From 9a3cb6f5fec040dea4a229b93f789995b36f9c09 Mon Sep 17 00:00:00 2001 From: Jason Ekstrand Date: Mon, 24 Jun 2019 16:21:07 -0500 Subject: [PATCH] nir/loop_analyze: Bail if we encounter swizzles None of the current code knows what to do with swizzles. Take the safe option for now and bail if we see one. This does have a small shader-db impact but it is at least safe. Shader-db results on Kaby Lake: total loops in shared programs: 4364 -> 4388 (0.55%) loops in affected programs: 5 -> 29 (480.00%) helped: 5 HURT: 29 Shader-db results on Haswell: total loops in shared programs: 4373 -> 4370 (-0.07%) loops in affected programs: 5 -> 2 (-60.00%) helped: 5 HURT: 2 Fixes: 6772a17acc8ee "nir: Add a loop analysis pass" Reviewed-by: Timothy Arceri --- src/compiler/nir/nir_loop_analyze.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/src/compiler/nir/nir_loop_analyze.c b/src/compiler/nir/nir_loop_analyze.c index 480ed791cfe..979413c2cb0 100644 --- a/src/compiler/nir/nir_loop_analyze.c +++ b/src/compiler/nir/nir_loop_analyze.c @@ -320,6 +320,12 @@ compute_induction_information(loop_info_state *state) if (!is_var_phi(var)) continue; + /* We only handle scalars because none of the rest of the loop analysis + * code can properly handle swizzles. + */ + if (var->def->num_components > 1) + continue; + nir_phi_instr *phi = nir_instr_as_phi(var->def->parent_instr); nir_basic_induction_var *biv = rzalloc(state, nir_basic_induction_var); @@ -358,7 +364,9 @@ compute_induction_information(loop_info_state *state) for (unsigned i = 0; i < 2; i++) { /* Is one of the operands const, and the other the phi */ if (alu->src[i].src.ssa->parent_instr->type == nir_instr_type_load_const && + alu->src[i].swizzle[0] == 0 && alu->src[1-i].src.ssa == &phi->dest.ssa) + assert(alu->src[1-i].swizzle[0] == 0); biv->invariant = get_loop_var(alu->src[i].src.ssa, state); } } @@ -557,6 +565,10 @@ try_find_limit_of_alu(nir_loop_variable *limit, nir_const_value *limit_val, if (limit_alu->op == nir_op_imin || limit_alu->op == nir_op_fmin) { + /* We don't handle swizzles here */ + if (limit_alu->src[0].swizzle[0] > 0 || limit_alu->src[1].swizzle[0] > 0) + return false; + limit = get_loop_var(limit_alu->src[0].src.ssa, state); if (!is_var_constant(limit)) @@ -828,10 +840,16 @@ try_find_trip_count_vars_in_iand(nir_alu_instr **alu, assert((*alu)->op == nir_op_ieq || (*alu)->op == nir_op_inot); nir_ssa_def *iand_def = (*alu)->src[0].src.ssa; + /* This is used directly in an if condition so it must be a scalar */ + assert(iand_def->num_components == 1); if ((*alu)->op == nir_op_ieq) { nir_ssa_def *zero_def = (*alu)->src[1].src.ssa; + /* We don't handle swizzles here */ + if ((*alu)->src[0].swizzle[0] > 0 || (*alu)->src[1].swizzle[0] > 0) + return; + if (iand_def->parent_instr->type != nir_instr_type_alu || zero_def->parent_instr->type != nir_instr_type_load_const) { @@ -858,6 +876,10 @@ try_find_trip_count_vars_in_iand(nir_alu_instr **alu, if (iand->op != nir_op_iand) return; + /* We don't handle swizzles here */ + if ((*alu)->src[0].swizzle[0] > 0 || (*alu)->src[1].swizzle[0] > 0) + return; + /* Check if iand src is a terminator condition and try get induction var * and trip limit var. */ -- 2.30.2