Re: [PATCH 5/5] d3dcompiler: Avoid using 1-dimensional vectors as expression types.

[Zebediah Figura]

On 6/26/20 10:56 AM, Matteo Bruni wrote:
> On Tue, Jun 23, 2020 at 12:48 AM Zebediah Figura  wrote:
> > Signed-off-by: Zebediah Figura
> >
> > dlls/d3dcompiler_43/hlsl.y  | 19 +++++++++++++++----
> >  dlls/d3dcompiler_43/utils.c | 11 ++++++++---
> >  2 files changed, 23 insertions(+), 7 deletions(-)
> >
> > diff --git a/dlls/d3dcompiler_43/hlsl.y b/dlls/d3dcompiler_43/hlsl.y
> > index 21828337939..27aab195b25 100644
> > --- a/dlls/d3dcompiler_43/hlsl.y
> > +++ b/dlls/d3dcompiler_43/hlsl.y
> > @@ -416,11 +416,17 @@ static struct hlsl_ir_swizzle *new_swizzle(DWORD s, unsigned int components,
> >          struct hlsl_ir_node *val, struct source_location *loc)
> >  {
> >      struct hlsl_ir_swizzle *swizzle = d3dcompiler_alloc(sizeof(*swizzle));
> > -
> >
> > struct hlsl_type *data_type;
> >
> > if (!swizzle)
> >     return NULL;
> > - init_node(&swizzle->node, HLSL_IR_SWIZZLE,
> > -
> >        new_hlsl_type(NULL, HLSL_CLASS_VECTOR, val->data_type->base_type, components, 1), *loc);
> > -
> > - if (components == 1)
> > -
> >    data_type = hlsl_ctx.builtin_types.scalar[val->data_type->base_type];
> > - else
> > -
> >    data_type = hlsl_ctx.builtin_types.vector[val->data_type->base_type][components - 1];
> > -
> > - init_node(&swizzle->node, HLSL_IR_SWIZZLE, data_type, *loc);
> > swizzle->val = val;
> > swizzle->swizzle = s;
> > return swizzle;
> >
> > @@ -2488,6 +2494,7 @@ postfix_expr:             primary_expr
> >              for (i = 0; i < $4.args_count; ++i)
> >              {
> >                  struct hlsl_ir_node *arg = $4.args[i];
> > -
> >            struct hlsl_type *data_type;
> >            unsigned int width;
> >
> >            if (arg->data_type->type == HLSL_CLASS_OBJECT)
> >
> > @@ -2504,8 +2511,12 @@ postfix_expr:             primary_expr
> >                      continue;
> >                  }
> > -
> >            if (!(arg = add_implicit_conversion($4.instrs, arg,
> > -
> >                    hlsl_ctx.builtin_types.vector[$2->base_type][width - 1], &arg->loc)))
> > -
> >            if (width == 1)
> > -
> >                data_type = hlsl_ctx.builtin_types.scalar[$2->base_type];
> > -
> >            else
> > -
> >                data_type = hlsl_ctx.builtin_types.vector[$2->base_type][width - 1];
> > -
> > -
> >            if (!(arg = add_implicit_conversion($4.instrs, arg, data_type, &arg->loc)))
> >                continue;
> >
> >            if (!(assignment = new_assignment(var, NULL, arg,
> >
> > diff --git a/dlls/d3dcompiler_43/utils.c b/dlls/d3dcompiler_43/utils.c
> > index 30aa9de1dd4..4f0556103ab 100644
> > --- a/dlls/d3dcompiler_43/utils.c
> > +++ b/dlls/d3dcompiler_43/utils.c
> > @@ -1294,7 +1294,7 @@ static struct hlsl_type *expr_common_type(struct hlsl_type *t1, struct hlsl_type
> >          }
> >      }
> > - if (type == HLSL_CLASS_SCALAR)
> > - if (type == HLSL_CLASS_SCALAR || (type == HLSL_CLASS_VECTOR && dimx == 1))
> >     return hlsl_ctx.builtin_types.scalar[base];
> > if (type == HLSL_CLASS_VECTOR)
> >     return hlsl_ctx.builtin_types.vector[base][dimx - 1];
> >
> > @@ -1496,9 +1496,14 @@ struct hlsl_ir_node *add_assignment(struct list *instrs, struct hlsl_ir_node *lh
> >                  d3dcompiler_free(assign);
> >                  return NULL;
> >              }
> > -
> >        assert(swizzle_type->type == HLSL_CLASS_VECTOR);
> > -
> >        assert(swizzle_type->type == HLSL_CLASS_VECTOR || swizzle_type->type == HLSL_CLASS_SCALAR);
> >        if (swizzle_type->dimx != width)
> > -
> >            swizzle->node.data_type = hlsl_ctx.builtin_types.vector[swizzle_type->base_type][width - 1];
> > -
> >        {
> > -
> >            if (width == 1)
> > -
> >                swizzle->node.data_type = hlsl_ctx.builtin_types.scalar[swizzle_type->base_type];
> > -
> >            else
> > -
> >                swizzle->node.data_type = hlsl_ctx.builtin_types.vector[swizzle_type->base_type][width - 1];
> > -
> >        }
> >        rhs = &swizzle->node;
> >    }
> >    else
>
> What do we gain with this?

Not having to deal with vec1 at codegen time, basically, or along
similar lines not having superfluous instructions to cast it to scalar.
Granted, it still exists, but you'd have to use it intentionally...