[Impeller] remove emulation of clamp, repeat, and mirror tile modes

[jonahwilliams]

Most tile modes can be implemented entirely with the addressing mode. Removing the other branches improves performance

Malioc Diff:

Changes found in shader flutter/impeller/entity/gles/tiled_texture_fill.frag.gles on core Mali-G78:
In variant Main:
  fp16_arithmetic: 100 <- before
  fp16_arithmetic: 33 <- after
longest_path_cycles in variant Main
        arith_total arith_fma   arith_cvt   arith_sfu   load_store  varying     texture     bound       
before  0.500000    0.203125    0.500000    0.000000    0.000000    0.125000    0.250000    arith_total,arith_cvt
after   0.265625    0.031250    0.265625    0.000000    0.000000    0.250000    0.250000    arith_total,arith_cvt

shortest_path_cycles in variant Main
        arith_total arith_fma   arith_cvt   arith_sfu   load_store  varying     texture     bound       
before  0.109375    0.031250    0.109375    0.000000    0.000000    0.125000    0.000000    varying
after   0.062500    0.031250    0.062500    0.000000    0.000000    0.250000    0.250000    varying,texture

total_cycles in variant Main
        arith_total arith_fma   arith_cvt   arith_sfu   load_store  varying     texture     bound       
before  0.625000    0.265625    0.625000    0.000000    0.000000    0.125000    0.250000    arith_total,arith_cvt
after   0.265625    0.031250    0.265625    0.000000    0.000000    0.250000    0.250000    arith_total,arith_cvt

In variant Main:
  uniform_registers_used: 8 <- before
  uniform_registers_used: 4 <- after

For a full report, run:
  $ malioc --fragment --core Mali-G78 /b/s/w/ir/cache/builder/src/out/android_debug_unopt/gen/flutter/impeller/entity/gles/tiled_texture_fill.frag.gles

Changes found in shader flutter/impeller/entity/gles/tiled_texture_fill.frag.gles on core Mali-T880:
longest_path_cycles in variant Main
        arithmetic  load_store  texture     bound       
before  7.920000    1.000000    1.000000    arithmetic
after   3.300000    1.000000    1.000000    arithmetic

total_cycles in variant Main
        arithmetic  load_store  texture     bound       
before  9.666667    1.000000    1.000000    arithmetic
after   3.666667    1.000000    1.000000    arithmetic


For a full report, run:
  $ malioc --fragment --core Mali-T880 /b/s/w/ir/cache/builder/src/out/android_debug_unopt/gen/flutter/impeller/entity/gles/tiled_texture_fill.frag.gles

Changes found in shader flutter/impeller/entity/gles/tiled_texture_fill.vert.gles on core Mali-G78:
In variant Position:
  uniform_registers_used: 24 <- before
  uniform_registers_used: 22 <- after
In variant Varying:
  fp16_arithmetic: 18 <- before
  fp16_arithmetic: 100 <- after
longest_path_cycles in variant Varying
        arith_total arith_fma   arith_cvt   arith_sfu   load_store  texture     bound       
before  0.156250    0.156250    0.000000    0.062500    3.000000    0.000000    load_store
after   0.125000    0.125000    0.031250    0.062500    3.000000    0.000000    load_store

shortest_path_cycles in variant Varying
        arith_total arith_fma   arith_cvt   arith_sfu   load_store  texture     bound       
before  0.156250    0.156250    0.000000    0.062500    3.000000    0.000000    load_store
after   0.125000    0.125000    0.031250    0.062500    3.000000    0.000000    load_store

total_cycles in variant Varying
        arith_total arith_fma   arith_cvt   arith_sfu   load_store  texture     bound       
before  0.156250    0.156250    0.000000    0.062500    3.000000    0.000000    load_store
after   0.125000    0.125000    0.031250    0.062500    3.000000    0.000000    load_store

In variant Varying:
  uniform_registers_used: 18 <- before
  uniform_registers_used: 16 <- after
In variant Varying:
  work_registers_used: 9 <- before
  work_registers_used: 8 <- after

For a full report, run:
  $ malioc --vertex --core Mali-G78 /b/s/w/ir/cache/builder/src/out/android_debug_unopt/gen/flutter/impeller/entity/gles/tiled_texture_fill.vert.gles

[flutter-dashboard]

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