[PATCH vkd3d 3/6] vkd3d-shader/hlsl: Lower scalar-to-vector casts to swizzles.

[Zebediah Figura]

On 11/26/21 13:37, Matteo Bruni wrote:
> On Tue, Nov 23, 2021 at 2:46 AM Zebediah Figura <zfigura at codeweavers.com> wrote:
>>
>> Signed-off-by: Zebediah Figura <zfigura at codeweavers.com>
>> ---
>>   Makefile.am                      |  1 -
>>   libs/vkd3d-shader/hlsl_codegen.c | 33 ++++++++++++++++++++++++++++++++
>>   2 files changed, 33 insertions(+), 1 deletion(-)
>>
>> diff --git a/Makefile.am b/Makefile.am
>> index be3d8ec15..4010533af 100644
>> --- a/Makefile.am
>> +++ b/Makefile.am
>> @@ -290,7 +290,6 @@ XFAIL_TESTS = \
>>          tests/conditional.shader_test \
>>          tests/hlsl-array-dimension.shader_test \
>>          tests/hlsl-bool-cast.shader_test \
>> -       tests/hlsl-comma.shader_test \
>>          tests/hlsl-cross.shader_test \
>>          tests/hlsl-duplicate-modifiers.shader_test \
>>          tests/hlsl-for.shader_test \
>> diff --git a/libs/vkd3d-shader/hlsl_codegen.c b/libs/vkd3d-shader/hlsl_codegen.c
>> index 2c620c7d7..b69df47a0 100644
>> --- a/libs/vkd3d-shader/hlsl_codegen.c
>> +++ b/libs/vkd3d-shader/hlsl_codegen.c
>> @@ -242,6 +242,38 @@ static void replace_and_remove_node(struct hlsl_ir_node *old, struct hlsl_ir_nod
>>       hlsl_free_instr(old);
>>   }
>>
>> +/* Lower casts from vec1 to vecN to swizzles. */
>> +static bool lower_broadcasts(struct hlsl_ctx *ctx, struct hlsl_ir_node *instr, void *context)
>> +{
>> +    const struct hlsl_type *src_type, *dst_type;
>> +    struct hlsl_ir_expr *cast;
>> +
>> +    if (instr->type != HLSL_IR_EXPR)
>> +        return false;
>> +    cast = hlsl_ir_expr(instr);
>> +    src_type = cast->operands[0].node->data_type;
>> +    dst_type = cast->node.data_type;
>> +
>> +    if (cast->op == HLSL_OP1_CAST
>> +            && src_type->type <= HLSL_CLASS_VECTOR && dst_type->type <= HLSL_CLASS_VECTOR
>> +            && src_type->dimx == 1)
>> +    {
>> +        struct hlsl_ir_swizzle *swizzle;
>> +
>> +        if (!(swizzle = hlsl_new_swizzle(ctx, HLSL_SWIZZLE(X, X, X, X), dst_type->dimx, &cast->node, &cast->node.loc)))
>> +            return false;
>> +        list_add_after(&cast->node.entry, &swizzle->node.entry);
>> +
>> +        cast->node.data_type = hlsl_get_scalar_type(ctx, dst_type->base_type);
>> +        replace_node(&cast->node, &swizzle->node);
>> +        hlsl_src_remove(&swizzle->val);
>> +        hlsl_src_from_node(&swizzle->val, &cast->node);
> 
> This seems a bit opaque to me. What do you think about the attached
> change on top of this patch?
> 

Unlike Giovanni I do think that helps :-)

Although at this point I'm more and more inclined to agree with 
Giovanni's original suggestion, i.e. just create a new node anyway, and 
get rid of patch 2/6.