On Sun, Jul 7, 2013 at 10:54 AM, Marc Glisse <marc.gli...@inria.fr> wrote:
> Hello,
>
> it turns out there wasn't much missing here. I got side-tracked because
> fold_unary_loc doesn't call fold_indirect_ref_1, and fold_indirect_ref_1 has
> a too strict comparison type == TREE_TYPE (optype) (should compare
> TYPE_MAIN_VARIANT instead?),
or same_type_p.
> but none of that was necessary so I'll leave it
> for another time. The new testcase is not that useful, but I didn't remember
> there was already one with dg-bogus.
>
>
> Bootstrap+testsuite on x86_64-unknown-linux-gnu.
>
> 2013-07-07 Marc Glisse <marc.gli...@inria.fr>
>
> PR c++/53094
> gcc/cp/
> * semantics.c (cxx_eval_bit_field_ref): Handle VECTOR_CST.
OK.
>
> gcc/testsuite/
> * g++.dg/cpp0x/constexpr-53094-1.C: Adjust.
> * g++.dg/ext/vector24.C: New testcase.
>
> --
> Marc Glisse
> Index: testsuite/g++.dg/cpp0x/constexpr-53094-1.C
> ===================================================================
> --- testsuite/g++.dg/cpp0x/constexpr-53094-1.C (revision 200742)
> +++ testsuite/g++.dg/cpp0x/constexpr-53094-1.C (working copy)
> @@ -1,6 +1,6 @@
> // { dg-do compile }
> // { dg-options "-std=gnu++11" }
>
> typedef float __attribute__ ((vector_size (4 * sizeof (float)))) V4;
> constexpr V4 v = { 1, 1, 1, 0 };
> -constexpr V4 r = v[0] + v; // { dg-bogus "not a constant expression" "" {
> xfail *-*-* } }
> +constexpr V4 r = v[0] + v;
> Index: testsuite/g++.dg/ext/vector24.C
> ===================================================================
> --- testsuite/g++.dg/ext/vector24.C (revision 0)
> +++ testsuite/g++.dg/ext/vector24.C (revision 0)
> @@ -0,0 +1,8 @@
> +// { dg-do compile { target c++11 } }
> +
> +typedef long vec __attribute__((vector_size(2*sizeof(long))));
> +constexpr vec v = { 33, 42 };
> +constexpr auto l0 = v[0];
> +constexpr auto l1 = v[1];
> +static_assert(l0==33,"Fail");
> +static_assert(l1==42,"Fail");
>
> Property changes on: testsuite/g++.dg/ext/vector24.C
> ___________________________________________________________________
> Added: svn:eol-style
> + native
> Added: svn:keywords
> + Author Date Id Revision URL
>
> Index: cp/semantics.c
> ===================================================================
> --- cp/semantics.c (revision 200742)
> +++ cp/semantics.c (working copy)
> @@ -7179,29 +7179,35 @@ cxx_eval_bit_field_ref (const constexpr_
> tree whole = cxx_eval_constant_expression (call, orig_whole,
> allow_non_constant, addr,
> non_constant_p, overflow_p);
> tree start, field, value;
> unsigned HOST_WIDE_INT i;
>
> if (whole == orig_whole)
> return t;
> /* Don't VERIFY_CONSTANT here; we only want to check that we got a
> CONSTRUCTOR. */
> - if (!*non_constant_p && TREE_CODE (whole) != CONSTRUCTOR)
> + if (!*non_constant_p
> + && TREE_CODE (whole) != VECTOR_CST
> + && TREE_CODE (whole) != CONSTRUCTOR)
> {
> if (!allow_non_constant)
> error ("%qE is not a constant expression", orig_whole);
> *non_constant_p = true;
> }
> if (*non_constant_p)
> return t;
>
> + if (TREE_CODE (whole) == VECTOR_CST)
> + return fold_ternary (BIT_FIELD_REF, TREE_TYPE (t), whole,
> + TREE_OPERAND (t, 1), TREE_OPERAND (t, 2));
> +
> start = TREE_OPERAND (t, 2);
> istart = tree_low_cst (start, 0);
> isize = tree_low_cst (TREE_OPERAND (t, 1), 0);
> utype = TREE_TYPE (t);
> if (!TYPE_UNSIGNED (utype))
> utype = build_nonstandard_integer_type (TYPE_PRECISION (utype), 1);
> retval = build_int_cst (utype, 0);
> FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (whole), i, field, value)
> {
> tree bitpos = bit_position (field);
>
