<div dir="ltr">Now I'm wondering even more about my previous question about just splitting it into two instructions in NIR. <div class="gmail_quote"><div dir="ltr">On Tue, Dec 4, 2018 at 1:18 AM Iago Toral Quiroga <<a href="mailto:itoral@igalia.com">itoral@igalia.com</a>> wrote: </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">From: Samuel Iglesias Gonsálvez <<a href="mailto:siglesias@igalia.com" target="_blank">siglesias@igalia.com</a>> It is not supported directly in the HW, we need to convert to a 32-bit type first as intermediate step. v2 (Iago): handle conversions from 64-bit integers as well Signed-off-by: Samuel Iglesias Gonsálvez <<a href="mailto:siglesias@igalia.com" target="_blank">siglesias@igalia.com</a>> --- src/intel/compiler/brw_fs_nir.cpp | 42 ++++++++++++++++++++++++++++--- 1 file changed, 39 insertions(+), 3 deletions(-) diff --git a/src/intel/compiler/brw_fs_nir.cpp b/src/intel/compiler/brw_fs_nir.cpp index 7294f49ddc0..9f3d3bf9762 100644 --- a/src/intel/compiler/brw_fs_nir.cpp +++ b/src/intel/compiler/brw_fs_nir.cpp @@ -784,6 +784,19 @@ fs_visitor::nir_emit_alu(const fs_builder &bld, nir_alu_instr *instr) */ case nir_op_f2f16: + /* BDW PRM, vol02, Command Reference Instructions, mov - MOVE: + * + * "There is no direct conversion from HF to DF or DF to HF. + * Use two instructions and F (Float) as an intermediate type. + */ + if (nir_src_bit_size(instr->src[0].src) == 64) { + fs_reg tmp = bld.vgrf(BRW_REGISTER_TYPE_F, 1); + inst = bld.MOV(tmp, op[0]); + inst->saturate = instr->dest.saturate; + inst = bld.MOV(result, tmp); + inst->saturate = instr->dest.saturate; </blockquote><div> </div><div>I don't think you need both saturates. Just the first one should be sufficient as it clamps to [0, 1] which is representable in 16-bit float. </div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> + break; + } inst = bld.MOV(result, op[0]); inst->saturate = instr->dest.saturate; break; @@ -864,7 +877,32 @@ fs_visitor::nir_emit_alu(const fs_builder &bld, nir_alu_instr *instr) inst->saturate = instr->dest.saturate; break; } - /* fallthrough */ + inst = bld.MOV(result, op[0]); + inst->saturate = instr->dest.saturate; + break; + + case nir_op_i2f16: + case nir_op_u2f16: + /* BDW PRM, vol02, Command Reference Instructions, mov - MOVE: + * + * "There is no direct conversion from HF to Q/UQ or Q/UQ to HF. + * Use two instructions and F (Float) or a word integer type or a + * DWord integer type as an intermediate type." + */ + if (nir_src_bit_size(instr->src[0].src) == 64) { + brw_reg_type reg_type = instr->op == nir_op_i2f16 ? + BRW_REGISTER_TYPE_D : BRW_REGISTER_TYPE_UD; + fs_reg tmp = bld.vgrf(reg_type, 1); + inst = bld.MOV(tmp, op[0]); + inst->saturate = instr->dest.saturate; + inst = bld.MOV(result, tmp); + inst->saturate = instr->dest.saturate; + break; + } + inst = bld.MOV(result, op[0]); + inst->saturate = instr->dest.saturate; + break; + case nir_op_f2f32: case nir_op_f2i32: case nir_op_f2u32: @@ -874,8 +912,6 @@ fs_visitor::nir_emit_alu(const fs_builder &bld, nir_alu_instr *instr) case nir_op_u2u32: case nir_op_i2i16: case nir_op_u2u16: - case nir_op_i2f16: - case nir_op_u2f16: case nir_op_i2i8: case nir_op_u2u8: inst = bld.MOV(result, op[0]); -- 2.17.1 _______________________________________________ mesa-dev mailing list <a href="mailto:mesa-dev@lists.freedesktop.org" target="_blank">mesa-dev@lists.freedesktop.org</a> <a href="https://lists.freedesktop.org/mailman/listinfo/mesa-dev" rel="noreferrer" target="_blank">https://lists.freedesktop.org/mailman/listinfo/mesa-dev</a> </blockquote></div></div>