On Thu, May 30, 2019 at 12:02 AM Marc Glisse <marc.gli...@inria.fr> wrote:
>
> On Mon, 20 May 2019, Richard Biener wrote:
>
> > On Sun, May 19, 2019 at 6:22 PM Marc Glisse <marc.gli...@inria.fr> wrote:
> >>
> >> Hello,
> >>
> >> I noticed this one with BIT_NOT_EXPR a while ago. C++ testcase because I
> >> haven't looked at gimplefe yet...
> >
> > OK. I wonder if there's any issue with -ftrapv and negate/abs of
> > INT_MIN containing vectors (we don't implement -ftrapv optabs for
> > vectors of course...).
> > We at least avoid folding those cases I think and sanitizers then may
> > see those unconditionally?
>
> The new version of the patch checks that both sides can indeed be folded
> to constants before doing the transformation. We should have the same
> for functions like sqrt, but fold_const_call does not seem to handle
> vectors :-(
Looks good to me. Btw, no reason to not extend fold_const_call to handle
the vector case ;)
Richard.
> @@ -2911,20 +2913,35 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> @2)
> (if (!VOID_TYPE_P (TREE_TYPE (@1)) || VOID_TYPE_P (type))
> @1)))
> (simplify
> (vec_cond VECTOR_CST@0 @1 @2)
> (if (integer_all_onesp (@0))
> @1
> (if (integer_zerop (@0))
> @2)))
>
> +/* Sink unary operations to constant branches, but only if we do fold it to
> + constants. */
> +(for op (negate bit_not abs absu)
> + (simplify
> + (op (vec_cond @0 VECTOR_CST@1 VECTOR_CST@2))
> + (with
> + {
> + tree cst1, cst2;
> + cst1 = const_unop (op, type, @1);
> + if (cst1)
> + cst2 = const_unop (op, type, @2);
> + }
> + (if (cst1 && cst2)
> + (vec_cond @0 { cst1; } { cst2; })))))
> +
> /* Simplification moved from fold_cond_expr_with_comparison. It may also
> be extended. */
> /* This pattern implements two kinds simplification:
>
> Case 1)
> (cond (cmp (convert1? x) c1) (convert2? x) c2) -> (minmax (x c)) if:
> 1) Conversions are type widening from smaller type.
> 2) Const c1 equals to c2 after canonicalizing comparison.
> 3) Comparison has tree code LT, LE, GT or GE.
> This specific pattern is needed when (cmp (convert x) c) may not
>
>
> >> 2019-05-20 Marc Glisse <marc.gli...@inria.fr>
> >>
> >> gcc/
> >> * match.pd (~(vec?cst1:cst2)); New transformation.
> >>
> >> gcc/testsuite/
> >> * g++.dg/tree-ssa/cprop-vcond.C
>
> --
> Marc Glisse
