On Tue, Nov 14, 2023 at 1:56 AM liuhongt <hongtao....@intel.com> wrote:
>
> if (TREE_CODE (init_expr) == INTEGER_CST)
> init_expr = fold_convert (TREE_TYPE (vectype), init_expr);
> else
> gcc_assert (tree_nop_conversion_p (TREE_TYPE (vectype),
> TREE_TYPE (init_expr)));
>
> and init_expr is a 24 bit integer type while vectype has 32bit components.
>
> The "fix" is to bail out instead of asserting.
>
> Bootstrapped and regtested on x86_64-pc-linux-gnu{-m32,}.
> Ok for trunk?(and backport to GCC-13)
OK for both.
Thanks,
Richard.
> gcc/ChangeLog:
>
> PR tree-optimization/112496
> * tree-vect-loop.cc (vectorizable_nonlinear_induction): Return
> false when !tree_nop_conversion_p (TREE_TYPE (vectype),
> TREE_TYPE (init_expr).
>
> gcc/testsuite/ChangeLog:
>
> * gcc.target/i386/pr112496.c: New test.
> ---
> gcc/testsuite/gcc.target/i386/pr112496.c | 7 +++++++
> gcc/tree-vect-loop.cc | 13 ++++++++++---
> 2 files changed, 17 insertions(+), 3 deletions(-)
> create mode 100644 gcc/testsuite/gcc.target/i386/pr112496.c
>
> diff --git a/gcc/testsuite/gcc.target/i386/pr112496.c
> b/gcc/testsuite/gcc.target/i386/pr112496.c
> new file mode 100644
> index 00000000000..c478fda9cce
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/i386/pr112496.c
> @@ -0,0 +1,7 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2" } */
> +
> +struct T { int x : 24; } v;
> +void f1(int x) {
> + while (v.x - ((v.x <<= 1) - v.x)) ;
> +}
> diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
> index 1304b7ece79..75d69bbc30e 100644
> --- a/gcc/tree-vect-loop.cc
> +++ b/gcc/tree-vect-loop.cc
> @@ -9429,9 +9429,16 @@ vectorizable_nonlinear_induction (loop_vec_info
> loop_vinfo,
>
> if (TREE_CODE (init_expr) == INTEGER_CST)
> init_expr = fold_convert (TREE_TYPE (vectype), init_expr);
> - else
> - gcc_assert (tree_nop_conversion_p (TREE_TYPE (vectype),
> - TREE_TYPE (init_expr)));
> + else if (!tree_nop_conversion_p (TREE_TYPE (vectype), TREE_TYPE
> (init_expr)))
> + {
> + /* INIT_EXPR could be a bit_field, bail out for such case. */
> + if (dump_enabled_p ())
> + dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
> + "nonlinear induction vectorization failed:"
> + " component type of vectype is not a nop conversion"
> + " from type of init_expr.\n");
> + return false;
> + }
>
> switch (induction_type)
> {
> --
> 2.31.1
>
