args.c

#include "moar.h"

MVM_STATIC_INLINE MVMint32 is_named_used(MVMArgProcContext *ctx, MVMuint32 idx) {
    return ctx->named_used_size > 64
        ? ctx->named_used.byte_array[idx]
        : ctx->named_used.bit_field & ((MVMuint64)1 << idx);
}

MVM_STATIC_INLINE void mark_named_used(MVMArgProcContext *ctx, MVMuint32 idx) {
    if (ctx->named_used_size > 64)
        ctx->named_used.byte_array[idx] = 1;
    else
        ctx->named_used.bit_field |= (MVMuint64)1 << idx;
}

/* An identity map is just an array { 0, 1, 2, ... }. */
static MVMuint16 * create_identity_map(MVMThreadContext *tc, MVMuint32 size) {
    MVMuint16 *map = MVM_fixed_size_alloc(tc, tc->instance->fsa,
            size * sizeof(MVMuint16));
    MVMuint32 i;
    for (i = 0; i < size; i++)
        map[i] = i;
    return map;
}

/* Set up an initial identity map, big enough assuming nobody passes a
 * really large number of arguments. */
void MVM_args_setup_identity_map(MVMThreadContext *tc) {
    tc->instance->identity_arg_map_alloc = MVM_ARGS_SMALL_IDENTITY_MAP_SIZE;
    tc->instance->identity_arg_map = create_identity_map(tc,
            tc->instance->identity_arg_map_alloc);
    tc->instance->small_identity_arg_map = tc->instance->identity_arg_map;
}

/* Free memory associated with the identity map(s). */
void MVM_args_destroy_identity_map(MVMThreadContext *tc) {
    MVM_fixed_size_free(tc, tc->instance->fsa,
            tc->instance->identity_arg_map_alloc * sizeof(MVMuint16),
            tc->instance->identity_arg_map);
    if (tc->instance->identity_arg_map != tc->instance->small_identity_arg_map)
        MVM_fixed_size_free(tc, tc->instance->fsa,
                MVM_ARGS_SMALL_IDENTITY_MAP_SIZE * sizeof(MVMuint16),
                tc->instance->small_identity_arg_map);
}

/* Perform flattening of arguments as provided, and return the resulting
 * callstack record. */
static MVMint32 callsite_name_index(MVMThreadContext *tc, MVMCallStackFlattening *record,
        MVMuint16 names_so_far, MVMString *search_name) {
    MVMCallsite *cs = &(record->produced_cs);
    MVMuint16 i;
    for (i = 0; i < names_so_far; i++)
        if (MVM_string_equal(tc, cs->arg_names[i], search_name))
            return cs->num_pos + i;
    return -1;
}
MVMCallStackFlattening * MVM_args_perform_flattening(MVMThreadContext *tc, MVMCallsite *cs,
        MVMRegister *source, MVMuint16 *map) {
    /* Go through the callsite and find the flattening things, counting up the
     * number of arguments it will provide and validating that we know how to
     * flatten the passed object. We also save the flatten counts, just in case,
     * so we do not end up doing a buffer overrun if the source gets mutated in
     * the meantime. */
    MVMuint32 num_pos = 0;
    MVMuint32 num_args = 0;
    MVMuint16 i;
    MVMuint16 *flatten_counts = alloca(cs->flag_count * sizeof(MVMuint16));
    for (i = 0; i < cs->flag_count; i++) {
        MVMCallsiteFlags flag = cs->arg_flags[i];
        if (flag & MVM_CALLSITE_ARG_FLAT) {
            /* Positional flattening. */
            MVMObject *list = source[map[i]].o;
            MVMuint32 repr = REPR(list)->ID;
            if ((repr != MVM_REPR_ID_VMArray && repr != MVM_REPR_ID_MultiDimArray)
                    || !IS_CONCRETE(list))
                MVM_exception_throw_adhoc(tc,
                        "Argument flattening array must be a concrete VMArray or MultiDimArray");
            MVMint64 elems = REPR(list)->elems(tc, STABLE(list), list, OBJECT_BODY(list));
            if (elems > MVM_ARGS_LIMIT)
                MVM_exception_throw_adhoc(tc,
                        "Flattened array has %"PRId64" elements, but argument lists are limited to %"PRId32"",
                        elems, MVM_ARGS_LIMIT);
            flatten_counts[i] = (MVMuint16)elems;
            num_pos += (MVMuint16)elems;
            num_args += (MVMuint16)elems;
        }
        else if (flag & MVM_CALLSITE_ARG_FLAT_NAMED) {
            /* Named flattening. */
            MVMObject *hash = source[map[i]].o;
            if (REPR(hash)->ID != MVM_REPR_ID_MVMHash || !IS_CONCRETE(hash))
                MVM_exception_throw_adhoc(tc,
                        "Argument flattening hash must be a concrete VMHash");
            MVMint64 elems = REPR(hash)->elems(tc, STABLE(hash), hash, OBJECT_BODY(hash));
            if (elems > MVM_ARGS_LIMIT)
                MVM_exception_throw_adhoc(tc,
                        "Flattened hash has %"PRId64" elements, but argument lists are limited to %"PRId32"",
                        elems, MVM_ARGS_LIMIT);
            flatten_counts[i] = (MVMuint16)elems;
            num_args += (MVMuint16)elems;
        }
        else if (flag & MVM_CALLSITE_ARG_NAMED) {
            /* Named arg. */
            num_args++;
        }
        else {
            /* Positional arg. */
            num_pos++;
            num_args++;
        }
    }

    /* Ensure we're in range. */
    if (num_args > MVM_ARGS_LIMIT)
        MVM_exception_throw_adhoc(tc,
                "Flattening produced %"PRId32" values, but argument lists are limited to %"PRId32"",
                num_args, MVM_ARGS_LIMIT);

    /* Now populate the flattening record with the arguments. */
    MVMCallStackFlattening *record = MVM_callstack_allocate_flattening(tc, num_args, num_pos);
    MVMuint16 cur_orig_name = 0;
    MVMuint16 cur_new_arg = 0;
    MVMuint16 cur_new_name = 0;
    for (i = 0; i < cs->flag_count; i++) {
        MVMCallsiteFlags flag = cs->arg_flags[i];
        if (flag & MVM_CALLSITE_ARG_FLAT) {
            /* Positional flattening. */
            if (flatten_counts[i] == 0)
                continue;
            MVMuint16 j;
            MVMObject *list = source[map[i]].o;
            MVMStorageSpec lss = REPR(list)->pos_funcs.get_elem_storage_spec(tc, STABLE(list));
            for (j = 0; j < flatten_counts[i]; j++) {
                switch (lss.inlineable ? lss.boxed_primitive : 0) {
                    case MVM_STORAGE_SPEC_BP_INT:
                        record->produced_cs.arg_flags[cur_new_arg] = MVM_CALLSITE_ARG_INT;
                        record->arg_info.source[cur_new_arg].i64 = MVM_repr_at_pos_i(tc, list, j);
                        break;
                    case MVM_STORAGE_SPEC_BP_NUM:
                        record->produced_cs.arg_flags[cur_new_arg] = MVM_CALLSITE_ARG_NUM;
                        record->arg_info.source[cur_new_arg].n64 = MVM_repr_at_pos_n(tc, list, j);
                        break;
                    case MVM_STORAGE_SPEC_BP_STR:
                        record->produced_cs.arg_flags[cur_new_arg] = MVM_CALLSITE_ARG_STR;
                        record->arg_info.source[cur_new_arg].s = MVM_repr_at_pos_s(tc, list, j);
                        break;
                    default:
                        record->produced_cs.arg_flags[cur_new_arg] = MVM_CALLSITE_ARG_OBJ;
                        record->arg_info.source[cur_new_arg].o = MVM_repr_at_pos_o(tc, list, j);
                        break;
                }
                cur_new_arg++;
            }
        }
        else if (flag & MVM_CALLSITE_ARG_FLAT_NAMED) {
            /* Named flattening. */
            if (flatten_counts[i] == 0)
                continue;
            MVMObject *hash = source[map[i]].o;
            MVMHashBody *body = &((MVMHash *)hash)->body;
            MVMStrHashTable *hashtable = &(body->hashtable);
            MVMStrHashIterator iterator = MVM_str_hash_first(tc, hashtable);
            MVMuint32 limit = flatten_counts[i];
            MVMuint32 j = 0;
            while (!MVM_str_hash_at_end(tc, hashtable, iterator)) {
                if (j++ < limit) { /* Drop silently, we don't want to throw here. */
                    MVMHashEntry *current = MVM_str_hash_current_nocheck(tc, hashtable, iterator);
                    MVMString *arg_name = current->hash_handle.key;
                    MVMint32 already_index = callsite_name_index(tc, record, cur_new_name,
                            arg_name);
                    if (already_index < 0) {
                        /* Didn't see this name yet, so add to callsite and args. */
                        record->produced_cs.arg_flags[cur_new_arg] =
                                MVM_CALLSITE_ARG_NAMED | MVM_CALLSITE_ARG_OBJ;
                        record->arg_info.source[cur_new_arg].o = current->value;
                        cur_new_arg++;
                        record->produced_cs.arg_names[cur_new_name] = arg_name;
                        cur_new_name++;
                    }
                    else {
                        /* New value for an existing name; replace the value and
                         * ensure correct type flag. */
                        record->produced_cs.arg_flags[already_index] =
                                MVM_CALLSITE_ARG_NAMED | MVM_CALLSITE_ARG_OBJ;
                        record->arg_info.source[already_index].o = current->value;
                    }
                }
                iterator = MVM_str_hash_next(tc, hashtable, iterator);
            }
        }
        else if (flag & MVM_CALLSITE_ARG_NAMED) {
            /* Named arg. */
            MVMint32 already_index = callsite_name_index(tc, record, cur_new_name,
                    cs->arg_names[cur_orig_name]);
            if (already_index < 0) {
                /* New name, so add to new callsite and args. */
                record->produced_cs.arg_flags[cur_new_arg] = cs->arg_flags[i];
                record->arg_info.source[cur_new_arg] = source[map[i]];
                cur_new_arg++;
                record->produced_cs.arg_names[cur_new_name] = cs->arg_names[cur_orig_name];
                cur_new_name++;
            }
            else {
                /* New value for an existing name; replace the value and
                 * ensure correct type flag. */
                record->produced_cs.arg_flags[already_index] = cs->arg_flags[i];
                record->arg_info.source[already_index] = source[map[i]];
            }
            cur_orig_name++;
        }
        else {
            /* Positional arg. */
            record->produced_cs.arg_flags[cur_new_arg] = cs->arg_flags[i];
            record->arg_info.source[cur_new_arg] = source[map[i]];
            cur_new_arg++;
        }
    }

    /* Fix up the callsite if we didn't get as many args as expected (which
     * can happen if we de-dupe named arguments). */
    if (cur_new_arg != num_args) {
        record->arg_info.callsite->flag_count = cur_new_arg;
    }

    /* See if we can intern it, but don't force that to happen at this point.
     * It should *not* steal this callsite, because it's "stack" allocated;
     * if it makes an intern of it, then it should copy it. */
    MVM_callsite_intern(tc, &(record->arg_info.callsite), 0, 0);

    return record;
}

/* Grows the identity map to a full size one if we overflow the small one. */
void MVM_args_grow_identity_map(MVMThreadContext *tc, MVMCallsite *callsite) {
    uv_mutex_lock(&tc->instance->mutex_callsite_interns);
    assert(callsite->flag_count <= MVM_ARGS_LIMIT);
    MVMuint32 full_size = MVM_ARGS_LIMIT + 1;
    if (tc->instance->identity_arg_map_alloc != full_size) { // Double-check under lock
        tc->instance->identity_arg_map = create_identity_map(tc, full_size);
        MVM_barrier();
        tc->instance->identity_arg_map_alloc = full_size;
    }
    uv_mutex_unlock(&tc->instance->mutex_callsite_interns);
}

/* Marks a named used in the current callframe. */
void MVM_args_marked_named_used(MVMThreadContext *tc, MVMuint32 idx) {
    mark_named_used(&(tc->cur_frame->params), idx);
}

/* Make a copy of the callsite. */
MVMCallsite * MVM_args_copy_callsite(MVMThreadContext *tc, MVMArgProcContext *ctx) {
    return MVM_callsite_copy(tc, ctx->arg_info.callsite);
}

MVMObject * MVM_args_use_capture(MVMThreadContext *tc, MVMFrame *f) {
    /* We used to try and avoid some GC churn by keeping one call capture per
     * thread that was mutated. However, its lifetime was difficult to manage,
     * leading to leaks and subtle bugs. So, we use save_capture always now
     * for this; we may later eliminate it using escape analysis, or treat
     * it differently in the optimizer. */
    return MVM_args_save_capture(tc, f);
}

MVMObject * MVM_args_save_capture(MVMThreadContext *tc, MVMFrame *frame) {
    return MVM_capture_from_args(tc, frame->params.arg_info);
}

/* Checks that the passed arguments fall within the expected arity. */
static void arity_fail(MVMThreadContext *tc, MVMuint16 got, MVMuint16 min, MVMuint16 max) {
    char *problem = got > max ? "Too many" : "Too few";
    if (min == max)
        MVM_exception_throw_adhoc(tc, "%s positionals passed; expected %d argument%s but got %d",
            problem, min, (min == 1 ? "" : "s"), got);
    else if (max == MVM_ARGS_LIMIT)
        MVM_exception_throw_adhoc(tc, "%s positionals passed; expected at least %d arguments but got only %d",
            problem, min, got);
    else
        MVM_exception_throw_adhoc(tc, "%s positionals passed; expected %d %s %d arguments but got %d",
            problem, min, (min + 1 == max ? "or" : "to"), max, got);
}
void MVM_args_checkarity(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMuint16 min, MVMuint16 max) {
    MVMuint16 num_pos = ctx->arg_info.callsite->num_pos;
    if (num_pos < min || num_pos > max)
        arity_fail(tc, num_pos, min, max);
}

/* Get positional arguments. */
#define find_pos_arg(ctx, pos, result) do { \
    if (pos < (ctx)->arg_info.callsite->num_pos) { \
        result.arg   = (ctx)->arg_info.source[(ctx)->arg_info.map[pos]]; \
        result.flags = (ctx)->arg_info.callsite->arg_flags[pos]; \
        result.exists = 1; \
    } \
    else { \
        result.arg.s = NULL; \
        result.exists = 0; \
    } \
} while (0)

static MVMObject * decont_arg(MVMThreadContext *tc, MVMObject *arg) {
    MVMContainerSpec const *contspec = STABLE(arg)->container_spec;
    if (contspec) {
        if (contspec->fetch_never_invokes) {
            MVMRegister r;
            contspec->fetch(tc, arg, &r);
            return r.o;
        }
        else {
            MVM_exception_throw_adhoc(tc, "Cannot auto-decontainerize argument");
        }
    }
    else {
        return arg;
    }
}
#define autounbox(tc, type_flag, expected, result) do { \
    if (result.exists && !(result.flags & type_flag)) { \
        if (result.flags & MVM_CALLSITE_ARG_OBJ) { \
            MVMObject *obj = decont_arg(tc, result.arg.o); \
            switch (type_flag) { \
                case MVM_CALLSITE_ARG_INT: \
                    result.arg.i64 = MVM_repr_get_int(tc, obj); \
                    result.flags = MVM_CALLSITE_ARG_INT; \
                    break; \
                case MVM_CALLSITE_ARG_NUM: \
                    result.arg.n64 = MVM_repr_get_num(tc, obj); \
                    result.flags = MVM_CALLSITE_ARG_NUM; \
                    break; \
                case MVM_CALLSITE_ARG_STR: \
                    result.arg.s = MVM_repr_get_str(tc, obj); \
                    result.flags = MVM_CALLSITE_ARG_STR; \
                    break; \
                default: \
                    MVM_exception_throw_adhoc(tc, "Failed to unbox object to " expected); \
            } \
        } \
        if (!(result.flags & type_flag)) { \
            switch (type_flag) { \
                case MVM_CALLSITE_ARG_INT: \
                    switch (result.flags & MVM_CALLSITE_ARG_TYPE_MASK) { \
                        case MVM_CALLSITE_ARG_NUM: \
                            MVM_exception_throw_adhoc(tc, "Expected native int argument, but got num"); \
                        case MVM_CALLSITE_ARG_STR: \
                            MVM_exception_throw_adhoc(tc, "Expected native int argument, but got str"); \
                        default: \
                            MVM_exception_throw_adhoc(tc, "unreachable unbox 1"); \
                    } \
                    break; \
                case MVM_CALLSITE_ARG_NUM: \
                    switch (result.flags & MVM_CALLSITE_ARG_TYPE_MASK) { \
                        case MVM_CALLSITE_ARG_INT: \
                            MVM_exception_throw_adhoc(tc, "Expected native num argument, but got int"); \
                        case MVM_CALLSITE_ARG_STR: \
                            MVM_exception_throw_adhoc(tc, "Expected native num argument, but got str"); \
                        default: \
                            MVM_exception_throw_adhoc(tc, "unreachable unbox 2"); \
                    } \
                    break; \
                case MVM_CALLSITE_ARG_STR: \
                    switch (result.flags & MVM_CALLSITE_ARG_TYPE_MASK) { \
                        case MVM_CALLSITE_ARG_INT: \
                            MVM_exception_throw_adhoc(tc, "Expected native str argument, but got int"); \
                        case MVM_CALLSITE_ARG_NUM: \
                            MVM_exception_throw_adhoc(tc, "Expected native str argument, but got num"); \
                        default: \
                            MVM_exception_throw_adhoc(tc, "unreachable unbox 3"); \
                    } \
                    break; \
                default: \
                    MVM_exception_throw_adhoc(tc, "unreachable unbox 4"); \
            } \
        } \
    } \
} while (0)

#define args_get_pos(tc, ctx, pos, required, result) do { \
    find_pos_arg(ctx, pos, result); \
    if (!result.exists && required) { \
        MVM_exception_throw_adhoc(tc, "Not enough positional arguments; needed at least %u", pos + 1); \
    } \
} while (0)

#define autobox(tc, target, result, box_type_obj, is_object, set_func, dest) do { \
    MVMObject *box, *box_type; \
    if (is_object) MVM_gc_root_temp_push(tc, (MVMCollectable **)&result); \
    box_type = target->static_info->body.cu->body.hll_config->box_type_obj; \
    box = REPR(box_type)->allocate(tc, STABLE(box_type)); \
    MVM_gc_root_temp_push(tc, (MVMCollectable **)&box); \
    if (REPR(box)->initialize) \
        REPR(box)->initialize(tc, STABLE(box), box, OBJECT_BODY(box)); \
    REPR(box)->box_funcs.set_func(tc, STABLE(box), box, OBJECT_BODY(box), result); \
    if (is_object) MVM_gc_root_temp_pop_n(tc, 2); \
    else MVM_gc_root_temp_pop(tc); \
    dest = box; \
} while (0)

#define autobox_int(tc, target, result, dest) do { \
    MVMObject *box, *box_type; \
    MVMint64 result_int = result; \
    MVMObject *autobox_temp; \
    box_type = target->static_info->body.cu->body.hll_config->int_box_type; \
    autobox_temp = MVM_intcache_get(tc, box_type, result_int); \
    if (autobox_temp == NULL) { \
        box = REPR(box_type)->allocate(tc, STABLE(box_type)); \
        MVM_gc_root_temp_push(tc, (MVMCollectable **)&box); \
        if (REPR(box)->initialize) \
            REPR(box)->initialize(tc, STABLE(box), box, OBJECT_BODY(box)); \
        REPR(box)->box_funcs.set_int(tc, STABLE(box), box, OBJECT_BODY(box), result_int); \
        MVM_gc_root_temp_pop(tc); \
        dest = box; \
    } \
    else { \
        dest = autobox_temp; \
    } \
} while (0)

#define autobox_switch(tc, result) do { \
    if (result.exists) { \
        switch (result.flags & MVM_CALLSITE_ARG_TYPE_MASK) { \
            case MVM_CALLSITE_ARG_OBJ: \
                break; \
            case MVM_CALLSITE_ARG_INT: \
                autobox_int(tc, tc->cur_frame, result.arg.i64, result.arg.o); \
                break; \
            case MVM_CALLSITE_ARG_NUM: \
                autobox(tc, tc->cur_frame, result.arg.n64, num_box_type, 0, set_num, result.arg.o); \
                break; \
            case MVM_CALLSITE_ARG_STR: \
                autobox(tc, tc->cur_frame, result.arg.s, str_box_type, 1, set_str, result.arg.o); \
                break; \
            default: \
                MVM_exception_throw_adhoc(tc, "invalid type flag"); \
        } \
    } \
} while (0)

MVMObject * MVM_args_get_required_pos_obj(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMuint32 pos) {
    MVMArgInfo result;
    args_get_pos(tc, ctx, pos, MVM_ARG_REQUIRED, result);
    autobox_switch(tc, result);
    return result.arg.o;
}
MVMArgInfo MVM_args_get_optional_pos_obj(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMuint32 pos) {
    MVMArgInfo result;
    args_get_pos(tc, ctx, pos, MVM_ARG_OPTIONAL, result);
    autobox_switch(tc, result);
    return result;
}
MVMint64 MVM_args_get_required_pos_int(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMuint32 pos) {
    MVMArgInfo result;
    args_get_pos(tc, ctx, pos, MVM_ARG_REQUIRED, result);
    autounbox(tc, MVM_CALLSITE_ARG_INT, "integer", result);
    return result.arg.i64;
}
MVMArgInfo MVM_args_get_optional_pos_int(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMuint32 pos) {
    MVMArgInfo result;
    args_get_pos(tc, ctx, pos, MVM_ARG_OPTIONAL, result);
    autounbox(tc, MVM_CALLSITE_ARG_INT, "integer", result);
    return result;
}
MVMnum64 MVM_args_get_required_pos_num(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMuint32 pos) {
    MVMArgInfo result;
    args_get_pos(tc, ctx, pos, MVM_ARG_REQUIRED, result);
    autounbox(tc, MVM_CALLSITE_ARG_NUM, "number", result);
    return result.arg.n64;
}
MVMArgInfo MVM_args_get_optional_pos_num(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMuint32 pos) {
    MVMArgInfo result;
    args_get_pos(tc, ctx, pos, MVM_ARG_OPTIONAL, result);
    autounbox(tc, MVM_CALLSITE_ARG_NUM, "number", result);
    return result;
}
MVMString * MVM_args_get_required_pos_str(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMuint32 pos) {
    MVMArgInfo result;
    args_get_pos(tc, ctx, pos, MVM_ARG_REQUIRED, result);
    autounbox(tc, MVM_CALLSITE_ARG_STR, "string", result);
    return result.arg.s;
}
MVMArgInfo MVM_args_get_optional_pos_str(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMuint32 pos) {
    MVMArgInfo result;
    args_get_pos(tc, ctx, pos, MVM_ARG_OPTIONAL, result);
    autounbox(tc, MVM_CALLSITE_ARG_STR, "string", result);
    return result;
}
MVMuint64 MVM_args_get_required_pos_uint(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMuint32 pos) {
    MVMArgInfo result;
    args_get_pos(tc, ctx, pos, MVM_ARG_REQUIRED, result);
    autounbox(tc, MVM_CALLSITE_ARG_INT, "unsigned integer", result);
    return result.arg.u64;
}
MVMArgInfo MVM_args_get_optional_pos_uint(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMuint32 pos) {
    MVMArgInfo result;
    args_get_pos(tc, ctx, pos, MVM_ARG_OPTIONAL, result);
    autounbox(tc, MVM_CALLSITE_ARG_INT, "unsigned integer", result);
    return result;
}

#define args_get_named(tc, ctx, name, required) do { \
     \
    result.arg.s = NULL; \
    result.exists = 0; \
     \
    MVMCallsite *callsite = (ctx)->arg_info.callsite; \
    MVMString **arg_names = callsite->arg_names; \
    MVMuint16 num_arg_names = callsite->flag_count - callsite->num_pos; \
    MVMuint16 i; \
    for (i = 0; i < num_arg_names; i++) { \
        if (MVM_string_equal(tc, arg_names[i], name)) { \
            MVMuint16 arg_idx = callsite->num_pos + i; \
            result.exists = 1; \
            result.arg = (ctx)->arg_info.source[(ctx)->arg_info.map[arg_idx]]; \
            result.flags = callsite->arg_flags[arg_idx]; \
            result.arg_idx = arg_idx; \
            mark_named_used(ctx, i); \
            break; \
        } \
    } \
     \
    if (!result.exists && required) { \
        char *c_name = MVM_string_utf8_encode_C_string(tc, name); \
        char *waste[] = { c_name, NULL }; \
        MVM_exception_throw_adhoc_free(tc, waste, "Required named parameter '%s' not passed", c_name); \
    } \
} while (0)

MVMArgInfo MVM_args_get_named_obj(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMString *name, MVMuint8 required) {
    MVMArgInfo result;
    args_get_named(tc, ctx, name, required);
    autobox_switch(tc, result);
    return result;
}
MVMArgInfo MVM_args_get_named_int(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMString *name, MVMuint8 required) {
    MVMArgInfo result;
    args_get_named(tc, ctx, name, required);
    autounbox(tc, MVM_CALLSITE_ARG_INT, "integer", result);
    return result;
}
MVMArgInfo MVM_args_get_named_num(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMString *name, MVMuint8 required) {
    MVMArgInfo result;
    args_get_named(tc, ctx, name, required);
    autounbox(tc, MVM_CALLSITE_ARG_NUM, "number", result);
    return result;
}
MVMArgInfo MVM_args_get_named_str(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMString *name, MVMuint8 required) {
    MVMArgInfo result;
    args_get_named(tc, ctx, name, required);
    autounbox(tc, MVM_CALLSITE_ARG_STR, "string", result);
    return result;
}
MVMArgInfo MVM_args_get_named_uint(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMString *name, MVMuint8 required) {
    MVMArgInfo result;
    args_get_named(tc, ctx, name, required);
    autounbox(tc, MVM_CALLSITE_ARG_INT, "unsigned integer", result);
    return result;
}
void MVM_args_assert_nameds_used(MVMThreadContext *tc, MVMArgProcContext *ctx) {
    MVMuint16 size = ctx->named_used_size;
    MVMuint16 i;
    if (size > 64) {
        for (i = 0; i < size; i++)
            if (!ctx->named_used.byte_array[i])
                MVM_args_throw_named_unused_error(tc, ctx->arg_info.callsite->arg_names[i]);
    }
    else {
        for (i = 0; i < size; i++)
            if (!(ctx->named_used.bit_field & ((MVMuint64)1 << i)))
                MVM_args_throw_named_unused_error(tc, ctx->arg_info.callsite->arg_names[i]);
    }
}

void MVM_args_throw_named_unused_error(MVMThreadContext *tc, MVMString *name) {
    char *c_param = MVM_string_utf8_encode_C_string(tc, name);
    char *waste[] = { c_param, NULL };
    MVM_exception_throw_adhoc_free(tc, waste,
        "Unexpected named argument '%s' passed",
        c_param);
}

/* Result setting. The frameless flag indicates that the currently
 * executing code does not have a MVMFrame of its own. */
static MVMObject * decont_result(MVMThreadContext *tc, MVMObject *result) {
    MVMContainerSpec const *contspec = STABLE(result)->container_spec;
    if (contspec) {
        if (contspec->fetch_never_invokes) {
            MVMRegister r;
            contspec->fetch(tc, result, &r);
            return r.o;
        }
        else {
            MVM_exception_throw_adhoc(tc, "Cannot auto-decontainerize return value");
        }
    }
    else {
        return result;
    }
}
void save_for_exit_handler(MVMThreadContext *tc, MVMObject *result) {
    MVMFrameExtra *e = MVM_frame_extra(tc, tc->cur_frame);
    e->exit_handler_result = result;
}
void MVM_args_set_result_obj(MVMThreadContext *tc, MVMObject *result, MVMint32 frameless) {
    MVMFrame *target;
    if (frameless) {
        target = tc->cur_frame;
    }
    else {
        MVMROOT(tc, result, {
            if (MVM_spesh_log_is_caller_logging(tc))
                MVM_spesh_log_return_type(tc, result);
            else if (MVM_spesh_log_is_logging(tc))
                MVM_spesh_log_return_to_unlogged(tc);
        });
        target = tc->cur_frame->caller;
    }
    if (target) {
        switch (target->return_type) {
            case MVM_RETURN_VOID:
                if (tc->cur_frame->static_info->body.has_exit_handler)
                    save_for_exit_handler(tc, result);
                break;
            case MVM_RETURN_OBJ:
                target->return_value->o = result;
                break;
            case MVM_RETURN_INT:
                target->return_value->i64 = MVM_repr_get_int(tc, decont_result(tc, result));
                break;
            case MVM_RETURN_NUM:
                target->return_value->n64 = MVM_repr_get_num(tc, decont_result(tc, result));
                break;
            case MVM_RETURN_STR:
                target->return_value->s = MVM_repr_get_str(tc, decont_result(tc, result));
                break;
            case MVM_RETURN_ALLOMORPH:
                target->return_type = MVM_RETURN_OBJ;
                target->return_value->o = result;
                break;
            default:
                MVM_exception_throw_adhoc(tc, "Result return coercion from obj NYI; expects type %u", target->return_type);
        }
    }
}

void MVM_args_set_dispatch_result_obj(MVMThreadContext *tc, MVMFrame *target, MVMObject *result) {
    switch (target->return_type) {
        case MVM_RETURN_VOID:
            break;
        case MVM_RETURN_OBJ:
            target->return_value->o = result;
            break;
        case MVM_RETURN_INT:
            target->return_value->i64 = MVM_repr_get_int(tc, decont_result(tc, result));
            break;
        case MVM_RETURN_NUM:
            target->return_value->n64 = MVM_repr_get_num(tc, decont_result(tc, result));
            break;
        case MVM_RETURN_STR:
            target->return_value->s = MVM_repr_get_str(tc, decont_result(tc, result));
            break;
        default:
            MVM_exception_throw_adhoc(tc, "Result return coercion from obj NYI; expects type %u", target->return_type);
    }
}

void MVM_args_set_result_int(MVMThreadContext *tc, MVMint64 result, MVMint32 frameless) {
    MVMFrame *target;
    if (frameless) {
        target = tc->cur_frame;
    }
    else {
        if (MVM_spesh_log_is_caller_logging(tc))
            MVM_spesh_log_return_type(tc, NULL);
        else if (MVM_spesh_log_is_logging(tc))
            MVM_spesh_log_return_to_unlogged(tc);
        target = tc->cur_frame->caller;
    }
    if (target) {
        switch (target->return_type) {
            case MVM_RETURN_VOID:
                if (tc->cur_frame->static_info->body.has_exit_handler)
                    save_for_exit_handler(tc,
                        MVM_repr_box_int(tc, MVM_hll_current(tc)->int_box_type, result));
                break;
            case MVM_RETURN_INT:
                target->return_value->i64 = result;
                break;
            case MVM_RETURN_NUM:
                target->return_value->n64 = (MVMnum64)result;
                break;
            case MVM_RETURN_OBJ:
                autobox_int(tc, target, result, (frameless ? tc->cur_frame : tc->cur_frame->caller)->return_value->o);
                break;
            case MVM_RETURN_ALLOMORPH:
                target->return_type = MVM_RETURN_INT;
                target->return_value->i64 = result;
                break;
            default:
                MVM_exception_throw_adhoc(tc, "Result return coercion from int NYI; expects type %u", target->return_type);
        }
    }
}

void MVM_args_set_dispatch_result_int(MVMThreadContext *tc, MVMFrame *target, MVMint64 result) {
    switch (target->return_type) {
        case MVM_RETURN_VOID:
            break;
        case MVM_RETURN_INT:
            target->return_value->i64 = result;
            break;
        case MVM_RETURN_NUM:
            target->return_value->n64 = (MVMnum64)result;
            break;
        case MVM_RETURN_OBJ:
            autobox_int(tc, target, result, target->return_value->o);
            break;
        default:
            MVM_exception_throw_adhoc(tc, "Result return coercion from int NYI; expects type %u", target->return_type);
    }
}

void MVM_args_set_result_num(MVMThreadContext *tc, MVMnum64 result, MVMint32 frameless) {
    MVMFrame *target;
    if (frameless) {
        target = tc->cur_frame;
    }
    else {
        if (MVM_spesh_log_is_caller_logging(tc))
            MVM_spesh_log_return_type(tc, NULL);
        else if (MVM_spesh_log_is_logging(tc))
            MVM_spesh_log_return_to_unlogged(tc);
        target = tc->cur_frame->caller;
    }
    if (target) {
        switch (target->return_type) {
            case MVM_RETURN_VOID:
                if (tc->cur_frame->static_info->body.has_exit_handler)
                    save_for_exit_handler(tc,
                        MVM_repr_box_int(tc, MVM_hll_current(tc)->num_box_type, result));
                break;
            case MVM_RETURN_NUM:
                target->return_value->n64 = result;
                break;
            case MVM_RETURN_INT:
                target->return_value->i64 = (MVMint64)result;
                break;
            case MVM_RETURN_OBJ:
                autobox(tc, target, result, num_box_type, 0, set_num, (frameless ? tc->cur_frame : tc->cur_frame->caller)->return_value->o);
                break;
            case MVM_RETURN_ALLOMORPH:
                target->return_type = MVM_RETURN_NUM;
                target->return_value->n64 = result;
                break;
            default:
                MVM_exception_throw_adhoc(tc, "Result return coercion from num NYI; expects type %u", target->return_type);
        }
    }
}

void MVM_args_set_dispatch_result_num(MVMThreadContext *tc, MVMFrame *target, MVMnum64 result) {
    switch (target->return_type) {
        case MVM_RETURN_VOID:
            break;
        case MVM_RETURN_NUM:
            target->return_value->n64 = result;
            break;
        case MVM_RETURN_INT:
            target->return_value->i64 = (MVMint64)result;
            break;
        case MVM_RETURN_OBJ:
            autobox(tc, target, result, num_box_type, 0, set_num, target->return_value->o);
            break;
        default:
            MVM_exception_throw_adhoc(tc, "Result return coercion from num NYI; expects type %u", target->return_type);
    }
}

void MVM_args_set_result_str(MVMThreadContext *tc, MVMString *result, MVMint32 frameless) {
    MVMFrame *target;
    if (frameless) {
        target = tc->cur_frame;
    }
    else {
        if (MVM_spesh_log_is_caller_logging(tc))
            MVMROOT(tc, result, {
                MVM_spesh_log_return_type(tc, NULL);
            });
        else if (MVM_spesh_log_is_logging(tc))
            MVMROOT(tc, result, {
                MVM_spesh_log_return_to_unlogged(tc);
            });
        target = tc->cur_frame->caller;
    }
    if (target) {
        switch (target->return_type) {
            case MVM_RETURN_VOID:
                if (tc->cur_frame->static_info->body.has_exit_handler)
                    save_for_exit_handler(tc,
                        MVM_repr_box_str(tc, MVM_hll_current(tc)->str_box_type, result));
                break;
            case MVM_RETURN_STR:
                target->return_value->s = result;
                break;
            case MVM_RETURN_OBJ:
                autobox(tc, target, result, str_box_type, 1, set_str, (frameless ? tc->cur_frame : tc->cur_frame->caller)->return_value->o);
                break;
            case MVM_RETURN_ALLOMORPH:
                target->return_type = MVM_RETURN_STR;
                target->return_value->s = result;
                break;
            default:
                MVM_exception_throw_adhoc(tc, "Result return coercion from str NYI; expects type %u", target->return_type);
        }
    }
}

void MVM_args_set_dispatch_result_str(MVMThreadContext *tc, MVMFrame *target, MVMString *result) {
    switch (target->return_type) {
        case MVM_RETURN_VOID:
            if (tc->cur_frame->static_info->body.has_exit_handler)
                save_for_exit_handler(tc,
                    MVM_repr_box_str(tc, MVM_hll_current(tc)->str_box_type, result));
            break;
        case MVM_RETURN_STR:
            target->return_value->s = result;
            break;
        case MVM_RETURN_OBJ:
            autobox(tc, target, result, str_box_type, 1, set_str, target->return_value->o);
            break;
        default:
            MVM_exception_throw_adhoc(tc, "Result return coercion from str NYI; expects type %u", target->return_type);
    }
}

void MVM_args_assert_void_return_ok(MVMThreadContext *tc, MVMint32 frameless) {
    MVMFrame *target;
    if (frameless) {
        target = tc->cur_frame;
    }
    else {
        if (MVM_spesh_log_is_caller_logging(tc))
            MVM_spesh_log_return_type(tc, NULL);
        else if (MVM_spesh_log_is_logging(tc))
            MVM_spesh_log_return_to_unlogged(tc);
        target = tc->cur_frame->caller;
    }
    if (target && target->return_type != MVM_RETURN_VOID && tc->cur_frame != tc->thread_entry_frame) {
        if (target->return_type == MVM_RETURN_ALLOMORPH) {
            target->return_type = MVM_RETURN_VOID;
            return;
        }
        MVM_exception_throw_adhoc(tc, "Void return not allowed to context requiring a return value");
    }
}

#define box_slurpy_pos(tc, type, result, box, value, reg, box_type_obj, name, set_func) do { \
    type = (*(tc->interp_cu))->body.hll_config->box_type_obj; \
    if (!type || IS_CONCRETE(type)) { \
        MVM_exception_throw_adhoc(tc, "Missing hll " name " box type"); \
    } \
    box = REPR(type)->allocate(tc, STABLE(type)); \
    if (REPR(box)->initialize) \
        REPR(box)->initialize(tc, STABLE(box), box, OBJECT_BODY(box)); \
    REPR(box)->box_funcs.set_func(tc, STABLE(box), box, \
        OBJECT_BODY(box), value); \
    reg.o = box; \
    REPR(result)->pos_funcs.push(tc, STABLE(result), result, \
        OBJECT_BODY(result), reg, MVM_reg_obj); \
} while (0)

#define box_slurpy_pos_int(tc, type, result, box, value, reg, box_type_obj, name, set_func) do { \
    type = (*(tc->interp_cu))->body.hll_config->box_type_obj; \
    if (!type || IS_CONCRETE(type)) { \
        MVM_exception_throw_adhoc(tc, "Missing hll " name " box type"); \
    } \
    box = MVM_intcache_get(tc, type, value); \
    if (!box) { \
        box = REPR(type)->allocate(tc, STABLE(type)); \
        if (REPR(box)->initialize) \
            REPR(box)->initialize(tc, STABLE(box), box, OBJECT_BODY(box)); \
        REPR(box)->box_funcs.set_func(tc, STABLE(box), box, \
            OBJECT_BODY(box), value); \
    } \
    reg.o = box; \
    REPR(result)->pos_funcs.push(tc, STABLE(result), result, \
        OBJECT_BODY(result), reg, MVM_reg_obj); \
} while (0)

MVMObject * MVM_args_slurpy_positional(MVMThreadContext *tc, MVMArgProcContext *ctx, MVMuint16 pos) {
    MVMObject *type = (*(tc->interp_cu))->body.hll_config->slurpy_array_type, *result = NULL, *box = NULL;
    MVMArgInfo arg_info;
    MVMRegister reg;

    if (!type || IS_CONCRETE(type)) {
        MVM_exception_throw_adhoc(tc, "Missing hll slurpy array type");
    }

    MVM_gc_root_temp_push(tc, (MVMCollectable **)&type);
    result = REPR(type)->allocate(tc, STABLE(type));
    MVM_gc_root_temp_push(tc, (MVMCollectable **)&result);
    if (REPR(result)->initialize)
        REPR(result)->initialize(tc, STABLE(result), result, OBJECT_BODY(result));
    MVM_gc_root_temp_push(tc, (MVMCollectable **)&box);

    find_pos_arg(ctx ? ctx : &tc->cur_frame->params, pos, arg_info);
    pos++;
    while (arg_info.exists) {

        if (arg_info.flags & MVM_CALLSITE_ARG_FLAT) {
            MVM_exception_throw_adhoc(tc, "Arg has not been flattened in slurpy_positional");
        }

        /* XXX theoretically needs to handle native arrays I guess */
        switch (arg_info.flags & MVM_CALLSITE_ARG_TYPE_MASK) {
            case MVM_CALLSITE_ARG_OBJ: {
                MVM_repr_push_o(tc, result, arg_info.arg.o);
                break;
            }
            case MVM_CALLSITE_ARG_INT:{
                box_slurpy_pos_int(tc, type, result, box, arg_info.arg.i64, reg, int_box_type, "int", set_int);
                break;
            }
            case MVM_CALLSITE_ARG_NUM: {
                box_slurpy_pos(tc, type, result, box, arg_info.arg.n64, reg, num_box_type, "num", set_num);
                break;
            }
            case MVM_CALLSITE_ARG_STR: {
                MVM_gc_root_temp_push(tc, (MVMCollectable **)&arg_info.arg.s);
                box_slurpy_pos(tc, type, result, box, arg_info.arg.s, reg, str_box_type, "str", set_str);
                MVM_gc_root_temp_pop(tc);
                break;
            }
            default:
                MVM_exception_throw_adhoc(tc, "Arg flag is empty in slurpy_positional");
        }

        find_pos_arg(ctx ? ctx : &tc->cur_frame->params, pos, arg_info);
        pos++;
        if (pos == 1) break; /* overflow?! */
    }

    MVM_gc_root_temp_pop_n(tc, 3);

    return result;
}

#define box_slurpy_named(tc, type, result, box, value, reg, box_type_obj, name, set_func, key) do { \
    type = (*(tc->interp_cu))->body.hll_config->box_type_obj; \
    if (!type || IS_CONCRETE(type)) { \
        MVM_exception_throw_adhoc(tc, "Missing hll " name " box type"); \
    } \
    box = REPR(type)->allocate(tc, STABLE(type)); \
    if (REPR(box)->initialize) \
        REPR(box)->initialize(tc, STABLE(box), box, OBJECT_BODY(box)); \
    REPR(box)->box_funcs.set_func(tc, STABLE(box), box, \
        OBJECT_BODY(box), value); \
    reg.o = box; \
    REPR(result)->ass_funcs.bind_key(tc, STABLE(result), result, \
        OBJECT_BODY(result), (MVMObject *)key, reg, MVM_reg_obj); \
} while (0)
#define box_slurpy_named_int(tc, type, result, box, value, reg, key) do { \
    type = (*(tc->interp_cu))->body.hll_config->int_box_type; \
    if (!type || IS_CONCRETE(type)) { \
        MVM_exception_throw_adhoc(tc, "Missing hll int box type"); \
    } \
    box = MVM_intcache_get(tc, type, value); \
    if (box == NULL) { \
        box = REPR(type)->allocate(tc, STABLE(type)); \
        if (REPR(box)->initialize) \
            REPR(box)->initialize(tc, STABLE(box), box, OBJECT_BODY(box)); \
        REPR(box)->box_funcs.set_int(tc, STABLE(box), box, \
            OBJECT_BODY(box), value); \
    } \
    reg.o = box; \
    REPR(result)->ass_funcs.bind_key(tc, STABLE(result), result, \
        OBJECT_BODY(result), (MVMObject *)key, reg, MVM_reg_obj); \
} while (0)

MVMObject * MVM_args_slurpy_named(MVMThreadContext *tc, MVMArgProcContext *ctx) {
    MVMObject *type = (*(tc->interp_cu))->body.hll_config->slurpy_hash_type, *result = NULL, *box = NULL;
    MVMArgInfo arg_info;
    MVMRegister reg;
    int reset_ctx = ctx == NULL;
    arg_info.exists = 0;

    if (!type || IS_CONCRETE(type)) {
        MVM_exception_throw_adhoc(tc, "Missing hll slurpy hash type");
    }

    result = REPR(type)->allocate(tc, STABLE(type));
    MVM_gc_root_temp_push(tc, (MVMCollectable **)&result);
    if (REPR(result)->initialize)
        REPR(result)->initialize(tc, STABLE(result), result, OBJECT_BODY(result));
    MVM_gc_root_temp_push(tc, (MVMCollectable **)&box);
    if (reset_ctx)
        ctx = &tc->cur_frame->params;

    MVMCallsite *cs = ctx->arg_info.callsite;
    MVMuint16 arg_idx;
    for (arg_idx = cs->num_pos; arg_idx < cs->flag_count; arg_idx++) {
        /* Skip any args already used. */
        MVMuint32 named_idx = arg_idx - cs->num_pos;
        if (is_named_used(ctx, named_idx))
            continue;

        /* Grab and check the arg name, which is to be the hash key. */
        MVMString *key = cs->arg_names[named_idx];
        if (!key || !IS_CONCRETE(key)) {
            MVM_exception_throw_adhoc(tc, "slurpy hash needs concrete key");
        }

        /* Process the value. */
        arg_info.arg = ctx->arg_info.source[ctx->arg_info.map[arg_idx]];
        arg_info.flags = cs->arg_flags[arg_idx];
        arg_info.exists = 1;
        switch (arg_info.flags & MVM_CALLSITE_ARG_TYPE_MASK) {
            case MVM_CALLSITE_ARG_OBJ: {
                REPR(result)->ass_funcs.bind_key(tc, STABLE(result),
                    result, OBJECT_BODY(result), (MVMObject *)key, arg_info.arg, MVM_reg_obj);
                if (reset_ctx)
                    ctx = &(tc->cur_frame->params);
                break;
            }
            case MVM_CALLSITE_ARG_INT: {
                MVM_gc_root_temp_push(tc, (MVMCollectable **)&key);
                box_slurpy_named_int(tc, type, result, box, arg_info.arg.i64, reg, key);
                MVM_gc_root_temp_pop(tc);
                if (reset_ctx)
                    ctx = &(tc->cur_frame->params);
                break;
            }
            case MVM_CALLSITE_ARG_NUM: {
                MVM_gc_root_temp_push(tc, (MVMCollectable **)&key);
                box_slurpy_named(tc, type, result, box, arg_info.arg.n64, reg, num_box_type, "num", set_num, key);
                MVM_gc_root_temp_pop(tc);
                if (reset_ctx)
                    ctx = &(tc->cur_frame->params);
                break;
            }
            case MVM_CALLSITE_ARG_STR: {
                MVM_gc_root_temp_push(tc, (MVMCollectable **)&key);
                MVM_gc_root_temp_push(tc, (MVMCollectable **)&arg_info.arg.s);
                box_slurpy_named(tc, type, result, box, arg_info.arg.s, reg, str_box_type, "str", set_str, key);
                MVM_gc_root_temp_pop_n(tc, 2);
                if (reset_ctx)
                    ctx = &(tc->cur_frame->params);
                break;
            }
            default:
                MVM_exception_throw_adhoc(tc, "Arg flag is empty in slurpy_named");
        }
    }

    MVM_gc_root_temp_pop_n(tc, 2);

    return result;
}

/* Custom bind failure handling. Invokes the HLL's bind failure handler, with
 * an argument capture */
static void bind_error_return(MVMThreadContext *tc, void *sr_data) {
    MVMRegister *r   = (MVMRegister *)sr_data;
    MVMObject   *res = r->o;
    MVM_free(r);
    if (tc->cur_frame->caller)
        MVM_args_set_result_obj(tc, res, 0);
    else
        MVM_exception_throw_adhoc(tc, "No caller to return to after bind_error");
    MVM_frame_try_return(tc);
}

static void bind_error_unwind(MVMThreadContext *tc, void *sr_data) {
    MVM_free(sr_data);
}

static void mark_sr_data(MVMThreadContext *tc, MVMFrame *frame, MVMGCWorklist *worklist) {
    MVMRegister *r = (MVMRegister *)frame->extra->special_return_data;
    MVM_gc_worklist_add(tc, worklist, &r->o);
}
void MVM_args_bind_failed(MVMThreadContext *tc, MVMDispInlineCacheEntry **ice_ptr) {
    /* There are two situations we may be in. Either we are doing a dispatch
     * that wishes to resume upon a bind failure, or we need to trigger the
     * bind failure handler. This is determined by if there is a bind failure
     * frame under us on the callstack in a fresh state. */
    MVMCallStackRecord *under_us = tc->stack_top->prev;
    while (under_us->kind == MVM_CALLSTACK_RECORD_START_REGION)
        under_us = under_us->prev;
    if (under_us->kind == MVM_CALLSTACK_RECORD_BIND_CONTROL) {
        MVMCallStackBindControl *control_record = (MVMCallStackBindControl *)under_us;
        MVMBindControlState state = control_record->state;
        if (state == MVM_BIND_CONTROL_FRESH_FAIL || state == MVM_BIND_CONTROL_FRESH_ALL) {
            /* The dispatch resumption case. Flag the failure, then do a return
             * without running an exit handlers. */
            control_record->state = MVM_BIND_CONTROL_FAILED;
            control_record->ice_ptr = ice_ptr;
            control_record->sf = tc->cur_frame->static_info;
            MVM_frame_try_return_no_exit_handlers(tc);
            return;
        }
    }

    /* If we get here, it's the error case. Capture arguments into a call
     * capture, to pass off for analysis. */
    MVMObject *cc_obj = MVM_args_save_capture(tc, tc->cur_frame);

    /* Invoke the HLL's bind failure handler. */
    MVMFrame *cur_frame = tc->cur_frame;
    MVMCode *bind_error = MVM_hll_current(tc)->bind_error;
    if (!bind_error)
        MVM_exception_throw_adhoc(tc, "Bind error occurred, but HLL has no handler");
    MVMRegister *res = MVM_calloc(1, sizeof(MVMRegister));
    MVM_frame_special_return(tc, cur_frame, bind_error_return, bind_error_unwind, res, mark_sr_data);
    MVMCallStackArgsFromC *args_record = MVM_callstack_allocate_args_from_c(tc,
            MVM_callsite_get_common(tc, MVM_CALLSITE_ID_OBJ));
    args_record->args.source[0].o = cc_obj;
    MVM_frame_dispatch_from_c(tc, bind_error, args_record, res, MVM_RETURN_OBJ);
}

/* Called when args binding is completed successfully. A no-op unless we're
 * below a bind control record that wants to turn bind success into a
 * dispatch resumption. */
void MVM_args_bind_succeeded(MVMThreadContext *tc, MVMDispInlineCacheEntry **ice_ptr) {
    MVMCallStackRecord *under_us = tc->stack_top->prev;
    while (under_us->kind == MVM_CALLSTACK_RECORD_START_REGION)
        under_us = under_us->prev;
    if (under_us->kind == MVM_CALLSTACK_RECORD_BIND_CONTROL) {
        MVMCallStackBindControl *control_record = (MVMCallStackBindControl *)under_us;
        MVMBindControlState state = control_record->state;
        if (state == MVM_BIND_CONTROL_FRESH_ALL) {
            control_record->state = MVM_BIND_CONTROL_SUCCEEDED;
            control_record->ice_ptr = ice_ptr;
            control_record->sf = tc->cur_frame->static_info;
            MVM_frame_try_return_no_exit_handlers(tc);
            return;
        }
    }
}