refactor(tvix/eval): add opcode::StackIdx type for less ambiguity

Change-Id: I9b9de1f681972c205d4d20bc5731d2ce79858edb
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6287
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
This commit is contained in:
Vincent Ambo 2022-08-26 20:54:39 +03:00 committed by tazjin
parent 2cdc6192b4
commit c73e84d957
3 changed files with 14 additions and 9 deletions

View file

@ -22,7 +22,7 @@ use std::rc::Rc;
use crate::chunk::Chunk;
use crate::errors::{Error, ErrorKind, EvalResult};
use crate::opcode::{CodeIdx, JumpOffset, OpCode};
use crate::opcode::{CodeIdx, JumpOffset, OpCode, StackIdx};
use crate::value::{Closure, Lambda, Value};
use crate::warnings::{EvalWarning, WarningKind};
@ -116,11 +116,11 @@ impl Scope {
}
/// Resolve the stack index of a statically known local.
fn resolve_local(&mut self, name: &str) -> Option<usize> {
fn resolve_local(&mut self, name: &str) -> Option<StackIdx> {
for (idx, local) in self.locals.iter_mut().enumerate().rev() {
if !local.phantom && local.name == name {
local.used = true;
return Some(idx);
return Some(StackIdx(idx));
}
}
@ -799,7 +799,7 @@ impl Compiler {
self.scope_mut().with_stack.push(With { depth });
let with_idx = self.scope().locals.len() - 1;
self.chunk().push_op(OpCode::OpPushWith(with_idx));
self.chunk().push_op(OpCode::OpPushWith(StackIdx(with_idx)));
self.compile(node.body().unwrap());
}

View file

@ -11,6 +11,11 @@ pub struct ConstantIdx(pub usize);
#[derive(Clone, Copy, Debug)]
pub struct CodeIdx(pub usize);
/// Index of a value in the runtime stack.
#[repr(transparent)]
#[derive(Clone, Copy, Debug)]
pub struct StackIdx(pub usize);
/// Offset by which an instruction pointer should change in a jump.
#[repr(transparent)]
#[derive(Clone, Copy, Debug)]
@ -63,7 +68,7 @@ pub enum OpCode {
OpAttrsIsSet,
// `with`-handling
OpPushWith(usize),
OpPushWith(StackIdx),
OpPopWith,
OpResolveWith,
@ -78,7 +83,7 @@ pub enum OpCode {
OpAssertBool,
// Access local identifiers with statically known positions.
OpGetLocal(usize),
OpGetLocal(StackIdx),
// Close scopes while leaving their expression value around.
OpCloseScope(usize), // number of locals to pop

View file

@ -6,7 +6,7 @@ use std::rc::Rc;
use crate::{
chunk::Chunk,
errors::{ErrorKind, EvalResult},
opcode::{JumpOffset, OpCode},
opcode::{JumpOffset, OpCode, StackIdx},
value::{Closure, Lambda, NixAttrs, NixList, Value},
};
@ -318,13 +318,13 @@ impl VM {
}
}
OpCode::OpGetLocal(local_idx) => {
OpCode::OpGetLocal(StackIdx(local_idx)) => {
let idx = self.frame().stack_offset + local_idx;
let value = self.stack[idx].clone();
self.push(value)
}
OpCode::OpPushWith(idx) => self.with_stack.push(idx),
OpCode::OpPushWith(StackIdx(idx)) => self.with_stack.push(idx),
OpCode::OpPopWith => {
self.with_stack.pop();
}