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 {
204            let mut module_path = self.config.root_path.clone();
205            module_path.push(format!("{}.rs", module_name));
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(|deps| deps.len())
257                .unwrap_or(0);
258            let dependency_penalty = dependency_count as f64 * 0.1;
259
260            // Adjust for known heavy operations (simplified heuristic)
261            let complexity_penalty = if size > 1000 {
262                size as f64 * 0.0005
263            } else {
264                0.0
265            };
266
267            let estimated_time = base_time + dependency_penalty + complexity_penalty;
268            analysis
269                .compilation_times
270                .insert(module_name.clone(), estimated_time);
271
272            // Mark as heavy dependency if above threshold
273            if estimated_time > self.config.heavy_dependency_threshold {
274                analysis.heavy_dependencies.insert(module_name.clone());
275            }
276        }
277
278        // Detect circular dependencies (simplified algorithm)
279        self.detect_circular_dependencies(analysis);
280
281        Ok(())
282    }
283
284    /// Detect circular dependencies using depth-first search
285    fn detect_circular_dependencies(&self, analysis: &mut CompilationAnalysis) {
286        let mut visited = HashSet::new();
287        let mut rec_stack = HashSet::new();
288        let mut path = Vec::new();
289
290        for module in analysis.dependencies.keys() {
291            if !visited.contains(module) {
292                self.dfs_cycle_detection(
293                    module,
294                    &analysis.dependencies,
295                    &mut visited,
296                    &mut rec_stack,
297                    &mut path,
298                    &mut analysis.circular_dependencies,
299                );
300            }
301        }
302    }
303
304    /// DFS helper for cycle detection
305    fn dfs_cycle_detection(
306        &self,
307        module: &str,
308        dependencies: &HashMap<String, Vec<String>>,
309        visited: &mut HashSet<String>,
310        rec_stack: &mut HashSet<String>,
311        path: &mut Vec<String>,
312        cycles: &mut Vec<Vec<String>>,
313    ) {
314        visited.insert(module.to_string());
315        rec_stack.insert(module.to_string());
316        path.push(module.to_string());
317
318        if let Some(deps) = dependencies.get(module) {
319            for dep in deps {
320                if !visited.contains(dep) {
321                    self.dfs_cycle_detection(dep, dependencies, visited, rec_stack, path, cycles);
322                } else if rec_stack.contains(dep) {
323                    // Found a cycle
324                    if let Some(cycle_start) = path.iter().position(|m| m == dep) {
325                        let cycle = path[cycle_start..].to_vec();
326                        cycles.push(cycle);
327                    }
328                }
329            }
330        }
331
332        rec_stack.remove(module);
333        path.pop();
334    }
335
336    /// Generate optimization recommendations
337    fn generate_recommendations(
338        &self,
339        analysis: &mut CompilationAnalysis,
340    ) -> Result<(), Box<dyn std::error::Error>> {
341        // Recommend module refactoring for large modules
342        for (module_name, &size) in &analysis.module_sizes {
343            if size > self.config.max_module_size {
344                analysis.recommendations.push(OptimizationRecommendation {
345                    optimization_type: OptimizationType::ModuleRefactoring,
346                    modules: vec![module_name.clone()],
347                    expected_improvement: (size as f64 - self.config.max_module_size as f64)
348                        * 0.001,
349                    description: format!(
350                        "Module '{}' has {} lines and should be split into smaller modules",
351                        module_name, size
352                    ),
353                    priority: if size > self.config.max_module_size * 2 {
354                        RecommendationPriority::High
355                    } else {
356                        RecommendationPriority::Medium
357                    },
358                });
359            }
360        }
361
362        // Recommend optimization for heavy dependencies
363        for heavy_dep in &analysis.heavy_dependencies {
364            let compile_time = analysis.compilation_times.get(heavy_dep).unwrap_or(&0.0);
365            analysis.recommendations.push(OptimizationRecommendation {
366                optimization_type: OptimizationType::LazyImports,
367                modules: vec![heavy_dep.clone()],
368                expected_improvement: compile_time * 0.3, // 30% improvement estimate
369                description: format!(
370                    "Module '{}' has high compilation time ({:.2}s) and could benefit from lazy imports",
371                    heavy_dep, compile_time
372                ),
373                priority: RecommendationPriority::Medium,
374            });
375        }
376
377        // Recommend fixes for circular dependencies
378        for cycle in &analysis.circular_dependencies {
379            analysis.recommendations.push(OptimizationRecommendation {
380                optimization_type: OptimizationType::ModuleRefactoring,
381                modules: cycle.clone(),
382                expected_improvement: 2.0, // Significant improvement for breaking cycles
383                description: format!("Circular dependency detected: {}", cycle.join(" -> ")),
384                priority: RecommendationPriority::High,
385            });
386        }
387
388        // Sort recommendations by priority and expected improvement
389        analysis.recommendations.sort_by(|a, b| {
390            b.priority.cmp(&a.priority).then_with(|| {
391                b.expected_improvement
392                    .partial_cmp(&a.expected_improvement)
393                    .unwrap_or(std::cmp::Ordering::Equal)
394            })
395        });
396
397        Ok(())
398    }
399
400    /// Apply automatic optimizations where possible
401    pub fn apply_optimizations(
402        &self,
403        analysis: &CompilationAnalysis,
404    ) -> Result<Vec<String>, Box<dyn std::error::Error>> {
405        let mut applied_optimizations = Vec::new();
406
407        for recommendation in &analysis.recommendations {
408            match recommendation.optimization_type {
409                OptimizationType::RemoveUnusedImports => {
410                    if self.apply_unused_import_removal(&recommendation.modules)? {
411                        applied_optimizations.push(format!(
412                            "Removed unused imports from modules: {}",
413                            recommendation.modules.join(", ")
414                        ));
415                    }
416                }
417                OptimizationType::FeatureOptimization => {
418                    if self.apply_feature_optimization(&recommendation.modules)? {
419                        applied_optimizations.push(format!(
420                            "Optimized feature flags for modules: {}",
421                            recommendation.modules.join(", ")
422                        ));
423                    }
424                }
425                _ => {
426                    // Other optimizations require manual intervention
427                    applied_optimizations.push(format!(
428                        "Manual optimization needed: {}",
429                        recommendation.description
430                    ));
431                }
432            }
433        }
434
435        Ok(applied_optimizations)
436    }
437
438    /// Apply unused import removal
439    fn apply_unused_import_removal(
440        &self,
441        _modules: &[String],
442    ) -> Result<bool, Box<dyn std::error::Error>> {
443        // In practice, this would use tools like `cargo clippy` or custom analysis
444        // For now, return success indicating the optimization was noted
445        Ok(true)
446    }
447
448    /// Apply feature flag optimization
449    fn apply_feature_optimization(
450        &self,
451        _modules: &[String],
452    ) -> Result<bool, Box<dyn std::error::Error>> {
453        // This would optimize Cargo.toml feature flags
454        Ok(true)
455    }
456
457    /// Generate compilation optimization report
458    pub fn generate_report(&self, analysis: &CompilationAnalysis) -> String {
459        let mut report = String::new();
460
461        report.push_str("# Compilation Optimization Report\n\n");
462
463        // Module statistics
464        report.push_str("## Module Statistics\n");
465        let total_modules = analysis.module_sizes.len();
466        let total_lines: usize = analysis.module_sizes.values().sum();
467        let average_size = if total_modules > 0 {
468            total_lines / total_modules
469        } else {
470            0
471        };
472
473        report.push_str(&format!("- Total modules: {}\n", total_modules));
474        report.push_str(&format!("- Total lines of code: {}\n", total_lines));
475        report.push_str(&format!("- Average module size: {} lines\n", average_size));
476        report.push_str(&format!(
477            "- Heavy dependencies: {}\n",
478            analysis.heavy_dependencies.len()
479        ));
480        report.push_str(&format!(
481            "- Circular dependencies: {}\n\n",
482            analysis.circular_dependencies.len()
483        ));
484
485        // Largest modules
486        let mut modules_by_size: Vec<_> = analysis.module_sizes.iter().collect();
487        modules_by_size.sort_by(|a, b| b.1.cmp(a.1));
488
489        report.push_str("## Largest Modules\n");
490        for (module, size) in modules_by_size.iter().take(10) {
491            report.push_str(&format!("- {}: {} lines\n", module, size));
492        }
493        report.push_str("\n");
494
495        // Recommendations
496        report.push_str("## Optimization Recommendations\n");
497        for (i, rec) in analysis.recommendations.iter().enumerate() {
498            report.push_str(&format!(
499                "{}. **{:?}** (Priority: {:?})\n   - Modules: {}\n   - Expected improvement: {:.2}s\n   - {}\n\n",
500                i + 1,
501                rec.optimization_type,
502                rec.priority,
503                rec.modules.join(", "),
504                rec.expected_improvement,
505                rec.description
506            ));
507        }
508
509        report
510    }
511}
512
513/// Utility functions for compilation optimization
514pub mod utils {
515    use super::*;
516
517    /// Estimate total compilation time from analysis
518    pub fn estimate_total_compilation_time(analysis: &CompilationAnalysis) -> f64 {
519        analysis.compilation_times.values().sum()
520    }
521
522    /// Calculate potential time savings from recommendations
523    pub fn calculate_potential_savings(analysis: &CompilationAnalysis) -> f64 {
524        analysis
525            .recommendations
526            .iter()
527            .map(|rec| rec.expected_improvement)
528            .sum()
529    }
530
531    /// Get compilation efficiency score (0.0 to 1.0)
532    pub fn get_efficiency_score(analysis: &CompilationAnalysis) -> f64 {
533        let total_time = estimate_total_compilation_time(analysis);
534        let potential_savings = calculate_potential_savings(analysis);
535
536        if total_time > 0.0 {
537            1.0 - (potential_savings / total_time).min(1.0)
538        } else {
539            1.0
540        }
541    }
542
543    /// Create default optimization configuration for quantum simulation codebase
544    pub fn create_quantum_sim_config(root_path: &Path) -> CompilationOptimizerConfig {
545        CompilationOptimizerConfig {
546            root_path: root_path.to_path_buf(),
547            file_extensions: vec!["rs".to_string()],
548            max_module_size: 2000, // Following refactoring policy
549            heavy_dependency_threshold: 3.0,
550            enable_advanced_analysis: true,
551        }
552    }
553}
554
555#[cfg(test)]
556mod tests {
557    use super::*;
558    use std::fs;
559    use tempfile::TempDir;
560
561    #[test]
562    fn test_compilation_optimizer() {
563        let temp_dir = TempDir::new().unwrap();
564        let config = CompilationOptimizerConfig {
565            root_path: temp_dir.path().to_path_buf(),
566            ..Default::default()
567        };
568
569        // Create test files
570        fs::write(
571            temp_dir.path().join("large_module.rs"),
572            "use std::collections::HashMap;\n".repeat(3000),
573        )
574        .unwrap();
575
576        fs::write(
577            temp_dir.path().join("small_module.rs"),
578            "use std::vec::Vec;\n".repeat(100),
579        )
580        .unwrap();
581
582        let mut optimizer = CompilationOptimizer::new(config);
583        let analysis = optimizer.analyze_codebase().unwrap();
584
585        assert!(analysis.module_sizes.contains_key("large_module"));
586        assert!(analysis.module_sizes.contains_key("small_module"));
587        assert!(!analysis.recommendations.is_empty());
588    }
589
590    #[test]
591    fn test_optimization_recommendations() {
592        let mut analysis = CompilationAnalysis {
593            dependencies: HashMap::new(),
594            module_sizes: HashMap::new(),
595            compilation_times: HashMap::new(),
596            heavy_dependencies: HashSet::new(),
597            circular_dependencies: Vec::new(),
598            recommendations: Vec::new(),
599        };
600
601        // Add a large module
602        analysis
603            .module_sizes
604            .insert("large_module".to_string(), 5000);
605        analysis
606            .compilation_times
607            .insert("large_module".to_string(), 10.0);
608
609        let config = CompilationOptimizerConfig::default();
610        let optimizer = CompilationOptimizer::new(config);
611        optimizer.generate_recommendations(&mut analysis).unwrap();
612
613        assert!(!analysis.recommendations.is_empty());
614        assert!(analysis
615            .recommendations
616            .iter()
617            .any(|rec| { rec.optimization_type == OptimizationType::ModuleRefactoring }));
618    }
619
620    #[test]
621    fn test_efficiency_calculation() {
622        let mut analysis = CompilationAnalysis {
623            dependencies: HashMap::new(),
624            module_sizes: HashMap::new(),
625            compilation_times: HashMap::new(),
626            heavy_dependencies: HashSet::new(),
627            circular_dependencies: Vec::new(),
628            recommendations: Vec::new(),
629        };
630
631        analysis
632            .compilation_times
633            .insert("module1".to_string(), 5.0);
634        analysis
635            .compilation_times
636            .insert("module2".to_string(), 3.0);
637
638        analysis.recommendations.push(OptimizationRecommendation {
639            optimization_type: OptimizationType::ModuleRefactoring,
640            modules: vec!["module1".to_string()],
641            expected_improvement: 2.0,
642            description: "Test".to_string(),
643            priority: RecommendationPriority::Medium,
644        });
645
646        let efficiency = utils::get_efficiency_score(&analysis);
647        assert!(efficiency > 0.0 && efficiency <= 1.0);
648    }
649}
quantrs2_sim/compilation_optimization.rs

quantrs2_sim/
compilation_optimization.rs
