intel/compiler: Clear accumulator register before EOT

v2: (Francisco Jerez)
- Drop vec4 changes.
- Handle explicit acc0 operand and implicit one.
- Make sure instruction is SIMD16, prediction is off and default mask
  control set to true.

v3: (Francisco Jerez)
- Clear accumulator only when it's written.
- Use BRW_MASK_DISABLE instead of true.
- Use correct width for brw_acc_reg().
- Fix last_inst_offset.

v4: (Francisco Jerez)
- Don't check for last instruction for accummulator write.

Signed-off-by: Sagar Ghuge <sagar.ghuge@intel.com>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Tested-by: Marge Bot <mesa/mesa!3376>
Part-of: <mesa/mesa!3376>
38 jobs for !3376 with review/accum_clear_wa in 28 minutes and 6 seconds (queued for 10 seconds)
detached
Status Job ID Name Coverage
  Container
passed #1474580
aarch64
arm_build

00:00:20

passed #1474581
aarch64
arm_test

00:00:21

passed #1474577
x86_build

00:00:21

passed #1474579
x86_build_old

00:00:23

passed #1474578
x86_test-gl

00:00:39

 
  Build
passed #1474585
aarch64
meson-arm64

00:11:50

passed #1474584
aarch64
meson-armhf

00:02:52

passed #1474586
meson-clang

00:08:29

passed #1474589
meson-clover

00:07:00

passed #1474590
meson-clover-old-llvm

00:03:29

passed #1474592
meson-i386

00:00:52

passed #1474583
meson-main

00:03:10

passed #1474593
meson-mingw32-x86_64

00:05:44

passed #1474582
meson-testing

00:07:14

passed #1474591
meson-vulkan

00:06:33

passed #1474594
scons

00:05:43

passed #1474595
scons-old-llvm

00:06:46

passed #1474587
scons-swr

00:04:46

passed #1474588
scons-win64

00:02:57

 
  Test
passed #1474614
db410c
arm64_a306_gles2

00:07:37

passed #1474611
mesa-cheza
arm64_a630_gles2

00:01:51

passed #1474613
mesa-cheza
arm64_a630_gles3

00:06:38

passed #1474612
mesa-cheza
arm64_a630_gles31

00:04:27

passed #1474599
lava-meson-gxl-s905x-libretech-cc
lima-mali450-test:arm64

00:15:06

passed #1474596
lava-sun50i-h6-pine-h64
panfrost-t720-test:arm64

00:08:10

passed #1474597
lava-rk3288-veyron-jaq
panfrost-t760-test:armhf

00:07:16

passed #1474598
lava-rk3399-gru-kevin
panfrost-t860-test:arm64

00:12:09

passed #1474601
piglit-glslparser

00:02:48

passed #1474600
piglit-quick_gl

00:14:11

passed #1474602
piglit-quick_shader

00:07:32

passed #1474603
test-llvmpipe-gles2

00:02:42

passed #1474604
test-softpipe-gles2

00:02:20

passed #1474607
test-softpipe-gles31 1/4

00:04:36

passed #1474605
test-softpipe-gles3 1/2

00:04:08

passed #1474608
test-softpipe-gles31 2/4

00:04:47

passed #1474609
test-softpipe-gles31 3/4

00:06:57

passed #1474610
test-softpipe-gles31 4/4

00:02:47

passed #1474606
test-softpipe-gles3 2/2

00:07:32