<div dir="ltr">Reviewed-by: Jason Ekstrand <<a href="mailto:jason.ekstrand@intel.com">jason.ekstrand@intel.com</a>></div><div class="gmail_extra"> <div class="gmail_quote">On Thu, Jan 22, 2015 at 3:41 AM, Kenneth Graunke <<a href="mailto:kenneth@whitecape.org" target="_blank">kenneth@whitecape.org</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Matt and I noticed that one of the shaders hurt by INTEL_USE_NIR=1 had load_input and load_uniform intrinsics repeated several times, with the same parameters, but each one generating a distinct SSA value. This made ALU operations on those values appear distinct as well. Generating distinct SSA values is silly - these are read only variables. CSE'ing them makes everything use a single SSA value, which then allows other operations to be CSE'd away as well. Generalizing a bit, it seems like we should be able to safely CSE any intrinsics that can be eliminated and reordered. I didn't implement support for variables for the time being. v2: Assert that info->num_variables == 0 (requested by Jason). total NIR instructions in shared programs: 2435936 -> 2023511 (-16.93%) NIR instructions in affected programs: 2413496 -> 2001071 (-17.09%) helped: 16872 total i965 instructions in shared programs: 6028987 -> 6008427 (-0.34%) i965 instructions in affected programs: 640654 -> 620094 (-3.21%) helped: 2071 HURT: 585 GAINED: 14 LOST: 25 Signed-off-by: Kenneth Graunke <<a href="mailto:kenneth@whitecape.org">kenneth@whitecape.org</a>> --- src/glsl/nir/nir_opt_cse.c | 40 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 38 insertions(+), 2 deletions(-) Here's v2 of CSE for intrinsics. Sounds like it's good to go. diff --git a/src/glsl/nir/nir_opt_cse.c b/src/glsl/nir/nir_opt_cse.c index fef1678..b3e9c0d 100644 --- a/src/glsl/nir/nir_opt_cse.c +++ b/src/glsl/nir/nir_opt_cse.c @@ -112,7 +112,34 @@ nir_instrs_equal(nir_instr *instr1, nir_instr *instr2) return true; } - case nir_instr_type_intrinsic: + case nir_instr_type_intrinsic: { + nir_intrinsic_instr *intrinsic1 = nir_instr_as_intrinsic(instr1); + nir_intrinsic_instr *intrinsic2 = nir_instr_as_intrinsic(instr2); + const nir_intrinsic_info *info = + &nir_intrinsic_infos[intrinsic1->intrinsic]; + + if (intrinsic1->intrinsic != intrinsic2->intrinsic || + intrinsic1->num_components != intrinsic2->num_components) + return false; + + if (info->has_dest && intrinsic1->dest.ssa.num_components != + intrinsic2->dest.ssa.num_components) + return false; + + for (unsigned i = 0; i < info->num_srcs; i++) { + if (!nir_srcs_equal(intrinsic1->src[i], intrinsic2->src[i])) + return false; + } + + assert(info->num_variables == 0); + + for (unsigned i = 0; i < info->num_indices; i++) { + if (intrinsic1->const_index[i] != intrinsic2->const_index[i]) + return false; + } + + return true; + } case nir_instr_type_call: case nir_instr_type_jump: case nir_instr_type_ssa_undef: @@ -151,7 +178,13 @@ nir_instr_can_cse(nir_instr *instr) return true; case nir_instr_type_tex: return false; /* TODO */ - case nir_instr_type_intrinsic: + case nir_instr_type_intrinsic: { + const nir_intrinsic_info *info = + &nir_intrinsic_infos[nir_instr_as_intrinsic(instr)->intrinsic]; + return (info->flags & NIR_INTRINSIC_CAN_ELIMINATE) && + (info->flags & NIR_INTRINSIC_CAN_REORDER) && + info->num_variables == 0; /* not implemented yet */ + } case nir_instr_type_call: case nir_instr_type_jump: case nir_instr_type_ssa_undef: @@ -176,6 +209,9 @@ nir_instr_get_dest_ssa_def(nir_instr *instr) case nir_instr_type_phi: assert(nir_instr_as_phi(instr)->dest.is_ssa); return &nir_instr_as_phi(instr)->dest.ssa; + case nir_instr_type_intrinsic: + assert(nir_instr_as_intrinsic(instr)->dest.is_ssa); + return &nir_instr_as_intrinsic(instr)->dest.ssa; default: unreachable("We never ask for any of these"); } -- 2.2.2 _______________________________________________ mesa-dev mailing list <a href="mailto:mesa-dev@lists.freedesktop.org">mesa-dev@lists.freedesktop.org</a> <a href="http://lists.freedesktop.org/mailman/listinfo/mesa-dev" target="_blank">http://lists.freedesktop.org/mailman/listinfo/mesa-dev</a> </blockquote></div> </div>