ir

src/ir/inst.zig

@@ -0,0 +1,436 @@
+const std = @import("std");
+const types = @import("types.zig");
+const TypeId = types.TypeId;
+const StringId = types.StringId;
+
+// ── Handles ─────────────────────────────────────────────────────────────
+
+/// Reference to an SSA value (instruction result).
+pub const Ref = enum(u32) {
+    /// Sentinel for "no value" / unused operand.
+    none = std.math.maxInt(u32),
+    _,
+
+    pub fn index(self: Ref) u32 {
+        return @intFromEnum(self);
+    }
+
+    pub fn fromIndex(i: u32) Ref {
+        return @enumFromInt(i);
+    }
+
+    pub fn isNone(self: Ref) bool {
+        return self == .none;
+    }
+};
+
+pub const BlockId = enum(u32) {
+    _,
+
+    pub fn index(self: BlockId) u32 {
+        return @intFromEnum(self);
+    }
+
+    pub fn fromIndex(i: u32) BlockId {
+        return @enumFromInt(i);
+    }
+};
+
+pub const FuncId = enum(u32) {
+    _,
+
+    pub fn index(self: FuncId) u32 {
+        return @intFromEnum(self);
+    }
+
+    pub fn fromIndex(i: u32) FuncId {
+        return @enumFromInt(i);
+    }
+};
+
+pub const GlobalId = enum(u32) {
+    _,
+
+    pub fn index(self: GlobalId) u32 {
+        return @intFromEnum(self);
+    }
+
+    pub fn fromIndex(i: u32) GlobalId {
+        return @enumFromInt(i);
+    }
+};
+
+// ── Span ────────────────────────────────────────────────────────────────
+
+pub const Span = struct {
+    start: u32 = 0,
+    end: u32 = 0,
+};
+
+// ── Instruction ─────────────────────────────────────────────────────────
+
+pub const Inst = struct {
+    op: Op,
+    ty: TypeId,
+    span: Span = .{},
+};
+
+// ── Op (tagged union) ───────────────────────────────────────────────────
+
+pub const Op = union(enum) {
+    // ── Constants ───────────────────────────────────────────────────
+    const_int: i64,
+    const_float: f64,
+    const_bool: bool,
+    const_string: StringId,
+    const_null,
+    const_undef, // `---` undefined initializer
+
+    // ── Arithmetic ──────────────────────────────────────────────────
+    add: BinOp,
+    sub: BinOp,
+    mul: BinOp,
+    div: BinOp,
+    mod: BinOp,
+    neg: UnaryOp, // unary -x
+
+    // ── Bitwise ─────────────────────────────────────────────────────
+    bit_and: BinOp,
+    bit_or: BinOp,
+    bit_xor: BinOp,
+    bit_not: UnaryOp,
+    shl: BinOp,
+    shr: BinOp,
+
+    // ── Comparison ──────────────────────────────────────────────────
+    cmp_eq: BinOp,
+    cmp_ne: BinOp,
+    cmp_lt: BinOp,
+    cmp_le: BinOp,
+    cmp_gt: BinOp,
+    cmp_ge: BinOp,
+
+    // ── Logical ─────────────────────────────────────────────────────
+    bool_and: BinOp, // short-circuit &&
+    bool_or: BinOp, // short-circuit ||
+    bool_not: UnaryOp,
+
+    // ── Conversions ─────────────────────────────────────────────────
+    widen: Conversion, // safe widening (s32 → s64)
+    narrow: Conversion, // truncation via `xx` (s64 → s32)
+    bitcast: Conversion, // reinterpret bits
+    int_to_float: Conversion,
+    float_to_int: Conversion,
+
+    // ── Memory ──────────────────────────────────────────────────────
+    alloca: TypeId, // stack allocation, result is *T
+    load: UnaryOp, // load from pointer
+    store: Store, // store value to pointer
+    heap_alloc: UnaryOp, // context.allocator.alloc(size) → *void
+    heap_free: UnaryOp, // context.allocator.free(ptr)
+
+    // ── Struct ops ──────────────────────────────────────────────────
+    struct_init: Aggregate, // construct struct from field values
+    struct_get: FieldAccess, // read struct field by index
+    struct_gep: FieldAccess, // get pointer to struct field (GEP)
+
+    // ── Enum ops ────────────────────────────────────────────────────
+    enum_init: EnumInit, // construct enum value (tag + optional payload)
+    enum_tag: UnaryOp, // extract tag from enum/union
+    enum_payload: FieldAccess, // extract payload from tagged union
+
+    // ── Union ops ───────────────────────────────────────────────────
+    union_get: FieldAccess, // read union field (reinterpret)
+    union_gep: FieldAccess, // pointer to union field
+
+    // ── Array/Slice ops ─────────────────────────────────────────────
+    index_get: BinOp, // arr[idx] → value
+    index_gep: BinOp, // &arr[idx] → pointer
+    length: UnaryOp, // .len on slice/string/array
+    data_ptr: UnaryOp, // .ptr on slice/string
+    subslice: Subslice, // arr[lo..hi]
+    array_to_slice: UnaryOp, // [N]T → []T
+
+    // ── Tuple ops ───────────────────────────────────────────────────
+    tuple_init: Aggregate, // construct tuple from values
+    tuple_get: FieldAccess, // read tuple element by index
+
+    // ── Optional ops ────────────────────────────────────────────────
+    optional_wrap: UnaryOp, // T → ?T
+    optional_unwrap: UnaryOp, // ?T → T (UB if null)
+    optional_has_value: UnaryOp, // ?T → bool
+    optional_coalesce: BinOp, // a ?? b
+
+    // ── Pointer ops ─────────────────────────────────────────────────
+    addr_of: UnaryOp, // @x → *T
+    deref: UnaryOp, // p.* → T
+
+    // ── Vector ops ──────────────────────────────────────────────────
+    vec_splat: UnaryOp, // scalar → vector (broadcast)
+    vec_extract: BinOp, // vec[idx] → scalar
+    vec_insert: TriOp, // vec, idx, val → new_vec
+
+    // ── Calls ───────────────────────────────────────────────────────
+    call: Call,
+    call_indirect: CallIndirect,
+    call_closure: CallIndirect,
+    call_builtin: BuiltinCall,
+
+    // ── Protocol dispatch ───────────────────────────────────────────
+    protocol_call_dynamic: ProtocolCall, // vtable/inline dispatch
+    protocol_erase: ProtocolErase, // concrete → protocol value (xx)
+
+    // ── Closure creation ────────────────────────────────────────────
+    closure_create: ClosureCreate,
+
+    // ── Context ─────────────────────────────────────────────────────
+    context_load: ContextOp, // read context field
+    context_store: ContextOp, // write context field
+    context_save, // save context state (for push)
+    context_restore: UnaryOp, // restore context state (after push)
+
+    // ── Globals ─────────────────────────────────────────────────────
+    global_get: GlobalId,
+    global_set: GlobalSet,
+
+    // ── Block params (SSA phi alternative) ──────────────────────────
+    block_param: BlockParam,
+
+    // ── Any type ────────────────────────────────────────────────────
+    box_any: BoxAny, // T → Any (erase type)
+    unbox_any: UnaryOp, // Any → T (restore type)
+
+    // ── Terminators ─────────────────────────────────────────────────
+    br: Branch,
+    cond_br: CondBranch,
+    switch_br: SwitchBranch,
+    ret: UnaryOp,
+    ret_void,
+    @"unreachable",
+
+    // ── Misc ────────────────────────────────────────────────────────
+    /// No-op placeholder for unlowered AST nodes.
+    placeholder: StringId, // name of the unlowered construct
+};
+
+// ── Operand structs ─────────────────────────────────────────────────────
+
+pub const UnaryOp = struct {
+    operand: Ref,
+};
+
+pub const BinOp = struct {
+    lhs: Ref,
+    rhs: Ref,
+};
+
+pub const TriOp = struct {
+    a: Ref,
+    b: Ref,
+    c: Ref,
+};
+
+pub const Store = struct {
+    ptr: Ref,
+    val: Ref,
+};
+
+pub const Conversion = struct {
+    operand: Ref,
+    from: TypeId,
+    to: TypeId,
+};
+
+pub const FieldAccess = struct {
+    base: Ref,
+    field_index: u32,
+};
+
+pub const Aggregate = struct {
+    fields: []const Ref,
+};
+
+pub const EnumInit = struct {
+    tag: u32,
+    payload: Ref, // Ref.none if no payload
+};
+
+pub const Subslice = struct {
+    base: Ref,
+    lo: Ref,
+    hi: Ref,
+};
+
+pub const Call = struct {
+    callee: FuncId,
+    args: []const Ref,
+};
+
+pub const CallIndirect = struct {
+    callee: Ref,
+    args: []const Ref,
+};
+
+pub const BuiltinCall = struct {
+    builtin: BuiltinId,
+    args: []const Ref,
+};
+
+pub const BuiltinId = enum(u16) {
+    print,
+    out,
+    sqrt,
+    size_of,
+    cast,
+    malloc,
+    free,
+    memcpy,
+    memset,
+};
+
+pub const ProtocolCall = struct {
+    receiver: Ref, // protocol value (ctx + vtable/fn_ptrs)
+    method_index: u32,
+    args: []const Ref,
+};
+
+pub const ProtocolErase = struct {
+    concrete: Ref,
+    protocol_type: TypeId,
+};
+
+pub const ClosureCreate = struct {
+    func: FuncId, // trampoline function
+    env: Ref, // allocated env pointer (or Ref.none for no captures)
+};
+
+pub const ContextOp = struct {
+    field: StringId,
+    value: Ref, // Ref.none for loads
+};
+
+pub const GlobalSet = struct {
+    global: GlobalId,
+    value: Ref,
+};
+
+pub const BlockParam = struct {
+    block: BlockId,
+    param_index: u32,
+};
+
+pub const BoxAny = struct {
+    operand: Ref,
+    source_type: TypeId,
+};
+
+pub const Branch = struct {
+    target: BlockId,
+    args: []const Ref, // block param values
+};
+
+pub const CondBranch = struct {
+    cond: Ref,
+    then_target: BlockId,
+    then_args: []const Ref,
+    else_target: BlockId,
+    else_args: []const Ref,
+};
+
+pub const SwitchBranch = struct {
+    operand: Ref,
+    cases: []const Case,
+    default: BlockId,
+    default_args: []const Ref,
+
+    pub const Case = struct {
+        value: i64,
+        target: BlockId,
+        args: []const Ref,
+    };
+};
+
+// ── Block ───────────────────────────────────────────────────────────────
+
+pub const Block = struct {
+    name: StringId,
+    params: []const TypeId, // block parameter types (SSA phi alternative)
+    insts: std.ArrayList(Inst),
+
+    pub fn init(name: StringId, params: []const TypeId) Block {
+        return .{
+            .name = name,
+            .params = params,
+            .insts = std.ArrayList(Inst).empty,
+        };
+    }
+
+    pub fn deinit(self: *Block, alloc: std.mem.Allocator) void {
+        self.insts.deinit(alloc);
+    }
+};
+
+// ── Function ────────────────────────────────────────────────────────────
+
+pub const Function = struct {
+    name: StringId,
+    params: []const Param,
+    ret: TypeId,
+    blocks: std.ArrayList(Block),
+    is_extern: bool = false,
+    is_comptime: bool = false,
+    linkage: Linkage = .internal,
+
+    pub const Param = struct {
+        name: StringId,
+        ty: TypeId,
+    };
+
+    pub const Linkage = enum {
+        internal,
+        external,
+        private,
+    };
+
+    pub fn init(name: StringId, params: []const Param, ret: TypeId) Function {
+        return .{
+            .name = name,
+            .params = params,
+            .ret = ret,
+            .blocks = std.ArrayList(Block).empty,
+        };
+    }
+
+    pub fn deinit(self: *Function, alloc: std.mem.Allocator) void {
+        for (self.blocks.items) |*block| {
+            block.deinit(alloc);
+        }
+        self.blocks.deinit(alloc);
+    }
+};
+
+// ── Global ──────────────────────────────────────────────────────────────
+
+pub const Global = struct {
+    name: StringId,
+    ty: TypeId,
+    init_val: ?ConstantValue = null,
+    is_extern: bool = false,
+    is_const: bool = false,
+    /// For comptime globals: the function to interpret to get the init value.
+    comptime_func: ?FuncId = null,
+};
+
+// ── ConstantValue ───────────────────────────────────────────────────────
+
+pub const ConstantValue = union(enum) {
+    int: i64,
+    float: f64,
+    boolean: bool,
+    string: StringId,
+    null_val,
+    undef,
+    zeroinit,
+    aggregate: []const ConstantValue,
+};
+