Re: [PATCH vkd3d 5/6] vkd3d-shader/hlsl: Fold constant not-equal expressions.

[Francisco Casas]

Oh, never mind, I forgot that hlsl_alloc() does a calloc() and initializes
the memory to 0.

I still think it may be safer to compare the .b-s separately.
If say, we reuse a hlsl_ir_constant value somewhere and change its type from
HLSL_TYPE_INT to HLSL_TYPE_BOOL.

Signed-off-by: Francisco Casas

March 24, 2022 5:07 PM, "Francisco Casas"  wrote:
> Hello,
>
> March 23, 2022 11:28 AM, "Giovanni Mascellani"  wrote:
> > Signed-off-by: Giovanni Mascellani
> >
> > libs/vkd3d-shader/hlsl_constant_ops.c | 41 +++++++++++++++++++++++++++
> > 1 file changed, 41 insertions(+)
> >
> > diff --git a/libs/vkd3d-shader/hlsl_constant_ops.c b/libs/vkd3d-shader/hlsl_constant_ops.c
> > index 6c852ba1..2f090863 100644
> > --- a/libs/vkd3d-shader/hlsl_constant_ops.c
> > +++ b/libs/vkd3d-shader/hlsl_constant_ops.c
> > @@ -224,6 +224,43 @@ static bool fold_mul(struct hlsl_ctx *ctx, struct hlsl_ir_constant *dst,
> > return true;
> > }
> >
> > +static bool fold_nequal(struct hlsl_ctx *ctx, struct hlsl_ir_constant *dst,
> > - struct hlsl_ir_constant *src1, struct hlsl_ir_constant *src2)
> >
> > +{
> > - enum hlsl_base_type type = dst->node.data_type->base_type;
> > -
> > - assert(type == HLSL_TYPE_BOOL);
> > - assert(src1->node.data_type->base_type == src2->node.data_type->base_type);
> > -
> > - for (int k = 0; k < 4; ++k)
> > - {
> > - switch (src1->node.data_type->base_type)
> > - {
> > - case HLSL_TYPE_FLOAT:
> > - case HLSL_TYPE_HALF:
> > - dst->value[k].b = src1->value[k].f != src2->value[k].f;
> > - break;
> > -
> > - case HLSL_TYPE_DOUBLE:
> > - dst->value[k].b = src1->value[k].d != src2->value[k].d;
> > - break;
> > -
> > - case HLSL_TYPE_INT:
> > - case HLSL_TYPE_UINT:
> > - case HLSL_TYPE_BOOL:
> > - dst->value[k].b = src1->value[k].u != src2->value[k].u;
>
> I am not so sure we can compare bools using .u, since sizeof(bool) is 1.
> The next 3 bytes may not be initialized.
> (more probably now that we have hlsl_new_constant()).
> > - break;
> > -
> > - default:
> > - FIXME("Fold not-equal for type %s.\n", debug_hlsl_type(ctx, dst->node.data_type));
> > - return false;
> > - }
> > -
> > - dst->value[k].b *= ~0u;
> > - }
> > - return true;
> >
> > +}
> > -
> >
> > bool hlsl_fold_constants(struct hlsl_ctx *ctx, struct hlsl_ir_node *instr, void *context)
> > {
> > struct hlsl_ir_constant *arg1, *arg2 = NULL, *res;
> > @@ -266,6 +303,10 @@ bool hlsl_fold_constants(struct hlsl_ctx *ctx, struct hlsl_ir_node *instr,
> > void
> > success = fold_mul(ctx, res, arg1, arg2);
> > break;
> > - case HLSL_OP2_NEQUAL:
> > - success = fold_nequal(ctx, res, arg1, arg2);
> > - break;
> > -
> >
> > default:
> > FIXME("Fold "%s" expression.\n", debug_hlsl_expr_op(expr->op));
> > success = false;
> > --
> > 2.35.1
>
> Best regards,
> Francisco.