        }
                    }
                    let phi_ty = phi_ty.unwrap_or_else(|| codegen.context.i64_type().into());
                    let phi = codegen
                        .builder
                        .build_phi(phi_ty, &format!("phi_{}", dst.as_u32()))
                        .map_err(|e| e.to_string())?;
                    vmap.insert(*dst, phi.as_basic_value());
                    phis_by_block
                        .entry(bid)
                        .or_default()
                        .push((*dst, phi, inputs.clone()));
                }
            }
        }

        // Lower in block order
        for bid in func.block_ids() {
            let bb = *bb_map.get(&bid).unwrap();
            if codegen
                .builder
                .get_insert_block()
                .map(|b| b != bb)
                .unwrap_or(true)
            {
                codegen.builder.position_at_end(bb);
            }
            let block = func.blocks.get(&bid).unwrap();
            for inst in &block.instructions {
                match inst {
                    MirInstruction::NewBox {
                        dst,
                        box_type,
                        args,
                    } => {
                        match (box_type.as_str(), args.len()) {
                            ("StringBox", 1) => {
                                // Pass-through: if arg was built as Const String, its lowering produced i8* already
                                let av = *vmap.get(&args[0]).ok_or("StringBox arg missing")?;
                                vmap.insert(*dst, av);
                            }
                            ("IntegerBox", 1) => {
                                // Pass-through integer payload as i64
                                let av = *vmap.get(&args[0]).ok_or("IntegerBox arg missing")?;
                                vmap.insert(*dst, av);
                            }
                            // Minimal birth_i64 path for 1-2 args (i64 or handle-as-i64)
                            (_, n) if n == 1 || n == 2 => {
                                let type_id = *box_type_ids.get(box_type).unwrap_or(&0);
                                let i64t = codegen.context.i64_type();
                                let fnty = i64t.fn_type(
                                    &[i64t.into(), i64t.into(), i64t.into(), i64t.into()],
                                    false,
                                );
                                let callee = codegen
                                    .module
                                    .get_function("nyash.box.birth_i64")
                                    .unwrap_or_else(|| {
                                        codegen.module.add_function(
                                            "nyash.box.birth_i64",
                                            fnty,
                                            None,
                                        )
                                    });
                                // argc
                                let argc = i64t.const_int(args.len() as u64, false);
                                // a1/a2 as i64
                                let mut a1 = i64t.const_zero();
                                let mut a2 = i64t.const_zero();
                                if args.len() >= 1 {
                                    let v = *vmap.get(&args[0]).ok_or("newbox arg[0] missing")?;
                                    a1 = match v {
                                        BasicValueEnum::IntValue(iv) => iv,
                                        BasicValueEnum::PointerValue(pv) => codegen.builder.build_ptr_to_int(pv, i64t, "arg0_p2i").map_err(|e| e.to_string())?,
                                        _ => return Err("newbox arg[0]: unsupported type (expect int or handle ptr)".to_string()),
                                    };
                                }
                                if args.len() >= 2 {
                                    let v = *vmap.get(&args[1]).ok_or("newbox arg[1] missing")?;
                                    a2 = match v {
                                        BasicValueEnum::IntValue(iv) => iv,
                                        BasicValueEnum::PointerValue(pv) => codegen.builder.build_ptr_to_int(pv, i64t, "arg1_p2i").map_err(|e| e.to_string())?,
                                        _ => return Err("newbox arg[1]: unsupported type (expect int or handle ptr)".to_string()),
                                    };
                                }
                                let tid = i64t.const_int(type_id as u64, true);
                                let call = codegen
                                    .builder
                                    .build_call(
                                        callee,
                                        &[tid.into(), argc.into(), a1.into(), a2.into()],
                                        "birth_i64",
                                    )
                                    .map_err(|e| e.to_string())?;
                                let h = call
                                    .try_as_basic_value()
                                    .left()
                                    .ok_or("birth_i64 returned void".to_string())?
                                    .into_int_value();
                                let pty = codegen.context.ptr_type(AddressSpace::from(0));
                                let ptr = codegen
                                    .builder
                                    .build_int_to_ptr(h, pty, "handle_to_ptr")
                                    .map_err(|e| e.to_string())?;
                                vmap.insert(*dst, ptr.into());
                            }
                            _ => {
                                // No-arg birth via central type registry (preferred),
                                // fallback to env.box.new(name) when type_id is unavailable.
                                if !args.is_empty() {
                                    return Err(
                                        "NewBox with >2 args not yet supported in LLVM lowering"
                                            .to_string(),
                                    );
                                }
                                let type_id = *box_type_ids.get(box_type).unwrap_or(&0);
                                // Temporary gate: allow forcing MapBox to plugin path explicitly
                                let force_plugin_map = std::env::var("NYASH_LLVM_FORCE_PLUGIN_MAP")
                                    .ok()
                                    .as_deref()
                                    == Some("1");
                                let i64t = codegen.context.i64_type();
                                if type_id != 0 && !(box_type == "MapBox" && !force_plugin_map) {
                                    // declare i64 @nyash.box.birth_h(i64)
                                    let fn_ty = i64t.fn_type(&[i64t.into()], false);
                                    let callee = codegen
                                        .module
                                        .get_function("nyash.box.birth_h")
                                        .unwrap_or_else(|| {
                                            codegen.module.add_function(
                                                "nyash.box.birth_h",
                                                fn_ty,
                                                None,
                                            )
                                        });
                                    let tid = i64t.const_int(type_id as u64, true);
                                    let call = codegen
                                        .builder
                                        .build_call(callee, &[tid.into()], "birth")
                                        .map_err(|e| e.to_string())?;
                                    let h_i64 = call
                                        .try_as_basic_value()
                                        .left()
                                        .ok_or("birth_h returned void".to_string())?
                                        .into_int_value();
                                    let pty = codegen.context.ptr_type(AddressSpace::from(0));
                                    let ptr = codegen
                                        .builder
                                        .build_int_to_ptr(h_i64, pty, "handle_to_ptr")
                                        .map_err(|e| e.to_string())?;
                                    vmap.insert(*dst, ptr.into());
                                } else {
                                    // Fallback: call i64 @nyash.env.box.new(i8*) with type name
                                    let i8p = codegen.context.ptr_type(AddressSpace::from(0));
                                    let fn_ty = i64t.fn_type(&[i8p.into()], false);
                                    let callee = codegen
                                        .module
                                        .get_function("nyash.env.box.new")
                                        .unwrap_or_else(|| codegen.module.add_function("nyash.env.box.new", fn_ty, None));
                                    let tn = codegen
                                        .builder
                                        .build_global_string_ptr(box_type.as_str(), "box_type_name")
                                        .map_err(|e| e.to_string())?;
                                    let call = codegen
                                        .builder
                                        .build_call(callee, &[tn.as_pointer_value().into()], "env_box_new")
                                        .map_err(|e| e.to_string())?;
                                    let h_i64 = call
                                        .try_as_basic_value()
                                        .left()
                                        .ok_or("env.box.new returned void".to_string())?
                                        .into_int_value();
                                    let pty = codegen.context.ptr_type(AddressSpace::from(0));
                                    let ptr = codegen
                                        .builder
                                        .build_int_to_ptr(h_i64, pty, "handle_to_ptr")
                                        .map_err(|e| e.to_string())?;
                                    vmap.insert(*dst, ptr.into());
                                }
                            }
                        }
                    }
                    MirInstruction::Const { dst, value } => {
                        let bval = match value {
                            ConstValue::Integer(i) => {
                                codegen.context.i64_type().const_int(*i as u64, true).into()
                            }
                            ConstValue::Float(f) => {
                                codegen.context.f64_type().const_float(*f).into()
                            }
                            ConstValue::Bool(b) => codegen
                                .context
                                .bool_type()
                                .const_int(*b as u64, false)
                                .into(),
                            ConstValue::String(s) => {
                                let gv = codegen
                                    .builder
                                    .build_global_string_ptr(s, "str")
                                    .map_err(|e| e.to_string())?;
                                let len =
                                    codegen.context.i32_type().const_int(s.len() as u64, false);
                                // declare i8* @nyash_string_new(i8*, i32)
                                let rt = codegen
                                    .context
                                    .ptr_type(inkwell::AddressSpace::from(0));
                                let fn_ty = rt.fn_type(
                                    &[
                                        codegen
                                            .context
                                            .ptr_type(inkwell::AddressSpace::from(0))
                                            .into(),
                                        codegen.context.i32_type().into(),
                                    ],
                                    false,
                                );
                                let callee = codegen
                                    .module
                                    .get_function("nyash_string_new")
                                    .unwrap_or_else(|| {
                                        codegen.module.add_function("nyash_string_new", fn_ty, None)
                                    });
                                let call = codegen
                                    .builder
                                    .build_call(
                                        callee,
                                        &[gv.as_pointer_value().into(), len.into()],
                                        "strnew",
                                    )
                                    .map_err(|e| e.to_string())?;
                                call.try_as_basic_value()
                                    .left()
                                    .ok_or("nyash_string_new returned void".to_string())?
                            }
                            ConstValue::Null => codegen
                                .context
                                .ptr_type(inkwell::AddressSpace::from(0))
                                .const_zero()
                                .into(),
                            ConstValue::Void => return Err("Const Void unsupported".to_string()),
                        };
                        vmap.insert(*dst, bval);
                    }
                    MirInstruction::BoxCall {
                        dst,
                        box_val,
                        method,
                        method_id,
                        args,
                        effects: _,
                    } => {
                        // Delegate to refactored lowering and skip legacy body
                        instructions::lower_boxcall(
                            &codegen,
                            func,
                            &mut vmap,
                            dst,
                            box_val,
                            method,
                            method_id,
                            args,
                            &box_type_ids,
                            &entry_builder,
                        )?;
                        continue;
                    }
                    MirInstruction::ExternCall { dst, iface_name, method_name, args, effects: _ } => {
                        instructions::lower_externcall(&codegen, func, &mut vmap, dst, iface_name, method_name, args)?;
                    }
                    MirInstruction::UnaryOp { dst, op, operand } => {
                        let v = *vmap.get(operand).ok_or("operand missing")?;
                        let out = match op {
                            UnaryOp::Neg => {
                                if let Some(iv) = as_int(v) {
                                    codegen
                                        .builder
                                        .build_int_neg(iv, "ineg")
                                        .map_err(|e| e.to_string())?
                                        .into()
                                } else if let Some(fv) = as_float(v) {
                                    codegen
                                        .builder
                                        .build_float_neg(fv, "fneg")
                                        .map_err(|e| e.to_string())?
                                        .into()
                                } else {
                                    return Err("neg on non-number".to_string());
                                }
                            }
                            UnaryOp::Not | UnaryOp::BitNot => {
                                if let Some(iv) = as_int(v) {
                                    codegen
                                        .builder
                                        .build_not(iv, "inot")
                                        .map_err(|e| e.to_string())?
                                        .into()
                                } else {
                                    return Err("not on non-int".to_string());
                                }
                            }
                        };
                        vmap.insert(*dst, out);
                    }
                    MirInstruction::BinOp { dst, op, lhs, rhs } => {
                        let lv = *vmap.get(lhs).ok_or("lhs missing")?;
                        let rv = *vmap.get(rhs).ok_or("rhs missing")?;
                        let mut handled_concat = false;
                        // String-like concat handling: if either side is a pointer (i8*),
                        // and op is Add, route to NyRT concat helpers
                        if let crate::mir::BinaryOp::Add = op {
                            let i8p = codegen.context.ptr_type(AddressSpace::from(0));
                            let is_stringish = |vid: &ValueId| -> bool {
                                match func.metadata.value_types.get(vid) {
                                    Some(crate::mir::MirType::String) => true,
                                    Some(crate::mir::MirType::Box(_)) => true,
                                    _ => false,
                                }
                            };
                            match (lv, rv) {
                                (
                                    BasicValueEnum::PointerValue(lp),
                                    BasicValueEnum::PointerValue(rp),
                                ) => {
                                    let fnty = i8p.fn_type(&[i8p.into(), i8p.into()], false);
                                    let callee = codegen
                                        .module
                                        .get_function("nyash.string.concat_ss")
                                        .unwrap_or_else(|| {
                                            codegen.module.add_function(
                                                "nyash.string.concat_ss",
                                                fnty,
                                                None,
                                            )
                                        });
                                    let call = codegen
                                        .builder
                                        .build_call(callee, &[lp.into(), rp.into()], "concat_ss")
                                        .map_err(|e| e.to_string())?;
                                    let rv = call
                                        .try_as_basic_value()
                                        .left()
                                        .ok_or("concat_ss returned void".to_string())?;
                                    vmap.insert(*dst, rv);
                                    handled_concat = true;
                                }
                                (
                                    BasicValueEnum::PointerValue(lp),
                                    BasicValueEnum::IntValue(ri),
                                ) => {
                                    // Minimal fallback: if both sides are annotated String/Box, convert ptr->handle and use concat_hh
                                    if is_stringish(lhs) && is_stringish(rhs) {
                                        let i64t = codegen.context.i64_type();
                                        // from_i8_string: i64(i8*)
                                        let fnty_conv = i64t.fn_type(&[i8p.into()], false);
                                        let conv = codegen
                                            .module
                                            .get_function("nyash.box.from_i8_string")
                                            .unwrap_or_else(|| codegen.module.add_function("nyash.box.from_i8_string", fnty_conv, None));
                                        let call_c = codegen
                                            .builder
                                            .build_call(conv, &[lp.into()], "lhs_i8_to_handle")
                                            .map_err(|e| e.to_string())?;
                                        let lh = call_c
                                            .try_as_basic_value()
                                            .left()
                                            .ok_or("from_i8_string returned void".to_string())?
                                            .into_int_value();
                                        // concat_hh: i64(i64,i64)
                                        let fnty_hh = i64t.fn_type(&[i64t.into(), i64t.into()], false);
                                        let callee = codegen
                                            .module
                                            .get_function("nyash.string.concat_hh")
                                            .unwrap_or_else(|| codegen.module.add_function("nyash.string.concat_hh", fnty_hh, None));
                                        let call = codegen
                                            .builder
                                            .build_call(callee, &[lh.into(), ri.into()], "concat_hh")
                                            .map_err(|e| e.to_string())?;
                                        let rv = call
                                            .try_as_basic_value()
                                            .left()
                                            .ok_or("concat_hh returned void".to_string())?;
                                        vmap.insert(*dst, rv);
                                        handled_concat = true;
                                    } else {
                                        let i64t = codegen.context.i64_type();
                                        let fnty = i8p.fn_type(&[i8p.into(), i64t.into()], false);
                                        let callee = codegen
                                            .module
                                            .get_function("nyash.string.concat_si")
                                            .unwrap_or_else(|| {
                                                codegen.module.add_function(
                                                    "nyash.string.concat_si",
                                                    fnty,
                                                    None,
                                                )
                                            });
                                        let call = codegen
                                            .builder
                                            .build_call(callee, &[lp.into(), ri.into()], "concat_si")
                                            .map_err(|e| e.to_string())?;
                                        let rv = call
                                            .try_as_basic_value()
                                            .left()
                                            .ok_or("concat_si returned void".to_string())?;
                                        vmap.insert(*dst, rv);
                                        handled_concat = true;
                                    }
                                }
                                (
                                    BasicValueEnum::IntValue(li),
                                    BasicValueEnum::PointerValue(rp),
                                ) => {
                                    // Minimal fallback: if both sides are annotated String/Box, convert ptr->handle and use concat_hh
                                    if is_stringish(lhs) && is_stringish(rhs) {
                                        let i64t = codegen.context.i64_type();
                                        let fnty_conv = i64t.fn_type(&[i8p.into()], false);
                                        let conv = codegen
                                            .module
                                            .get_function("nyash.box.from_i8_string")
                                            .unwrap_or_else(|| codegen.module.add_function("nyash.box.from_i8_string", fnty_conv, None));
                                        let call_c = codegen
                                            .builder
                                            .build_call(conv, &[rp.into()], "rhs_i8_to_handle")
                                            .map_err(|e| e.to_string())?;
                                        let rh = call_c
                                            .try_as_basic_value()
                                            .left()
                                            .ok_or("from_i8_string returned void".to_string())?
                                            .into_int_value();
                                        let fnty_hh = i64t.fn_type(&[i64t.into(), i64t.into()], false);
                                        let callee = codegen
                                            .module
                                            .get_function("nyash.string.concat_hh")
                                            .unwrap_or_else(|| codegen.module.add_function("nyash.string.concat_hh", fnty_hh, None));
                                        let call = codegen
                                            .builder
                                            .build_call(callee, &[li.into(), rh.into()], "concat_hh")
                                            .map_err(|e| e.to_string())?;
                                        let rv = call
                                            .try_as_basic_value()
                                            .left()
                                            .ok_or("concat_hh returned void".to_string())?;
                                        vmap.insert(*dst, rv);
                                        handled_concat = true;
                                    } else {
                                        let i64t = codegen.context.i64_type();
                                        let fnty = i8p.fn_type(&[i64t.into(), i8p.into()], false);
                                        let callee = codegen
                                            .module
                                            .get_function("nyash.string.concat_is")
                                            .unwrap_or_else(|| {
                                                codegen.module.add_function(
                                                    "nyash.string.concat_is",
                                                    fnty,
                                                    None,
                                                )
                                            });
                                        let call = codegen
                                            .builder
                                            .build_call(callee, &[li.into(), rp.into()], "concat_is")
                                            .map_err(|e| e.to_string())?;
                                        let rv = call
                                            .try_as_basic_value()
                                            .left()
                                            .ok_or("concat_is returned void".to_string())?;
                                        vmap.insert(*dst, rv);
                                        handled_concat = true;
                                    }
                                }
                                _ => {}
                            }
                        }
                        if handled_concat {
                            // Concat already lowered and dst set
                        } else {
                            let out = if let (Some(li), Some(ri)) = (as_int(lv), as_int(rv)) {
                                use crate::mir::BinaryOp as B;
                                match op {
                                    B::Add => codegen
                                        .builder
                                        .build_int_add(li, ri, "iadd")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::Sub => codegen
                                        .builder
                                        .build_int_sub(li, ri, "isub")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::Mul => codegen
                                        .builder
                                        .build_int_mul(li, ri, "imul")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::Div => codegen
                                        .builder
                                        .build_int_signed_div(li, ri, "idiv")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::Mod => codegen
                                        .builder
                                        .build_int_signed_rem(li, ri, "imod")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::BitAnd => codegen
                                        .builder
                                        .build_and(li, ri, "iand")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::BitOr => codegen
                                        .builder
                                        .build_or(li, ri, "ior")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::BitXor => codegen
                                        .builder
                                        .build_xor(li, ri, "ixor")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::Shl => codegen
                                        .builder
                                        .build_left_shift(li, ri, "ishl")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::Shr => codegen
                                        .builder
                                        .build_right_shift(li, ri, false, "ishr")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::And | B::Or => {
                                        // Treat as logical on integers: convert to i1 and and/or
                                        let lb =
                                            to_bool(codegen.context, li.into(), &codegen.builder)?;
                                        let rb =
                                            to_bool(codegen.context, ri.into(), &codegen.builder)?;
                                        match op {
                                            B::And => codegen
                                                .builder
                                                .build_and(lb, rb, "land")
                                                .map_err(|e| e.to_string())?
                                                .into(),
                                            _ => codegen
                                                .builder
                                                .build_or(lb, rb, "lor")
                                                .map_err(|e| e.to_string())?
                                                .into(),
                                        }
                                    }
                                }
                            } else if let (Some(lf), Some(rf)) = (as_float(lv), as_float(rv)) {
                                use crate::mir::BinaryOp as B;
                                match op {
                                    B::Add => codegen
                                        .builder
                                        .build_float_add(lf, rf, "fadd")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::Sub => codegen
                                        .builder
                                        .build_float_sub(lf, rf, "fsub")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::Mul => codegen
                                        .builder
                                        .build_float_mul(lf, rf, "fmul")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::Div => codegen
                                        .builder
                                        .build_float_div(lf, rf, "fdiv")
                                        .map_err(|e| e.to_string())?
                                        .into(),
                                    B::Mod => return Err("fmod not supported yet".to_string()),
                                    _ => return Err("bit/logic ops on float".to_string()),
                                }
                            } else {
                                return Err("binop type mismatch".to_string());
                            };
                            vmap.insert(*dst, out);
                        }
                    }
                    MirInstruction::Compare { dst, op, lhs, rhs } => {
                        let out = instructions::lower_compare(&codegen, &vmap, op, lhs, rhs)?;
                        vmap.insert(*dst, out);
                    }
                    MirInstruction::Store { value, ptr } => {
                        instructions::lower_store(&codegen, &vmap, &mut allocas, &mut alloca_elem_types, value, ptr)?;
                    }
                    MirInstruction::Load { dst, ptr } => {
                        instructions::lower_load(&codegen, &mut vmap, &mut allocas, &mut alloca_elem_types, dst, ptr)?;
                    }
                    MirInstruction::Phi { .. } => {
                        // Already created in pre-pass; nothing to do here.
                    }
                    _ => { /* ignore other ops for 11.1 */ }
                }
            }
            if let Some(term) = &block.terminator {
                match term {
                    MirInstruction::Return { value } => {
                        instructions::emit_return(&codegen, func, &vmap, value)?;
                    }
                    MirInstruction::Jump { target } => {
                        instructions::emit_jump(&codegen, bid, target, &bb_map, &phis_by_block, &vmap)?;
                    }
                    MirInstruction::Branch { condition, then_bb, else_bb } => {
                        instructions::emit_branch(&codegen, bid, condition, then_bb, else_bb, &bb_map, &phis_by_block, &vmap)?;
                    }
                    _ => {}
                }
            }
        }

        // Verify and emit
        if !llvm_func.verify(true) {
            return Err("Function verification failed".to_string());
        }
        // Try writing via file API first; if it succeeds but file is missing due to env/FS quirks,
        // also write via memory buffer as a fallback to ensure presence.
        let verbose = std::env::var("NYASH_CLI_VERBOSE").ok().as_deref() == Some("1");
        if verbose {
            eprintln!("[LLVM] emitting object to {} (begin)", output_path);
        }
        match codegen.target_machine.write_to_file(
            &codegen.module,
            inkwell::targets::FileType::Object,
            std::path::Path::new(output_path),
        ) {
            Ok(_) => {
                // Verify; if missing, fallback to memory buffer write
                if std::fs::metadata(output_path).is_err() {
                    let buf = codegen
                        .target_machine
                        .write_to_memory_buffer(&codegen.module, inkwell::targets::FileType::Object)
                        .map_err(|e| format!("Failed to get object buffer: {}", e))?;
                    std::fs::write(output_path, buf.as_slice()).map_err(|e| {
                        format!("Failed to write object to '{}': {}", output_path, e)
                    })?;
                    if verbose {
                        eprintln!(
                            "[LLVM] wrote object via memory buffer fallback: {} ({} bytes)",
                            output_path,
                            buf.get_size()
                        );
                    }
                } else if verbose {
                    if let Ok(meta) = std::fs::metadata(output_path) {
                        eprintln!(
                            "[LLVM] wrote object via file API: {} ({} bytes)",
                            output_path,
                            meta.len()
                        );
                    }
                }
                if verbose {
                    eprintln!("[LLVM] emit complete (Ok branch) for {}", output_path);
                }
                Ok(())
            }
            Err(e) => {
                // Fallback: memory buffer
                let buf = codegen
                    .target_machine
                    .write_to_memory_buffer(&codegen.module, inkwell::targets::FileType::Object)
                    .map_err(|ee| {
                        format!(
                            "Failed to write object ({}); and memory buffer failed: {}",
                            e, ee
                        )
                    })?;
                std::fs::write(output_path, buf.as_slice()).map_err(|ee| {
                    format!(
                        "Failed to write object to '{}': {} (original error: {})",
                        output_path, ee, e
                    )
                })?;
                if verbose {
                    eprintln!(
                        "[LLVM] wrote object via error fallback: {} ({} bytes)",
                        output_path,
                        buf.get_size()
                    );
                }
                if verbose {
                    eprintln!(
                        "[LLVM] emit complete (Err branch handled) for {}",
                        output_path
                    );
                }
                Ok(())
            }
        }
    }
}
#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_compiler_creation() {
        let compiler = LLVMCompiler::new();
        assert!(compiler.is_ok());
    }
}