From 83fdefc06287f6c8bbb3bb5bb4ccd36d653017a3 Mon Sep 17 00:00:00 2001 From: Jason Ekstrand Date: Tue, 12 Mar 2019 16:25:39 -0500 Subject: [PATCH] nir/loop_unroll: Fix out-of-bounds access handling The previous code was completely broken when it came to constructing the undef values. I'm not sure how it ever worked. For the case of a copy that reads an undefined value, we can just delete the copy because the destination is a valid undefined value. This saves us the effort of trying to construct a value for an arbitrary copy_deref intrinsic. Fixes: e8a8937a04 "nir: add partial loop unrolling support" Reviewed-by: Timothy Arceri --- src/compiler/nir/nir_opt_loop_unroll.c | 14 ++------------ 1 file changed, 2 insertions(+), 12 deletions(-) diff --git a/src/compiler/nir/nir_opt_loop_unroll.c b/src/compiler/nir/nir_opt_loop_unroll.c index 06ec78b8068..b2696d4aadb 100644 --- a/src/compiler/nir/nir_opt_loop_unroll.c +++ b/src/compiler/nir/nir_opt_loop_unroll.c @@ -670,11 +670,9 @@ remove_out_of_bounds_induction_use(nir_shader *shader, nir_loop *loop, if (is_access_out_of_bounds(term, nir_src_as_deref(intrin->src[0]), trip_count)) { if (intrin->intrinsic == nir_intrinsic_load_deref) { - assert(intrin->src[0].is_ssa); - nir_ssa_def *a_ssa = intrin->src[0].ssa; nir_ssa_def *undef = - nir_ssa_undef(&b, intrin->num_components, - a_ssa->bit_size); + nir_ssa_undef(&b, intrin->dest.ssa.num_components, + intrin->dest.ssa.bit_size); nir_ssa_def_rewrite_uses(&intrin->dest.ssa, nir_src_for_ssa(undef)); } else { @@ -686,14 +684,6 @@ remove_out_of_bounds_induction_use(nir_shader *shader, nir_loop *loop, if (intrin->intrinsic == nir_intrinsic_copy_deref && is_access_out_of_bounds(term, nir_src_as_deref(intrin->src[1]), trip_count)) { - assert(intrin->src[1].is_ssa); - nir_ssa_def *a_ssa = intrin->src[1].ssa; - nir_ssa_def *undef = - nir_ssa_undef(&b, intrin->num_components, a_ssa->bit_size); - - /* Replace the copy with a store of the undefined value */ - b.cursor = nir_before_instr(instr); - nir_store_deref(&b, nir_src_as_deref(intrin->src[0]), undef, ~0); nir_instr_remove(instr); } } -- 2.30.2