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

[Matteo Bruni]

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?
-------------- next part --------------
diff --git a/libs/vkd3d-shader/hlsl_codegen.c b/libs/vkd3d-shader/hlsl_codegen.c
index e8456694..5e85fa2f 100644
--- a/libs/vkd3d-shader/hlsl_codegen.c
+++ b/libs/vkd3d-shader/hlsl_codegen.c
@@ -242,6 +242,18 @@ static void replace_and_remove_node(struct hlsl_ir_node *old, struct hlsl_ir_nod
     hlsl_free_instr(old);
 }
 
+/* Replace an instruction with a swizzle instruction. */
+static void replace_swizzle(struct hlsl_ir_node *old, struct hlsl_ir_swizzle *swizzle)
+{
+    struct hlsl_ir_node *val_instr = swizzle->val.node;
+
+    /* If old is the argument of swizzle, simply doing replace_node() would
+     * make swizzle have itself as argument. */
+    hlsl_src_remove(&swizzle->val);
+    replace_node(old, &swizzle->node);
+    hlsl_src_from_node(&swizzle->val, val_instr);
+}
+
 /* Lower casts from vec1 to vecN to swizzles. */
 static bool lower_broadcasts(struct hlsl_ctx *ctx, struct hlsl_ir_node *instr, void *context)
 {
@@ -267,9 +279,7 @@ static bool lower_broadcasts(struct hlsl_ctx *ctx, struct hlsl_ir_node *instr, v
         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);
+        replace_swizzle(&cast->node, swizzle);
         return true;
     }