[PATCH vkd3d 4/5] vkd3d-shader/hlsl: Parse the max() intrinsic.

[Matteo Bruni]

On Thu, Sep 2, 2021 at 12:23 AM Zebediah Figura <zfigura at codeweavers.com> wrote:
>
> Signed-off-by: Zebediah Figura <zfigura at codeweavers.com>
> ---
>  Makefile.am                 |  2 ++
>  libs/vkd3d-shader/hlsl.y    | 67 +++++++++++++++++++++++++++++++++++++
>  tests/max.shader_test       | 23 +++++++++++++
>  tests/shader_runner_d3d12.c |  2 ++
>  4 files changed, 94 insertions(+)
>  create mode 100644 tests/max.shader_test

> diff --git a/libs/vkd3d-shader/hlsl.y b/libs/vkd3d-shader/hlsl.y
> index 2512bcc0..d374f64b 100644
> --- a/libs/vkd3d-shader/hlsl.y
> +++ b/libs/vkd3d-shader/hlsl.y
> @@ -1555,10 +1555,38 @@ static const struct hlsl_ir_function_decl *find_function_call(struct hlsl_ctx *c
>      return args.decl;
>  }
>
> +static bool intrinsic_max(struct hlsl_ctx *ctx,
> +        const struct parse_initializer *params, struct vkd3d_shader_location loc)
> +{
> +    struct hlsl_ir_node *args[3] = {params->args[0], params->args[1]};
> +
> +    return !!add_expr(ctx, params->instrs, HLSL_OP2_MAX, args, &loc);
> +}
> +
> +static const struct intrinsic_function
> +{
> +    const char *name;
> +    int param_count;
> +    bool check_numeric;
> +    bool (*handler)(struct hlsl_ctx *ctx, const struct parse_initializer *params, struct vkd3d_shader_location loc);
> +}
> +intrinsic_functions[] =
> +{
> +    {"max",                                 2, true,  intrinsic_max},
> +};
> +
> +static int intrinsic_function_name_compare(const void *a, const void *b)
> +{
> +    const struct intrinsic_function *func = b;
> +
> +    return strcmp(a, func->name);
> +}
> +
>  static struct list *add_call(struct hlsl_ctx *ctx, const char *name,
>          struct parse_initializer *params, struct vkd3d_shader_location loc)
>  {
>      const struct hlsl_ir_function_decl *decl;
> +    struct intrinsic_function *intrinsic;
>
>      if ((decl = find_function_call(ctx, name, params)))
>      {
> @@ -1566,6 +1594,45 @@ static struct list *add_call(struct hlsl_ctx *ctx, const char *name,
>          free_parse_initializer(params);
>          return NULL;
>      }
> +    else if ((intrinsic = bsearch(name, intrinsic_functions, ARRAY_SIZE(intrinsic_functions),
> +            sizeof(*intrinsic_functions), intrinsic_function_name_compare)))
> +    {
> +        if (intrinsic->param_count >= 0 && params->args_count != intrinsic->param_count)
> +        {
> +            hlsl_error(ctx, loc, VKD3D_SHADER_ERROR_HLSL_WRONG_PARAMETER_COUNT,
> +                    "Wrong number of arguments to function '%s': expected %u, but got %u.\n",
> +                    name, intrinsic->param_count, params->args_count);
> +            free_parse_initializer(params);
> +            return NULL;
> +        }

I guess the idea is to use param_count == 0 to mark intrinsic
functions with a variable number of parameters? I think it would be
better to use a different number (e.g. -1 if you keep int for
param_count, or ~0u otherwise) given that we probably want to check
that calls to e.g. AllMemoryBarrier() don't have arguments.