mesa: implement missing glGet(GL_RGBA_SIGNED_COMPONENTS_EXT) query

This is part of the GL_EXT_packed_float extension.

  Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
  Reviewed-by: Chris Forbes <chrisf@ijw.co.nz>
  (cherry picked from commit 3486f6f31b8cdb01e480cfbd8814c1e4222d26b0

Also squashed in a subsequent bug fix:

  mesa: check for MESA_FORMAT_RGB9_E5_FLOAT in _mesa_is_format_signed()

  This packed floating point format only stores positive values.

  Reviewed-by: Marek Olšák <marek.olsak@amd.com>
  Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
  Reviewed-by: Roland Scheidegger <sroland@vmware.com>
  (cherry picked from commit 0fc8d7c66e08c295b701586afdc1f6d86eb8a514)

Also squashed in a second, subsequent bug fix:

  mesa: check bits per channel for GL_RGBA_SIGNED_COMPONENTS_EXT query

  If a channel has zero bits it's not signed.

  v2: also check for luminance and intensity format bits.  Bruce
  Merry's proposed piglit test hits the luminance case.

  Reviewed-by: Matt Turner <mattst88@gmail.com>
  (cherry picked from commit d046fd731ab192dceee0916323dd718b78df5976)

Bugzilla: http://bugs.freedesktop.org/show_bug.cgi?id=73096
Cc: 10.0 <mesa-stable@lists.freedesktop.org>

Conflicts:
	src/mesa/main/get.c
swrast: fix delayed texel buffer allocation regression for OpenMP

Commit 9119269ca14ed42b51c7d8e2e662500311b29fa3 moved the texel
buffer allocation to _swrast_texture_span(), however, when compiled
with OpenMP support this code already runs multi-threaded so a
critical section is required to prevent multiple allocations and
rendering errors.

Cc: "10.0" <mesa-stable@lists.freedesktop.org>
Reviewed-by: Brian Paul <brianp@vmware.com>
(cherry picked from commit 2a0fb946e147f5482c93702fbf46ffdf5208f57c)
i965: fold offset into coord for textureOffset(gsampler2DRect)

The hardware is broken with nonzero texel offsets and unnormalized
coordinates; instead of doing correct offsetting, we get garbage.

This just extends the existing workaround for ir_txf and
ir_tg4+gsampler2DRect to also consider ir_tex+gsampler2DRect.

Fixes broken rendering in 'tesseract' when 'mesa_texrectoffset_bug' is
not enabled; also fixes the new piglit test
'tests/spec/glsl-1.30/execution/fs-textureOffset-Rect'.

Has been broken ~forever; suggesting including this in only 10.0 because
the lowering pass doesn't exist in 9.2 or earlier so would require quite
a different patch.

Signed-off-by: Chris Forbes <chrisf@ijw.co.nz>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Cc: Lee Salzman <lsalzman@gmail.com>
Cc: "10.0" <mesa-stable@lists.freedesktop.org>
(cherry picked from commit 9e99735f301ebf85f8d0bfdce2bad441a5aac7f8)
mesa: Preliminary support for MSVC_VERSION=12.0

Cc: "10.0" <mesa-stable@lists.freedesktop.org>
Reviewed-by: Brian Paul <brianp@vmware.com>
(cherry picked from commit 20e65c92c760404560be629354999314632f8674)
mesa: Fix compile error with MSVC 2013

This fixes the following compile error:
src\glsl\ir_constant_expression.cpp(1405) : error C2666: 'copysign' : 3
overloads have similar conversions

Cc: "10.0" <mesa-stable@lists.freedesktop.org>
Reviewed-by: Brian Paul <brianp@vmware.com>
(cherry picked from commit 067ad6e53ec2545970b7698d06d2a537da194678)
mesa: Work around internal compiler error

This small rearrangement avoids MSVC 2013 ICE. Also, this should be
a better memory access order.

Cc: "10.0" <mesa-stable@lists.freedesktop.org>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
(cherry picked from commit 8fcddd325ce3dc5dfdafc95767542590ae860c45)
mesa: Namespace qualify fma to override ambiguity with fma from math.h

MSVC 2013 version of math.h includes an fma() function.

Cc: "10.0" <mesa-stable@lists.freedesktop.org>
Reviewed-by: Brian Paul <brianp@vmware.com>
(cherry picked from commit e8ff08edd823ddf6b0e07ef84d2ba8afc3abbc34)
i965: Fix handling of MESA_pack_invert in blit (PBO) readpixels.

Fixes piglit GL_MESA_pack_invert/readpixels and GPU hangs with glamor and
cairo-gl.

Cc: 10.0 9.2 <mesa-stable@lists.freedesktop.org>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Anuj Phogat <anuj.phogat@gmail.com>
(cherry picked from commit e186b927b8254ce62e0d47db90d16cd4253b3db5)
i965: Don't do the temporary-and-blit-copy for INVALIDATE_RANGE maps.

We definitely want to fall through to the unsynchronized map case, instead
of wasting bandwidth on a copy.  Prevents a -43.2407% +/- 1.06113% (n=49)
performance regression on aa10perf when teaching glamor to provide the
GL_INVALIDATE_RANGE_BIT information.

This is a performance fix, which I usually wouldn't cherry-pick to stable.
But this was really was just a bug in the code, its presence would
discourage developers from giving us the best information they can, and I
think we've got fairly high confidence in the unsynchronized map path
already.

Cc: 10.0 9.2 <mesa-stable@lists.freedesktop.org>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
(cherry picked from commit f46563fe1c8a5560e4de0adf03e3d8770b7fc734)