1394 lines
54 KiB
Rust
1394 lines
54 KiB
Rust
//! Module implementing the [`AST`] optimizer.
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#![cfg(not(feature = "no_optimize"))]
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use crate::ast::{
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ASTFlags, Expr, FlowControl, OpAssignment, Stmt, StmtBlock, StmtBlockContainer,
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SwitchCasesCollection,
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};
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use crate::engine::{
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KEYWORD_DEBUG, KEYWORD_EVAL, KEYWORD_FN_PTR, KEYWORD_PRINT, KEYWORD_TYPE_OF, OP_NOT,
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};
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use crate::eval::{Caches, GlobalRuntimeState};
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use crate::func::builtin::get_builtin_binary_op_fn;
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use crate::func::hashing::get_hasher;
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use crate::module::ModuleFlags;
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use crate::tokenizer::Token;
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use crate::types::dynamic::AccessMode;
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use crate::{
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calc_fn_hash, calc_fn_hash_full, Dynamic, Engine, FnPtr, Identifier, ImmutableString, Position,
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Scope, StaticVec, AST,
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};
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#[cfg(feature = "no_std")]
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use std::prelude::v1::*;
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use std::{
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any::TypeId,
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convert::TryFrom,
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hash::{Hash, Hasher},
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mem,
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};
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/// Level of optimization performed.
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#[derive(Debug, Eq, PartialEq, Hash, Clone, Copy)]
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#[non_exhaustive]
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pub enum OptimizationLevel {
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/// No optimization performed.
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None,
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/// Only perform simple optimizations without evaluating functions.
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Simple,
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/// Full optimizations performed, including evaluating functions.
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/// Take care that this may cause side effects as it essentially assumes that all functions are pure.
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Full,
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}
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impl Default for OptimizationLevel {
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#[inline(always)]
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#[must_use]
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fn default() -> Self {
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Self::Simple
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}
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}
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/// Mutable state throughout an optimization pass.
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#[derive(Debug, Clone)]
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struct OptimizerState<'a> {
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/// Has the [`AST`] been changed during this pass?
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changed: bool,
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/// Collection of constants to use for eager function evaluations.
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variables: StaticVec<(Identifier, AccessMode, Option<Dynamic>)>,
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/// Activate constants propagation?
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propagate_constants: bool,
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/// An [`Engine`] instance for eager function evaluation.
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engine: &'a Engine,
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/// The global runtime state.
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global: GlobalRuntimeState,
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/// Function resolution caches.
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caches: Caches,
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/// Optimization level.
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optimization_level: OptimizationLevel,
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}
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impl<'a> OptimizerState<'a> {
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/// Create a new [`OptimizerState`].
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#[inline(always)]
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pub fn new(
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engine: &'a Engine,
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lib: &'a [crate::SharedModule],
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optimization_level: OptimizationLevel,
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) -> Self {
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let mut _global = GlobalRuntimeState::new(engine);
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let _lib = lib;
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#[cfg(not(feature = "no_function"))]
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{
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_global.lib = _lib.iter().cloned().collect();
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}
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Self {
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changed: false,
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variables: StaticVec::new_const(),
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propagate_constants: true,
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engine,
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global: _global,
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caches: Caches::new(),
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optimization_level,
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}
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}
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/// Set the [`AST`] state to be dirty (i.e. changed).
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#[inline(always)]
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pub fn set_dirty(&mut self) {
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self.changed = true;
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}
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/// Set the [`AST`] state to be not dirty (i.e. unchanged).
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#[inline(always)]
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pub fn clear_dirty(&mut self) {
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self.changed = false;
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}
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/// Is the [`AST`] dirty (i.e. changed)?
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#[inline(always)]
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pub const fn is_dirty(&self) -> bool {
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self.changed
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}
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/// Prune the list of constants back to a specified size.
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#[inline(always)]
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pub fn restore_var(&mut self, len: usize) {
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self.variables.truncate(len);
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}
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/// Add a new variable to the list.
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#[inline(always)]
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pub fn push_var(
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&mut self,
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name: impl Into<Identifier>,
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access: AccessMode,
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value: Option<Dynamic>,
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) {
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self.variables.push((name.into(), access, value));
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}
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/// Look up a constant from the list.
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#[inline]
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pub fn find_constant(&self, name: &str) -> Option<&Dynamic> {
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if !self.propagate_constants {
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return None;
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}
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for (n, access, value) in self.variables.iter().rev() {
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if n == name {
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return match access {
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AccessMode::ReadWrite => None,
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AccessMode::ReadOnly => value.as_ref(),
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};
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}
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}
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None
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}
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/// Call a registered function
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#[inline]
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pub fn call_fn_with_constant_arguments(
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&mut self,
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fn_name: &str,
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op_token: Option<&Token>,
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arg_values: &mut [Dynamic],
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) -> Option<Dynamic> {
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self.engine
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.exec_native_fn_call(
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&mut self.global,
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&mut self.caches,
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fn_name,
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op_token,
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calc_fn_hash(None, fn_name, arg_values.len()),
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&mut arg_values.iter_mut().collect::<StaticVec<_>>(),
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false,
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Position::NONE,
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)
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.ok()
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.map(|(v, ..)| v)
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}
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}
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/// Optimize a block of [statements][Stmt].
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fn optimize_stmt_block(
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mut statements: StmtBlockContainer,
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state: &mut OptimizerState,
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preserve_result: bool,
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is_internal: bool,
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reduce_return: bool,
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) -> StmtBlockContainer {
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if statements.is_empty() {
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return statements;
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}
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let mut is_dirty = state.is_dirty();
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let is_pure = if is_internal {
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Stmt::is_internally_pure
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} else {
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Stmt::is_pure
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};
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// Flatten blocks
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while let Some(n) = statements.iter().position(
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|s| matches!(s, Stmt::Block(block, ..) if !block.iter().any(Stmt::is_block_dependent)),
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) {
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let (first, second) = statements.split_at_mut(n);
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let stmt = mem::take(&mut second[0]);
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let mut stmts = match stmt {
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Stmt::Block(block, ..) => block,
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stmt => unreachable!("Stmt::Block expected but gets {:?}", stmt),
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};
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statements = first
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.iter_mut()
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.map(mem::take)
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.chain(stmts.iter_mut().map(mem::take))
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.chain(second.iter_mut().skip(1).map(mem::take))
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.collect();
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is_dirty = true;
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}
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// Optimize
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loop {
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state.clear_dirty();
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let orig_constants_len = state.variables.len(); // Original number of constants in the state, for restore later
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let orig_propagate_constants = state.propagate_constants;
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// Remove everything following control flow breaking statements
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let mut dead_code = false;
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statements.retain(|stmt| {
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if dead_code {
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state.set_dirty();
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false
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} else if stmt.is_control_flow_break() {
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dead_code = true;
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true
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} else {
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true
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}
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});
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// Optimize each statement in the block
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statements.iter_mut().for_each(|stmt| {
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match stmt {
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Stmt::Var(x, options, ..) => {
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if options.contains(ASTFlags::CONSTANT) {
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// Add constant literals into the state
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optimize_expr(&mut x.1, state, false);
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if x.1.is_constant() {
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state.push_var(
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x.0.as_str(),
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AccessMode::ReadOnly,
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x.1.get_literal_value(),
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);
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}
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} else {
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// Add variables into the state
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optimize_expr(&mut x.1, state, false);
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state.push_var(x.0.as_str(), AccessMode::ReadWrite, None);
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}
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}
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// Optimize the statement
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_ => optimize_stmt(stmt, state, preserve_result),
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}
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});
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// Remove all pure statements except the last one
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let mut index = 0;
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let mut first_non_constant = statements
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.iter()
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.rev()
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.enumerate()
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.find_map(|(i, stmt)| match stmt {
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stmt if !is_pure(stmt) => Some(i),
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Stmt::Var(x, ..) if x.1.is_constant() => Some(i),
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Stmt::Expr(e) if !e.is_constant() => Some(i),
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#[cfg(not(feature = "no_module"))]
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Stmt::Import(x, ..) if !x.0.is_constant() => Some(i),
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_ => None,
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})
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.map_or(0, |n| statements.len() - n - 1);
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while index < statements.len() {
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if preserve_result && index >= statements.len() - 1 {
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break;
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}
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match statements[index] {
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ref stmt if is_pure(stmt) && index >= first_non_constant => {
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state.set_dirty();
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statements.remove(index);
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}
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ref stmt if stmt.is_pure() => {
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state.set_dirty();
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if index < first_non_constant {
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first_non_constant -= 1;
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}
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statements.remove(index);
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}
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_ => index += 1,
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}
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}
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// Remove all pure statements that do not return values at the end of a block.
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// We cannot remove anything for non-pure statements due to potential side-effects.
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if preserve_result {
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loop {
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match statements[..] {
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// { return; } -> {}
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[Stmt::Return(None, options, ..)]
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if reduce_return && !options.contains(ASTFlags::BREAK) =>
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{
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state.set_dirty();
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statements.clear();
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}
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[ref stmt] if !stmt.returns_value() && is_pure(stmt) => {
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state.set_dirty();
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statements.clear();
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}
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// { ...; return; } -> { ... }
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[.., ref last_stmt, Stmt::Return(None, options, ..)]
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if reduce_return
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&& !options.contains(ASTFlags::BREAK)
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&& !last_stmt.returns_value() =>
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{
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state.set_dirty();
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statements.pop().unwrap();
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}
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// { ...; return val; } -> { ...; val }
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[.., Stmt::Return(ref mut expr, options, pos)]
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if reduce_return && !options.contains(ASTFlags::BREAK) =>
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{
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state.set_dirty();
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*statements.last_mut().unwrap() = expr
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.as_mut()
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.map_or_else(|| Stmt::Noop(pos), |e| Stmt::Expr(mem::take(e)));
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}
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// { ...; stmt; noop } -> done
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[.., ref second_last_stmt, Stmt::Noop(..)]
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if second_last_stmt.returns_value() =>
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{
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break
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}
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// { ...; stmt_that_returns; pure_non_value_stmt } -> { ...; stmt_that_returns; noop }
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// { ...; stmt; pure_non_value_stmt } -> { ...; stmt }
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[.., ref second_last_stmt, ref last_stmt]
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if !last_stmt.returns_value() && is_pure(last_stmt) =>
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{
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state.set_dirty();
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if second_last_stmt.returns_value() {
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*statements.last_mut().unwrap() = Stmt::Noop(last_stmt.position());
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} else {
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statements.pop().unwrap();
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}
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}
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_ => break,
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}
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}
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} else {
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loop {
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match statements[..] {
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[ref stmt] if is_pure(stmt) => {
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state.set_dirty();
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statements.clear();
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}
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// { ...; return; } -> { ... }
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[.., Stmt::Return(None, options, ..)]
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if reduce_return && !options.contains(ASTFlags::BREAK) =>
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{
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state.set_dirty();
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statements.pop().unwrap();
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}
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// { ...; return pure_val; } -> { ... }
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[.., Stmt::Return(Some(ref expr), options, ..)]
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if reduce_return
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&& !options.contains(ASTFlags::BREAK)
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&& expr.is_pure() =>
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{
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state.set_dirty();
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statements.pop().unwrap();
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}
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[.., ref last_stmt] if is_pure(last_stmt) => {
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state.set_dirty();
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statements.pop().unwrap();
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}
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_ => break,
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}
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}
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}
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// Pop the stack and remove all the local constants
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state.restore_var(orig_constants_len);
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state.propagate_constants = orig_propagate_constants;
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if !state.is_dirty() {
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break;
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}
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is_dirty = true;
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}
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if is_dirty {
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state.set_dirty();
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}
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statements.shrink_to_fit();
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statements
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}
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/// Optimize a [statement][Stmt].
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fn optimize_stmt(stmt: &mut Stmt, state: &mut OptimizerState, preserve_result: bool) {
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match stmt {
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// var = var op expr => var op= expr
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Stmt::Assignment(x, ..)
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if !x.0.is_op_assignment()
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&& x.1.lhs.is_variable_access(true)
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&& matches!(&x.1.rhs, Expr::FnCall(x2, ..)
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if Token::lookup_symbol_from_syntax(&x2.name).map_or(false, |t| t.has_op_assignment())
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&& x2.args.len() == 2
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&& x2.args[0].get_variable_name(true) == x.1.lhs.get_variable_name(true)
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) =>
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{
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match x.1.rhs {
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Expr::FnCall(ref mut x2, pos) => {
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state.set_dirty();
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x.0 = OpAssignment::new_op_assignment_from_base(&x2.name, pos);
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x.1.rhs = mem::take(&mut x2.args[1]);
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}
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ref expr => unreachable!("Expr::FnCall expected but gets {:?}", expr),
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}
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}
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// expr op= expr
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Stmt::Assignment(x, ..) => {
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if !x.1.lhs.is_variable_access(false) {
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optimize_expr(&mut x.1.lhs, state, false);
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}
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optimize_expr(&mut x.1.rhs, state, false);
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}
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// if expr {}
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Stmt::If(x, ..) if x.body.is_empty() && x.branch.is_empty() => {
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let condition = &mut x.expr;
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state.set_dirty();
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let pos = condition.start_position();
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let mut expr = mem::take(condition);
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optimize_expr(&mut expr, state, false);
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*stmt = if preserve_result {
|
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// -> { expr, Noop }
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(
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[Stmt::Expr(expr.into()), Stmt::Noop(pos)],
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pos,
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Position::NONE,
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)
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.into()
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} else {
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// -> expr
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Stmt::Expr(expr.into())
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};
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}
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// if false { if_block } -> Noop
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Stmt::If(x, ..)
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if matches!(x.expr, Expr::BoolConstant(false, ..)) && x.branch.is_empty() =>
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{
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if let Expr::BoolConstant(false, pos) = x.expr {
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state.set_dirty();
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*stmt = Stmt::Noop(pos);
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} else {
|
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unreachable!("`Expr::BoolConstant`");
|
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}
|
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}
|
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// if false { if_block } else { else_block } -> else_block
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Stmt::If(x, ..) if matches!(x.expr, Expr::BoolConstant(false, ..)) => {
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state.set_dirty();
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let body = mem::take(&mut *x.branch);
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*stmt = match optimize_stmt_block(body, state, preserve_result, true, false) {
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statements if statements.is_empty() => Stmt::Noop(x.branch.position()),
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statements => (statements, x.branch.span()).into(),
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}
|
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}
|
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// if true { if_block } else { else_block } -> if_block
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Stmt::If(x, ..) if matches!(x.expr, Expr::BoolConstant(true, ..)) => {
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state.set_dirty();
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let body = mem::take(&mut *x.body);
|
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*stmt = match optimize_stmt_block(body, state, preserve_result, true, false) {
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statements if statements.is_empty() => Stmt::Noop(x.body.position()),
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statements => (statements, x.body.span()).into(),
|
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}
|
|
}
|
|
// if expr { if_block } else { else_block }
|
|
Stmt::If(x, ..) => {
|
|
let FlowControl { expr, body, branch } = &mut **x;
|
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optimize_expr(expr, state, false);
|
|
let statements = mem::take(&mut **body);
|
|
**body = optimize_stmt_block(statements, state, preserve_result, true, false);
|
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let statements = mem::take(&mut **branch);
|
|
**branch = optimize_stmt_block(statements, state, preserve_result, true, false);
|
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}
|
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|
|
// switch const { ... }
|
|
Stmt::Switch(x, pos) if x.0.is_constant() => {
|
|
let (
|
|
match_expr,
|
|
SwitchCasesCollection {
|
|
expressions,
|
|
cases,
|
|
ranges,
|
|
def_case,
|
|
},
|
|
) = &mut **x;
|
|
|
|
let value = match_expr.get_literal_value().unwrap();
|
|
let hasher = &mut get_hasher();
|
|
value.hash(hasher);
|
|
let hash = hasher.finish();
|
|
|
|
// First check hashes
|
|
if let Some(case_blocks_list) = cases.get(&hash) {
|
|
match &case_blocks_list[..] {
|
|
[] => (),
|
|
[index] => {
|
|
let mut b = mem::take(&mut expressions[*index]);
|
|
cases.clear();
|
|
|
|
if b.is_always_true() {
|
|
// Promote the matched case
|
|
let mut statements = Stmt::Expr(mem::take(&mut b.expr).into());
|
|
optimize_stmt(&mut statements, state, true);
|
|
*stmt = statements;
|
|
} else {
|
|
// switch const { case if condition => stmt, _ => def } => if condition { stmt } else { def }
|
|
optimize_expr(&mut b.condition, state, false);
|
|
|
|
let branch = match def_case {
|
|
Some(index) => {
|
|
let mut def_stmt =
|
|
Stmt::Expr(mem::take(&mut expressions[*index].expr).into());
|
|
optimize_stmt(&mut def_stmt, state, true);
|
|
def_stmt.into()
|
|
}
|
|
_ => StmtBlock::NONE,
|
|
};
|
|
let body = Stmt::Expr(mem::take(&mut b.expr).into()).into();
|
|
let expr = mem::take(&mut b.condition);
|
|
|
|
*stmt = Stmt::If(
|
|
FlowControl { expr, body, branch }.into(),
|
|
match_expr.start_position(),
|
|
);
|
|
}
|
|
|
|
state.set_dirty();
|
|
return;
|
|
}
|
|
_ => {
|
|
for &index in case_blocks_list {
|
|
let mut b = mem::take(&mut expressions[index]);
|
|
|
|
if b.is_always_true() {
|
|
// Promote the matched case
|
|
let mut statements = Stmt::Expr(mem::take(&mut b.expr).into());
|
|
optimize_stmt(&mut statements, state, true);
|
|
*stmt = statements;
|
|
state.set_dirty();
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Then check ranges
|
|
if !ranges.is_empty() {
|
|
// Only one range or all ranges without conditions
|
|
if ranges.len() == 1
|
|
|| ranges
|
|
.iter()
|
|
.all(|r| expressions[r.index()].is_always_true())
|
|
{
|
|
if let Some(r) = ranges.iter().find(|r| r.contains(&value)) {
|
|
let range_block = &mut expressions[r.index()];
|
|
|
|
if range_block.is_always_true() {
|
|
// Promote the matched case
|
|
let block = &mut expressions[r.index()];
|
|
let mut statements = Stmt::Expr(mem::take(&mut block.expr).into());
|
|
optimize_stmt(&mut statements, state, true);
|
|
*stmt = statements;
|
|
} else {
|
|
let mut expr = mem::take(&mut range_block.condition);
|
|
|
|
// switch const { range if condition => stmt, _ => def } => if condition { stmt } else { def }
|
|
optimize_expr(&mut expr, state, false);
|
|
|
|
let branch = match def_case {
|
|
Some(index) => {
|
|
let mut def_stmt =
|
|
Stmt::Expr(mem::take(&mut expressions[*index].expr).into());
|
|
optimize_stmt(&mut def_stmt, state, true);
|
|
def_stmt.into()
|
|
}
|
|
_ => StmtBlock::NONE,
|
|
};
|
|
|
|
let body =
|
|
Stmt::Expr(mem::take(&mut expressions[r.index()].expr).into())
|
|
.into();
|
|
|
|
*stmt = Stmt::If(
|
|
FlowControl { expr, body, branch }.into(),
|
|
match_expr.start_position(),
|
|
);
|
|
}
|
|
|
|
state.set_dirty();
|
|
return;
|
|
}
|
|
} else {
|
|
// Multiple ranges - clear the table and just keep the right ranges
|
|
if !cases.is_empty() {
|
|
state.set_dirty();
|
|
cases.clear();
|
|
}
|
|
|
|
let old_ranges_len = ranges.len();
|
|
|
|
ranges.retain(|r| r.contains(&value));
|
|
|
|
if ranges.len() != old_ranges_len {
|
|
state.set_dirty();
|
|
}
|
|
|
|
ranges.iter().for_each(|r| {
|
|
let b = &mut expressions[r.index()];
|
|
optimize_expr(&mut b.condition, state, false);
|
|
optimize_expr(&mut b.expr, state, false);
|
|
});
|
|
return;
|
|
}
|
|
}
|
|
|
|
// Promote the default case
|
|
state.set_dirty();
|
|
|
|
match def_case {
|
|
Some(index) => {
|
|
let mut def_stmt = Stmt::Expr(mem::take(&mut expressions[*index].expr).into());
|
|
optimize_stmt(&mut def_stmt, state, true);
|
|
*stmt = def_stmt;
|
|
}
|
|
_ => *stmt = StmtBlock::empty(*pos).into(),
|
|
}
|
|
}
|
|
// switch
|
|
Stmt::Switch(x, ..) => {
|
|
let (
|
|
match_expr,
|
|
SwitchCasesCollection {
|
|
expressions,
|
|
cases,
|
|
ranges,
|
|
def_case,
|
|
..
|
|
},
|
|
) = &mut **x;
|
|
|
|
optimize_expr(match_expr, state, false);
|
|
|
|
// Optimize blocks
|
|
expressions.iter_mut().for_each(|b| {
|
|
optimize_expr(&mut b.condition, state, false);
|
|
optimize_expr(&mut b.expr, state, false);
|
|
|
|
if b.is_always_false() && !b.expr.is_unit() {
|
|
b.expr = Expr::Unit(b.expr.position());
|
|
state.set_dirty();
|
|
}
|
|
});
|
|
|
|
// Remove false cases
|
|
cases.retain(|_, list| {
|
|
// Remove all entries that have false conditions
|
|
list.retain(|index| {
|
|
if expressions[*index].is_always_false() {
|
|
state.set_dirty();
|
|
false
|
|
} else {
|
|
true
|
|
}
|
|
});
|
|
// Remove all entries after a `true` condition
|
|
if let Some(n) = list
|
|
.iter()
|
|
.position(|&index| expressions[index].is_always_true())
|
|
{
|
|
if n + 1 < list.len() {
|
|
state.set_dirty();
|
|
list.truncate(n + 1);
|
|
}
|
|
}
|
|
// Remove if no entry left
|
|
if list.is_empty() {
|
|
state.set_dirty();
|
|
false
|
|
} else {
|
|
true
|
|
}
|
|
});
|
|
|
|
// Remove false ranges
|
|
ranges.retain(|r| {
|
|
if expressions[r.index()].is_always_false() {
|
|
state.set_dirty();
|
|
false
|
|
} else {
|
|
true
|
|
}
|
|
});
|
|
|
|
if let Some(index) = def_case {
|
|
optimize_expr(&mut expressions[*index].expr, state, false);
|
|
}
|
|
|
|
// Remove unused block statements
|
|
(0..expressions.len()).into_iter().for_each(|index| {
|
|
if *def_case == Some(index)
|
|
|| cases.values().flat_map(|c| c.iter()).any(|&n| n == index)
|
|
|| ranges.iter().any(|r| r.index() == index)
|
|
{
|
|
return;
|
|
}
|
|
|
|
let b = &mut expressions[index];
|
|
|
|
if !b.expr.is_unit() {
|
|
b.expr = Expr::Unit(b.expr.position());
|
|
state.set_dirty();
|
|
}
|
|
});
|
|
}
|
|
|
|
// while false { block } -> Noop
|
|
Stmt::While(x, ..) if matches!(x.expr, Expr::BoolConstant(false, ..)) => match x.expr {
|
|
Expr::BoolConstant(false, pos) => {
|
|
state.set_dirty();
|
|
*stmt = Stmt::Noop(pos);
|
|
}
|
|
_ => unreachable!("`Expr::BoolConstant"),
|
|
},
|
|
// while expr { block }
|
|
Stmt::While(x, ..) => {
|
|
let FlowControl { expr, body, .. } = &mut **x;
|
|
optimize_expr(expr, state, false);
|
|
if let Expr::BoolConstant(true, pos) = expr {
|
|
*expr = Expr::Unit(*pos);
|
|
}
|
|
**body = optimize_stmt_block(mem::take(&mut **body), state, false, true, false);
|
|
}
|
|
// do { block } while|until expr
|
|
Stmt::Do(x, ..) => {
|
|
optimize_expr(&mut x.expr, state, false);
|
|
*x.body = optimize_stmt_block(mem::take(&mut *x.body), state, false, true, false);
|
|
}
|
|
// for id in expr { block }
|
|
Stmt::For(x, ..) => {
|
|
optimize_expr(&mut x.2.expr, state, false);
|
|
*x.2.body = optimize_stmt_block(mem::take(&mut *x.2.body), state, false, true, false);
|
|
}
|
|
// let id = expr;
|
|
Stmt::Var(x, options, ..) if !options.contains(ASTFlags::CONSTANT) => {
|
|
optimize_expr(&mut x.1, state, false);
|
|
}
|
|
// import expr as var;
|
|
#[cfg(not(feature = "no_module"))]
|
|
Stmt::Import(x, ..) => optimize_expr(&mut x.0, state, false),
|
|
// { block }
|
|
Stmt::Block(block) => {
|
|
let span = block.span();
|
|
let statements = block.take_statements().into_vec().into();
|
|
let mut block = optimize_stmt_block(statements, state, preserve_result, true, false);
|
|
|
|
match block.as_mut_slice() {
|
|
[] => {
|
|
state.set_dirty();
|
|
*stmt = Stmt::Noop(span.start());
|
|
}
|
|
// Only one statement which is not block-dependent - promote
|
|
[s] if !s.is_block_dependent() => {
|
|
state.set_dirty();
|
|
*stmt = mem::take(s);
|
|
}
|
|
_ => *stmt = (block, span).into(),
|
|
}
|
|
}
|
|
// try { pure try_block } catch ( var ) { catch_block } -> try_block
|
|
Stmt::TryCatch(x, ..) if x.body.iter().all(Stmt::is_pure) => {
|
|
// If try block is pure, there will never be any exceptions
|
|
state.set_dirty();
|
|
*stmt = (
|
|
optimize_stmt_block(mem::take(&mut *x.body), state, false, true, false),
|
|
x.body.span(),
|
|
)
|
|
.into();
|
|
}
|
|
// try { try_block } catch ( var ) { catch_block }
|
|
Stmt::TryCatch(x, ..) => {
|
|
*x.body = optimize_stmt_block(mem::take(&mut *x.body), state, false, true, false);
|
|
*x.branch = optimize_stmt_block(mem::take(&mut *x.branch), state, false, true, false);
|
|
}
|
|
|
|
// expr(stmt)
|
|
Stmt::Expr(expr) if matches!(**expr, Expr::Stmt(..)) => {
|
|
state.set_dirty();
|
|
match expr.as_mut() {
|
|
Expr::Stmt(block) if !block.is_empty() => {
|
|
let mut stmt_block = *mem::take(block);
|
|
*stmt_block =
|
|
optimize_stmt_block(mem::take(&mut *stmt_block), state, true, true, false);
|
|
*stmt = stmt_block.into();
|
|
}
|
|
Expr::Stmt(..) => *stmt = Stmt::Noop(expr.position()),
|
|
_ => unreachable!("`Expr::Stmt`"),
|
|
}
|
|
}
|
|
|
|
Stmt::Expr(expr) => {
|
|
optimize_expr(expr, state, false);
|
|
|
|
// Do not promote until the expression is fully optimized
|
|
if !state.is_dirty() && matches!(**expr, Expr::FnCall(..) | Expr::Stmt(..)) {
|
|
*stmt = match *mem::take(expr) {
|
|
// func(...);
|
|
Expr::FnCall(x, pos) => Stmt::FnCall(x, pos),
|
|
// {};
|
|
Expr::Stmt(x) if x.is_empty() => Stmt::Noop(x.position()),
|
|
// {...};
|
|
Expr::Stmt(x) => (*x).into(),
|
|
_ => unreachable!(),
|
|
};
|
|
state.set_dirty();
|
|
}
|
|
}
|
|
|
|
// break expr;
|
|
Stmt::BreakLoop(Some(ref mut expr), ..) => optimize_expr(expr, state, false),
|
|
|
|
// return expr;
|
|
Stmt::Return(Some(ref mut expr), ..) => optimize_expr(expr, state, false),
|
|
|
|
// All other statements - skip
|
|
_ => (),
|
|
}
|
|
}
|
|
|
|
/// Optimize an [expression][Expr].
|
|
fn optimize_expr(expr: &mut Expr, state: &mut OptimizerState, _chaining: bool) {
|
|
// These keywords are handled specially
|
|
const DONT_EVAL_KEYWORDS: &[&str] = &[
|
|
KEYWORD_PRINT, // side effects
|
|
KEYWORD_DEBUG, // side effects
|
|
KEYWORD_EVAL, // arbitrary scripts
|
|
];
|
|
|
|
match expr {
|
|
// {}
|
|
Expr::Stmt(x) if x.is_empty() => { state.set_dirty(); *expr = Expr::Unit(x.position()) }
|
|
Expr::Stmt(x) if x.len() == 1 && matches!(x.statements()[0], Stmt::Expr(..)) => {
|
|
state.set_dirty();
|
|
match x.take_statements().remove(0) {
|
|
Stmt::Expr(mut e) => {
|
|
optimize_expr(&mut e, state, false);
|
|
*expr = *e;
|
|
}
|
|
_ => unreachable!("`Expr::Stmt`")
|
|
}
|
|
}
|
|
// { stmt; ... } - do not count promotion as dirty because it gets turned back into an array
|
|
Expr::Stmt(x) => {
|
|
***x = optimize_stmt_block(mem::take(&mut **x), state, true, true, false);
|
|
|
|
// { Stmt(Expr) } - promote
|
|
if let [ Stmt::Expr(e) ] = &mut ****x { state.set_dirty(); *expr = mem::take(e); }
|
|
}
|
|
// ()?.rhs
|
|
#[cfg(not(feature = "no_object"))]
|
|
Expr::Dot(x, options, ..) if options.contains(ASTFlags::NEGATED) && matches!(x.lhs, Expr::Unit(..)) => {
|
|
state.set_dirty();
|
|
*expr = mem::take(&mut x.lhs);
|
|
}
|
|
// lhs.rhs
|
|
#[cfg(not(feature = "no_object"))]
|
|
Expr::Dot(x, ..) if !_chaining => match (&mut x.lhs, &mut x.rhs) {
|
|
// map.string
|
|
(Expr::Map(m, pos), Expr::Property(p, ..)) if m.0.iter().all(|(.., x)| x.is_pure()) => {
|
|
let prop = p.2.as_str();
|
|
// Map literal where everything is pure - promote the indexed item.
|
|
// All other items can be thrown away.
|
|
state.set_dirty();
|
|
*expr = mem::take(&mut m.0).into_iter().find(|(x, ..)| x.as_str() == prop)
|
|
.map_or_else(|| Expr::Unit(*pos), |(.., mut expr)| { expr.set_position(*pos); expr });
|
|
}
|
|
// var.rhs
|
|
(Expr::Variable(..), rhs) => optimize_expr(rhs, state, true),
|
|
// const.type_of()
|
|
(lhs, Expr::MethodCall(x, pos)) if lhs.is_constant() && x.name == KEYWORD_TYPE_OF && x.args.is_empty() => {
|
|
if let Some(value) = lhs.get_literal_value() {
|
|
state.set_dirty();
|
|
let typ = state.engine.map_type_name(value.type_name()).into();
|
|
*expr = Expr::from_dynamic(typ, *pos);
|
|
}
|
|
}
|
|
// const.is_shared()
|
|
#[cfg(not(feature = "no_closure"))]
|
|
(lhs, Expr::MethodCall(x, pos)) if lhs.is_constant() && x.name == crate::engine::KEYWORD_IS_SHARED && x.args.is_empty() => {
|
|
if let Some(..) = lhs.get_literal_value() {
|
|
state.set_dirty();
|
|
*expr = Expr::from_dynamic(Dynamic::FALSE, *pos);
|
|
}
|
|
}
|
|
// lhs.rhs
|
|
(lhs, rhs) => { optimize_expr(lhs, state, false); optimize_expr(rhs, state, true); }
|
|
}
|
|
// ....lhs.rhs
|
|
#[cfg(not(feature = "no_object"))]
|
|
Expr::Dot(x,..) => { optimize_expr(&mut x.lhs, state, false); optimize_expr(&mut x.rhs, state, _chaining); }
|
|
|
|
// ()?[rhs]
|
|
#[cfg(not(feature = "no_index"))]
|
|
Expr::Index(x, options, ..) if options.contains(ASTFlags::NEGATED) && matches!(x.lhs, Expr::Unit(..)) => {
|
|
state.set_dirty();
|
|
*expr = mem::take(&mut x.lhs);
|
|
}
|
|
// lhs[rhs]
|
|
#[cfg(not(feature = "no_index"))]
|
|
#[allow(clippy::cast_sign_loss, clippy::cast_possible_truncation)]
|
|
Expr::Index(x, ..) if !_chaining => match (&mut x.lhs, &mut x.rhs) {
|
|
// array[int]
|
|
(Expr::Array(a, pos), Expr::IntegerConstant(i, ..)) if *i >= 0 && *i <= crate::MAX_USIZE_INT && (*i as usize) < a.len() && a.iter().all(Expr::is_pure) => {
|
|
// Array literal where everything is pure - promote the indexed item.
|
|
// All other items can be thrown away.
|
|
state.set_dirty();
|
|
let mut result = mem::take(&mut a[*i as usize]);
|
|
result.set_position(*pos);
|
|
*expr = result;
|
|
}
|
|
// array[-int]
|
|
(Expr::Array(a, pos), Expr::IntegerConstant(i, ..)) if *i < 0 && i.unsigned_abs() as u64 <= a.len() as u64 && a.iter().all(Expr::is_pure) => {
|
|
// Array literal where everything is pure - promote the indexed item.
|
|
// All other items can be thrown away.
|
|
state.set_dirty();
|
|
let index = a.len() - i.unsigned_abs() as usize;
|
|
let mut result = mem::take(&mut a[index]);
|
|
result.set_position(*pos);
|
|
*expr = result;
|
|
}
|
|
// map[string]
|
|
(Expr::Map(m, pos), Expr::StringConstant(s, ..)) if m.0.iter().all(|(.., x)| x.is_pure()) => {
|
|
// Map literal where everything is pure - promote the indexed item.
|
|
// All other items can be thrown away.
|
|
state.set_dirty();
|
|
*expr = mem::take(&mut m.0).into_iter().find(|(x, ..)| x.as_str() == s.as_str())
|
|
.map_or_else(|| Expr::Unit(*pos), |(.., mut expr)| { expr.set_position(*pos); expr });
|
|
}
|
|
// int[int]
|
|
(Expr::IntegerConstant(n, pos), Expr::IntegerConstant(i, ..)) if *i >= 0 && *i <= crate::MAX_USIZE_INT && (*i as usize) < crate::INT_BITS => {
|
|
// Bit-field literal indexing - get the bit
|
|
state.set_dirty();
|
|
*expr = Expr::BoolConstant((*n & (1 << (*i as usize))) != 0, *pos);
|
|
}
|
|
// int[-int]
|
|
(Expr::IntegerConstant(n, pos), Expr::IntegerConstant(i, ..)) if *i < 0 && i.unsigned_abs() as u64 <= crate::INT_BITS as u64 => {
|
|
// Bit-field literal indexing - get the bit
|
|
state.set_dirty();
|
|
*expr = Expr::BoolConstant((*n & (1 << (crate::INT_BITS - i.unsigned_abs() as usize))) != 0, *pos);
|
|
}
|
|
// string[int]
|
|
(Expr::StringConstant(s, pos), Expr::IntegerConstant(i, ..)) if *i >= 0 && *i <= crate::MAX_USIZE_INT && (*i as usize) < s.chars().count() => {
|
|
// String literal indexing - get the character
|
|
state.set_dirty();
|
|
*expr = Expr::CharConstant(s.chars().nth(*i as usize).unwrap(), *pos);
|
|
}
|
|
// string[-int]
|
|
(Expr::StringConstant(s, pos), Expr::IntegerConstant(i, ..)) if *i < 0 && i.unsigned_abs() as u64 <= s.chars().count() as u64 => {
|
|
// String literal indexing - get the character
|
|
state.set_dirty();
|
|
*expr = Expr::CharConstant(s.chars().rev().nth(i.unsigned_abs() as usize - 1).unwrap(), *pos);
|
|
}
|
|
// var[rhs]
|
|
(Expr::Variable(..), rhs) => optimize_expr(rhs, state, true),
|
|
// lhs[rhs]
|
|
(lhs, rhs) => { optimize_expr(lhs, state, false); optimize_expr(rhs, state, true); }
|
|
},
|
|
// ...[lhs][rhs]
|
|
#[cfg(not(feature = "no_index"))]
|
|
Expr::Index(x, ..) => { optimize_expr(&mut x.lhs, state, false); optimize_expr(&mut x.rhs, state, _chaining); }
|
|
// ``
|
|
Expr::InterpolatedString(x, pos) if x.is_empty() => {
|
|
state.set_dirty();
|
|
*expr = Expr::StringConstant(state.engine.const_empty_string(), *pos);
|
|
}
|
|
// `... ${const} ...`
|
|
Expr::InterpolatedString(..) if expr.is_constant() => {
|
|
state.set_dirty();
|
|
*expr = Expr::StringConstant(expr.get_literal_value().unwrap().cast::<ImmutableString>(), expr.position());
|
|
}
|
|
// `... ${ ... } ...`
|
|
Expr::InterpolatedString(x, ..) => {
|
|
x.iter_mut().for_each(|expr| optimize_expr(expr, state, false));
|
|
|
|
let mut n = 0;
|
|
|
|
// Merge consecutive strings
|
|
while n < x.len() - 1 {
|
|
match (mem::take(&mut x[n]), mem::take(&mut x[n+1])) {
|
|
(Expr::StringConstant(mut s1, pos), Expr::StringConstant(s2, ..)) => { s1 += s2; x[n] = Expr::StringConstant(s1, pos); x.remove(n+1); state.set_dirty(); }
|
|
(expr1, Expr::Unit(..)) => { x[n] = expr1; x.remove(n+1); state.set_dirty(); }
|
|
(Expr::Unit(..), expr2) => { x[n+1] = expr2; x.remove(n); state.set_dirty(); }
|
|
(expr1, Expr::StringConstant(s, ..)) if s.is_empty() => { x[n] = expr1; x.remove(n+1); state.set_dirty(); }
|
|
(Expr::StringConstant(s, ..), expr2) if s.is_empty()=> { x[n+1] = expr2; x.remove(n); state.set_dirty(); }
|
|
(expr1, expr2) => { x[n] = expr1; x[n+1] = expr2; n += 1; }
|
|
}
|
|
}
|
|
|
|
x.shrink_to_fit();
|
|
}
|
|
// [ constant .. ]
|
|
#[cfg(not(feature = "no_index"))]
|
|
Expr::Array(..) if expr.is_constant() => {
|
|
state.set_dirty();
|
|
*expr = Expr::DynamicConstant(expr.get_literal_value().unwrap().into(), expr.position());
|
|
}
|
|
// [ items .. ]
|
|
#[cfg(not(feature = "no_index"))]
|
|
Expr::Array(x, ..) => x.iter_mut().for_each(|expr| optimize_expr(expr, state, false)),
|
|
// #{ key:constant, .. }
|
|
#[cfg(not(feature = "no_object"))]
|
|
Expr::Map(..) if expr.is_constant() => {
|
|
state.set_dirty();
|
|
*expr = Expr::DynamicConstant(expr.get_literal_value().unwrap().into(), expr.position());
|
|
}
|
|
// #{ key:value, .. }
|
|
#[cfg(not(feature = "no_object"))]
|
|
Expr::Map(x, ..) => x.0.iter_mut().for_each(|(.., expr)| optimize_expr(expr, state, false)),
|
|
// lhs && rhs
|
|
Expr::And(x, ..) => match (&mut x.lhs, &mut x.rhs) {
|
|
// true && rhs -> rhs
|
|
(Expr::BoolConstant(true, ..), rhs) => { state.set_dirty(); optimize_expr(rhs, state, false); *expr = mem::take(rhs); }
|
|
// false && rhs -> false
|
|
(Expr::BoolConstant(false, pos), ..) => { state.set_dirty(); *expr = Expr::BoolConstant(false, *pos); }
|
|
// lhs && true -> lhs
|
|
(lhs, Expr::BoolConstant(true, ..)) => { state.set_dirty(); optimize_expr(lhs, state, false); *expr = mem::take(lhs); }
|
|
// lhs && rhs
|
|
(lhs, rhs) => { optimize_expr(lhs, state, false); optimize_expr(rhs, state, false); }
|
|
},
|
|
// lhs || rhs
|
|
Expr::Or(ref mut x, ..) => match (&mut x.lhs, &mut x.rhs) {
|
|
// false || rhs -> rhs
|
|
(Expr::BoolConstant(false, ..), rhs) => { state.set_dirty(); optimize_expr(rhs, state, false); *expr = mem::take(rhs); }
|
|
// true || rhs -> true
|
|
(Expr::BoolConstant(true, pos), ..) => { state.set_dirty(); *expr = Expr::BoolConstant(true, *pos); }
|
|
// lhs || false
|
|
(lhs, Expr::BoolConstant(false, ..)) => { state.set_dirty(); optimize_expr(lhs, state, false); *expr = mem::take(lhs); }
|
|
// lhs || rhs
|
|
(lhs, rhs) => { optimize_expr(lhs, state, false); optimize_expr(rhs, state, false); }
|
|
},
|
|
// () ?? rhs -> rhs
|
|
Expr::Coalesce(x, ..) if matches!(x.lhs, Expr::Unit(..)) => {
|
|
state.set_dirty();
|
|
*expr = mem::take(&mut x.rhs);
|
|
},
|
|
// lhs:constant ?? rhs -> lhs
|
|
Expr::Coalesce(x, ..) if x.lhs.is_constant() => {
|
|
state.set_dirty();
|
|
*expr = mem::take(&mut x.lhs);
|
|
},
|
|
|
|
// !true or !false
|
|
Expr::FnCall(x,..)
|
|
if x.name == OP_NOT
|
|
&& x.args.len() == 1
|
|
&& matches!(x.args[0], Expr::BoolConstant(..))
|
|
=> {
|
|
state.set_dirty();
|
|
if let Expr::BoolConstant(b, pos) = x.args[0] {
|
|
*expr = Expr::BoolConstant(!b, pos)
|
|
} else {
|
|
unreachable!()
|
|
}
|
|
}
|
|
|
|
// eval!
|
|
Expr::FnCall(x, ..) if x.name == KEYWORD_EVAL => {
|
|
state.propagate_constants = false;
|
|
}
|
|
// Fn
|
|
Expr::FnCall(x, pos)
|
|
if !x.is_qualified() // Non-qualified
|
|
&& state.optimization_level == OptimizationLevel::Simple // simple optimizations
|
|
&& x.args.len() == 1
|
|
&& x.name == KEYWORD_FN_PTR
|
|
&& x.constant_args()
|
|
=> {
|
|
let fn_name = match x.args[0] {
|
|
Expr::StringConstant(ref s, ..) => s.clone().into(),
|
|
_ => Dynamic::UNIT
|
|
};
|
|
|
|
if let Ok(fn_ptr) = fn_name.into_immutable_string().map_err(Into::into).and_then(FnPtr::try_from) {
|
|
state.set_dirty();
|
|
*expr = Expr::DynamicConstant(Box::new(fn_ptr.into()), *pos);
|
|
} else {
|
|
optimize_expr(&mut x.args[0], state, false);
|
|
}
|
|
}
|
|
|
|
// Do not call some special keywords
|
|
Expr::FnCall(x, ..) if DONT_EVAL_KEYWORDS.contains(&x.name.as_str()) => {
|
|
x.args.iter_mut().for_each(|a| optimize_expr(a, state, false));
|
|
}
|
|
|
|
// Call built-in operators
|
|
Expr::FnCall(x, pos)
|
|
if !x.is_qualified() // Non-qualified
|
|
&& state.optimization_level == OptimizationLevel::Simple // simple optimizations
|
|
&& x.constant_args() // all arguments are constants
|
|
=> {
|
|
let arg_values = &mut x.args.iter().map(|e| e.get_literal_value().unwrap()).collect::<StaticVec<_>>();
|
|
let arg_types: StaticVec<_> = arg_values.iter().map(Dynamic::type_id).collect();
|
|
|
|
match x.name.as_str() {
|
|
KEYWORD_TYPE_OF if arg_values.len() == 1 => {
|
|
state.set_dirty();
|
|
let typ = state.engine.map_type_name(arg_values[0].type_name()).into();
|
|
*expr = Expr::from_dynamic(typ, *pos);
|
|
return;
|
|
}
|
|
#[cfg(not(feature = "no_closure"))]
|
|
crate::engine::KEYWORD_IS_SHARED if arg_values.len() == 1 => {
|
|
state.set_dirty();
|
|
*expr = Expr::from_dynamic(Dynamic::FALSE, *pos);
|
|
return;
|
|
}
|
|
// Overloaded operators can override built-in.
|
|
_ if x.args.len() == 2 && x.op_token.is_some() && (state.engine.fast_operators() || !state.engine.has_native_fn_override(x.hashes.native(), &arg_types)) => {
|
|
if let Some(result) = get_builtin_binary_op_fn(x.op_token.as_ref().unwrap(), &arg_values[0], &arg_values[1])
|
|
.and_then(|(f, ctx)| {
|
|
let context = ctx.then(|| (state.engine, x.name.as_str(), None, &state.global, *pos).into());
|
|
let (first, second) = arg_values.split_first_mut().unwrap();
|
|
f(context, &mut [ first, &mut second[0] ]).ok()
|
|
}) {
|
|
state.set_dirty();
|
|
*expr = Expr::from_dynamic(result, *pos);
|
|
return;
|
|
}
|
|
}
|
|
_ => ()
|
|
}
|
|
|
|
x.args.iter_mut().for_each(|a| optimize_expr(a, state, false));
|
|
|
|
// Move constant arguments
|
|
x.args.iter_mut().for_each(|arg| match arg {
|
|
Expr::DynamicConstant(..) | Expr::Unit(..)
|
|
| Expr::StringConstant(..) | Expr::CharConstant(..)
|
|
| Expr::BoolConstant(..) | Expr::IntegerConstant(..) => (),
|
|
|
|
#[cfg(not(feature = "no_float"))]
|
|
Expr:: FloatConstant(..) => (),
|
|
|
|
_ => if let Some(value) = arg.get_literal_value() {
|
|
state.set_dirty();
|
|
*arg = Expr::DynamicConstant(value.into(), arg.start_position());
|
|
},
|
|
});
|
|
}
|
|
|
|
// Eagerly call functions
|
|
Expr::FnCall(x, pos)
|
|
if !x.is_qualified() // non-qualified
|
|
&& state.optimization_level == OptimizationLevel::Full // full optimizations
|
|
&& x.constant_args() // all arguments are constants
|
|
=> {
|
|
// First search for script-defined functions (can override built-in)
|
|
#[cfg(not(feature = "no_function"))]
|
|
let has_script_fn = !x.hashes.is_native_only() && state.global.lib.iter().find_map(|m| m.get_script_fn(&x.name, x.args.len())).is_some();
|
|
#[cfg(feature = "no_function")]
|
|
let has_script_fn = false;
|
|
|
|
if !has_script_fn {
|
|
let arg_values = &mut x.args.iter().map(Expr::get_literal_value).collect::<Option<StaticVec<_>>>().unwrap();
|
|
|
|
let result = match x.name.as_str() {
|
|
KEYWORD_TYPE_OF if arg_values.len() == 1 => Some(state.engine.map_type_name(arg_values[0].type_name()).into()),
|
|
#[cfg(not(feature = "no_closure"))]
|
|
crate::engine::KEYWORD_IS_SHARED if arg_values.len() == 1 => Some(Dynamic::FALSE),
|
|
_ => state.call_fn_with_constant_arguments(&x.name, x.op_token.as_ref(), arg_values)
|
|
};
|
|
|
|
if let Some(r) = result {
|
|
state.set_dirty();
|
|
*expr = Expr::from_dynamic(r, *pos);
|
|
return;
|
|
}
|
|
}
|
|
|
|
x.args.iter_mut().for_each(|a| optimize_expr(a, state, false));
|
|
}
|
|
|
|
// id(args ..) or xxx.id(args ..) -> optimize function call arguments
|
|
Expr::FnCall(x, ..) | Expr::MethodCall(x, ..) => x.args.iter_mut().for_each(|arg| {
|
|
optimize_expr(arg, state, false);
|
|
|
|
// Move constant arguments
|
|
match arg {
|
|
Expr::DynamicConstant(..) | Expr::Unit(..)
|
|
| Expr::StringConstant(..) | Expr::CharConstant(..)
|
|
| Expr::BoolConstant(..) | Expr::IntegerConstant(..) => (),
|
|
|
|
#[cfg(not(feature = "no_float"))]
|
|
Expr:: FloatConstant(..) => (),
|
|
|
|
_ => if let Some(value) = arg.get_literal_value() {
|
|
state.set_dirty();
|
|
*arg = Expr::DynamicConstant(value.into(), arg.start_position());
|
|
},
|
|
}
|
|
}),
|
|
|
|
// constant-name
|
|
#[cfg(not(feature = "no_module"))]
|
|
Expr::Variable(x, ..) if !x.1.is_empty() => (),
|
|
Expr::Variable(x, .., pos) if state.find_constant(&x.3).is_some() => {
|
|
// Replace constant with value
|
|
*expr = Expr::from_dynamic(state.find_constant(&x.3).unwrap().clone(), *pos);
|
|
state.set_dirty();
|
|
}
|
|
|
|
// Custom syntax
|
|
#[cfg(not(feature = "no_custom_syntax"))]
|
|
Expr::Custom(x, ..) => {
|
|
if x.scope_may_be_changed {
|
|
state.propagate_constants = false;
|
|
}
|
|
// Do not optimize custom syntax expressions as you won't know how they would be called
|
|
}
|
|
|
|
// All other expressions - skip
|
|
_ => (),
|
|
}
|
|
}
|
|
|
|
impl Engine {
|
|
/// Has a system function a Rust-native override?
|
|
fn has_native_fn_override(&self, hash_script: u64, arg_types: impl AsRef<[TypeId]>) -> bool {
|
|
let hash = calc_fn_hash_full(hash_script, arg_types.as_ref().iter().copied());
|
|
|
|
// First check the global namespace and packages, but skip modules that are standard because
|
|
// they should never conflict with system functions.
|
|
if self
|
|
.global_modules
|
|
.iter()
|
|
.filter(|m| !m.flags.contains(ModuleFlags::STANDARD_LIB))
|
|
.any(|m| m.contains_fn(hash))
|
|
{
|
|
return true;
|
|
}
|
|
|
|
// Then check sub-modules
|
|
#[cfg(not(feature = "no_module"))]
|
|
if self
|
|
.global_sub_modules
|
|
.as_ref()
|
|
.into_iter()
|
|
.flatten()
|
|
.any(|(_, m)| m.contains_qualified_fn(hash))
|
|
{
|
|
return true;
|
|
}
|
|
|
|
false
|
|
}
|
|
|
|
/// Optimize a block of [statements][Stmt] at top level.
|
|
///
|
|
/// Constants and variables from the scope are added.
|
|
fn optimize_top_level(
|
|
&self,
|
|
statements: StmtBlockContainer,
|
|
scope: Option<&Scope>,
|
|
lib: &[crate::SharedModule],
|
|
optimization_level: OptimizationLevel,
|
|
) -> StmtBlockContainer {
|
|
let mut statements = statements;
|
|
|
|
// If optimization level is None then skip optimizing
|
|
if optimization_level == OptimizationLevel::None {
|
|
statements.shrink_to_fit();
|
|
return statements;
|
|
}
|
|
|
|
// Set up the state
|
|
let mut state = OptimizerState::new(self, lib, optimization_level);
|
|
|
|
// Add constants from global modules
|
|
self.global_modules
|
|
.iter()
|
|
.rev()
|
|
.flat_map(|m| m.iter_var())
|
|
.for_each(|(name, value)| {
|
|
state.push_var(name, AccessMode::ReadOnly, Some(value.clone()))
|
|
});
|
|
|
|
// Add constants and variables from the scope
|
|
scope
|
|
.into_iter()
|
|
.flat_map(Scope::iter)
|
|
.for_each(|(name, constant, value)| {
|
|
if constant {
|
|
state.push_var(name, AccessMode::ReadOnly, Some(value));
|
|
} else {
|
|
state.push_var(name, AccessMode::ReadWrite, None);
|
|
}
|
|
});
|
|
|
|
optimize_stmt_block(statements, &mut state, true, false, true)
|
|
}
|
|
|
|
/// Optimize a collection of statements and functions into an [`AST`].
|
|
pub(crate) fn optimize_into_ast(
|
|
&self,
|
|
scope: Option<&Scope>,
|
|
statements: StmtBlockContainer,
|
|
#[cfg(not(feature = "no_function"))] functions: StaticVec<
|
|
crate::Shared<crate::ast::ScriptFnDef>,
|
|
>,
|
|
optimization_level: OptimizationLevel,
|
|
) -> AST {
|
|
let mut statements = statements;
|
|
|
|
#[cfg(not(feature = "no_function"))]
|
|
let lib: crate::Shared<_> = {
|
|
let mut module = crate::Module::new();
|
|
|
|
if optimization_level == OptimizationLevel::None {
|
|
functions.into_iter().for_each(|fn_def| {
|
|
module.set_script_fn(fn_def);
|
|
});
|
|
} else {
|
|
// We only need the script library's signatures for optimization purposes
|
|
let mut lib2 = crate::Module::new();
|
|
|
|
functions
|
|
.iter()
|
|
.map(|fn_def| crate::ast::ScriptFnDef {
|
|
name: fn_def.name.clone(),
|
|
access: fn_def.access,
|
|
body: crate::ast::StmtBlock::NONE,
|
|
#[cfg(not(feature = "no_object"))]
|
|
this_type: fn_def.this_type.clone(),
|
|
params: fn_def.params.clone(),
|
|
#[cfg(feature = "metadata")]
|
|
comments: Box::default(),
|
|
})
|
|
.for_each(|script_def| {
|
|
lib2.set_script_fn(script_def);
|
|
});
|
|
|
|
let lib2 = &[lib2.into()];
|
|
|
|
functions.into_iter().for_each(|fn_def| {
|
|
let mut fn_def = crate::func::shared_take_or_clone(fn_def);
|
|
|
|
// Optimize the function body
|
|
let body = mem::take(&mut *fn_def.body);
|
|
|
|
*fn_def.body = self.optimize_top_level(body, scope, lib2, optimization_level);
|
|
|
|
module.set_script_fn(fn_def);
|
|
});
|
|
}
|
|
|
|
module.into()
|
|
};
|
|
#[cfg(feature = "no_function")]
|
|
let lib: crate::Shared<_> = crate::Module::new().into();
|
|
|
|
statements.shrink_to_fit();
|
|
|
|
AST::new(
|
|
match optimization_level {
|
|
OptimizationLevel::None => statements,
|
|
OptimizationLevel::Simple | OptimizationLevel::Full => {
|
|
self.optimize_top_level(statements, scope, &[lib.clone()], optimization_level)
|
|
}
|
|
},
|
|
#[cfg(not(feature = "no_function"))]
|
|
lib,
|
|
)
|
|
}
|
|
}
|