diff --git a/src/panfrost/midgard/midgard_compile.c b/src/panfrost/midgard/midgard_compile.c index c360a0879ed..0e5e9844591 100644 --- a/src/panfrost/midgard/midgard_compile.c +++ b/src/panfrost/midgard/midgard_compile.c @@ -657,6 +657,57 @@ mir_copy_src(midgard_instruction *ins, nir_alu_instr *instr, unsigned i, unsigne } } +/* Midgard features both fcsel and icsel, depending on whether you want int or + * float modifiers. NIR's csel is typeless, so we want a heuristic to guess if + * we should emit an int or float csel depending on what modifiers could be + * placed. In the absense of modifiers, this is probably arbitrary. */ + +static bool +mir_is_bcsel_float(nir_alu_instr *instr) +{ + nir_op intmods[] = { + nir_op_i2i8, nir_op_i2i16, + nir_op_i2i32, nir_op_i2i64 + }; + + nir_op floatmods[] = { + nir_op_fabs, nir_op_fneg, + nir_op_f2f16, nir_op_f2f32, + nir_op_f2f64 + }; + + nir_op floatdestmods[] = { + nir_op_fsat, nir_op_fsat_signed, nir_op_fclamp_pos, + nir_op_f2f16, nir_op_f2f32 + }; + + signed score = 0; + + for (unsigned i = 1; i < 3; ++i) { + nir_alu_src s = instr->src[i]; + for (unsigned q = 0; q < ARRAY_SIZE(intmods); ++q) { + if (pan_has_source_mod(&s, intmods[q])) + score--; + } + } + + for (unsigned i = 1; i < 3; ++i) { + nir_alu_src s = instr->src[i]; + for (unsigned q = 0; q < ARRAY_SIZE(floatmods); ++q) { + if (pan_has_source_mod(&s, floatmods[q])) + score++; + } + } + + for (unsigned q = 0; q < ARRAY_SIZE(floatdestmods); ++q) { + nir_dest *dest = &instr->dest.dest; + if (pan_has_dest_mod(&dest, floatdestmods[q])) + score++; + } + + return (score > 0); +} + static void emit_alu(compiler_context *ctx, nir_alu_instr *instr) { @@ -878,17 +929,11 @@ emit_alu(compiler_context *ctx, nir_alu_instr *instr) } case nir_op_b32csel: { - /* Midgard features both fcsel and icsel, depending on - * the type of the arguments/output. However, as long - * as we're careful we can _always_ use icsel and - * _never_ need fcsel, since the latter does additional - * floating-point-specific processing whereas the - * former just moves bits on the wire. It's not obvious - * why these are separate opcodes, save for the ability - * to do things like sat/pos/abs/neg for free */ - bool mixed = nir_is_non_scalar_swizzle(&instr->src[0], nr_components); - op = mixed ? midgard_alu_op_icsel_v : midgard_alu_op_icsel; + bool is_float = mir_is_bcsel_float(instr); + op = is_float ? + (mixed ? midgard_alu_op_fcsel_v : midgard_alu_op_fcsel) : + (mixed ? midgard_alu_op_icsel_v : midgard_alu_op_icsel); break; }