Files
nix-js/fix-vm/src/instructions/collections.rs
T

322 lines
9.9 KiB
Rust

use fix_common::StringId;
use fix_error::Error;
use gc_arena::{Gc, RefLock};
use smallvec::SmallVec;
use crate::value::NixType;
use crate::{
AttrKeyData, AttrSet, BytecodeReader, List, OperandData, Step, StrictValue, Value,
VmRuntimeCtx, VmRuntimeCtxExt,
};
impl<'gc> crate::Vm<'gc> {
#[inline(always)]
pub(crate) fn op_make_attrs(
&mut self,
ctx: &mut impl VmRuntimeCtx,
reader: &mut BytecodeReader<'_>,
mc: &gc_arena::Mutation<'gc>,
) -> Step {
let count = reader.read_u32() as usize;
let mut entries: SmallVec<[AttrEntry; 4]> = SmallVec::with_capacity(count);
for _ in 0..count {
let key = reader.read_attr_key_data(ctx);
let val = reader.read_operand_data(ctx);
let _span_id = reader.read_u32();
entries.push(AttrEntry { key, val });
}
let mut kv: SmallVec<[(crate::StringId, Value); 4]> = SmallVec::with_capacity(count);
for entry in &entries {
let key_sid = match &entry.key {
AttrKeyData::Static(sid) => *sid,
AttrKeyData::Dynamic(op) => {
let v = op.resolve(mc, self);
v.as_inline::<crate::StringId>()
.expect("dynamic attr key must be a string")
}
};
let val = entry.val.resolve(mc, self);
kv.push((key_sid, val));
}
kv.sort_by_key(|(k, _)| *k);
let attrs = Gc::new(mc, AttrSet::from_sorted_unchecked(kv));
self.push(Value::new_gc(attrs));
Step::Continue(())
}
#[inline(always)]
pub(crate) fn op_make_empty_attrs(&mut self) -> Step {
self.push(self.empty_attrs);
Step::Continue(())
}
#[inline(always)]
pub(crate) fn op_select_static(
&mut self,
ctx: &mut impl VmRuntimeCtx,
reader: &mut BytecodeReader<'_>,
mc: &gc_arena::Mutation<'gc>,
) -> Step {
let _span_id = reader.read_u32();
let key = reader.read_string_id();
let attrset = self.try_force::<Gc<AttrSet>>(reader, mc)?;
match attrset.lookup(key) {
Some(v) => {
self.push(v);
}
None => return self.select_skip(key, ctx, reader),
}
Step::Continue(())
}
#[inline(always)]
pub(crate) fn op_select_dynamic(
&mut self,
ctx: &mut impl VmRuntimeCtx,
reader: &mut BytecodeReader<'_>,
mc: &gc_arena::Mutation<'gc>,
) -> Step {
let _span_id = reader.read_u32();
let (attrset, key_val) = self.try_force::<(Gc<AttrSet>, StrictValue)>(reader, mc)?;
let key_sid = match ctx.get_string_id(key_val) {
Ok(id) => id,
Err(got) => return self.finish_type_err(NixType::String, got),
};
match attrset.lookup(key_sid) {
Some(v) => {
self.push(v);
}
None => return self.select_skip(key_sid, ctx, reader),
}
Step::Continue(())
}
/// Skip the rest of a **Select** attrpath after a missing attribute.
/// Only recognises Select opcodes and jumps; encountering any other
/// opcode means we've reached the end of the select sequence and
/// should report the missing-attribute error.
fn select_skip(
&mut self,
key: StringId,
ctx: &mut impl VmRuntimeCtx,
reader: &mut BytecodeReader<'_>,
) -> Step {
use fix_codegen::Op::*;
loop {
match reader.read_op() {
SelectStatic => {
reader.set_pc(reader.pc() + 4 + 4);
}
SelectDynamic => {
reader.set_pc(reader.pc() + 4);
}
JumpIfSelectSucceeded => {
reader.set_pc(reader.pc() + 4);
break Step::Continue(());
}
JumpIfSelectFailed => {
let offset = reader.read_i32();
reader.set_pc(((reader.pc() as isize) + (offset as isize)) as usize);
}
_ => {
let name = ctx.resolve_string(key);
return self
.finish_err(Error::eval_error(format!("attribute '{name}' missing")));
}
}
}
}
/// Skip the rest of a **HasAttr** attrpath after an intermediate
/// lookup failed. Only recognises HasAttr opcodes and jumps.
fn has_attr_skip(&mut self, reader: &mut BytecodeReader<'_>) -> Step {
use fix_codegen::Op::*;
loop {
match reader.read_op() {
HasAttrPathStatic => {
reader.set_pc(reader.pc() + 4 + 4);
}
HasAttrPathDynamic => {
reader.set_pc(reader.pc() + 4);
}
HasAttrStatic => {
reader.set_pc(reader.pc() + 4);
break Step::Continue(());
}
JumpIfSelectFailed => {
let offset = reader.read_i32();
reader.set_pc(((reader.pc() as isize) + (offset as isize)) as usize);
}
HasAttrDynamic => {
break Step::Continue(());
}
HasAttrResolve => {
reader.set_pc(reader.pc() - 1);
break Step::Continue(());
}
other => {
unreachable!("unexpected opcode {:?} in has_attr_skip", other as u8)
}
}
}
}
#[inline(always)]
pub(crate) fn op_has_attr_path_static(
&mut self,
_ctx: &mut impl VmRuntimeCtx,
reader: &mut BytecodeReader<'_>,
mc: &gc_arena::Mutation<'gc>,
) -> Step {
let _span_id = reader.read_u32();
let key = reader.read_string_id();
let current = self.try_force::<StrictValue>(reader, mc)?;
match current
.as_gc::<AttrSet>()
.and_then(|attrs| attrs.lookup(key))
{
Some(v) => {
self.push(v);
}
None => return self.has_attr_skip(reader),
}
Step::Continue(())
}
#[inline(always)]
pub(crate) fn op_has_attr_path_dynamic(
&mut self,
ctx: &mut impl VmRuntimeCtx,
reader: &mut BytecodeReader<'_>,
mc: &gc_arena::Mutation<'gc>,
) -> Step {
let _span_id = reader.read_u32();
let (current, key_val) = self.try_force::<(StrictValue, StrictValue)>(reader, mc)?;
let key_sid = match ctx.get_string_id(key_val) {
Ok(id) => id,
Err(got) => return self.finish_type_err(NixType::String, got),
};
match current
.as_gc::<AttrSet>()
.and_then(|attrs| attrs.lookup(key_sid))
{
Some(v) => {
self.push(v);
}
None => return self.has_attr_skip(reader),
}
Step::Continue(())
}
#[inline(always)]
pub(crate) fn op_jump_if_select_failed(&mut self, reader: &mut BytecodeReader<'_>) -> Step {
// No-op
let _offset = reader.read_i32();
Step::Continue(())
}
#[inline(always)]
pub(crate) fn op_jump_if_select_succeeded(&mut self, reader: &mut BytecodeReader<'_>) -> Step {
let offset = reader.read_i32();
reader.set_pc(((reader.pc() as isize) + (offset as isize)) as usize);
Step::Continue(())
}
#[inline(always)]
pub(crate) fn op_has_attr_static(
&mut self,
reader: &mut BytecodeReader<'_>,
mc: &gc_arena::Mutation<'gc>,
) -> Step {
let key = reader.read_string_id();
let current = self.try_force::<StrictValue>(reader, mc)?;
self.push(Value::new_inline(
current
.as_gc::<AttrSet>()
.and_then(|attrs| attrs.lookup(key))
.is_some(),
));
// Skip HasAttrResolve
reader.set_pc(reader.pc() + 1);
Step::Continue(())
}
#[inline(always)]
pub(crate) fn op_has_attr_dynamic(
&mut self,
ctx: &mut impl VmRuntimeCtx,
reader: &mut BytecodeReader<'_>,
mc: &gc_arena::Mutation<'gc>,
) -> Step {
let (current, dyn_key) = self.try_force::<(StrictValue, StrictValue)>(reader, mc)?;
let key_sid = match ctx.get_string_id(dyn_key) {
Ok(id) => id,
Err(got) => return self.finish_type_err(NixType::String, got),
};
self.push(Value::new_inline(
current
.as_gc::<AttrSet>()
.and_then(|attrs| attrs.lookup(key_sid))
.is_some(),
));
// Skip HasAttrResolve
reader.set_pc(reader.pc() + 1);
Step::Continue(())
}
#[inline(always)]
pub(crate) fn op_has_attr_resolve(&mut self) -> Step {
// If we reach here, has_attr check has failed, push false (AttrSet is already popped)
self.push(Value::new_inline(false));
Step::Continue(())
}
#[inline(always)]
pub(crate) fn op_make_list(
&mut self,
ctx: &mut impl VmRuntimeCtx,
reader: &mut BytecodeReader<'_>,
mc: &gc_arena::Mutation<'gc>,
) -> Step {
let count = reader.read_u32() as usize;
let mut items: SmallVec<[Value; 4]> = SmallVec::with_capacity(count);
for _ in 0..count {
items.push(reader.read_operand_data(ctx).resolve(mc, self));
}
let list = Gc::new(
mc,
List {
inner: RefLock::new(items),
},
);
self.push(Value::new_gc(list));
Step::Continue(())
}
#[inline(always)]
pub(crate) fn op_make_empty_list(&mut self) -> Step {
self.push(self.empty_list);
Step::Continue(())
}
}
pub(crate) struct AttrEntry {
pub(crate) key: AttrKeyData,
pub(crate) val: OperandData,
}