mesa/src/broadcom/compiler/v3d_nir_lower_load_store_bi...

269 lines
9.8 KiB
C

/*
* Copyright © 2021 Raspberry Pi Ltd
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#include "compiler/v3d_compiler.h"
#include "compiler/nir/nir_builder.h"
/**
* The V3D TMU unit can only do 32-bit general vector access so for anything
* else we need to split vector load/store instructions to scalar.
*
* Note that a vectorization pass after this lowering may be able to
* re-vectorize some of these using 32-bit load/store instructions instead,
* which we do support.
*/
static int
value_src(nir_intrinsic_op intrinsic)
{
switch (intrinsic) {
case nir_intrinsic_store_ssbo:
case nir_intrinsic_store_scratch:
case nir_intrinsic_store_global_2x32:
return 0;
default:
unreachable("Unsupported intrinsic");
}
}
static int
offset_src(nir_intrinsic_op intrinsic)
{
switch (intrinsic) {
case nir_intrinsic_load_uniform:
case nir_intrinsic_load_shared:
case nir_intrinsic_load_scratch:
case nir_intrinsic_load_global_2x32:
return 0;
case nir_intrinsic_load_ubo:
case nir_intrinsic_load_ssbo:
case nir_intrinsic_store_scratch:
case nir_intrinsic_store_global_2x32:
return 1;
case nir_intrinsic_store_ssbo:
return 2;
default:
unreachable("Unsupported intrinsic");
}
}
static nir_intrinsic_instr *
init_scalar_intrinsic(nir_builder *b,
nir_intrinsic_instr *intr,
uint32_t component,
nir_ssa_def *offset,
uint32_t bit_size,
nir_ssa_def **scalar_offset)
{
nir_intrinsic_instr *new_intr =
nir_intrinsic_instr_create(b->shader, intr->intrinsic);
nir_intrinsic_copy_const_indices(new_intr, intr);
const int offset_units = bit_size / 8;
assert(offset_units >= 1);
if (nir_intrinsic_has_align_mul(intr)) {
assert(nir_intrinsic_has_align_offset(intr));
unsigned align_mul = nir_intrinsic_align_mul(intr);
unsigned align_off = nir_intrinsic_align_offset(intr);
align_off += offset_units * component;
align_off = align_off % align_mul;
nir_intrinsic_set_align(new_intr, align_mul, align_off);
}
*scalar_offset = offset;
unsigned offset_adj = offset_units * component;
if (nir_intrinsic_has_base(intr)) {
nir_intrinsic_set_base(
new_intr, nir_intrinsic_base(intr) + offset_adj);
} else {
*scalar_offset =
nir_iadd(b, offset,
nir_imm_intN_t(b, offset_adj,
offset->bit_size));
}
new_intr->num_components = 1;
return new_intr;
}
static bool
lower_load_bitsize(struct v3d_compile *c,
nir_builder *b,
nir_intrinsic_instr *intr)
{
uint32_t bit_size = nir_dest_bit_size(intr->dest);
if (bit_size == 32)
return false;
/* No need to split if it is already scalar */
int num_comp = nir_intrinsic_dest_components(intr);
if (num_comp <= 1)
return false;
b->cursor = nir_before_instr(&intr->instr);
/* For global 2x32 we ignore Y component because it must be zero */
unsigned offset_idx = offset_src(intr->intrinsic);
nir_ssa_def *offset = nir_ssa_for_src(b, intr->src[offset_idx], 1);
/* Split vector store to multiple scalar loads */
nir_ssa_def *dest_components[4] = { NULL };
const nir_intrinsic_info *info = &nir_intrinsic_infos[intr->intrinsic];
for (int component = 0; component < num_comp; component++) {
nir_ssa_def *scalar_offset;
nir_intrinsic_instr *new_intr =
init_scalar_intrinsic(b, intr, component, offset,
bit_size, &scalar_offset);
for (unsigned i = 0; i < info->num_srcs; i++) {
if (i == offset_idx) {
nir_ssa_def *final_offset;
final_offset = intr->intrinsic != nir_intrinsic_load_global_2x32 ?
scalar_offset :
nir_vec2(b, scalar_offset,
nir_imm_int(b, 0));
new_intr->src[i] = nir_src_for_ssa(final_offset);
} else {
new_intr->src[i] = intr->src[i];
}
}
nir_ssa_dest_init(&new_intr->instr, &new_intr->dest,
1, bit_size, NULL);
dest_components[component] = &new_intr->dest.ssa;
nir_builder_instr_insert(b, &new_intr->instr);
}
nir_ssa_def *new_dst = nir_vec(b, dest_components, num_comp);
nir_ssa_def_rewrite_uses(&intr->dest.ssa, new_dst);
nir_instr_remove(&intr->instr);
return true;
}
static bool
lower_store_bitsize(struct v3d_compile *c,
nir_builder *b,
nir_intrinsic_instr *intr)
{
/* No need to split if it is already scalar */
int value_idx = value_src(intr->intrinsic);
int num_comp = nir_intrinsic_src_components(intr, value_idx);
if (num_comp <= 1)
return false;
/* No need to split if it is 32-bit */
if (nir_src_bit_size(intr->src[value_idx]) == 32)
return false;
nir_ssa_def *value = nir_ssa_for_src(b, intr->src[value_idx], num_comp);
b->cursor = nir_before_instr(&intr->instr);
/* For global 2x32 we ignore Y component because it must be zero */
unsigned offset_idx = offset_src(intr->intrinsic);
nir_ssa_def *offset = nir_ssa_for_src(b, intr->src[offset_idx], 1);
/* Split vector store to multiple scalar stores */
const nir_intrinsic_info *info = &nir_intrinsic_infos[intr->intrinsic];
unsigned wrmask = nir_intrinsic_write_mask(intr);
while (wrmask) {
unsigned component = ffs(wrmask) - 1;
nir_ssa_def *scalar_offset;
nir_intrinsic_instr *new_intr =
init_scalar_intrinsic(b, intr, component, offset,
value->bit_size, &scalar_offset);
nir_intrinsic_set_write_mask(new_intr, 0x1);
for (unsigned i = 0; i < info->num_srcs; i++) {
if (i == value_idx) {
nir_ssa_def *scalar_value =
nir_channels(b, value, 1 << component);
new_intr->src[i] = nir_src_for_ssa(scalar_value);
} else if (i == offset_idx) {
nir_ssa_def *final_offset;
final_offset = intr->intrinsic != nir_intrinsic_store_global_2x32 ?
scalar_offset :
nir_vec2(b, scalar_offset,
nir_imm_int(b, 0));
new_intr->src[i] = nir_src_for_ssa(final_offset);
} else {
new_intr->src[i] = intr->src[i];
}
}
nir_builder_instr_insert(b, &new_intr->instr);
wrmask &= ~(1 << component);
}
nir_instr_remove(&intr->instr);
return true;
}
static bool
lower_load_store_bitsize(nir_builder *b, nir_instr *instr, void *data)
{
struct v3d_compile *c = (struct v3d_compile *) data;
if (instr->type != nir_instr_type_intrinsic)
return false;
nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
switch (intr->intrinsic) {
case nir_intrinsic_load_ssbo:
case nir_intrinsic_load_ubo:
case nir_intrinsic_load_uniform:
case nir_intrinsic_load_scratch:
case nir_intrinsic_load_global_2x32:
return lower_load_bitsize(c, b, intr);
case nir_intrinsic_store_ssbo:
case nir_intrinsic_store_scratch:
case nir_intrinsic_store_global_2x32:
return lower_store_bitsize(c, b, intr);
default:
return false;
}
}
bool
v3d_nir_lower_load_store_bitsize(nir_shader *s, struct v3d_compile *c)
{
return nir_shader_instructions_pass(s,
lower_load_store_bitsize,
nir_metadata_block_index |
nir_metadata_dominance,
c);
}