Merge pull request #19 from Tcode-Motion/no-clones-optimizer-4831851234818099068

⚡ Bolt: Optimize PassManager to eliminate redundant `.clone()` allocations

Author: Tcode-Motion

.jules/bolt.md

@@ -1,4 +0,0 @@
-## 2024-01-20 - Lifetime Refactoring in Parser to Eliminate Token Cloning
-**Learning:** In the Rust parser (`compiler/parser/src/parser.rs`), methods like `advance()` and `previous()` originally returned a reference tied to `&mut self`. Because `Token` was still borrowing `self` mutably, the parser couldn't call methods like `self.parse_prefix` (which requires another `&mut self` borrow) without first calling `.clone()` on the token to drop the initial borrow.
-**Action:** By explicitly defining the return lifetime as `&'a Token` (tied to the lifetime of the underlying token slice `&'a [Token]`, rather than the `Parser` instance), the mutable borrow of `self` ends immediately. This elegantly satisfies the borrow checker while removing the overhead of cloning tokens throughout `expressions.rs` and `statements.rs`. Look for similar lifetime constraints elsewhere in the compiler that force unnecessary copies.
-

compiler/optimizer/src/pass_manager.rs

@@ -50,7 +50,7 @@ impl PassManager {
             let res = pass.run(module, &mut self.analyses);
             let duration = start.elapsed();
 
-            let mut pass_stats = res.stats.clone();
+            let mut pass_stats = res.stats;
             pass_stats.time_taken_ns = duration.as_nanos();
 
             self.stats.combine(&pass_stats);

compiler/optimizer/src/passes/dead_code.rs

@@ -19,7 +19,7 @@ impl OptimizationPass for DeadCode {
 
         for func in &mut module.functions {
             // Retrieve Use-Def analysis
-            let use_def = analyses.get_use_def(func).clone();
+            let use_def = analyses.get_use_def(func);
 
             for block in &mut func.blocks {
                 block.instructions.retain(|inst| {

compiler/optimizer/src/pipeline.rs

@@ -74,7 +74,7 @@ impl OptimizationPipeline {
         }
 
         if overall_changed {
-            OptimizationResult::changed(self.manager.stats.clone())
+            OptimizationResult::changed(self.manager.stats)
         } else {
             OptimizationResult::unchanged("pipeline")
         }