2 * Copyright © 2018 Intel Corporation
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
24 #include "nir_builder.h"
27 * Some ALU operations may not be supported in hardware in specific bit-sizes.
28 * This pass allows implementations to selectively lower such operations to
29 * a bit-size that is supported natively and then converts the result back to
30 * the original bit-size.
33 convert_to_bit_size(nir_builder
*bld
,
38 nir_alu_type base_type
= nir_alu_type_get_base_type(type
);
39 nir_alu_type lowered_type
= bit_size
| base_type
;
42 nir_type_conversion_op(type
, lowered_type
, nir_rounding_mode_undef
);
44 return nir_build_alu(bld
, opcode
, src
, NULL
, NULL
, NULL
);
48 lower_instr(nir_builder
*bld
, nir_alu_instr
*alu
, unsigned bit_size
)
50 const nir_op op
= alu
->op
;
51 unsigned dst_bit_size
= alu
->dest
.dest
.ssa
.bit_size
;
53 bld
->cursor
= nir_before_instr(&alu
->instr
);
55 /* Convert each source to the requested bit-size */
56 nir_ssa_def
*srcs
[4] = { NULL
, NULL
, NULL
, NULL
};
57 for (unsigned i
= 0; i
< nir_op_infos
[op
].num_inputs
; i
++) {
58 nir_ssa_def
*src
= nir_ssa_for_alu_src(bld
, alu
, i
);
60 nir_alu_type type
= nir_op_infos
[op
].input_types
[i
];
61 if (nir_alu_type_get_type_size(type
) == 0)
62 src
= convert_to_bit_size(bld
, src
, type
, bit_size
);
64 if (i
== 1 && (op
== nir_op_ishl
|| op
== nir_op_ishr
|| op
== nir_op_ushr
)) {
65 assert(util_is_power_of_two_nonzero(dst_bit_size
));
66 src
= nir_iand(bld
, src
, nir_imm_int(bld
, dst_bit_size
- 1));
72 /* Emit the lowered ALU instruction */
73 nir_ssa_def
*lowered_dst
=
74 nir_build_alu(bld
, op
, srcs
[0], srcs
[1], srcs
[2], srcs
[3]);
76 /* Convert result back to the original bit-size */
77 nir_alu_type type
= nir_op_infos
[op
].output_type
;
78 nir_ssa_def
*dst
= convert_to_bit_size(bld
, lowered_dst
, type
, dst_bit_size
);
79 nir_ssa_def_rewrite_uses(&alu
->dest
.dest
.ssa
, nir_src_for_ssa(dst
));
83 lower_impl(nir_function_impl
*impl
,
84 nir_lower_bit_size_callback callback
,
88 nir_builder_init(&b
, impl
);
89 bool progress
= false;
91 nir_foreach_block(block
, impl
) {
92 nir_foreach_instr_safe(instr
, block
) {
93 if (instr
->type
!= nir_instr_type_alu
)
96 nir_alu_instr
*alu
= nir_instr_as_alu(instr
);
97 assert(alu
->dest
.dest
.is_ssa
);
99 unsigned lower_bit_size
= callback(alu
, callback_data
);
100 if (lower_bit_size
== 0)
103 assert(lower_bit_size
!= alu
->dest
.dest
.ssa
.bit_size
);
105 lower_instr(&b
, alu
, lower_bit_size
);
111 nir_metadata_preserve(impl
, nir_metadata_block_index
|
112 nir_metadata_dominance
);
119 nir_lower_bit_size(nir_shader
*shader
,
120 nir_lower_bit_size_callback callback
,
123 bool progress
= false;
125 nir_foreach_function(function
, shader
) {
127 progress
|= lower_impl(function
->impl
, callback
, callback_data
);