On Tue, May 26, 2015 at 1:13 PM, Bin.Cheng <amker.ch...@gmail.com> wrote: > Hi, > The first part patch improving how we handle overflow in scev is > posted at https://gcc.gnu.org/ml/gcc-patches/2015-05/msg01795.html . > Here comes the second part patch. > > This patch does below improvements: > 1) Computes and records control iv for each loop's exit edge. This > provides a way to compute overflow information in loop niter and use > it in different customers. It think it's useful, especially with > option -funsafe-loop-optimizers. > 2) Improve chrec_convert by adding new interface > loop_exits_before_overflow. It checks if a converted IV overflows > wrto its type and loop using overflow information of loop's control > iv. This basically propagates no-overflow information from control iv > to ivs converted from control iv. Moreover, we can further improve > the logic by using possible VRP information in the future. > > With this patch, cases like scev-9.c and scev-10.c in patch can be > handled now. Cases reported in PR48052 can be vectorized too. > Opinions?
-ENOPATCH > Thanks, > bin > > > 2015-05-26 Bin Cheng <bin.ch...@arm.com> > > * cfgloop.h (struct control_iv): New. > (struct loop): New field control_ivs. > * tree-ssa-loop-niter.c : Include "stor-layout.h". > (number_of_iterations_lt): Set no_overflow information. > (number_of_iterations_exit): Init control iv in niter struct. > (record_control_iv): New. > (estimate_numbers_of_iterations_loop): Call record_control_iv. > (loop_exits_before_overflow): New. Interface factored out of > scev_probably_wraps_p. > (scev_probably_wraps_p): Factor loop niter related code into > loop_exits_before_overflow. > (free_numbers_of_iterations_estimates_loop): Free control ivs. > * tree-ssa-loop-niter.h (free_loop_control_ivs): New. > > gcc/testsuite/ChangeLog > 2015-05-26 Bin Cheng <bin.ch...@arm.com> > > PR tree-optimization/48052 > * gcc.dg/tree-ssa/scev-8.c: New. > * gcc.dg/tree-ssa/scev-9.c: New. > * gcc.dg/tree-ssa/scev-10.c: New. > * gcc.dg/vect/pr48052.c: New.
