i965/vec4: Add non-mutating helper functions to modify src_reg::swizzle and ::negate.

Reviewed-by: Paul Berry <stereotype441@gmail.com>
(cherry picked from commit 98306e727b8291507ff4fd5dd5c4806f3fed9202)
i965/vec4: Add a brw->gen >= 6 assertion in three-source emitters.

Three source instructions didn't exist until Gen6.  vec4_generator has
assertions to catch this, but catching it in the visitor provides a
nicer backtrace.

Cc: "10.1" <mesa-stable@lists.freedesktop.org>
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Acked-by: Eric Anholt <eric@anholt.net>
(cherry picked from commit ffde483f3c4da547f2823f72554cea1d1ff25e48)
i965/vec4: Handle ir_triop_lrp on Gen4-5 as well.

When the vec4 backend encountered an ir_triop_lrp, it always emitted an
actual LRP instruction, which only exists on Gen6+.  Gen4-5 used
lower_instructions() to decompose ir_triop_lrp at the IR level.

Since commit 8d37e9915a3b21 ("glsl: Optimize open-coded lrp into lrp."),
we've had an bug where lower_instructions translates ir_triop_lrp into
arithmetic, but opt_algebraic reassembles it back into a lrp.

To avoid this ordering concern, just handle ir_triop_lrp in the backend.
The FS backend already does this, so we may as well do likewise.

v2: Add a comment reminding us that we could emit better assembly if we
    implemented the infrastructure necessary to support using MAC.
    (Assembly code provided by Eric Anholt).

Cc: "10.1" <mesa-stable@lists.freedesktop.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=75253
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Acked-by: Eric Anholt <eric@anholt.net>
(cherry picked from commit 56879a7ac41b8c7513a97cc02921f76a2ec8407c)
i965: Stop lowering ir_triop_lrp.

Both the vector and scalar backends now support it natively, so there's
no point in lowering it.

Cc: "10.1" <mesa-stable@lists.freedesktop.org>
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Acked-by: Eric Anholt <eric@anholt.net>
(cherry picked from commit 2fdea48e21c48f4543e1239787d34cf84ab96959)
glsl: Delete LRP_TO_ARITH lowering pass flag.

Tt's kind of a trap---calling do_common_optimization() after
lower_instructions() may cause opt_algebraic() to reintroduce
ir_triop_lrp expressions that were lowered, effectively defeating the
point.  Because of this, nobody uses it.

v2: Delete more code (caught by Ian Romanick).

Cc: "10.1" <mesa-stable@lists.freedesktop.org>
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Acked-by: Eric Anholt <eric@anholt.net>
(cherry picked from commit ac0a8b9540b29eb6faa55e4c77ba8fa99478884a)
i965: Don't try to dump shader source for fixed-function FS programs.

sh->Source is NULL and this will segfault.

Fixes MESA_GLSL=dump with "The Swapper".

Cc: mesa-stable@lists.freedesktop.org
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
(cherry picked from commit f896e82301255177894a6c51883e18d32c36b307)
i965: Fix the region's pitch condition to use blitter

intelEmitCopyBlit uses a signed 16-bit integer to represent
buffer pitch, so it can only handle buffer pitches < 32k.

Cc: mesa-stable@lists.freedesktop.org
Signed-off-by: Anuj Phogat <anuj.phogat@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
(cherry picked from commit b3094d9927fe7aa5a84892262404aaad4d728724)