Ping. Thanks, bin
On Tue, Jul 28, 2015 at 5:36 PM, Bin Cheng <bin.ch...@arm.com> wrote: > Hi, > Loop niter computes inaccurate bound information for different loops. This > patch is to improve it by using loop initial condition in > determine_value_range. Generally, loop niter is computed by subtracting > start var from end var in loop exit condition. Moreover, loop bound is > computed using value range information of both start and end variables. > Basic idea of this patch is to check if loop initial condition implies more > range information for both start/end variables. If yes, we refine range > information and use that to compute loop bound. > With this improvement, more accurate loop bound information is computed for > test cases added by this patch. > > Is it OK? > > Thanks, > bin > > 2015-07-28 Bin Cheng <bin.ch...@arm.com> > > * tree-ssa-loop-niter.c (refine_value_range_using_guard): New. > (determine_value_range): Call refine_value_range_using_guard for > each loop initial condition to improve value range. > > gcc/testsuite/ChangeLog > 2015-07-28 Bin Cheng <bin.ch...@arm.com> > > * gcc.dg/tree-ssa/loop-bound-1.c: New test. > * gcc.dg/tree-ssa/loop-bound-3.c: New test. > * gcc.dg/tree-ssa/loop-bound-5.c: New test.
