[Bug 90158] New: Make shader precompile guess MSAA layout properly

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=90158

            Bug ID: 90158
           Summary: Make shader precompile guess MSAA layout properly
           Product: Mesa
           Version: git
          Hardware: Other
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: medium
         Component: Drivers/DRI/i965
          Assignee: idr at freedesktop.org
          Reporter: kenneth at whitecape.org
        QA Contact: intel-3d-bugs at lists.freedesktop.org
            Blocks: 77547

Currently, brw_fs_precompile doesn't set compressed_multisample_layout_mask,
leaving it at the default value of 0 (non-CMS).

This is dumb.  Virtually all multisampled color buffers on Gen7+ use the CMS
layout, not UMS or IMS.  So, basically every shader that uses a sampler2DMS
type (including most of WebGL) will require a recompile.

A better guess would be:
- 1 for sampler2DMS on Gen7+ (0 on Gen6)
- 0 for sampler2DMSShadow
- 0 for non-MS sampler types.

This should eliminate almost all recompiles due to
compressed_multisample_layout_mask.

To accomplish this, we may want to create a bitfield similar to SamplersUsed or
ShadowSamplers...SamplerIsMSAA or such.  Then the precompile could easily check
it.  Alternatively, we could stop using bitfields and walk a list of NIR
uniforms.  It should be pretty simple.

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freedesktop.org/archives/intel-3d-bugs/attachments/20150424/a3db74d2/attachment.html>