glsl: improve accuracy of atan()

Our current atan()-approximation is pretty inaccurate at 1.0, so
let's try to improve the situation by doing a direct approximation
without going through atan.

This new implementation uses an 11th degree polynomial to approximate
atan in the [-1..1] range, and the following identitiy to reduce the
entire range to [-1..1]:

atan(x) = 0.5 * pi * sign(x) - atan(1.0 / x)

This range-reduction idea is taken from the paper "Fast computation
of Arctangent Functions for Embedded Applications: A Comparative
Analysis" (Ukil et al. 2011).

The polynomial that approximates atan(x) is:

x   * 0.9999793128310355 - x^3  * 0.3326756418091246 +
x^5 * 0.1938924977115610 - x^7  * 0.1173503194786851 +
x^9 * 0.0536813784310406 - x^11 * 0.0121323213173444

This polynomial was found with the following GNU Octave script:

x = linspace(0, 1);
y = atan(x);
n = [1, 3, 5, 7, 9, 11];
format long;
polyfitc(x, y, n)

The polyfitc function is not built-in, but too long to include here.
It can be downloaded from the following URL:

http://www.mathworks.com/matlabcentral/fileexchange/47851-constraint-polynomial-fit/content/polyfitc.m

This fixes the following piglit test:
shaders/glsl-const-folding-01

Signed-off-by: Erik Faye-Lund <kusmabite@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
ilo: disassemble compacted instructions

Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
gallium: Add tokens for DragonFly BSD.

Signed-off-by: Vinson Lee <vlee@freedesktop.org>
Acked-by: Brian Paul <brianp@vmware.com>
clover: Use unreachable() from util/macros.h instead of assert(0).

Reviewed-by: Francisco Jerez <currojerez@riseup.net>
clover: Add semantic information to module::argument for implicit parameter passing.

Reviewed-by: Jan Vesely <jan.vesely@rutgers.edu>
clover: Pass execution dimensions and offset to the kernel as implicit arguments.

Reviewed-by: Jan Vesely <jan.vesely@rutgers.edu>
clover: Append implicit arguments to the kernel argument list.

[ Francisco Jerez: Split off from a larger patch, and take a slightly
  different approach for passing the implicit arguments around. ]

Reviewed-by: Francisco Jerez <currojerez@riseup.net>
tgsi/ureg: add ureg_UARL shortcut
mesa/gallium: API settings / rasterization rules

Signed-off-by: David Heidelberger <david.heidelberger@ixit.cz>
radeon/softpipe/llvmpipe/svga/i915/ilo/freedreno/nv30: use API settings / rasterization rules

v2: compilation fixes by David Heidelberger <david.heidelberger@ixit.cz>
v3: compilation fix by Thermionix <bond711@gmail.com>

Signed-off-by: David Heidelberger <david.heidelberger@ixit.cz>
nvc0: improve code readability

Signed-off-by: David Heidelberger <david.heidelberger@ixit.cz>
nv50/nvc0: use API settings / rasterization rules

Signed-off-by: David Heidelberger <david.heidelberger@ixit.cz>
nvc0: fix incorrect flipping

This change fixes few OpenGL apps.

Signed-off-by: Tiziano Bacocco <tizbac2@gmail.com>
nv50,nvc0: handle TGSI_PROPERTY_VS_WINDOW_SPACE_POSITION
nv50,nvc0: handle NULL vertex elements without fallback
nv50/ir/tgsi: implement TGSI_OPCODE_NRM,DP2A

Used by d3d9 st.
hack/nv50: don't emit buffer for skipped vertex elements

Grr, should forbid that and insert dummy elements in nine.
hack/nvc0: avoid fault in get_query_result if there was no begin_query
winsys/sw/wrapper: hook up is_displaytarget_format_supported

Looks like no one's using this thing.
gallium/draw: support hack to disable clipping