[PATCH] D49536: [Analyzer] Quick Fix for exponential execution time when simpilifying complex additive expressions

[Balogh, Ádám via Phabricator via cfe-commits]

baloghadamsoftware created this revision.
baloghadamsoftware added a reviewer: NoQ.
Herald added subscribers: mikhail.ramalho, a.sidorin, dkrupp, rnkovacs, szepet, xazax.hun, whisperity.
Herald added a reviewer: george.karpenkov.

Patch [[https://reviews.llvm.org/rC329780 | [Analyzer] SValBuilder Comparison Rearrangement (with Restrictions and Analyzer Option) ]] not only rearranges comparisons but also binary expressions. This latter behavior is not protected by the analyzer option. Hower, since no complexity threshold is enforced to the symbols this may result in exponential execution time if the expressions are too complex: Huge static analysis performance regression for very simple testcase <https://bugs.llvm.org/show_bug.cgi?id=38208> For a quick fix we extended the analyzer option to also cover the additive cases.

This is only a temporary fix, the final solution should be enforcing the complexity threshold to the symbols.


https://reviews.llvm.org/D49536

Files:
  include/clang/StaticAnalyzer/Core/AnalyzerOptions.h
  lib/StaticAnalyzer/Core/AnalyzerOptions.cpp
  lib/StaticAnalyzer/Core/SimpleSValBuilder.cpp
  test/Analysis/PR38208.c
  test/Analysis/constraint_manager_negate_difference.c
  test/Analysis/iterator-range.cpp
  test/Analysis/plist-macros.cpp
  test/Analysis/svalbuilder-rearrange-comparisons.c

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