quantrs2_sim/
compilation_optimization.rs

1//! Compilation Time Optimization
2//!
3//! This module provides tools and strategies for optimizing Rust compilation times
4//! in large quantum simulation codebases through dependency analysis and optimization.
5
6use serde::{Deserialize, Serialize};
7use std::collections::{HashMap, HashSet};
8use std::path::{Path, PathBuf};
9
10/// Analysis of module dependencies and compilation characteristics
11#[derive(Debug, Clone, Serialize, Deserialize)]
12pub struct CompilationAnalysis {
13    /// Module dependency graph
14    pub dependencies: HashMap<String, Vec<String>>,
15    /// Module sizes (lines of code)
16    pub module_sizes: HashMap<String, usize>,
17    /// Estimated compilation times per module
18    pub compilation_times: HashMap<String, f64>,
19    /// Heavy dependencies (expensive to compile)
20    pub heavy_dependencies: HashSet<String>,
21    /// Circular dependencies detected
22    pub circular_dependencies: Vec<Vec<String>>,
23    /// Optimization recommendations
24    pub recommendations: Vec<OptimizationRecommendation>,
25}
26
27/// Compilation optimization recommendations
28#[derive(Debug, Clone, Serialize, Deserialize)]
29pub struct OptimizationRecommendation {
30    /// Type of optimization
31    pub optimization_type: OptimizationType,
32    /// Affected modules
33    pub modules: Vec<String>,
34    /// Expected improvement
35    pub expected_improvement: f64,
36    /// Description of the optimization
37    pub description: String,
38    /// Implementation priority
39    pub priority: RecommendationPriority,
40}
41
42/// Types of compilation optimizations
43#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
44pub enum OptimizationType {
45    /// Reduce unused imports
46    RemoveUnusedImports,
47    /// Split large modules
48    ModuleRefactoring,
49    /// Use lazy imports where possible
50    LazyImports,
51    /// Optimize feature flags
52    FeatureOptimization,
53    /// Reduce macro usage
54    MacroOptimization,
55    /// Use dynamic loading
56    DynamicLoading,
57    /// Parallel compilation
58    ParallelCompilation,
59    /// Incremental compilation improvements
60    IncrementalCompilation,
61}
62
63/// Priority levels for recommendations
64#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Serialize, Deserialize)]
65pub enum RecommendationPriority {
66    /// Low impact optimization
67    Low,
68    /// Medium impact optimization
69    Medium,
70    /// High impact optimization
71    High,
72    /// Critical optimization needed
73    Critical,
74}
75
76/// Configuration for compilation optimization analysis
77#[derive(Debug, Clone)]
78pub struct CompilationOptimizerConfig {
79    /// Root directory to analyze
80    pub root_path: PathBuf,
81    /// File extensions to analyze
82    pub file_extensions: Vec<String>,
83    /// Maximum module size before recommending split
84    pub max_module_size: usize,
85    /// Threshold for heavy dependencies (compilation time in seconds)
86    pub heavy_dependency_threshold: f64,
87    /// Enable advanced analysis features
88    pub enable_advanced_analysis: bool,
89}
90
91impl Default for CompilationOptimizerConfig {
92    fn default() -> Self {
93        Self {
94            root_path: PathBuf::from("."),
95            file_extensions: vec!["rs".to_string()],
96            max_module_size: 2000,
97            heavy_dependency_threshold: 5.0,
98            enable_advanced_analysis: true,
99        }
100    }
101}
102
103/// Compilation optimizer for analyzing and improving build times
104pub struct CompilationOptimizer {
105    /// Configuration
106    config: CompilationOptimizerConfig,
107    /// Analysis cache
108    analysis_cache: HashMap<String, CompilationAnalysis>,
109}
110
111impl CompilationOptimizer {
112    /// Create new compilation optimizer
113    pub fn new(config: CompilationOptimizerConfig) -> Self {
114        Self {
115            config,
116            analysis_cache: HashMap::new(),
117        }
118    }
119
120    /// Analyze codebase for compilation optimization opportunities
121    pub fn analyze_codebase(&mut self) -> Result<CompilationAnalysis, Box<dyn std::error::Error>> {
122        let mut analysis = CompilationAnalysis {
123            dependencies: HashMap::new(),
124            module_sizes: HashMap::new(),
125            compilation_times: HashMap::new(),
126            heavy_dependencies: HashSet::new(),
127            circular_dependencies: Vec::new(),
128            recommendations: Vec::new(),
129        };
130
131        // Analyze module structure
132        self.analyze_module_structure(&mut analysis)?;
133
134        // Analyze dependencies
135        self.analyze_dependencies(&mut analysis)?;
136
137        // Detect compilation bottlenecks
138        self.detect_compilation_bottlenecks(&mut analysis)?;
139
140        // Generate optimization recommendations
141        self.generate_recommendations(&mut analysis)?;
142
143        Ok(analysis)
144    }
145
146    /// Analyze module structure and sizes
147    fn analyze_module_structure(
148        &self,
149        analysis: &mut CompilationAnalysis,
150    ) -> Result<(), Box<dyn std::error::Error>> {
151        use std::fs;
152
153        fn visit_files(
154            dir: &Path,
155            extensions: &[String],
156            analysis: &mut CompilationAnalysis,
157        ) -> Result<(), Box<dyn std::error::Error>> {
158            if dir.is_dir() {
159                for entry in fs::read_dir(dir)? {
160                    let entry = entry?;
161                    let path = entry.path();
162
163                    if path.is_dir() {
164                        visit_files(&path, extensions, analysis)?;
165                    } else if let Some(ext) = path.extension() {
166                        if extensions.contains(&ext.to_string_lossy().to_string()) {
167                            let content = fs::read_to_string(&path)?;
168                            let line_count = content.lines().count();
169
170                            let module_name = path
171                                .file_stem()
172                                .unwrap_or_default()
173                                .to_string_lossy()
174                                .to_string();
175
176                            analysis.module_sizes.insert(module_name, line_count);
177                        }
178                    }
179                }
180            }
181            Ok(())
182        }
183
184        visit_files(
185            &self.config.root_path,
186            &self.config.file_extensions,
187            analysis,
188        )?;
189        Ok(())
190    }
191
192    /// Analyze module dependencies
193    fn analyze_dependencies(
194        &self,
195        analysis: &mut CompilationAnalysis,
196    ) -> Result<(), Box<dyn std::error::Error>> {
197        use regex::Regex;
198        use std::fs;
199
200        let use_regex = Regex::new(r"^use\s+([^;]+);").unwrap();
201        let mod_regex = Regex::new(r"^(?:pub\s+)?mod\s+(\w+)").unwrap();
202
203        for module_name in analysis.module_sizes.keys() {
204            let mut module_path = self.config.root_path.clone();
205            module_path.push(format!("{module_name}.rs"));
206
207            if let Ok(content) = fs::read_to_string(&module_path) {
208                let mut dependencies = Vec::new();
209
210                for line in content.lines() {
211                    let line = line.trim();
212
213                    // Extract use statements
214                    if let Some(captures) = use_regex.captures(line) {
215                        let use_path = captures.get(1).unwrap().as_str();
216                        // Extract the first component of the use path
217                        if let Some(first_component) = use_path.split("::").next() {
218                            if first_component.starts_with("crate::") {
219                                let module = first_component
220                                    .strip_prefix("crate::")
221                                    .unwrap_or(first_component);
222                                dependencies.push(module.to_string());
223                            }
224                        }
225                    }
226
227                    // Extract mod statements
228                    if let Some(captures) = mod_regex.captures(line) {
229                        let mod_name = captures.get(1).unwrap().as_str();
230                        dependencies.push(mod_name.to_string());
231                    }
232                }
233
234                analysis
235                    .dependencies
236                    .insert(module_name.clone(), dependencies);
237            }
238        }
239
240        Ok(())
241    }
242
243    /// Detect compilation bottlenecks
244    fn detect_compilation_bottlenecks(
245        &self,
246        analysis: &mut CompilationAnalysis,
247    ) -> Result<(), Box<dyn std::error::Error>> {
248        // Estimate compilation times based on module size and complexity
249        for (module_name, &size) in &analysis.module_sizes {
250            let base_time = size as f64 * 0.001; // 1ms per line baseline
251
252            // Adjust for dependencies
253            let dependency_count = analysis
254                .dependencies
255                .get(module_name)
256                .map_or(0, |deps| deps.len());
257            let dependency_penalty = dependency_count as f64 * 0.1;
258
259            // Adjust for known heavy operations (simplified heuristic)
260            let complexity_penalty = if size > 1000 {
261                size as f64 * 0.0005
262            } else {
263                0.0
264            };
265
266            let estimated_time = base_time + dependency_penalty + complexity_penalty;
267            analysis
268                .compilation_times
269                .insert(module_name.clone(), estimated_time);
270
271            // Mark as heavy dependency if above threshold
272            if estimated_time > self.config.heavy_dependency_threshold {
273                analysis.heavy_dependencies.insert(module_name.clone());
274            }
275        }
276
277        // Detect circular dependencies (simplified algorithm)
278        self.detect_circular_dependencies(analysis);
279
280        Ok(())
281    }
282
283    /// Detect circular dependencies using depth-first search
284    fn detect_circular_dependencies(&self, analysis: &mut CompilationAnalysis) {
285        let mut visited = HashSet::new();
286        let mut rec_stack = HashSet::new();
287        let mut path = Vec::new();
288
289        for module in analysis.dependencies.keys() {
290            if !visited.contains(module) {
291                self.dfs_cycle_detection(
292                    module,
293                    &analysis.dependencies,
294                    &mut visited,
295                    &mut rec_stack,
296                    &mut path,
297                    &mut analysis.circular_dependencies,
298                );
299            }
300        }
301    }
302
303    /// DFS helper for cycle detection
304    fn dfs_cycle_detection(
305        &self,
306        module: &str,
307        dependencies: &HashMap<String, Vec<String>>,
308        visited: &mut HashSet<String>,
309        rec_stack: &mut HashSet<String>,
310        path: &mut Vec<String>,
311        cycles: &mut Vec<Vec<String>>,
312    ) {
313        visited.insert(module.to_string());
314        rec_stack.insert(module.to_string());
315        path.push(module.to_string());
316
317        if let Some(deps) = dependencies.get(module) {
318            for dep in deps {
319                if !visited.contains(dep) {
320                    self.dfs_cycle_detection(dep, dependencies, visited, rec_stack, path, cycles);
321                } else if rec_stack.contains(dep) {
322                    // Found a cycle
323                    if let Some(cycle_start) = path.iter().position(|m| m == dep) {
324                        let cycle = path[cycle_start..].to_vec();
325                        cycles.push(cycle);
326                    }
327                }
328            }
329        }
330
331        rec_stack.remove(module);
332        path.pop();
333    }
334
335    /// Generate optimization recommendations
336    fn generate_recommendations(
337        &self,
338        analysis: &mut CompilationAnalysis,
339    ) -> Result<(), Box<dyn std::error::Error>> {
340        // Recommend module refactoring for large modules
341        for (module_name, &size) in &analysis.module_sizes {
342            if size > self.config.max_module_size {
343                analysis.recommendations.push(OptimizationRecommendation {
344                    optimization_type: OptimizationType::ModuleRefactoring,
345                    modules: vec![module_name.clone()],
346                    expected_improvement: (size as f64 - self.config.max_module_size as f64)
347                        * 0.001,
348                    description: format!(
349                        "Module '{module_name}' has {size} lines and should be split into smaller modules"
350                    ),
351                    priority: if size > self.config.max_module_size * 2 {
352                        RecommendationPriority::High
353                    } else {
354                        RecommendationPriority::Medium
355                    },
356                });
357            }
358        }
359
360        // Recommend optimization for heavy dependencies
361        for heavy_dep in &analysis.heavy_dependencies {
362            let compile_time = analysis.compilation_times.get(heavy_dep).unwrap_or(&0.0);
363            analysis.recommendations.push(OptimizationRecommendation {
364                optimization_type: OptimizationType::LazyImports,
365                modules: vec![heavy_dep.clone()],
366                expected_improvement: compile_time * 0.3, // 30% improvement estimate
367                description: format!(
368                    "Module '{heavy_dep}' has high compilation time ({compile_time:.2}s) and could benefit from lazy imports"
369                ),
370                priority: RecommendationPriority::Medium,
371            });
372        }
373
374        // Recommend fixes for circular dependencies
375        for cycle in &analysis.circular_dependencies {
376            analysis.recommendations.push(OptimizationRecommendation {
377                optimization_type: OptimizationType::ModuleRefactoring,
378                modules: cycle.clone(),
379                expected_improvement: 2.0, // Significant improvement for breaking cycles
380                description: format!("Circular dependency detected: {}", cycle.join(" -> ")),
381                priority: RecommendationPriority::High,
382            });
383        }
384
385        // Sort recommendations by priority and expected improvement
386        analysis.recommendations.sort_by(|a, b| {
387            b.priority.cmp(&a.priority).then_with(|| {
388                b.expected_improvement
389                    .partial_cmp(&a.expected_improvement)
390                    .unwrap_or(std::cmp::Ordering::Equal)
391            })
392        });
393
394        Ok(())
395    }
396
397    /// Apply automatic optimizations where possible
398    pub fn apply_optimizations(
399        &self,
400        analysis: &CompilationAnalysis,
401    ) -> Result<Vec<String>, Box<dyn std::error::Error>> {
402        let mut applied_optimizations = Vec::new();
403
404        for recommendation in &analysis.recommendations {
405            match recommendation.optimization_type {
406                OptimizationType::RemoveUnusedImports => {
407                    if self.apply_unused_import_removal(&recommendation.modules)? {
408                        applied_optimizations.push(format!(
409                            "Removed unused imports from modules: {}",
410                            recommendation.modules.join(", ")
411                        ));
412                    }
413                }
414                OptimizationType::FeatureOptimization => {
415                    if self.apply_feature_optimization(&recommendation.modules)? {
416                        applied_optimizations.push(format!(
417                            "Optimized feature flags for modules: {}",
418                            recommendation.modules.join(", ")
419                        ));
420                    }
421                }
422                _ => {
423                    // Other optimizations require manual intervention
424                    applied_optimizations.push(format!(
425                        "Manual optimization needed: {}",
426                        recommendation.description
427                    ));
428                }
429            }
430        }
431
432        Ok(applied_optimizations)
433    }
434
435    /// Apply unused import removal
436    fn apply_unused_import_removal(
437        &self,
438        _modules: &[String],
439    ) -> Result<bool, Box<dyn std::error::Error>> {
440        // In practice, this would use tools like `cargo clippy` or custom analysis
441        // For now, return success indicating the optimization was noted
442        Ok(true)
443    }
444
445    /// Apply feature flag optimization
446    fn apply_feature_optimization(
447        &self,
448        _modules: &[String],
449    ) -> Result<bool, Box<dyn std::error::Error>> {
450        // This would optimize Cargo.toml feature flags
451        Ok(true)
452    }
453
454    /// Generate compilation optimization report
455    pub fn generate_report(&self, analysis: &CompilationAnalysis) -> String {
456        let mut report = String::new();
457
458        report.push_str("# Compilation Optimization Report\n\n");
459
460        // Module statistics
461        report.push_str("## Module Statistics\n");
462        let total_modules = analysis.module_sizes.len();
463        let total_lines: usize = analysis.module_sizes.values().sum();
464        let average_size = if total_modules > 0 {
465            total_lines / total_modules
466        } else {
467            0
468        };
469
470        report.push_str(&format!("- Total modules: {total_modules}\n"));
471        report.push_str(&format!("- Total lines of code: {total_lines}\n"));
472        report.push_str(&format!("- Average module size: {average_size} lines\n"));
473        report.push_str(&format!(
474            "- Heavy dependencies: {}\n",
475            analysis.heavy_dependencies.len()
476        ));
477        report.push_str(&format!(
478            "- Circular dependencies: {}\n\n",
479            analysis.circular_dependencies.len()
480        ));
481
482        // Largest modules
483        let mut modules_by_size: Vec<_> = analysis.module_sizes.iter().collect();
484        modules_by_size.sort_by(|a, b| b.1.cmp(a.1));
485
486        report.push_str("## Largest Modules\n");
487        for (module, size) in modules_by_size.iter().take(10) {
488            report.push_str(&format!("- {module}: {size} lines\n"));
489        }
490        report.push('\n');
491
492        // Recommendations
493        report.push_str("## Optimization Recommendations\n");
494        for (i, rec) in analysis.recommendations.iter().enumerate() {
495            report.push_str(&format!(
496                "{}. **{:?}** (Priority: {:?})\n   - Modules: {}\n   - Expected improvement: {:.2}s\n   - {}\n\n",
497                i + 1,
498                rec.optimization_type,
499                rec.priority,
500                rec.modules.join(", "),
501                rec.expected_improvement,
502                rec.description
503            ));
504        }
505
506        report
507    }
508}
509
510/// Utility functions for compilation optimization
511pub mod utils {
512    use super::*;
513
514    /// Estimate total compilation time from analysis
515    pub fn estimate_total_compilation_time(analysis: &CompilationAnalysis) -> f64 {
516        analysis.compilation_times.values().sum()
517    }
518
519    /// Calculate potential time savings from recommendations
520    pub fn calculate_potential_savings(analysis: &CompilationAnalysis) -> f64 {
521        analysis
522            .recommendations
523            .iter()
524            .map(|rec| rec.expected_improvement)
525            .sum()
526    }
527
528    /// Get compilation efficiency score (0.0 to 1.0)
529    pub fn get_efficiency_score(analysis: &CompilationAnalysis) -> f64 {
530        let total_time = estimate_total_compilation_time(analysis);
531        let potential_savings = calculate_potential_savings(analysis);
532
533        if total_time > 0.0 {
534            1.0 - (potential_savings / total_time).min(1.0)
535        } else {
536            1.0
537        }
538    }
539
540    /// Create default optimization configuration for quantum simulation codebase
541    pub fn create_quantum_sim_config(root_path: &Path) -> CompilationOptimizerConfig {
542        CompilationOptimizerConfig {
543            root_path: root_path.to_path_buf(),
544            file_extensions: vec!["rs".to_string()],
545            max_module_size: 2000, // Following refactoring policy
546            heavy_dependency_threshold: 3.0,
547            enable_advanced_analysis: true,
548        }
549    }
550}
551
552#[cfg(test)]
553mod tests {
554    use super::*;
555    use std::fs;
556    use tempfile::TempDir;
557
558    #[test]
559    fn test_compilation_optimizer() {
560        let temp_dir = TempDir::new().unwrap();
561        let config = CompilationOptimizerConfig {
562            root_path: temp_dir.path().to_path_buf(),
563            ..Default::default()
564        };
565
566        // Create test files
567        fs::write(
568            temp_dir.path().join("large_module.rs"),
569            "use std::collections::HashMap;\n".repeat(3000),
570        )
571        .unwrap();
572
573        fs::write(
574            temp_dir.path().join("small_module.rs"),
575            "use std::vec::Vec;\n".repeat(100),
576        )
577        .unwrap();
578
579        let mut optimizer = CompilationOptimizer::new(config);
580        let analysis = optimizer.analyze_codebase().unwrap();
581
582        assert!(analysis.module_sizes.contains_key("large_module"));
583        assert!(analysis.module_sizes.contains_key("small_module"));
584        assert!(!analysis.recommendations.is_empty());
585    }
586
587    #[test]
588    fn test_optimization_recommendations() {
589        let mut analysis = CompilationAnalysis {
590            dependencies: HashMap::new(),
591            module_sizes: HashMap::new(),
592            compilation_times: HashMap::new(),
593            heavy_dependencies: HashSet::new(),
594            circular_dependencies: Vec::new(),
595            recommendations: Vec::new(),
596        };
597
598        // Add a large module
599        analysis
600            .module_sizes
601            .insert("large_module".to_string(), 5000);
602        analysis
603            .compilation_times
604            .insert("large_module".to_string(), 10.0);
605
606        let config = CompilationOptimizerConfig::default();
607        let optimizer = CompilationOptimizer::new(config);
608        optimizer.generate_recommendations(&mut analysis).unwrap();
609
610        assert!(!analysis.recommendations.is_empty());
611        assert!(analysis
612            .recommendations
613            .iter()
614            .any(|rec| { rec.optimization_type == OptimizationType::ModuleRefactoring }));
615    }
616
617    #[test]
618    fn test_efficiency_calculation() {
619        let mut analysis = CompilationAnalysis {
620            dependencies: HashMap::new(),
621            module_sizes: HashMap::new(),
622            compilation_times: HashMap::new(),
623            heavy_dependencies: HashSet::new(),
624            circular_dependencies: Vec::new(),
625            recommendations: Vec::new(),
626        };
627
628        analysis
629            .compilation_times
630            .insert("module1".to_string(), 5.0);
631        analysis
632            .compilation_times
633            .insert("module2".to_string(), 3.0);
634
635        analysis.recommendations.push(OptimizationRecommendation {
636            optimization_type: OptimizationType::ModuleRefactoring,
637            modules: vec!["module1".to_string()],
638            expected_improvement: 2.0,
639            description: "Test".to_string(),
640            priority: RecommendationPriority::Medium,
641        });
642
643        let efficiency = utils::get_efficiency_score(&analysis);
644        assert!(efficiency > 0.0 && efficiency <= 1.0);
645    }
646}
quantrs2_sim/compilation_optimization.rs

quantrs2_sim/
compilation_optimization.rs
