Module: Mesa Branch: main Commit: a147717a93d912df7aa25cde2bdfd869eb67843d URL: http://cgit.freedesktop.org/mesa/mesa/commit/?id=a147717a93d912df7aa25cde2bdfd869eb67843d
Author: Ian Romanick <[email protected]> Date: Tue Jan 26 19:51:57 2021 -0800 nir/algebraic: Optimize some extract forms resulting from 8-bit lowering This eliminates some spurious, size-converting moves. For example, on Ice Lake this helps dEQP-VK.spirv_assembly.type.vec3.i8.bitwise_xor_frag: SIMD8 shader: 56 instructions. 1 loops. 4444 cycles. 0:0 spills:fills, 5 sends SIMD8 shader: 52 instructions. 1 loops. 4164 cycles. 0:0 spills:fills, 5 sends v2: Condition two of the patterns on !options->lower_extract_byte. Suggested by Lionel. Reviewed-by: Lionel Landwerlin <[email protected]> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9025> --- src/compiler/nir/nir_opt_algebraic.py | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/src/compiler/nir/nir_opt_algebraic.py b/src/compiler/nir/nir_opt_algebraic.py index 376069514c3..1bf08ee3214 100644 --- a/src/compiler/nir/nir_opt_algebraic.py +++ b/src/compiler/nir/nir_opt_algebraic.py @@ -1253,6 +1253,15 @@ optimizations.extend([ (('ishr', 'a@64', 56), ('extract_i8', a, 7), '!options->lower_extract_byte'), (('iand', 0xff, a), ('extract_u8', a, 0), '!options->lower_extract_byte'), + # Common pattern in many Vulkan CTS tests that read 8-bit integers from a + # storage buffer. + (('u2u8', ('extract_u16', a, 1)), ('u2u8', ('extract_u8', a, 2)), '!options->lower_extract_byte'), + (('u2u8', ('ushr', a, 8)), ('u2u8', ('extract_u8', a, 1)), '!options->lower_extract_byte'), + + # Common pattern after lowering 8-bit integers to 16-bit. + (('i2i16', ('u2u8', ('extract_u8', a, b))), ('i2i16', ('extract_i8', a, b))), + (('u2u16', ('u2u8', ('extract_u8', a, b))), ('u2u16', ('extract_u8', a, b))), + (('ubfe', a, 0, 8), ('extract_u8', a, 0), '!options->lower_extract_byte'), (('ubfe', a, 8, 8), ('extract_u8', a, 1), '!options->lower_extract_byte'), (('ubfe', a, 16, 8), ('extract_u8', a, 2), '!options->lower_extract_byte'),
