[Piglit] [PATCH 04/10] arb_enhanced_layouts: add aliasing tests with mixed type widths

Andres Gomez agomez at igalia.com
Wed Mar 20 10:44:30 UTC 2019


On Wed, 2019-03-20 at 20:56 +1100, Timothy Arceri wrote:
> 
> On 20/3/19 7:58 pm, Juan A. Suarez Romero wrote:
> > For the 4 first patches in the series:
> > 
> > Reviewed-by: Juan A. Suarez <jasuarez at igalia.com>
> > 
> > 
> > On Fri, 2019-02-01 at 19:55 +0200, Andres Gomez wrote:
> > > Added tests which check component aliasing between types that have
> > > different bit widths.
> > > 
> > >  From Section 4.4.1 (Input Layout Qualifiers) of the GLSL 4.60 spec:
> > > 
> > >      "Further, when location aliasing, the aliases sharing the location
> > >       must have the same underlying numerical type and bit
> > >       width (floating-point or integer, 32-bit versus 64-bit, etc.)
> > >       and the same auxiliary storage and interpolation
> > >       qualification. The one exception where component aliasing is
> > >       permitted is for two input variables (not block members) to a
> > >       vertex shader, which are allowed to have component aliasing. This
> > >       vertex-variable component aliasing is intended only to support
> > >       vertex shaders where each execution path accesses at most one
> > >       input per each aliased component. Implementations are permitted,
> > >       but not required, to generate link-time errors if they detect
> > >       that every path through the vertex shader executable accesses
> > >       multiple inputs aliased to any single component."
> > > 
> > > Cc: Timothy Arceri <tarceri at itsqueeze.com>
> > > Cc: Iago Toral Quiroga <itoral at igalia.com>
> > > Cc: Ilia Mirkin <imirkin at alum.mit.edu>
> > > Signed-off-by: Andres Gomez <agomez at igalia.com>
> > > ---
> > >   .../type-mismatch-signed-double.vert          | 59 +++++++++++++++++++
> > >   .../width-mismatch-float-double.vert          | 59 +++++++++++++++++++
> > >   ...s-width-mismatch-double-float.shader_test} | 25 ++++----
> > >   3 files changed, 131 insertions(+), 12 deletions(-)
> > >   create mode 100644 tests/spec/arb_enhanced_layouts/compiler/component-layout/type-mismatch-signed-double.vert
> > >   create mode 100644 tests/spec/arb_enhanced_layouts/compiler/component-layout/width-mismatch-float-double.vert
> > >   rename tests/spec/arb_enhanced_layouts/linker/component-layout/{vs-to-fs-type-mismatch-double-float.shader_test => vs-to-fs-width-mismatch-double-float.shader_test} (56%)
> > > 
> > > diff --git a/tests/spec/arb_enhanced_layouts/compiler/component-layout/type-mismatch-signed-double.vert b/tests/spec/arb_enhanced_layouts/compiler/component-layout/type-mismatch-signed-double.vert
> > > new file mode 100644
> > > index 000000000..01bfb0df1
> > > --- /dev/null
> > > +++ b/tests/spec/arb_enhanced_layouts/compiler/component-layout/type-mismatch-signed-double.vert
> > > @@ -0,0 +1,59 @@
> > > +// [config]
> > > +// expect_result: pass
> > > +// glsl_version: 1.50
> > > +// check_link: true
> > > +// require_extensions: GL_ARB_enhanced_layouts GL_ARB_explicit_attrib_location GL_ARB_gpu_shader_fp64 GL_ARB_vertex_attrib_64bit
> > > +// [end config]
> > > +//
> > > +// From Section 4.4.1 (Input Layout Qualifiers) of the GLSL 4.50 spec:
> > > +//
> > > +//   "Further, when location aliasing, the aliases sharing the location must
> > > +//   have the same underlying numerical type (floating-point or integer) and
> > > +//   the same auxiliary storage and interpolation qualification"
> > > +//
> > > +//   ...
> > > +//
> > > +//   "The one exception where component aliasing is permitted is for two input
> > > +//   variables (not block members) to a vertex shader, which are allowed to
> > > +//   have component aliasing. This vertex-variable component aliasing is
> > > +//   intended only to support vertex shaders where each execution path
> > > +//   accesses at most one input per each aliased component.  Implementations
> > > +//   are permitted, but not required, to generate link-time errors if they
> > > +//   detect that every path through the vertex shader executable accesses
> > > +//   multiple inputs aliased to any single component."
> > > +//
> > > +//   Issue 16 from the ARB_enhanced_layouts spec:
> > > +//
> > > +//   "We do allow this for vertex shader inputs, because we've supported
> > > +//   "aliasing" behavior since OpenGL 2.0. This allows for an "uber-shader"
> > > +//    with variables like:
> > > +//
> > > +//          layout(location=3) in float var1;
> > > +//          layout(location=3) in int var2;
> > > +//
> > > +//   where sometimes it uses <var1> and sometimes <var2>.  Since we don't
> > > +//   treat the code above (with overlapping components) as an error, it
> > > +//   would be strange to treat non-overlapping component assignments as an
> > > +//   error."
> > > +
> > > +#version 150
> > > +#extension GL_ARB_enhanced_layouts: require
> > > +#extension GL_ARB_explicit_attrib_location: require
> > > +#extension GL_ARB_gpu_shader_fp64: require
> > > +#extension GL_ARB_vertex_attrib_64bit: require
> > > +
> > > +uniform int i;
> > > +
> > > +// consume X/Y components
> > > +layout(location = 0) in ivec2 a;
> > > +
> > > +// consume Z/W components
> > > +layout(location = 0, component = 2) in double b;
> > > +
> > > +void main()
> > > +{
> > > +  if (i == 1)
> > > +    gl_Position = vec4(a, 1.0, 1.0);
> > > +  else
> > > +    gl_Position = vec4(b);
> > > +}
> > > diff --git a/tests/spec/arb_enhanced_layouts/compiler/component-layout/width-mismatch-float-double.vert b/tests/spec/arb_enhanced_layouts/compiler/component-layout/width-mismatch-float-double.vert
> > > new file mode 100644
> > > index 000000000..74926c1ea
> > > --- /dev/null
> > > +++ b/tests/spec/arb_enhanced_layouts/compiler/component-layout/width-mismatch-float-double.vert
> > > @@ -0,0 +1,59 @@
> > > +// [config]
> > > +// expect_result: pass
> > > +// glsl_version: 1.50
> > > +// check_link: true
> > > +// require_extensions: GL_ARB_enhanced_layouts GL_ARB_explicit_attrib_location GL_ARB_gpu_shader_fp64 GL_ARB_vertex_attrib_64bit
> > > +// [end config]
> > > +//
> > > +// From Section 4.4.1 (Input Layout Qualifiers) of the GLSL 4.60 spec:
> > > +//
> > > +//   "Further, when location aliasing, the aliases sharing the
> > > +//    location must have the same underlying numerical type and bit
> > > +//    width (floating-point or integer, 32-bit versus 64-bit, etc.)
> 
> This directly contradicts the example just above this text:
> 
>  From section 4.4.1 (Input Layout Qualifiers) of the GLSL 4.6 spec:
> 
> "layout(location=8) in dvec3 h; // components 0,1,2 and 3 of location 8
>                                  // and components 0 and 1 of location 9
>   layout(location=9, component=2) in float i; // okay, compts 2 and 3"

See my answer at:
https://lists.freedesktop.org/archives/mesa-dev/2019-March/216979.html


> > > +//    and the same auxiliary storage and interpolation
> > > +//    qualification. The one exception where component aliasing is
> > > +//    permitted is for two input variables (not block members) to a
> > > +//    vertex shader, which are allowed to have component
> > > +//    aliasing. This vertex-variable component aliasing is intended
> > > +//    only to support vertex shaders where each execution path
> > > +//    accesses at most one input per each aliased
> > > +//    component. Implementations are permitted, but not required, to
> > > +//    generate link-time errors if they detect that every path through
> > > +//    the vertex shader executable accesses multiple inputs aliased to
> > > +//    any single component."
> > > +//
> > > +//   Issue 16 from the ARB_enhanced_layouts spec:
> > > +//
> > > +//   "We do allow this for vertex shader inputs, because we've supported
> > > +//   "aliasing" behavior since OpenGL 2.0. This allows for an "uber-shader"
> > > +//    with variables like:
> > > +//
> > > +//          layout(location=3) in float var1;
> > > +//          layout(location=3) in int var2;
> > > +//
> > > +//   where sometimes it uses <var1> and sometimes <var2>.  Since we don't
> > > +//   treat the code above (with overlapping components) as an error, it
> > > +//   would be strange to treat non-overlapping component assignments as an
> > > +//   error."
> > > +
> > > +#version 150
> > > +#extension GL_ARB_enhanced_layouts: require
> > > +#extension GL_ARB_explicit_attrib_location: require
> > > +#extension GL_ARB_gpu_shader_fp64: require
> > > +#extension GL_ARB_vertex_attrib_64bit: require
> > > +
> > > +uniform int i;
> > > +
> > > +// consume X/Y components
> > > +layout(location = 0) in vec2 a;
> > > +
> > > +// consume Z/W components
> > > +layout(location = 0, component = 2) in double b;
> > > +
> > > +void main()
> > > +{
> > > +  if (i == 1)
> > > +    gl_Position = vec4(a, 1.0, 1.0);
> > > +  else
> > > +    gl_Position = vec4(b);
> > > +}
> > > diff --git a/tests/spec/arb_enhanced_layouts/linker/component-layout/vs-to-fs-type-mismatch-double-float.shader_test b/tests/spec/arb_enhanced_layouts/linker/component-layout/vs-to-fs-width-mismatch-double-float.shader_test
> > > similarity index 56%
> > > rename from tests/spec/arb_enhanced_layouts/linker/component-layout/vs-to-fs-type-mismatch-double-float.shader_test
> > > rename to tests/spec/arb_enhanced_layouts/linker/component-layout/vs-to-fs-width-mismatch-double-float.shader_test
> > > index ed596b3dc..fefff6d78 100644
> > > --- a/tests/spec/arb_enhanced_layouts/linker/component-layout/vs-to-fs-type-mismatch-double-float.shader_test
> > > +++ b/tests/spec/arb_enhanced_layouts/linker/component-layout/vs-to-fs-width-mismatch-double-float.shader_test
> > > @@ -1,16 +1,17 @@
> > > -// From Section 4.4.1 (Input Layout Qualifiers) of the GLSL 4.50 spec:
> > > +// From Section 4.4.1 (Input Layout Qualifiers) of the GLSL 4.60 spec:
> > >   //
> > > -//   "Location aliasing is causing two variables or block members to have the
> > > -//   same location number. Component aliasing is assigning the same (or
> > > -//   overlapping) component numbers for two location aliases. (Recall if
> > > -//   component is not used, components are assigned starting with 0.) With one
> > > -//   exception, location aliasing is allowed only if it does not cause
> > > -//   component aliasing; it is a compile-time or link-time error to cause
> > > -//   component aliasing."
> > > -//
> > > -//   "Further, when location aliasing, the aliases sharing the location must
> > > -//   have the same underlying numerical type (floating-point or integer) and
> > > -//   the same auxiliary storage and interpolation qualification"
> > > +//   "Location aliasing is causing two variables or block members to
> > > +//    have the same location number. Component aliasing is assigning
> > > +//    the same (or overlapping) component numbers for two location
> > > +//    aliases. (Recall if component is not used, components are
> > > +//    assigned starting with 0.) With one exception, location aliasing
> > > +//    is allowed only if it does not cause component aliasing; it is a
> > > +//    compile-time or link-time error to cause component
> > > +//    aliasing. Further, when location aliasing, the aliases sharing
> > > +//    the location must have the same underlying numerical type and
> > > +//    bit width (floating-point or integer, 32-bit versus 64-bit,
> > > +//    etc.) and the same auxiliary storage and interpolation
> > > +//    qualification."
> > >   
> > >   [require]
> > >   GLSL >= 1.50
> > 
> > _______________________________________________
> > Piglit mailing list
> > Piglit at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/piglit
> > 
-- 
Br,

Andres



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