refactor(minifier): fuse DCE AST passes (#8058)

oxc-project · Dec 21, 2024 · 77d845a · 77d845a
1 parent be2c60d
commit 77d845a
Show file tree

Hide file tree

Showing 2 changed files with 52 additions and 9 deletions.
diff --git a/crates/oxc_minifier/src/ast_passes/mod.rs b/crates/oxc_minifier/src/ast_passes/mod.rs
@@ -22,6 +22,8 @@ pub use peephole_substitute_alternate_syntax::PeepholeSubstituteAlternateSyntax;
 pub use remove_syntax::RemoveSyntax;
 pub use statement_fusion::StatementFusion;
 
+use crate::CompressOptions;
+
 pub trait CompressorPass<'a>: Traverse<'a> {
     fn build(&mut self, program: &mut Program<'a>, ctx: &mut ReusableTraverseCtx<'a>);
 }
@@ -287,3 +289,49 @@ impl<'a> Traverse<'a> for PeepholeOptimizations {
         self.x3_peephole_substitute_alternate_syntax.enter_binary_expression(expr, ctx);
     }
 }
+
+pub struct DeadCodeElimination {
+    x0_remove_syntax: RemoveSyntax,
+    x1_peephole_fold_constants: PeepholeFoldConstants,
+    x2_peephole_remove_dead_code: PeepholeRemoveDeadCode,
+}
+
+impl DeadCodeElimination {
+    pub fn new() -> Self {
+        Self {
+            x0_remove_syntax: RemoveSyntax::new(CompressOptions::all_false()),
+            x1_peephole_fold_constants: PeepholeFoldConstants::new(),
+            x2_peephole_remove_dead_code: PeepholeRemoveDeadCode::new(),
+        }
+    }
+}
+
+impl<'a> CompressorPass<'a> for DeadCodeElimination {
+    fn build(&mut self, program: &mut Program<'a>, ctx: &mut ReusableTraverseCtx<'a>) {
+        traverse_mut_with_ctx(self, program, ctx);
+    }
+}
+
+impl<'a> Traverse<'a> for DeadCodeElimination {
+    fn enter_statement(&mut self, stmt: &mut Statement<'a>, ctx: &mut TraverseCtx<'a>) {
+        self.x2_peephole_remove_dead_code.enter_statement(stmt, ctx);
+    }
+
+    fn exit_statement(&mut self, stmt: &mut Statement<'a>, ctx: &mut TraverseCtx<'a>) {
+        self.x2_peephole_remove_dead_code.exit_statement(stmt, ctx);
+    }
+
+    fn exit_program(&mut self, program: &mut Program<'a>, ctx: &mut TraverseCtx<'a>) {
+        self.x2_peephole_remove_dead_code.exit_program(program, ctx);
+    }
+
+    fn exit_statements(&mut self, stmts: &mut Vec<'a, Statement<'a>>, ctx: &mut TraverseCtx<'a>) {
+        self.x2_peephole_remove_dead_code.exit_statements(stmts, ctx);
+    }
+
+    fn exit_expression(&mut self, expr: &mut Expression<'a>, ctx: &mut TraverseCtx<'a>) {
+        self.x0_remove_syntax.exit_expression(expr, ctx);
+        self.x1_peephole_fold_constants.exit_expression(expr, ctx);
+        self.x2_peephole_remove_dead_code.exit_expression(expr, ctx);
+    }
+}
diff --git a/crates/oxc_minifier/src/compressor.rs b/crates/oxc_minifier/src/compressor.rs
@@ -5,8 +5,8 @@ use oxc_traverse::ReusableTraverseCtx;
 
 use crate::{
     ast_passes::{
-        CollapsePass, LatePeepholeOptimizations, PeepholeFoldConstants, PeepholeOptimizations,
-        PeepholeRemoveDeadCode, RemoveSyntax,
+        CollapsePass, DeadCodeElimination, LatePeepholeOptimizations, PeepholeOptimizations,
+        RemoveSyntax,
     },
     CompressOptions, CompressorPass,
 };
@@ -44,10 +44,7 @@ impl<'a> Compressor<'a> {
     pub fn dead_code_elimination(self, program: &mut Program<'a>) {
         let (symbols, scopes) =
             SemanticBuilder::new().build(program).semantic.into_symbol_table_and_scope_tree();
-        let mut ctx = ReusableTraverseCtx::new(scopes, symbols, self.allocator);
-        RemoveSyntax::new(self.options).build(program, &mut ctx);
-        PeepholeFoldConstants::new().build(program, &mut ctx);
-        PeepholeRemoveDeadCode::new().build(program, &mut ctx);
+        self.dead_code_elimination_with_symbols_and_scopes(symbols, scopes, program);
     }
 
     pub fn dead_code_elimination_with_symbols_and_scopes(
@@ -57,8 +54,6 @@ impl<'a> Compressor<'a> {
         program: &mut Program<'a>,
     ) {
         let mut ctx = ReusableTraverseCtx::new(scopes, symbols, self.allocator);
-        RemoveSyntax::new(self.options).build(program, &mut ctx);
-        PeepholeFoldConstants::new().build(program, &mut ctx);
-        PeepholeRemoveDeadCode::new().build(program, &mut ctx);
+        DeadCodeElimination::new().build(program, &mut ctx);
     }
 }