Reuse computed values efficiently

Move variable declarations and computations outside of loops when their values don't change between iterations. This reduces memory allocations and avoids redundant computations, improving performance.

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Move variable declarations and computations outside of loops when their values don’t change between iterations. This reduces memory allocations and avoids redundant computations, improving performance.

Example - Before:

for (const auto& resource_entry : manager->held_locks_) {
  for (const auto& held_lock : resource_entry.second) {
    Local<Object> lock_info = CreateLockInfoObject(...);
    // Use lock_info
  }
}

Example - After:

Local<Object> lock_info;
for (const auto& resource_entry : manager->held_locks_) {
  for (const auto& held_lock : resource_entry.second) {
    lock_info = CreateLockInfoObject(...);
    // Use lock_info
  }
}

Similarly, cache computed values that are used repeatedly:

// Before: Computing in every call
std::string normalised_cache_dir = NormalisePath(cache_dir);

// After: Store as member variable
class CompileCacheHandler {
  std::string normalised_cache_dir_;
  // Compute once in constructor
};

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