================ @@ -0,0 +1,200 @@ +// RUN: %clang_analyze_cc1 -analyzer-checker=core,debug.ExprInspection -verify=expected,default %s +// RUN: %clang_analyze_cc1 -analyzer-checker=core,debug.ExprInspection -analyzer-config inline-functions-with-ambiguous-loops=true -verify=expected,enabled %s + +// This file tests some heuristics in the engine that put functions on a +// "do not inline" list if their analyisis reaches the `analyzer-max-loop` +// limit (by default 4 iterations) in a loop. This was almost surely intended +// as memoization optimization for the "retry without inlining" fallback (if we +// had to retry once, next time don't even try inlining), but aggressively +// oversteps the "natural" scope: reaching 4 iterations on _one particular_ +// execution path does not imply that each path would need "retry without +// inlining" especially if a different call receives different arguments. +// +// This heuristic significantly affects the scope/depth of the analysis (and +// therefore the execution time) because without this limitation on the +// inlining significantly more entry points would be able to exhaust their +// `max-nodes` quota. (Trivial thin wrappers around big complex functions are +// common in many projects.) +// +// Unfortunately, this arbitrary heuristic strongly relies on the current loop +// handling model and its many limitations, so improvements in loop handling +// can cause surprising slowdowns by reducing the "do not inline" blacklist. +// In the tests "FIXME-BUT-NEEDED" comments mark "problematic" (aka buggy) +// analyzer behavior which cannot be fixed without also improving the +// heuristics for (not) inlining large functions. + + int getNum(void); // Get an unknown symbolic number. ---------------- steakhal wrote:
I'm deliberately not touching this. I want to keep this as close to the original one as possible. https://github.com/llvm/llvm-project/pull/139597 _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
