Fold_stmt releases SSA names on simplification failure.
The fold_stmt function now releases SSA names when match-and-simplify fails, preventing memory leaks.
The fold_stmt function in gimple-fold.cc now discards statements in the sequence after a failed gimple_simplify attempt. This prevents memory leaks by releasing SSA names that were pushed but not ultimately used due to simplification failure. This fix addresses PR middle-end/125146.
In Details
The fold_stmt function attempts to simplify GIMPLE statements using a match-and-simplify approach. When simplification fails, any statements that were temporarily pushed during the process need to be discarded to avoid memory leaks. This commit ensures that these statements are properly released, specifically addressing the issue of unreleased SSA names. This change impacts the gimple-fold.cc file in the compiler's middle-end.
For Context
Compilers often try to simplify code to make it more efficient. This involves a process of pattern matching and replacement. If this simplification process fails, it's important to clean up any temporary data that was created during the attempt. This commit addresses a memory management issue in GCC where temporary data related to Single Static Assignment (SSA) names was not being properly released when simplification failed. This prevents memory leaks and ensures the compiler remains stable.