i965: Add an env var for forcing window system MSAA.

Sometimes it would be nice to benchmark some app with MSAA versus not, but
it doesn't offer the controls you want.  Just provide a handy knob to
force the issue.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
i965: Don't forget to free the old singlesample_mt.

Fixes a memory leak with MSAA winsys buffers since my move of
singlesample_mt to the rb in 4e0924c5de5f3964e4ca81f923d877dbb59fad0a

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
i965: Simplify the no-reopening-the-winsys-buffer tests.

The formatting was weird, and the tests were duplicated, and it is
guaranteed that mt->region exists.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
i965: Skip reallocating the private MSAA miptree, unless it's resized.

Even if the singlesample_mt got reopened from DRI due to
pageflipping/buffer swapping, our private miptree shouldn't need any
changes.

Improves performance of a little swapbuffers-loving microbenchmark with
MSAA forced on, by 1.2371% +/- 0.624802% (n=102)

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
mesa: Stop skipping the FinishRenderTexture calls for winsys FBOs.

Now that BindRenderbufferTexImage() is a thing that drivers can do, winsys
FBOs *can* have NeedsFinishRenderTexture set.

v2: Keep the short-circuit for non-BindRenderbufferTexImage() drivers
    (review by Ken).

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
i965/gen8: Change the winsys MSAA blits from blorp to meta.

This gets us equivalent code paths on BDW and pre-BDW, except for stencil
(where we don't have MSAA stencil resolve code yet)

Improves MSAA-forced citybench by 7.94496% +/- 2.38429% (n=16).  Reduces
DRI2 MSAA glxgears performance by -12.3559% +/- 1.52845% (n=9).

v2: Move the new meta code to brw_meta_updownsample.c, name it
    brw_meta_updownsample(), add a comment about
    intel_rb_storage_first_mt_slice(), and rename that function and move
    the RB generation into it (review ideas by Ken).
v3: Fix 2 src vs dst pasteos in previous change.
v4: Skip this path pre-gen8 for now, until we can analyze the glxgears
    performance delta some more.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
i965: Fix compiler warning about signed/unsigned.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
mesa: Introduce a _mesa_format_has_color_component() helper.

When considering color write masks, we often want to know whether an
RGBA component actually contains any meaningful data.  This function
provides an easy way to answer that question, and handles luminance,
intensity, and alpha formats correctly.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Tested-by: Dylan Baker <baker.dylan.c@gmail.com>
mesa: Skip clearing color buffers when color writes are disabled.

WebGL Aquarium in Chrome 24 actually hits this.

v2: Move to core Mesa (wisely suggested by Ian); only consider
    components which actually exist.

v3: Use _mesa_format_has_color_component to determine whether components
    actually exist, fixing alpha format handling.

v4: Add a comment, as requested by Brian.  No actual code changes.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Tested-by: Dylan Baker <baker.dylan.c@gmail.com>
i965: For color clears, only disable writes to components that exist.

The SIMD16 replicated FB write message only works if we don't need the
color calculator to mask our framebuffer writes.  Previously, we bailed
on it if color_mask wasn't <true, true, true, true>.  However, this was
needlessly strict for formats with fewer than four components - only the
components that actually exist matter.

WebGL Aquarium attempts to clear a BGRX texture with the ColorMask set
to <true, true, true, false>.  This will work perfectly fine with the
replicated data message; we just bailed unnecessarily.

Improves performance of WebGL Aquarium on Iris Pro (at 1920x1080) by
abound 50%, and Bay Trail (at 1366x768) by over 70% (using Chrome 24).

v2: Use _mesa_format_has_color_component() to properly handle ALPHA
    formats (and generally be less fragile).

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Tested-by: Dylan Baker <baker.dylan.c@gmail.com>
haiku: Fix build through scons corrections and viewport fixes

* Add HAVE_PTHREAD, we do have pthread support wrappers now for
  non-native Haiku threaded applications.
* Viewport changed behavior recently breaking the build.
  We fix this by looking at the gl_context ViewportArray
  (Thanks Brian for the idea)

Acked-by: Brian Paul <brianp@vmware.com>
draw: Duplicate TGSI tokens in draw_pipe_pstipple module.

As done in draw_pipe_aaline and draw_pipe_aapoint modules.

Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Roland Scheidegger <sroland@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
Cc: "10.0 10.1" <mesa-stable@lists.freedesktop.org>
llvmpipe: Simplify vertex and geometry shaders.

Eliminate lp_vertex_shader, as it added nothing over draw_vertex_shader.

Simplify lp_geometry_shader, as most of the incoming state is unneeded.
(We could also just use draw_geometry_shader if we were willing to peek
inside the structure.)

Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Roland Scheidegger <sroland@vmware.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
mesa/sso: replace Shader binding point with _Shader

To avoid NULL pointer check a default pipeline object is installed in
_Shader when no program is current

The spec say that UseProgram/UseShaderProgramEXT/ActiveProgramEXT got an
higher priority over the pipeline object. When default program is
uninstall, the pipeline is used if any was bound.

Note: A careful rename need to be done now...

V2: formating improvement

V3 (idr):
* Build fix.  The original patch added calls to _mesa_use_shader_program
  with 4 parameters, but the fourth parameter isn't added to that
  function until a much later patch.  Just drop that parameter for now.
* Trivial reformatting.
* Updated comment of gl_context::_Shader

v4 (idr): Reformat spec quotations to look like spec quotations.  Update
comments describing what gl_context::_Shader can point to.  Bot
suggested by Eric.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
mesa/sso: rename Shader to the pointer _Shader

Basically a sed but shaderapi.c and get.c.
get.c => GL_CURRENT_PROGAM always refer to the "old" UseProgram behavior
shaderapi.c => the old api stil update the Shader object directly

V2: formatting improvement

V3 (idr):
* Rebase fixes after a block of code was moved from ir_to_mesa.cpp to
  shaderapi.c.
* Trivial reformatting.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
meta/sso: Update meta to save and restore SSO state.

save and restore _Shader/Pipeline binding point. Rational we don't want any
conflict when the program will be unattached.

V2: formatting improvement

V3 (idr):
* Build fix.  The original patch added calls to _mesa_use_shader_program
  with 4 parameters, but the fourth parameter isn't added to that
  function until a much later patch.  Just drop that parameter for now.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
mesa/sso: Add gl_pipeline_object parameter to _mesa_use_shader_program

Extend use_shader_program to support a different target. Allow to reuse the
function to update the pipeline state. Note I bypass the flush when target
isn't current. Maybe it would be better to create a new UseProgramStages
driver function

This was originally included in another patch, but it was split out by
Ian Romanick.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
mesa/sso: Implement _mesa_UseProgramStages

Now arb_separate_shader_object-GetProgramPipelineiv should pass.

V3 (idr):
* Change spec references to core OpenGL versions instead of issues in
  the extension spec.
* Split out from previous uber patch.

v4 (idr): Use _mesa_has_geometry_shaders in _mesa_UseProgramStages to
detect availability of geometry shaders.

v5 (idr): Whitespace cleanup, use _mesa_lookup_shader_program_err
instead of open-coding it again, and update some comments at the end of
_mesa_UseProgramStages.  All suggested by Eric.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
mesa/sso: Implement _mesa_BindProgramPipeline

Test become green in piglit:

The updated ext_transform_feedback-api-errors:useprogstage_noactive useprogstage_active bind_pipeline
arb_separate_shader_object-GetProgramPipelineiv
arb_separate_shader_object-IsProgramPipeline

For the moment I reuse Driver.UseProgram but I guess it will be better
to create a UseProgramStages functions. Opinion is welcome

V2: formatting & rename

V3 (idr):
* Change spec references to core OpenGL versions instead of issues in the
  extension spec.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
mesa/sso: Implement GL_PROGRAM_PIPELINE_BINDING for glGet

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Eric Anholt <eric@anholt.net>