It's reasonably well-known that you can replace an unsigned integer division by a constant with a sequence of multiply (by constant), adds, and shifts. This little series implements such an optimization for NIR. This second version of the series is based on the integer division by constant code by rediculousfish. I've tried to keep authorship of the various bits as accurate as I can hence the rather eclectic collection of patches.
Ian Romanick (2): nir: Add a saturated unsigned integer add opcode i965/fs: Implement nir_op_uadd_sat Jason Ekstrand (7): util: Add a simple big math library util: Generalize fast integer division to be variable bit-width util: Add tests for fast integer division by constants nir: Allow [iu]mul_high on non-32-bit types nir/lower_int64: Add support for [iu]mul_high nir: Add a pass for lowering integer division by constants i965: Enable nir_opt_idiv_const for all bit sizes Marek Olšák (3): util: import public domain code for integer division by a constant util: Add fast division helpers util: Add power-of-two divisor support to compute_fast_udiv_info configure.ac | 1 + src/compiler/Makefile.sources | 1 + src/compiler/nir/meson.build | 1 + src/compiler/nir/nir.h | 3 + src/compiler/nir/nir_constant_expressions.py | 1 + src/compiler/nir/nir_lower_int64.c | 54 ++ src/compiler/nir/nir_opcodes.py | 45 +- src/compiler/nir/nir_opt_idiv_const.c | 215 ++++++++ src/intel/compiler/brw_fs_nir.cpp | 5 + src/intel/compiler/brw_nir.c | 4 +- src/util/Makefile.am | 4 +- src/util/Makefile.sources | 3 + src/util/bigmath.h | 112 +++++ src/util/fast_idiv_by_const.c | 243 +++++++++ src/util/fast_idiv_by_const.h | 178 +++++++ src/util/meson.build | 4 + src/util/tests/fast_idiv_by_const/Makefile.am | 43 ++ .../fast_idiv_by_const_test.cpp | 472 ++++++++++++++++++ src/util/tests/fast_idiv_by_const/meson.build | 30 ++ 19 files changed, 1413 insertions(+), 6 deletions(-) create mode 100644 src/compiler/nir/nir_opt_idiv_const.c create mode 100644 src/util/bigmath.h create mode 100644 src/util/fast_idiv_by_const.c create mode 100644 src/util/fast_idiv_by_const.h create mode 100644 src/util/tests/fast_idiv_by_const/Makefile.am create mode 100644 src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test.cpp create mode 100644 src/util/tests/fast_idiv_by_const/meson.build -- 2.19.0 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
