glsl: Size TCS->TES unsized arrays to gl_MaxPatchVertices for queries.

SSO validation and other program interface queries want to see that
unsized (non-patch) TCS output/TES input arrays are implicitly sized
to gl_MaxPatchVertices.

By the time we create the program resource lists, we've sized the arrays
to their actual size.  (We try to create TCS output arrays to match the
output patch size right away, and at this point, we should have shrunk
TES input arrays.)  One option would be to keep them sized to
gl_MaxPatchVertices, and defer shrinking them.  But that's a big change,
and I don't think it's a good idea.

Instead, this patch introduces a new ir_variable flag which indicates
the variable is implicitly to gl_MaxPatchVertices.  Then, the linker
munges the types when creating the resource list, ignoring the size
in the IR's types.  Basically, lie about it for resource queries.
It's ugly, but I think it ought to work.

We probably could use var->data.implicit_sized_array for this, but
I opted for a separate bit to try and avoid convoluting the existing
SSBO handling.  They're similar in concept, but share none of the
same code...

Fixes:
ES31-CTS.core.tessellation_shader.single.xfb_captures_data_from_correct_stage
and the ES32-CTS and ESEXT-CTS variants.

v2: Add a comment (requested by Timothy, written by me).

Cc: mesa-stable@lists.freedesktop.org
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Timothy Arceri <timothy.arceri@collabora.com>
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
(cherry picked from commit 173558445dce26ce641faf260a17696221acf23d)

1 files changed, 6 insertions, 0 deletions

diff --git a/src/compiler/glsl/ir.h b/src/compiler/glsl/ir.h
index 3d28dd5..f07e3b2 100644
--- a/src/compiler/glsl/ir.h
+++ b/src/compiler/glsl/ir.h
@@ -833,6 +833,12 @@ public:
       unsigned implicit_sized_array:1;
 
       /**
+       * Is this a non-patch TCS output / TES input array that was implicitly
+       * sized to gl_MaxPatchVertices?
+       */
+      unsigned tess_varying_implicit_sized_array:1;
+
+      /**
        * Whether this is a fragment shader output implicitly initialized with
        * the previous contents of the specified render target at the
        * framebuffer location corresponding to this shader invocation.