[LifetimeSafety] Enhance benchmark script for new sub analyses (#149577)
Enhanced the lifetime safety analysis benchmark script with more
detailed performance metrics and a new nested loop test case. This is a
worst case for loan expiry analysis.
### What changed?
- Added a new test case `nested_loops` that generates code with N levels
of nested loops to test how analysis performance scales with loop
nesting depth
- Improved the trace file analysis to extract durations for sub-phases
of the lifetime analysis (FactGenerator, LoanPropagation, ExpiredLoans)
- Enhanced the markdown report generation to include:
- Relative timing results as percentages of total Clang time
- More detailed complexity analysis for each analysis phase
Report
# Lifetime Analysis Performance Report
> Generated on: 2025-08-18 13:29:57
---
## Test Case: Pointer Cycle in Loop
**Timing Results:**
| N (Input Size) | Total Time | Analysis Time (%) | Fact Generator (%) |
Loan Propagation (%) | Expired Loans (%) |
|:---------------|-----------:|------------------:|-------------------:|---------------------:|------------------:|
| 10 | 10.75 ms | 24.61% | 0.00% | 24.38% | 0.00% |
| 25 | 64.98 ms | 86.08% | 0.00% | 86.02% | 0.00% |
| 50 | 709.37 ms | 98.53% | 0.00% | 98.51% | 0.00% |
| 75 | 3.13 s | 99.63% | 0.00% | 99.63% | 0.00% |
| 100 | 9.44 s | 99.85% | 0.00% | 99.84% | 0.00% |
| 150 | 45.31 s | 99.96% | 0.00% | 99.96% | 0.00% |
**Complexity Analysis:**
| Analysis Phase | Complexity O(n<sup>k</sup>) |
|:------------------|:--------------------------|
| Total Analysis | O(n<sup>3.87</sup> ± 0.01) |
| FactGenerator | (Negligible) |
| LoanPropagation | O(n<sup>3.87</sup> ± 0.01) |
| ExpiredLoans | (Negligible) |
---
## Test Case: CFG Merges
**Timing Results:**
| N (Input Size) | Total Time | Analysis Time (%) | Fact Generator (%) |
Loan Propagation (%) | Expired Loans (%) |
|:---------------|-----------:|------------------:|-------------------:|---------------------:|------------------:|
| 10 | 8.54 ms | 0.00% | 0.00% | 0.00% | 0.00% |
| 50 | 40.85 ms | 65.09% | 0.00% | 64.61% | 0.00% |
| 100 | 207.70 ms | 93.58% | 0.00% | 93.46% | 0.00% |
| 200 | 1.54 s | 98.82% | 0.00% | 98.78% | 0.00% |
| 400 | 12.04 s | 99.72% | 0.00% | 99.71% | 0.01% |
| 800 | 96.73 s | 99.94% | 0.00% | 99.94% | 0.00% |
**Complexity Analysis:**
| Analysis Phase | Complexity O(n<sup>k</sup>) |
|:------------------|:--------------------------|
| Total Analysis | O(n<sup>3.01</sup> ± 0.00) |
| FactGenerator | (Negligible) |
| LoanPropagation | O(n<sup>3.01</sup> ± 0.00) |
| ExpiredLoans | (Negligible) |
---
## Test Case: Deeply Nested Loops
**Timing Results:**
| N (Input Size) | Total Time | Analysis Time (%) | Fact Generator (%) |
Loan Propagation (%) | Expired Loans (%) |
|:---------------|-----------:|------------------:|-------------------:|---------------------:|------------------:|
| 10 | 8.25 ms | 0.00% | 0.00% | 0.00% | 0.00% |
| 50 | 27.25 ms | 51.87% | 0.00% | 45.71% | 5.93% |
| 100 | 113.42 ms | 82.48% | 0.00% | 72.74% | 9.62% |
| 200 | 730.05 ms | 95.24% | 0.00% | 83.95% | 11.25% |
| 400 | 5.40 s | 98.74% | 0.01% | 87.05% | 11.68% |
| 800 | 41.86 s | 99.62% | 0.00% | 87.77% | 11.84% |
**Complexity Analysis:**
| Analysis Phase | Complexity O(n<sup>k</sup>) |
|:------------------|:--------------------------|
| Total Analysis | O(n<sup>2.97</sup> ± 0.00) |
| FactGenerator | (Negligible) |
| LoanPropagation | O(n<sup>2.96</sup> ± 0.00) |
| ExpiredLoans | O(n<sup>2.97</sup> ± 0.00) |
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