From 8f40d392b9f67235064b0fb4d894097e361f1d7c Mon Sep 17 00:00:00 2001 From: Iago Toral Quiroga Date: Tue, 22 May 2018 08:17:38 +0200 Subject: [PATCH] intel/compiler: set correct precision fields for 3-source float instructions Source0 and Destination extract the floating-point precision automatically from the SrcType and DstType instruction fields respectively when they are set to types :F or :HF. For Source1 and Source2 operands, we use the new 1-bit fields Src1Type and Src2Type, where 0 means normal precision and 1 means half-precision. Since we always use the type of the destination for all operands when we emit 3-source instructions, we only need set Src1Type and Src2Type to 1 when we are emitting a half-precision instruction. v2: - Set the bit separately for each source based on its type so we can do mixed floating-point mode in the future (Topi). v3: - Use regular citation style for the comment referencing the PRM (Matt). - Decided not to add asserts in the emission code to check that only mixed HF/F types are used since such checks would break negative tests for brw_eu_validate.c (Matt) Reviewed-by: Topi Pohjolainen Reviewed-by: Jason Ekstrand Reviewed-by: Matt Turner --- src/intel/compiler/brw_eu_emit.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/src/intel/compiler/brw_eu_emit.c b/src/intel/compiler/brw_eu_emit.c index 7bd3003..f5318e3 100644 --- a/src/intel/compiler/brw_eu_emit.c +++ b/src/intel/compiler/brw_eu_emit.c @@ -843,6 +843,22 @@ brw_alu3(struct brw_codegen *p, unsigned opcode, struct brw_reg dest, */ brw_inst_set_3src_a16_src_type(devinfo, inst, dest.type); brw_inst_set_3src_a16_dst_type(devinfo, inst, dest.type); + + /* From the Bspec, 3D Media GPGPU, Instruction fields, srcType: + * + * "Three source instructions can use operands with mixed-mode + * precision. When SrcType field is set to :f or :hf it defines + * precision for source 0 only, and fields Src1Type and Src2Type + * define precision for other source operands: + * + * 0b = :f. Single precision Float (32-bit). + * 1b = :hf. Half precision Float (16-bit)." + */ + if (src1.type == BRW_REGISTER_TYPE_HF) + brw_inst_set_3src_a16_src1_type(devinfo, inst, 1); + + if (src2.type == BRW_REGISTER_TYPE_HF) + brw_inst_set_3src_a16_src2_type(devinfo, inst, 1); } } -- 2.7.4