r246021 - in /trunk/gcc: ChangeLog testsuite/Ch...

[jakub@gcc.gnu.org]

Author: jakub
Date: Fri Mar 10 07:53:57 2017
New Revision: 246021

URL: https://gcc.gnu.org/viewcvs?rev=246021&root=gcc&view=rev
Log:
	PR tree-optimization/77975
	* tree-ssa-loop-niter.c (get_base_for): Allow phi argument from latch
	edge to be constant.
	(get_val_for): For constant x return it.  Formatting fix.
	(loop_niter_by_eval): Avoid pointless looping if the next iteration
	would use the same bases as the current one.

	* gcc.dg/pr77975.c: New test.

Added:
    trunk/gcc/testsuite/gcc.dg/pr77975.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-loop-niter.c