This series implements a bunch of related optimizations that run at once as part of the same pass to eliminate control flow that is useless. This includes both unreachable code and useless loops, i.e. loops that don't compute a result used by the rest of the code. To do this, I needed to change some low-level things that change the behavior of nir_instr_remove() (see patch 2 for details), but I've tested the series on piglit and there are no regressions, and there are no shader-db changes either.
This is rebased on Jason's series to use lists for use-def sets; it turns out that the changes required were pretty minimal. The series is also available at: git://people.freedesktop.org/~cwabbott0/mesa nir-dead-cf-v3 Connor Abbott (9): nir/vars_to_ssa: don't rewrite removed instructions nir: insert ssa_undef instructions when cleanup up defs/uses nir: add an optimization for removing dead control flow nir/validate: validate successors at the end of a loop nir/dead_cf: delete code that's unreachable due to jumps nir: add nir_block_get_following_loop() helper nir: add a helper for iterating over blocks in a cf node nir/dead_cf: add support for removing useless loops i965/fs/nir: enable the dead control flow optimization src/glsl/Makefile.sources | 1 + src/glsl/nir/nir.c | 94 ++++++++-- src/glsl/nir/nir.h | 12 ++ src/glsl/nir/nir_lower_vars_to_ssa.c | 3 +- src/glsl/nir/nir_opt_dead_cf.c | 332 +++++++++++++++++++++++++++++++++++ src/glsl/nir/nir_validate.c | 21 +++ src/mesa/drivers/dri/i965/brw_nir.c | 2 + 7 files changed, 452 insertions(+), 13 deletions(-) create mode 100644 src/glsl/nir/nir_opt_dead_cf.c -- 2.1.0 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
