KonstantinSeurer
/
mesa
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

i965: Implement the new imod and irem opcodes 

Reviewed-by: Matt Turner <mattst88@gmail.com>
This commit is contained in:
Jason Ekstrand 2016-03-25 11:17:53 -07:00
parent 745b3d295e
commit 765dd65349
2 changed files with 72 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

36
src/mesa/drivers/dri/i965/brw_fs_nir.cpp
View File

@ -853,9 +853,45 @@ fs_visitor::nir_emit_alu(const fs_builder &bld, nir_alu_instr *instr)
unreachable("Should have been lowered by borrow_to_arith().");
case nir_op_umod:
case nir_op_irem:
/* According to the sign table for INT DIV in the Ivy Bridge PRM, it
* appears that our hardware just does the right thing for signed
* remainder.
*/
bld.emit(SHADER_OPCODE_INT_REMAINDER, result, op[0], op[1]);
break;
case nir_op_imod: {
/* Get a regular C-style remainder. If a % b == 0, set the predicate. */
bld.emit(SHADER_OPCODE_INT_REMAINDER, result, op[0], op[1]);
/* Math instructions don't support conditional mod */
inst = bld.MOV(bld.null_reg_d(), result);
inst->conditional_mod = BRW_CONDITIONAL_NZ;
/* Now, we need to determine if signs of the sources are different.
* When we XOR the sources, the top bit is 0 if they are the same and 1
* if they are different. We can then use a conditional modifier to
* turn that into a predicate. This leads us to an XOR.l instruction.
*
* Technically, according to the PRM, you're not allowed to use .l on a
* XOR instruction. However, emperical experiments and Curro's reading
* of the simulator source both indicate that it's safe.
*/
fs_reg tmp = bld.vgrf(BRW_REGISTER_TYPE_D);
inst = bld.XOR(tmp, op[0], op[1]);
inst->predicate = BRW_PREDICATE_NORMAL;
inst->conditional_mod = BRW_CONDITIONAL_L;
/* If the result of the initial remainder operation is non-zero and the
* two sources have different signs, add in a copy of op[1] to get the
* final integer modulus value.
*/
inst = bld.ADD(result, result, op[1]);
inst->predicate = BRW_PREDICATE_NORMAL;
break;
}
case nir_op_flt:
case nir_op_ilt:
case nir_op_ult:

36
src/mesa/drivers/dri/i965/brw_vec4_nir.cpp
View File

@ -1116,9 +1116,45 @@ vec4_visitor::nir_emit_alu(nir_alu_instr *instr)
break;
case nir_op_umod:
case nir_op_irem:
/* According to the sign table for INT DIV in the Ivy Bridge PRM, it
* appears that our hardware just does the right thing for signed
* remainder.
*/
emit_math(SHADER_OPCODE_INT_REMAINDER, dst, op[0], op[1]);
break;
case nir_op_imod: {
/* Get a regular C-style remainder. If a % b == 0, set the predicate. */
inst = emit_math(SHADER_OPCODE_INT_REMAINDER, dst, op[0], op[1]);
/* Math instructions don't support conditional mod */
inst = emit(MOV(dst_null_d(), src_reg(dst)));
inst->conditional_mod = BRW_CONDITIONAL_NZ;
/* Now, we need to determine if signs of the sources are different.
* When we XOR the sources, the top bit is 0 if they are the same and 1
* if they are different. We can then use a conditional modifier to
* turn that into a predicate. This leads us to an XOR.l instruction.
*
* Technically, according to the PRM, you're not allowed to use .l on a
* XOR instruction. However, emperical experiments and Curro's reading
* of the simulator source both indicate that it's safe.
*/
src_reg tmp = src_reg(this, glsl_type::ivec4_type);
inst = emit(XOR(dst_reg(tmp), op[0], op[1]));
inst->predicate = BRW_PREDICATE_NORMAL;
inst->conditional_mod = BRW_CONDITIONAL_L;
/* If the result of the initial remainder operation is non-zero and the
* two sources have different signs, add in a copy of op[1] to get the
* final integer modulus value.
*/
inst = emit(ADD(dst, src_reg(dst), op[1]));
inst->predicate = BRW_PREDICATE_NORMAL;
break;
}
case nir_op_ldexp:
unreachable("not reached: should be handled by ldexp_to_arith()");