On Sun, Aug 26, 2012 at 4:28 PM, Tom de Vries <tom_devr...@mentor.com> wrote: > Richard, > > this patch fixes PR53986. > > The patch calculates the range of an LSHIFT_EXPR in case both operands are > constants ranges, and the operation is guaranteed not to overflow. > > F.i., it evaluates [1, 2] << [1, 8] to [2, 512]. > > Bootstrapped and reg-tested (ada inclusive) on x86_64. > > Ok for trunk?
Ok. Thanks, Richard. > Thanks, > - Tom > > 2012-08-25 Tom de Vries <t...@codesourcery.com> > > PR tree-optimization/53986 > * tree-vrp.c (extract_range_from_multiplicative_op_1): Allow > LSHIFT_EXPR. > (extract_range_from_binary_expr_1): Handle LSHIFT with constant range > as > shift amount. > > * gcc.dg/tree-ssa/vrp80.c: New test. > * gcc.dg/tree-ssa/vrp80-2.c: Same.
