/* -*- mode: C; c-file-style: "k&r"; tab-width 4; indent-tabs-mode: t; -*- */
/*
* Copyright (C) 2014 Rob Clark <robclark@freedesktop.org>
*
* 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.
*
* Authors:
* Rob Clark <robclark@freedesktop.org>
*/
#include "pipe/p_shader_tokens.h"
#include "util/u_math.h"
#include "freedreno_util.h"
#include "ir3.h"
/*
* Legalize:
*
* We currently require that scheduling ensures that we have enough nop's
* in all the right places. The legalize step mostly handles fixing up
* instruction flags ((ss)/(sy)/(ei)), and collapses sequences of nop's
* into fewer nop's w/ rpt flag.
*/
struct ir3_legalize_ctx {
struct ir3_block *block;
bool has_samp;
int max_bary;
};
static void legalize(struct ir3_legalize_ctx *ctx)
{
struct ir3_block *block = ctx->block;
struct ir3_instruction *n;
struct ir3 *shader = block->shader;
struct ir3_instruction *end =
ir3_instr_create(block, 0, OPC_END);
struct ir3_instruction *last_input = NULL;
struct ir3_instruction *last_rel = NULL;
regmask_t needs_ss_war; /* write after read */
regmask_t needs_ss;
regmask_t needs_sy;
regmask_init(&needs_ss_war);
regmask_init(&needs_ss);
regmask_init(&needs_sy);
shader->instrs_count = 0;
for (n = block->head; n; n = n->next) {
struct ir3_register *reg;
unsigned i;
if (is_meta(n))
continue;
if (is_input(n)) {
struct ir3_register *inloc = n->regs[1];
assert(inloc
->flags
& IR3_REG_IMMED
);
ctx->max_bary = MAX2(ctx->max_bary, inloc->iim_val);
}
/* NOTE: consider dst register too.. it could happen that
* texture sample instruction (for example) writes some
* components which are unused. A subsequent instruction
* that writes the same register can race w/ the sam instr
* resulting in undefined results:
*/
for (i = 0; i < n->regs_count; i++) {
reg = n->regs[i];
if (reg_gpr(reg)) {
/* TODO: we probably only need (ss) for alu
* instr consuming sfu result.. need to make
* some tests for both this and (sy)..
*/
if (regmask_get(&needs_ss, reg)) {
n->flags |= IR3_INSTR_SS;
regmask_init(&needs_ss);
}
if (regmask_get(&needs_sy, reg)) {
n->flags |= IR3_INSTR_SY;
regmask_init(&needs_sy);
}
}
/* TODO: is it valid to have address reg loaded from a
* relative src (ie. mova a0, c<a0.x+4>)? If so, the
* last_rel check below should be moved ahead of this:
*/
if (reg->flags & IR3_REG_RELATIV)
last_rel = n;
}
if (n->regs_count > 0) {
reg = n->regs[0];
if (regmask_get(&needs_ss_war, reg)) {
n->flags |= IR3_INSTR_SS;
regmask_init(&needs_ss_war); // ??? I assume?
}
if (last_rel && (reg->num == regid(REG_A0, 0))) {
last_rel->flags |= IR3_INSTR_UL;
last_rel = NULL;
}
}
/* cat5+ does not have an (ss) bit, if needed we need to
* insert a nop to carry the sync flag. Would be kinda
* clever if we were aware of this during scheduling, but
* this should be a pretty rare case:
*/
if ((n->flags & IR3_INSTR_SS) && (n->category >= 5)) {
struct ir3_instruction *nop;
nop = ir3_instr_create(block, 0, OPC_NOP);
nop->flags |= IR3_INSTR_SS;
n->flags &= ~IR3_INSTR_SS;
}
/* need to be able to set (ss) on first instruction: */
if ((shader->instrs_count == 0) && (n->category >= 5))
ir3_instr_create(block, 0, OPC_NOP);
if (is_nop(n) && shader->instrs_count) {
struct ir3_instruction *last =
shader->instrs[shader->instrs_count-1];
if (is_nop(last) && (last->repeat < 5)) {
last->repeat++;
last->flags |= n->flags;
continue;
}
}
shader->instrs[shader->instrs_count++] = n;
if (is_sfu(n))
regmask_set(&needs_ss, n->regs[0]);
if (is_tex(n)) {
/* this ends up being the # of samp instructions.. but that
* is ok, everything else only cares whether it is zero or
* not. We do this here, rather than when we encounter a
* SAMP decl, because (especially in binning pass shader)
* the samp instruction(s) could get eliminated if the
* result is not used.
*/
ctx->has_samp = true;
regmask_set(&needs_sy, n->regs[0]);
} else if (is_mem(n)) {
regmask_set(&needs_sy, n->regs[0]);
}
/* both tex/sfu appear to not always immediately consume
* their src register(s):
*/
if (is_tex(n) || is_sfu(n) || is_mem(n)) {
foreach_src(reg, n) {
if (reg_gpr(reg))
regmask_set(&needs_ss_war, reg);
}
}
if (is_input(n))
last_input = n;
}
if (last_input) {
/* special hack.. if using ldlv to bypass interpolation,
* we need to insert a dummy bary.f on which we can set
* the (ei) flag:
*/
if (is_mem(last_input) && (last_input->opc == OPC_LDLV)) {
int i, cnt;
/* note that ir3_instr_create() inserts into
* shader->instrs[] and increments the count..
* so we need to bump up the cnt initially (to
* avoid it clobbering the last real instr) and
* restore it after.
*/
cnt = ++shader->instrs_count;
/* inserting instructions would be a bit nicer if list.. */
for (i = cnt - 2; i >= 0; i--) {
if (shader->instrs[i] == last_input) {
/* (ss)bary.f (ei)r63.x, 0, r0.x */
last_input = ir3_instr_create(block, 2, OPC_BARY_F);
last_input->flags |= IR3_INSTR_SS;
ir3_reg_create(last_input, regid(63, 0), 0);
ir3_reg_create(last_input, 0, IR3_REG_IMMED)->iim_val = 0;
ir3_reg_create(last_input, regid(0, 0), 0);
shader->instrs[i + 1] = last_input;
break;
}
shader->instrs[i + 1] = shader->instrs[i];
}
shader->instrs_count = cnt;
}
last_input->regs[0]->flags |= IR3_REG_EI;
}
if (last_rel)
last_rel->flags |= IR3_INSTR_UL;
shader->instrs[shader->instrs_count++] = end;
shader->instrs[0]->flags |= IR3_INSTR_SS | IR3_INSTR_SY;
}
void ir3_block_legalize(struct ir3_block *block,
bool *has_samp, int *max_bary)
{
struct ir3_legalize_ctx ctx = {
.block = block,
.max_bary = -1,
};
legalize(&ctx);
*has_samp = ctx.has_samp;
*max_bary = ctx.max_bary;
}