diff options
Diffstat (limited to 'src/compiler/nir')
| -rw-r--r-- | src/compiler/nir/nir_lower_phis_to_scalar.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/src/compiler/nir/nir_lower_phis_to_scalar.c b/src/compiler/nir/nir_lower_phis_to_scalar.c index 16001f73685..c58a67826ce 100644 --- a/src/compiler/nir/nir_lower_phis_to_scalar.c +++ b/src/compiler/nir/nir_lower_phis_to_scalar.c @@ -75,10 +75,15 @@ is_phi_src_scalarizable(nir_phi_src *src, return should_lower_phi(nir_instr_as_phi(src_instr), state); case nir_instr_type_load_const: - case nir_instr_type_ssa_undef: /* These are trivially scalarizable */ return true; + case nir_instr_type_ssa_undef: + /* The caller of this function is going to OR the results and we don't + * want undefs to count so we return false. + */ + return false; + case nir_instr_type_intrinsic: { nir_intrinsic_instr *src_intrin = nir_instr_as_intrinsic(src_instr); @@ -150,11 +155,16 @@ should_lower_phi(nir_phi_instr *phi, struct lower_phis_to_scalar_state *state) */ entry = _mesa_hash_table_insert(state->phi_table, phi, (void *)(intptr_t)1); - bool scalarizable = true; + bool scalarizable = false; nir_foreach_phi_src(src, phi) { + /* This loop ignores srcs that are not scalarizable because its likely + * still worth copying to temps if another phi source is scalarizable. + * This reduces register spilling by a huge amount in the i965 driver for + * Deus Ex: MD. + */ scalarizable = is_phi_src_scalarizable(src, state); - if (!scalarizable) + if (scalarizable) break; } |