/*
* Copyright © 2010 Intel Corporation
*
* 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.
*/
/** @file brw_fs.cpp
*
* This file drives the GLSL IR -> LIR translation, contains the
* optimizations on the LIR, and drives the generation of native code
* from the LIR.
*/
extern "C" {
#include <sys/types.h>
#include "main/hash_table.h"
#include "main/macros.h"
#include "main/shaderobj.h"
#include "main/uniforms.h"
#include "main/fbobject.h"
#include "program/prog_parameter.h"
#include "program/prog_print.h"
#include "program/register_allocate.h"
#include "program/sampler.h"
#include "program/hash_table.h"
#include "brw_context.h"
#include "brw_eu.h"
#include "brw_wm.h"
}
#include "brw_fs.h"
#include "glsl/glsl_types.h"
void
fs_inst::init()
{
memset(this, 0, sizeof(*this));
this->opcode = BRW_OPCODE_NOP;
this->conditional_mod = BRW_CONDITIONAL_NONE;
this->dst = reg_undef;
this->src[0] = reg_undef;
this->src[1] = reg_undef;
this->src[2] = reg_undef;
/* This will be the case for almost all instructions. */
this->regs_written = 1;
}
fs_inst::fs_inst()
{
init();
}
fs_inst::fs_inst(enum opcode opcode)
{
init();
this->opcode = opcode;
}
fs_inst::fs_inst(enum opcode opcode, fs_reg dst)
{
init();
this->opcode = opcode;
this->dst = dst;
if (dst.file == GRF)
assert(dst.reg_offset >= 0);
}
fs_inst::fs_inst(enum opcode opcode, fs_reg dst, fs_reg src0)
{
init();
this->opcode = opcode;
this->dst = dst;
this->src[0] = src0;
if (dst.file == GRF)
assert(dst.reg_offset >= 0);
if (src[0].file == GRF)
assert(src[0].reg_offset >= 0);
}
fs_inst::fs_inst(enum opcode opcode, fs_reg dst, fs_reg src0, fs_reg src1)
{
init();
this->opcode = opcode;
this->dst = dst;
this->src[0] = src0;
this->src[1] = src1;
if (dst.file == GRF)
assert(dst.reg_offset >= 0);
if (src[0].file == GRF)
assert(src[0].reg_offset >= 0);
if (src[1].file == GRF)
assert(src[1].reg_offset >= 0);
}
fs_inst::fs_inst(enum opcode opcode, fs_reg dst,
fs_reg src0, fs_reg src1, fs_reg src2)
{
init();
this->opcode = opcode;
this->dst = dst;
this->src[0] = src0;
this->src[1] = src1;
this->src[2] = src2;
if (dst.file == GRF)
assert(dst.reg_offset >= 0);
if (src[0].file == GRF)
assert(src[0].reg_offset >= 0);
if (src[1].file == GRF)
assert(src[1].reg_offset >= 0);
if (src[2].file == GRF)
assert(src[2].reg_offset >= 0);
}
#define ALU1(op) \
fs_inst * \
fs_visitor::op(fs_reg dst, fs_reg src0) \
{ \
return new(mem_ctx) fs_inst(BRW_OPCODE_##op, dst, src0); \
}
#define ALU2(op) \
fs_inst * \
fs_visitor::op(fs_reg dst, fs_reg src0, fs_reg src1) \
{ \
return new(mem_ctx) fs_inst(BRW_OPCODE_##op, dst, src0, src1); \
}
#define ALU3(op) \
fs_inst * \
fs_visitor::op(fs_reg dst, fs_reg src0, fs_reg src1, fs_reg src2) \
{ \
return new(mem_ctx) fs_inst(BRW_OPCODE_##op, dst, src0, src1, src2);\
}
ALU1(NOT)
ALU1(MOV)
ALU1(FRC)
ALU1(RNDD)
ALU1(RNDE)
ALU1(RNDZ)
ALU2(ADD)
ALU2(MUL)
ALU2(MACH)
ALU2(AND)
ALU2(OR)
ALU2(XOR)
ALU2(SHL)
ALU2(SHR)
ALU2(ASR)
ALU3(LRP)
ALU1(BFREV)
ALU3(BFE)
ALU2(BFI1)
ALU3(BFI2)
ALU1(FBH)
ALU1(FBL)
ALU1(CBIT)
/** Gen4 predicated IF. */
fs_inst *
fs_visitor::IF(uint32_t predicate)
{
fs_inst *inst = new(mem_ctx) fs_inst(BRW_OPCODE_IF);
inst->predicate = predicate;
return inst;
}
/** Gen6+ IF with embedded comparison. */
fs_inst *
fs_visitor::IF(fs_reg src0, fs_reg src1, uint32_t condition)
{
assert(brw->gen >= 6);
fs_inst *inst = new(mem_ctx) fs_inst(BRW_OPCODE_IF,
reg_null_d, src0, src1);
inst->conditional_mod = condition;
return inst;
}
/**
* CMP: Sets the low bit of the destination channels with the result
* of the comparison, while the upper bits are undefined, and updates
* the flag register with the packed 16 bits of the result.
*/
fs_inst *
fs_visitor::CMP(fs_reg dst, fs_reg src0, fs_reg src1, uint32_t condition)
{
fs_inst *inst;
/* Take the instruction:
*
* CMP null<d> src0<f> src1<f>
*
* Original gen4 does type conversion to the destination type before
* comparison, producing garbage results for floating point comparisons.
* gen5 does the comparison on the execution type (resolved source types),
* so dst type doesn't matter. gen6 does comparison and then uses the
* result as if it was the dst type with no conversion, which happens to
* mostly work out for float-interpreted-as-int since our comparisons are
* for >0, =0, <0.
*/
if (brw->gen == 4) {
dst.type = src0.type;
if (dst.file == HW_REG)
dst.fixed_hw_reg.type = dst.type;
}
resolve_ud_negate(&src0);
resolve_ud_negate(&src1);
inst = new(mem_ctx) fs_inst(BRW_OPCODE_CMP, dst, src0, src1);
inst->conditional_mod = condition;
return inst;
}
exec_list
fs_visitor::VARYING_PULL_CONSTANT_LOAD(fs_reg dst, fs_reg surf_index,
fs_reg varying_offset,
uint32_t const_offset)
{
exec_list instructions;
fs_inst *inst;
/* We have our constant surface use a pitch of 4 bytes, so our index can
* be any component of a vector, and then we load 4 contiguous
* components starting from that.
*
* We break down the const_offset to a portion added to the variable
* offset and a portion done using reg_offset, which means that if you
* have GLSL using something like "uniform vec4 a[20]; gl_FragColor =
* a[i]", we'll temporarily generate 4 vec4 loads from offset i * 4, and
* CSE can later notice that those loads are all the same and eliminate
* the redundant ones.
*/
fs_reg vec4_offset = fs_reg(this, glsl_type::int_type);
instructions.push_tail(ADD(vec4_offset,
varying_offset, const_offset & ~3));
int scale = 1;
if (brw->gen == 4 && dispatch_width == 8) {
/* Pre-gen5, we can either use a SIMD8 message that requires (header,
* u, v, r) as parameters, or we can just use the SIMD16 message
* consisting of (header, u). We choose the second, at the cost of a
* longer return length.
*/
scale = 2;
}
enum opcode op;
if (brw->gen >= 7)
op = FS_OPCODE_VARYING_PULL_CONSTANT_LOAD_GEN7;
else
op = FS_OPCODE_VARYING_PULL_CONSTANT_LOAD;
fs_reg vec4_result = fs_reg(GRF, virtual_grf_alloc(4 * scale), dst.type);
inst = new(mem_ctx) fs_inst(op, vec4_result, surf_index, vec4_offset);
inst->regs_written = 4 * scale;
instructions.push_tail(inst);
if (brw->gen < 7) {
inst->base_mrf = 13;
inst->header_present = true;
if (brw->gen == 4)
inst->mlen = 3;
else
inst->mlen = 1 + dispatch_width / 8;
}
vec4_result.reg_offset += (const_offset & 3) * scale;
instructions.push_tail(MOV(dst, vec4_result));
return instructions;
}
/**
* A helper for MOV generation for fixing up broken hardware SEND dependency
* handling.
*/
fs_inst *
fs_visitor::DEP_RESOLVE_MOV(int grf)
{
fs_inst *inst = MOV(brw_null_reg(), fs_reg(GRF, grf, BRW_REGISTER_TYPE_F));
inst->ir = NULL;
inst->annotation = "send dependency resolve";
/* The caller always wants uncompressed to emit the minimal extra
* dependencies, and to avoid having to deal with aligning its regs to 2.
*/
inst->force_uncompressed = true;
return inst;
}
bool
fs_inst::equals(fs_inst *inst)
{
return (opcode == inst->opcode &&
dst.equals(inst->dst) &&
src[0].equals(inst->src[0]) &&
src[1].equals(inst->src[1]) &&
src[2].equals(inst->src[2]) &&
saturate == inst->saturate &&
predicate == inst->predicate &&
conditional_mod == inst->conditional_mod &&
mlen == inst->mlen &&
base_mrf == inst->base_mrf &&
sampler == inst->sampler &&
target == inst->target &&
eot == inst->eot &&
header_present == inst->header_present &&
shadow_compare == inst->shadow_compare &&
offset == inst->offset);
}
bool
fs_inst::overwrites_reg(const fs_reg ®)
{
return (reg.file == dst.file &&
reg.reg == dst.reg &&
reg.reg_offset >= dst.reg_offset &&
reg.reg_offset < dst.reg_offset + regs_written);
}
bool
fs_inst::is_send_from_grf()
{
return (opcode == FS_OPCODE_VARYING_PULL_CONSTANT_LOAD_GEN7 ||
opcode == SHADER_OPCODE_SHADER_TIME_ADD ||
(opcode == FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD &&
src[1].file == GRF));
}
bool
fs_visitor::can_do_source_mods(fs_inst *inst)
{
if (brw->gen == 6 && inst->is_math())
return false;
if (inst->is_send_from_grf())
return false;
return true;
}
void
fs_reg::init()
{
memset(this, 0, sizeof(*this));
this->smear = -1;
}
/** Generic unset register constructor. */
fs_reg::fs_reg()
{
init();
this->file = BAD_FILE;
}
/** Immediate value constructor. */
fs_reg::fs_reg(float f)
{
init();
this->file = IMM;
this->type = BRW_REGISTER_TYPE_F;
this->imm.f = f;
}
/** Immediate value constructor. */
fs_reg::fs_reg(int32_t i)
{
init();
this->file = IMM;
this->type = BRW_REGISTER_TYPE_D;
this->imm.i = i;
}
/** Immediate value constructor. */
fs_reg::fs_reg(uint32_t u)
{
init();
this->file = IMM;
this->type = BRW_REGISTER_TYPE_UD;
this->imm.u = u;
}
/** Fixed brw_reg Immediate value constructor. */
fs_reg::fs_reg(struct brw_reg fixed_hw_reg)
{
init();
this->file = HW_REG;
this->fixed_hw_reg = fixed_hw_reg;
this->type = fixed_hw_reg.type;
}
bool
fs_reg::equals(const fs_reg &r) const
{
return (file == r.file &&
reg == r.reg &&
reg_offset == r.reg_offset &&
type == r.type &&
negate == r.negate &&
abs == r.abs &&
!reladdr && !r.reladdr &&
memcmp(&fixed_hw_reg, &r.fixed_hw_reg,
sizeof(fixed_hw_reg)) == 0 &&
smear == r.smear &&
imm.u == r.imm.u);
}
bool
fs_reg::is_zero() const
{
if (file != IMM)
return false;
return type == BRW_REGISTER_TYPE_F ? imm.f == 0.0 : imm.i == 0;
}
bool
fs_reg::is_one() const
{
if (file != IMM)
return false;
return type == BRW_REGISTER_TYPE_F ? imm.f == 1.0 : imm.i == 1;
}
bool
fs_reg::is_valid_3src() const
{
return file == GRF || file == UNIFORM;
}
int
fs_visitor::type_size(const struct glsl_type *type)
{
unsigned int size, i;
switch (type->base_type) {
case GLSL_TYPE_UINT:
case GLSL_TYPE_INT:
case GLSL_TYPE_FLOAT:
case GLSL_TYPE_BOOL:
return type->components();
case GLSL_TYPE_ARRAY:
return type_size(type->fields.array) * type->length;
case GLSL_TYPE_STRUCT:
size = 0;
for (i = 0; i < type->length; i++) {
size += type_size(type->fields.structure[i].type);
}
return size;
case GLSL_TYPE_SAMPLER:
/* Samplers take up no register space, since they're baked in at
* link time.
*/
return 0;
case GLSL_TYPE_VOID:
case GLSL_TYPE_ERROR:
case GLSL_TYPE_INTERFACE:
assert(!"not reached");
break;
}
return 0;
}
fs_reg
fs_visitor::get_timestamp()
{
assert(brw->gen >= 7);
fs_reg ts = fs_reg(retype(brw_vec1_reg(BRW_ARCHITECTURE_REGISTER_FILE,
BRW_ARF_TIMESTAMP,
0),
BRW_REGISTER_TYPE_UD));
fs_reg dst = fs_reg(this, glsl_type::uint_type);
fs_inst *mov = emit(MOV(dst, ts));
/* We want to read the 3 fields we care about (mostly field 0, but also 2)
* even if it's not enabled in the dispatch.
*/
mov->force_writemask_all = true;
mov->force_uncompressed = true;
/* The caller wants the low 32 bits of the timestamp. Since it's running
* at the GPU clock rate of ~1.2ghz, it will roll over every ~3 seconds,
* which is plenty of time for our purposes. It is identical across the
* EUs, but since it's tracking GPU core speed it will increment at a
* varying rate as render P-states change.
*
* The caller could also check if render P-states have changed (or anything
* else that might disrupt timing) by setting smear to 2 and checking if
* that field is != 0.
*/
dst.smear = 0;
return dst;
}
void
fs_visitor::emit_shader_time_begin()
{
current_annotation = "shader time start";
shader_start_time = get_timestamp();
}
void
fs_visitor::emit_shader_time_end()
{
current_annotation = "shader time end";
enum shader_time_shader_type type, written_type, reset_type;
if (dispatch_width == 8) {
type = ST_FS8;
written_type = ST_FS8_WRITTEN;
reset_type = ST_FS8_RESET;
} else {
assert(dispatch_width == 16);
type = ST_FS16;
written_type = ST_FS16_WRITTEN;
reset_type = ST_FS16_RESET;
}
fs_reg shader_end_time = get_timestamp();
/* Check that there weren't any timestamp reset events (assuming these
* were the only two timestamp reads that happened).
*/
fs_reg reset = shader_end_time;
reset.smear = 2;
fs_inst *test = emit(AND(reg_null_d, reset, fs_reg(1u)));
test->conditional_mod = BRW_CONDITIONAL_Z;
emit(IF(BRW_PREDICATE_NORMAL));
push_force_uncompressed();
fs_reg start = shader_start_time;
start.negate = true;
fs_reg diff = fs_reg(this, glsl_type::uint_type);
emit(ADD(diff, start, shader_end_time));
/* If there were no instructions between the two timestamp gets, the diff
* is 2 cycles. Remove that overhead, so I can forget about that when
* trying to determine the time taken for single instructions.
*/
emit(ADD(diff, diff, fs_reg(-2u)));
emit_shader_time_write(type, diff);
emit_shader_time_write(written_type, fs_reg(1u));
emit(BRW_OPCODE_ELSE);
emit_shader_time_write(reset_type, fs_reg(1u));
emit(BRW_OPCODE_ENDIF);
pop_force_uncompressed();
}
void
fs_visitor::emit_shader_time_write(enum shader_time_shader_type type,
fs_reg value)
{
int shader_time_index =
brw_get_shader_time_index(brw, shader_prog, &fp->Base, type);
fs_reg offset = fs_reg(shader_time_index * SHADER_TIME_STRIDE);
fs_reg payload;
if (dispatch_width == 8)
payload = fs_reg(this, glsl_type::uvec2_type);
else
payload = fs_reg(this, glsl_type::uint_type);
emit(fs_inst(SHADER_OPCODE_SHADER_TIME_ADD,
fs_reg(), payload, offset, value));
}
void
fs_visitor::fail(const char *format, ...)
{
va_list va;
char *msg;
if (failed)
return;
failed = true;
va_start(va, format);
msg = ralloc_vasprintf(mem_ctx, format, va);
va_end(va);
msg = ralloc_asprintf(mem_ctx, "FS compile failed: %s\n", msg);
this->fail_msg = msg;
if (INTEL_DEBUG & DEBUG_WM) {
fprintf(stderr, "%s", msg);
}
}
fs_inst *
fs_visitor::emit(enum opcode opcode)
{
return emit(fs_inst(opcode));
}
fs_inst *
fs_visitor::emit(enum opcode opcode, fs_reg dst)
{
return emit(fs_inst(opcode, dst));
}
fs_inst *
fs_visitor::emit(enum opcode opcode, fs_reg dst, fs_reg src0)
{
return emit(fs_inst(opcode, dst, src0));
}
fs_inst *
fs_visitor::emit(enum opcode opcode, fs_reg dst, fs_reg src0, fs_reg src1)
{
return emit(fs_inst(opcode, dst, src0, src1));
}
fs_inst *
fs_visitor::emit(enum opcode opcode, fs_reg dst,
fs_reg src0, fs_reg src1, fs_reg src2)
{
return emit(fs_inst(opcode, dst, src0, src1, src2));
}
void
fs_visitor::push_force_uncompressed()
{
force_uncompressed_stack++;
}
void
fs_visitor::pop_force_uncompressed()
{
force_uncompressed_stack--;
assert(force_uncompressed_stack >= 0);
}
void
fs_visitor::push_force_sechalf()
{
force_sechalf_stack++;
}
void
fs_visitor::pop_force_sechalf()
{
force_sechalf_stack--;
assert(force_sechalf_stack >= 0);
}
/**
* Returns true if the instruction has a flag that means it won't
* update an entire destination register.
*
* For example, dead code elimination and live variable analysis want to know
* when a write to a variable screens off any preceding values that were in
* it.
*/
bool
fs_inst::is_partial_write()
{
return (this->predicate ||
this->force_uncompressed ||
this->force_sechalf);
}
/**
* Returns how many MRFs an FS opcode will write over.
*
* Note that this is not the 0 or 1 implied writes in an actual gen
* instruction -- the FS opcodes often generate MOVs in addition.
*/
int
fs_visitor::implied_mrf_writes(fs_inst *inst)
{
if (inst->mlen == 0)
return 0;
switch (inst->opcode) {
case SHADER_OPCODE_RCP:
case SHADER_OPCODE_RSQ:
case SHADER_OPCODE_SQRT:
case SHADER_OPCODE_EXP2:
case SHADER_OPCODE_LOG2:
case SHADER_OPCODE_SIN:
case SHADER_OPCODE_COS:
return 1 * dispatch_width / 8;
case SHADER_OPCODE_POW:
case SHADER_OPCODE_INT_QUOTIENT:
case SHADER_OPCODE_INT_REMAINDER:
return 2 * dispatch_width / 8;
case SHADER_OPCODE_TEX:
case FS_OPCODE_TXB:
case SHADER_OPCODE_TXD:
case SHADER_OPCODE_TXF:
case SHADER_OPCODE_TXF_MS:
case SHADER_OPCODE_TXL:
case SHADER_OPCODE_TXS:
case SHADER_OPCODE_LOD:
return 1;
case FS_OPCODE_FB_WRITE:
return 2;
case FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD:
case FS_OPCODE_UNSPILL:
return 1;
case FS_OPCODE_VARYING_PULL_CONSTANT_LOAD:
return inst->mlen;
case FS_OPCODE_SPILL:
return 2;
default:
assert(!"not reached");
return inst->mlen;
}
}
int
fs_visitor::virtual_grf_alloc(int size)
{
if (virtual_grf_array_size <= virtual_grf_count) {
if (virtual_grf_array_size == 0)
virtual_grf_array_size = 16;
else
virtual_grf_array_size *= 2;
virtual_grf_sizes = reralloc(mem_ctx, virtual_grf_sizes, int,
virtual_grf_array_size);
}
virtual_grf_sizes[virtual_grf_count] = size;
return virtual_grf_count++;
}
/** Fixed HW reg constructor. */
fs_reg::fs_reg(enum register_file file, int reg)
{
init();
this->file = file;
this->reg = reg;
this->type = BRW_REGISTER_TYPE_F;
}
/** Fixed HW reg constructor. */
fs_reg::fs_reg(enum register_file file, int reg, uint32_t type)
{
init();
this->file = file;
this->reg = reg;
this->type = type;
}
/** Automatic reg constructor. */
fs_reg::fs_reg(class fs_visitor *v, const struct glsl_type *type)
{
init();
this->file = GRF;
this->reg = v->virtual_grf_alloc(v->type_size(type));
this->reg_offset = 0;
this->type = brw_type_for_base_type(type);
}
fs_reg *
fs_visitor::variable_storage(ir_variable *var)
{
return (fs_reg *)hash_table_find(this->variable_ht, var);
}
void
import_uniforms_callback(const void *key,
void *data,
void *closure)
{
struct hash_table *dst_ht = (struct hash_table *)closure;
const fs_reg *reg = (const fs_reg *)data;
if (reg->file != UNIFORM)
return;
hash_table_insert(dst_ht, data, key);
}
/* For 16-wide, we need to follow from the uniform setup of 8-wide dispatch.
* This brings in those uniform definitions
*/
void
fs_visitor::import_uniforms(fs_visitor *v)
{
hash_table_call_foreach(v->variable_ht,
import_uniforms_callback,
variable_ht);
this->params_remap = v->params_remap;
this->nr_params_remap = v->nr_params_remap;
}
/* Our support for uniforms is piggy-backed on the struct
* gl_fragment_program, because that's where the values actually
* get stored, rather than in some global gl_shader_program uniform
* store.
*/
void
fs_visitor::setup_uniform_values(ir_variable *ir)
{
int namelen = strlen(ir->name);
/* The data for our (non-builtin) uniforms is stored in a series of
* gl_uniform_driver_storage structs for each subcomponent that
* glGetUniformLocation() could name. We know it's been set up in the same
* order we'd walk the type, so walk the list of storage and find anything
* with our name, or the prefix of a component that starts with our name.
*/
unsigned params_before = c->prog_data.nr_params;
for (unsigned u = 0; u < shader_prog->NumUserUniformStorage; u++) {
struct gl_uniform_storage *storage = &shader_prog->UniformStorage[u];
if (strncmp(ir->name, storage->name, namelen) != 0 ||
(storage->name[namelen] != 0 &&
storage->name[namelen] != '.' &&
storage->name[namelen] != '[')) {
continue;
}
unsigned slots = storage->type->component_slots();
if (storage->array_elements)
slots *= storage->array_elements;
for (unsigned i = 0; i < slots; i++) {
c->prog_data.param[c->prog_data.nr_params++] =
&storage->storage[i].f;
}
}
/* Make sure we actually initialized the right amount of stuff here. */
assert(params_before + ir->type->component_slots() ==
c->prog_data.nr_params);
(void)params_before;
}
/* Our support for builtin uniforms is even scarier than non-builtin.
* It sits on top of the PROG_STATE_VAR parameters that are
* automatically updated from GL context state.
*/
void
fs_visitor::setup_builtin_uniform_values(ir_variable *ir)
{
const ir_state_slot *const slots = ir->state_slots;
assert(ir->state_slots != NULL);
for (unsigned int i = 0; i < ir->num_state_slots; i++) {
/* This state reference has already been setup by ir_to_mesa, but we'll
* get the same index back here.
*/
int index = _mesa_add_state_reference(this->fp->Base.Parameters,
(gl_state_index *)slots[i].tokens);
/* Add each of the unique swizzles of the element as a parameter.
* This'll end up matching the expected layout of the
* array/matrix/structure we're trying to fill in.
*/
int last_swiz = -1;
for (unsigned int j = 0; j < 4; j++) {
int swiz = GET_SWZ(slots[i].swizzle, j);
if (swiz == last_swiz)
break;
last_swiz = swiz;
c->prog_data.param[c->prog_data.nr_params++] =
&fp->Base.Parameters->ParameterValues[index][swiz].f;
}
}
}
fs_reg *
fs_visitor::emit_fragcoord_interpolation(ir_variable *ir)
{
fs_reg *reg = new(this->mem_ctx) fs_reg(this, ir->type);
fs_reg wpos = *reg;
bool flip = !ir->origin_upper_left ^ c->key.render_to_fbo;
/* gl_FragCoord.x */
if (ir->pixel_center_integer) {
emit(MOV(wpos, this->pixel_x));
} else {
emit(ADD(wpos, this->pixel_x, fs_reg(0.5f)));
}
wpos.reg_offset++;
/* gl_FragCoord.y */
if (!flip && ir->pixel_center_integer) {
emit(MOV(wpos, this->pixel_y));
} else {
fs_reg pixel_y = this->pixel_y;
float offset = (ir->pixel_center_integer ? 0.0 : 0.5);
if (flip) {
pixel_y.negate = true;
offset += c->key.drawable_height - 1.0;
}
emit(ADD(wpos, pixel_y, fs_reg(offset)));
}
wpos.reg_offset++;
/* gl_FragCoord.z */
if (brw->gen >= 6) {
emit(MOV(wpos, fs_reg(brw_vec8_grf(c->source_depth_reg, 0))));
} else {
emit(FS_OPCODE_LINTERP, wpos,
this->delta_x[BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC],
this->delta_y[BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC],
interp_reg(VARYING_SLOT_POS, 2));
}
wpos.reg_offset++;
/* gl_FragCoord.w: Already set up in emit_interpolation */
emit(BRW_OPCODE_MOV, wpos, this->wpos_w);
return reg;
}
fs_inst *
fs_visitor::emit_linterp(const fs_reg &attr, const fs_reg &interp,
glsl_interp_qualifier interpolation_mode,
bool is_centroid)
{
brw_wm_barycentric_interp_mode barycoord_mode;
if (brw->gen >= 6) {
if (is_centroid) {
if (interpolation_mode == INTERP_QUALIFIER_SMOOTH)
barycoord_mode = BRW_WM_PERSPECTIVE_CENTROID_BARYCENTRIC;
else
barycoord_mode = BRW_WM_NONPERSPECTIVE_CENTROID_BARYCENTRIC;
} else {
if (interpolation_mode == INTERP_QUALIFIER_SMOOTH)
barycoord_mode = BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC;
else
barycoord_mode = BRW_WM_NONPERSPECTIVE_PIXEL_BARYCENTRIC;
}
} else {
/* On Ironlake and below, there is only one interpolation mode.
* Centroid interpolation doesn't mean anything on this hardware --
* there is no multisampling.
*/
barycoord_mode = BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC;
}
return emit(FS_OPCODE_LINTERP, attr,
this->delta_x[barycoord_mode],
this->delta_y[barycoord_mode], interp);
}
fs_reg *
fs_visitor::emit_general_interpolation(ir_variable *ir)
{
fs_reg *reg = new(this->mem_ctx) fs_reg(this, ir->type);
reg->type = brw_type_for_base_type(ir->type->get_scalar_type());
fs_reg attr = *reg;
unsigned int array_elements;
const glsl_type *type;
if (ir->type->is_array()) {
array_elements = ir->type->length;
if (array_elements == 0) {
fail("dereferenced array '%s' has length 0\n", ir->name);
}
type = ir->type->fields.array;
} else {
array_elements = 1;
type = ir->type;
}
glsl_interp_qualifier interpolation_mode =
ir->determine_interpolation_mode(c->key.flat_shade);
int location = ir->location;
for (unsigned int i = 0; i < array_elements; i++) {
for (unsigned int j = 0; j < type->matrix_columns; j++) {
if (urb_setup[location] == -1) {
/* If there's no incoming setup data for this slot, don't
* emit interpolation for it.
*/
attr.reg_offset += type->vector_elements;
location++;
continue;
}
if (interpolation_mode == INTERP_QUALIFIER_FLAT) {
/* Constant interpolation (flat shading) case. The SF has
* handed us defined values in only the constant offset
* field of the setup reg.
*/
for (unsigned int k = 0; k < type->vector_elements; k++) {
struct brw_reg interp = interp_reg(location, k);
interp = suboffset(interp, 3);
interp.type = reg->type;
emit(FS_OPCODE_CINTERP, attr, fs_reg(interp));
attr.reg_offset++;
}
} else {
/* Smooth/noperspective interpolation case. */
for (unsigned int k = 0; k < type->vector_elements; k++) {
/* FINISHME: At some point we probably want to push
* this farther by giving similar treatment to the
* other potentially constant components of the
* attribute, as well as making brw_vs_constval.c
* handle varyings other than gl_TexCoord.
*/
struct brw_reg interp = interp_reg(location, k);
emit_linterp(attr, fs_reg(interp), interpolation_mode,
ir->centroid);
if (brw->needs_unlit_centroid_workaround && ir->centroid) {
/* Get the pixel/sample mask into f0 so that we know
* which pixels are lit. Then, for each channel that is
* unlit, replace the centroid data with non-centroid
* data.
*/
emit(FS_OPCODE_MOV_DISPATCH_TO_FLAGS);
fs_inst *inst = emit_linterp(attr, fs_reg(interp),
interpolation_mode, false);
inst->predicate = BRW_PREDICATE_NORMAL;
inst->predicate_inverse = true;
}
if (brw->gen < 6) {
emit(BRW_OPCODE_MUL, attr, attr, this->pixel_w);
}
attr.reg_offset++;
}
}
location++;
}
}
return reg;
}
fs_reg *
fs_visitor::emit_frontfacing_interpolation(ir_variable *ir)
{
fs_reg *reg = new(this->mem_ctx) fs_reg(this, ir->type);
/* The frontfacing comes in as a bit in the thread payload. */
if (brw->gen >= 6) {
emit(BRW_OPCODE_ASR, *reg,
fs_reg(retype(brw_vec1_grf(0, 0), BRW_REGISTER_TYPE_D)),
fs_reg(15));
emit(BRW_OPCODE_NOT, *reg, *reg);
emit(BRW_OPCODE_AND, *reg, *reg, fs_reg(1));
} else {
struct brw_reg r1_6ud = retype(brw_vec1_grf(1, 6), BRW_REGISTER_TYPE_UD);
/* bit 31 is "primitive is back face", so checking < (1 << 31) gives
* us front face
*/
emit(CMP(*reg, fs_reg(r1_6ud), fs_reg(1u << 31), BRW_CONDITIONAL_L));
emit(BRW_OPCODE_AND, *reg, *reg, fs_reg(1u));
}
return reg;
}
fs_reg
fs_visitor::fix_math_operand(fs_reg src)
{
/* Can't do hstride == 0 args on gen6 math, so expand it out. We
* might be able to do better by doing execsize = 1 math and then
* expanding that result out, but we would need to be careful with
* masking.
*
* The hardware ignores source modifiers (negate and abs) on math
* instructions, so we also move to a temp to set those up.
*/
if (brw->gen == 6 && src.file != UNIFORM && src.file != IMM &&
!src.abs && !src.negate)
return src;
/* Gen7 relaxes most of the above restrictions, but still can't use IMM
* operands to math
*/
if (brw->gen >= 7 && src.file != IMM)
return src;
fs_reg expanded = fs_reg(this, glsl_type::float_type);
expanded.type = src.type;
emit(BRW_OPCODE_MOV, expanded, src);
return expanded;
}
fs_inst *
fs_visitor::emit_math(enum opcode opcode, fs_reg dst, fs_reg src)
{
switch (opcode) {
case SHADER_OPCODE_RCP:
case SHADER_OPCODE_RSQ:
case SHADER_OPCODE_SQRT:
case SHADER_OPCODE_EXP2:
case SHADER_OPCODE_LOG2:
case SHADER_OPCODE_SIN:
case SHADER_OPCODE_COS:
break;
default:
assert(!"not reached: bad math opcode");
return NULL;
}
/* Can't do hstride == 0 args to gen6 math, so expand it out. We
* might be able to do better by doing execsize = 1 math and then
* expanding that result out, but we would need to be careful with
* masking.
*
* Gen 6 hardware ignores source modifiers (negate and abs) on math
* instructions, so we also move to a temp to set those up.
*/
if (brw->gen >= 6)
src = fix_math_operand(src);
fs_inst *inst = emit(opcode, dst, src);
if (brw->gen < 6) {
inst->base_mrf = 2;
inst->mlen = dispatch_width / 8;
}
return inst;
}
fs_inst *
fs_visitor::emit_math(enum opcode opcode, fs_reg dst, fs_reg src0, fs_reg src1)
{
int base_mrf = 2;
fs_inst *inst;
switch (opcode) {
case SHADER_OPCODE_INT_QUOTIENT:
case SHADER_OPCODE_INT_REMAINDER:
if (brw->gen >= 7 && dispatch_width == 16)
fail("16-wide INTDIV unsupported\n");
break;
case SHADER_OPCODE_POW:
break;
default:
assert(!"not reached: unsupported binary math opcode.");
return NULL;
}
if (brw->gen >= 6) {
src0 = fix_math_operand(src0);
src1 = fix_math_operand(src1);
inst = emit(opcode, dst, src0, src1);
} else {
/* From the Ironlake PRM, Volume 4, Part 1, Section 6.1.13
* "Message Payload":
*
* "Operand0[7]. For the INT DIV functions, this operand is the
* denominator."
* ...
* "Operand1[7]. For the INT DIV functions, this operand is the
* numerator."
*/
bool is_int_div = opcode != SHADER_OPCODE_POW;
fs_reg &op0 = is_int_div ? src1 : src0;
fs_reg &op1 = is_int_div ? src0 : src1;
emit(BRW_OPCODE_MOV, fs_reg(MRF, base_mrf + 1, op1.type), op1);
inst = emit(opcode, dst, op0, reg_null_f);
inst->base_mrf = base_mrf;
inst->mlen = 2 * dispatch_width / 8;
}
return inst;
}
void
fs_visitor::assign_curb_setup()
{
c->prog_data.curb_read_length = ALIGN(c->prog_data.nr_params, 8) / 8;
if (dispatch_width == 8) {
c->prog_data.first_curbe_grf = c->nr_payload_regs;
} else {
c->prog_data.first_curbe_grf_16 = c->nr_payload_regs;
}
/* Map the offsets in the UNIFORM file to fixed HW regs. */
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
for (unsigned int i = 0; i < 3; i++) {
if (inst->src[i].file == UNIFORM) {
int constant_nr = inst->src[i].reg + inst->src[i].reg_offset;
struct brw_reg brw_reg = brw_vec1_grf(c->nr_payload_regs +
constant_nr / 8,
constant_nr % 8);
inst->src[i].file = HW_REG;
inst->src[i].fixed_hw_reg = retype(brw_reg, inst->src[i].type);
}
}
}
}
void
fs_visitor::calculate_urb_setup()
{
for (unsigned int i = 0; i < VARYING_SLOT_MAX; i++) {
urb_setup[i] = -1;
}
int urb_next = 0;
/* Figure out where each of the incoming setup attributes lands. */
if (brw->gen >= 6) {
for (unsigned int i = 0; i < VARYING_SLOT_MAX; i++) {
if (fp->Base.InputsRead & BITFIELD64_BIT(i)) {
urb_setup[i] = urb_next++;
}
}
} else {
/* FINISHME: The sf doesn't map VS->FS inputs for us very well. */
for (unsigned int i = 0; i < VARYING_SLOT_MAX; i++) {
/* Point size is packed into the header, not as a general attribute */
if (i == VARYING_SLOT_PSIZ)
continue;
if (c->key.input_slots_valid & BITFIELD64_BIT(i)) {
/* The back color slot is skipped when the front color is
* also written to. In addition, some slots can be
* written in the vertex shader and not read in the
* fragment shader. So the register number must always be
* incremented, mapped or not.
*/
if (_mesa_varying_slot_in_fs((gl_varying_slot) i))
urb_setup[i] = urb_next;
urb_next++;
}
}
/*
* It's a FS only attribute, and we did interpolation for this attribute
* in SF thread. So, count it here, too.
*
* See compile_sf_prog() for more info.
*/
if (fp->Base.InputsRead & BITFIELD64_BIT(VARYING_SLOT_PNTC))
urb_setup[VARYING_SLOT_PNTC] = urb_next++;
}
/* Each attribute is 4 setup channels, each of which is half a reg. */
c->prog_data.urb_read_length = urb_next * 2;
}
void
fs_visitor::assign_urb_setup()
{
int urb_start = c->nr_payload_regs + c->prog_data.curb_read_length;
/* Offset all the urb_setup[] index by the actual position of the
* setup regs, now that the location of the constants has been chosen.
*/
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
if (inst->opcode == FS_OPCODE_LINTERP) {
assert(inst->src[2].file == HW_REG);
inst->src[2].fixed_hw_reg.nr += urb_start;
}
if (inst->opcode == FS_OPCODE_CINTERP) {
assert(inst->src[0].file == HW_REG);
inst->src[0].fixed_hw_reg.nr += urb_start;
}
}
this->first_non_payload_grf = urb_start + c->prog_data.urb_read_length;
}
/**
* Split large virtual GRFs into separate components if we can.
*
* This is mostly duplicated with what brw_fs_vector_splitting does,
* but that's really conservative because it's afraid of doing
* splitting that doesn't result in real progress after the rest of
* the optimization phases, which would cause infinite looping in
* optimization. We can do it once here, safely. This also has the
* opportunity to split interpolated values, or maybe even uniforms,
* which we don't have at the IR level.
*
* We want to split, because virtual GRFs are what we register
* allocate and spill (due to contiguousness requirements for some
* instructions), and they're what we naturally generate in the
* codegen process, but most virtual GRFs don't actually need to be
* contiguous sets of GRFs. If we split, we'll end up with reduced
* live intervals and better dead code elimination and coalescing.
*/
void
fs_visitor::split_virtual_grfs()
{
int num_vars = this->virtual_grf_count;
bool split_grf[num_vars];
int new_virtual_grf[num_vars];
/* Try to split anything > 0 sized. */
for (int i = 0; i < num_vars; i++) {
if (this->virtual_grf_sizes[i] != 1)
split_grf[i] = true;
else
split_grf[i] = false;
}
if (brw->has_pln &&
this->delta_x[BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC].file == GRF) {
/* PLN opcodes rely on the delta_xy being contiguous. We only have to
* check this for BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC, because prior to
* Gen6, that was the only supported interpolation mode, and since Gen6,
* delta_x and delta_y are in fixed hardware registers.
*/
split_grf[this->delta_x[BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC].reg] =
false;
}
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
/* If there's a SEND message that requires contiguous destination
* registers, no splitting is allowed.
*/
if (inst->regs_written > 1) {
split_grf[inst->dst.reg] = false;
}
/* If we're sending from a GRF, don't split it, on the assumption that
* the send is reading the whole thing.
*/
if (inst->is_send_from_grf()) {
for (int i = 0; i < 3; i++) {
if (inst->src[i].file == GRF) {
split_grf[inst->src[i].reg] = false;
}
}
}
}
/* Allocate new space for split regs. Note that the virtual
* numbers will be contiguous.
*/
for (int i = 0; i < num_vars; i++) {
if (split_grf[i]) {
new_virtual_grf[i] = virtual_grf_alloc(1);
for (int j = 2; j < this->virtual_grf_sizes[i]; j++) {
int reg = virtual_grf_alloc(1);
assert(reg == new_virtual_grf[i] + j - 1);
(void) reg;
}
this->virtual_grf_sizes[i] = 1;
}
}
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
if (inst->dst.file == GRF &&
split_grf[inst->dst.reg] &&
inst->dst.reg_offset != 0) {
inst->dst.reg = (new_virtual_grf[inst->dst.reg] +
inst->dst.reg_offset - 1);
inst->dst.reg_offset = 0;
}
for (int i = 0; i < 3; i++) {
if (inst->src[i].file == GRF &&
split_grf[inst->src[i].reg] &&
inst->src[i].reg_offset != 0) {
inst->src[i].reg = (new_virtual_grf[inst->src[i].reg] +
inst->src[i].reg_offset - 1);
inst->src[i].reg_offset = 0;
}
}
}
this->live_intervals_valid = false;
}
/**
* Remove unused virtual GRFs and compact the virtual_grf_* arrays.
*
* During code generation, we create tons of temporary variables, many of
* which get immediately killed and are never used again. Yet, in later
* optimization and analysis passes, such as compute_live_intervals, we need
* to loop over all the virtual GRFs. Compacting them can save a lot of
* overhead.
*/
void
fs_visitor::compact_virtual_grfs()
{
/* Mark which virtual GRFs are used, and count how many. */
int remap_table[this->virtual_grf_count];
memset(remap_table, -1, sizeof(remap_table));
foreach_list(node, &this->instructions) {
const fs_inst *inst = (const fs_inst *) node;
if (inst->dst.file == GRF)
remap_table[inst->dst.reg] = 0;
for (int i = 0; i < 3; i++) {
if (inst->src[i].file == GRF)
remap_table[inst->src[i].reg] = 0;
}
}
/* In addition to registers used in instructions, fs_visitor keeps
* direct references to certain special values which must be patched:
*/
fs_reg *special[] = {
&frag_depth, &pixel_x, &pixel_y, &pixel_w, &wpos_w, &dual_src_output,
&outputs[0], &outputs[1], &outputs[2], &outputs[3],
&outputs[4], &outputs[5], &outputs[6], &outputs[7],
&delta_x[0], &delta_x[1], &delta_x[2],
&delta_x[3], &delta_x[4], &delta_x[5],
&delta_y[0], &delta_y[1], &delta_y[2],
&delta_y[3], &delta_y[4], &delta_y[5],
};
STATIC_ASSERT(BRW_WM_BARYCENTRIC_INTERP_MODE_COUNT == 6);
STATIC_ASSERT(BRW_MAX_DRAW_BUFFERS == 8);
/* Treat all special values as used, to be conservative */
for (unsigned i = 0; i < ARRAY_SIZE(special); i++) {
if (special[i]->file == GRF)
remap_table[special[i]->reg] = 0;
}
/* Compact the GRF arrays. */
int new_index = 0;
for (int i = 0; i < this->virtual_grf_count; i++) {
if (remap_table[i] != -1) {
remap_table[i] = new_index;
virtual_grf_sizes[new_index] = virtual_grf_sizes[i];
if (live_intervals_valid) {
virtual_grf_start[new_index] = virtual_grf_start[i];
virtual_grf_end[new_index] = virtual_grf_end[i];
}
++new_index;
}
}
this->virtual_grf_count = new_index;
/* Patch all the instructions to use the newly renumbered registers */
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *) node;
if (inst->dst.file == GRF)
inst->dst.reg = remap_table[inst->dst.reg];
for (int i = 0; i < 3; i++) {
if (inst->src[i].file == GRF)
inst->src[i].reg = remap_table[inst->src[i].reg];
}
}
/* Patch all the references to special values */
for (unsigned i = 0; i < ARRAY_SIZE(special); i++) {
if (special[i]->file == GRF && remap_table[special[i]->reg] != -1)
special[i]->reg = remap_table[special[i]->reg];
}
}
bool
fs_visitor::remove_dead_constants()
{
if (dispatch_width == 8) {
this->params_remap = ralloc_array(mem_ctx, int, c->prog_data.nr_params);
this->nr_params_remap = c->prog_data.nr_params;
for (unsigned int i = 0; i < c->prog_data.nr_params; i++)
this->params_remap[i] = -1;
/* Find which params are still in use. */
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
for (int i = 0; i < 3; i++) {
int constant_nr = inst->src[i].reg + inst->src[i].reg_offset;
if (inst->src[i].file != UNIFORM)
continue;
/* Section 5.11 of the OpenGL 4.3 spec says:
*
* "Out-of-bounds reads return undefined values, which include
* values from other variables of the active program or zero."
*/
if (constant_nr < 0 || constant_nr >= (int)c->prog_data.nr_params) {
constant_nr = 0;
}
/* For now, set this to non-negative. We'll give it the
* actual new number in a moment, in order to keep the
* register numbers nicely ordered.
*/
this->params_remap[constant_nr] = 0;
}
}
/* Figure out what the new numbers for the params will be. At some
* point when we're doing uniform array access, we're going to want
* to keep the distinction between .reg and .reg_offset, but for
* now we don't care.
*/
unsigned int new_nr_params = 0;
for (unsigned int i = 0; i < c->prog_data.nr_params; i++) {
if (this->params_remap[i] != -1) {
this->params_remap[i] = new_nr_params++;
}
}
/* Update the list of params to be uploaded to match our new numbering. */
for (unsigned int i = 0; i < c->prog_data.nr_params; i++) {
int remapped = this->params_remap[i];
if (remapped == -1)
continue;
c->prog_data.param[remapped] = c->prog_data.param[i];
}
c->prog_data.nr_params = new_nr_params;
} else {
/* This should have been generated in the 8-wide pass already. */
assert(this->params_remap);
}
/* Now do the renumbering of the shader to remove unused params. */
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
for (int i = 0; i < 3; i++) {
int constant_nr = inst->src[i].reg + inst->src[i].reg_offset;
if (inst->src[i].file != UNIFORM)
continue;
/* as above alias to 0 */
if (constant_nr < 0 || constant_nr >= (int)this->nr_params_remap) {
constant_nr = 0;
}
assert(this->params_remap[constant_nr] != -1);
inst->src[i].reg = this->params_remap[constant_nr];
inst->src[i].reg_offset = 0;
}
}
return true;
}
/*
* Implements array access of uniforms by inserting a
* PULL_CONSTANT_LOAD instruction.
*
* Unlike temporary GRF array access (where we don't support it due to
* the difficulty of doing relative addressing on instruction
* destinations), we could potentially do array access of uniforms
* that were loaded in GRF space as push constants. In real-world
* usage we've seen, though, the arrays being used are always larger
* than we could load as push constants, so just always move all
* uniform array access out to a pull constant buffer.
*/
void
fs_visitor::move_uniform_array_access_to_pull_constants()
{
int pull_constant_loc[c->prog_data.nr_params];
for (unsigned int i = 0; i < c->prog_data.nr_params; i++) {
pull_constant_loc[i] = -1;
}
/* Walk through and find array access of uniforms. Put a copy of that
* uniform in the pull constant buffer.
*
* Note that we don't move constant-indexed accesses to arrays. No
* testing has been done of the performance impact of this choice.
*/
foreach_list_safe(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
for (int i = 0 ; i < 3; i++) {
if (inst->src[i].file != UNIFORM || !inst->src[i].reladdr)
continue;
int uniform = inst->src[i].reg;
/* If this array isn't already present in the pull constant buffer,
* add it.
*/
if (pull_constant_loc[uniform] == -1) {
const float **values = &c->prog_data.param[uniform];
pull_constant_loc[uniform] = c->prog_data.nr_pull_params;
assert(param_size[uniform]);
for (int j = 0; j < param_size[uniform]; j++) {
c->prog_data.pull_param[c->prog_data.nr_pull_params++] =
values[j];
}
}
/* Set up the annotation tracking for new generated instructions. */
base_ir = inst->ir;
current_annotation = inst->annotation;
fs_reg surf_index = fs_reg((unsigned)SURF_INDEX_FRAG_CONST_BUFFER);
fs_reg temp = fs_reg(this, glsl_type::float_type);
exec_list list = VARYING_PULL_CONSTANT_LOAD(temp,
surf_index,
*inst->src[i].reladdr,
pull_constant_loc[uniform] +
inst->src[i].reg_offset);
inst->insert_before(&list);
inst->src[i].file = temp.file;
inst->src[i].reg = temp.reg;
inst->src[i].reg_offset = temp.reg_offset;
inst->src[i].reladdr = NULL;
}
}
}
/**
* Choose accesses from the UNIFORM file to demote to using the pull
* constant buffer.
*
* We allow a fragment shader to have more than the specified minimum
* maximum number of fragment shader uniform components (64). If
* there are too many of these, they'd fill up all of register space.
* So, this will push some of them out to the pull constant buffer and
* update the program to load them.
*/
void
fs_visitor::setup_pull_constants()
{
/* Only allow 16 registers (128 uniform components) as push constants. */
unsigned int max_uniform_components = 16 * 8;
if (c->prog_data.nr_params <= max_uniform_components)
return;
if (dispatch_width == 16) {
fail("Pull constants not supported in 16-wide\n");
return;
}
/* Just demote the end of the list. We could probably do better
* here, demoting things that are rarely used in the program first.
*/
unsigned int pull_uniform_base = max_uniform_components;
int pull_constant_loc[c->prog_data.nr_params];
for (unsigned int i = 0; i < c->prog_data.nr_params; i++) {
if (i < pull_uniform_base) {
pull_constant_loc[i] = -1;
} else {
pull_constant_loc[i] = -1;
/* If our constant is already being uploaded for reladdr purposes,
* reuse it.
*/
for (unsigned int j = 0; j < c->prog_data.nr_pull_params; j++) {
if (c->prog_data.pull_param[j] == c->prog_data.param[i]) {
pull_constant_loc[i] = j;
break;
}
}
if (pull_constant_loc[i] == -1) {
int pull_index = c->prog_data.nr_pull_params++;
c->prog_data.pull_param[pull_index] = c->prog_data.param[i];
pull_constant_loc[i] = pull_index;;
}
}
}
c->prog_data.nr_params = pull_uniform_base;
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
for (int i = 0; i < 3; i++) {
if (inst->src[i].file != UNIFORM)
continue;
int pull_index = pull_constant_loc[inst->src[i].reg +
inst->src[i].reg_offset];
if (pull_index == -1)
continue;
assert(!inst->src[i].reladdr);
fs_reg dst = fs_reg(this, glsl_type::float_type);
fs_reg index = fs_reg((unsigned)SURF_INDEX_FRAG_CONST_BUFFER);
fs_reg offset = fs_reg((unsigned)(pull_index * 4) & ~15);
fs_inst *pull =
new(mem_ctx) fs_inst(FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD,
dst, index, offset);
pull->ir = inst->ir;
pull->annotation = inst->annotation;
inst->insert_before(pull);
inst->src[i].file = GRF;
inst->src[i].reg = dst.reg;
inst->src[i].reg_offset = 0;
inst->src[i].smear = pull_index & 3;
}
}
}
bool
fs_visitor::opt_algebraic()
{
bool progress = false;
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
switch (inst->opcode) {
case BRW_OPCODE_MUL:
if (inst->src[1].file != IMM)
continue;
/* a * 1.0 = a */
if (inst->src[1].is_one()) {
inst->opcode = BRW_OPCODE_MOV;
inst->src[1] = reg_undef;
progress = true;
break;
}
/* a * 0.0 = 0.0 */
if (inst->src[1].is_zero()) {
inst->opcode = BRW_OPCODE_MOV;
inst->src[0] = inst->src[1];
inst->src[1] = reg_undef;
progress = true;
break;
}
break;
case BRW_OPCODE_ADD:
if (inst->src[1].file != IMM)
continue;
/* a + 0.0 = a */
if (inst->src[1].is_zero()) {
inst->opcode = BRW_OPCODE_MOV;
inst->src[1] = reg_undef;
progress = true;
break;
}
break;
default:
break;
}
}
return progress;
}
/**
* Removes any instructions writing a VGRF where that VGRF is not used by any
* later instruction.
*/
bool
fs_visitor::dead_code_eliminate()
{
bool progress = false;
int pc = 0;
calculate_live_intervals();
foreach_list_safe(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
if (inst->dst.file == GRF) {
assert(this->virtual_grf_end[inst->dst.reg] >= pc);
if (this->virtual_grf_end[inst->dst.reg] == pc) {
inst->remove();
progress = true;
}
}
pc++;
}
if (progress)
live_intervals_valid = false;
return progress;
}
struct dead_code_hash_key
{
int vgrf;
int reg_offset;
};
static bool
dead_code_hash_compare(const void *a, const void *b)
{
return memcmp(a, b, sizeof(struct dead_code_hash_key)) == 0;
}
static void
clear_dead_code_hash(struct hash_table *ht)
{
struct hash_entry *entry;
hash_table_foreach(ht, entry) {
_mesa_hash_table_remove(ht, entry);
}
}
static void
insert_dead_code_hash(struct hash_table *ht,
int vgrf, int reg_offset, fs_inst *inst)
{
/* We don't bother freeing keys, because they'll be GCed with the ht. */
struct dead_code_hash_key *key = ralloc(ht, struct dead_code_hash_key);
key->vgrf = vgrf;
key->reg_offset = reg_offset;
_mesa_hash_table_insert(ht, _mesa_hash_data(key, sizeof(*key)), key, inst);
}
static struct hash_entry *
get_dead_code_hash_entry(struct hash_table *ht, int vgrf, int reg_offset)
{
struct dead_code_hash_key key;
key.vgrf = vgrf;
key.reg_offset = reg_offset;
return _mesa_hash_table_search(ht, _mesa_hash_data(&key, sizeof(key)), &key);
}
static void
remove_dead_code_hash(struct hash_table *ht,
int vgrf, int reg_offset)
{
struct hash_entry *entry = get_dead_code_hash_entry(ht, vgrf, reg_offset);
if (!entry)
return;
_mesa_hash_table_remove(ht, entry);
}
/**
* Walks basic blocks, removing any regs that are written but not read before
* being redefined.
*
* The dead_code_eliminate() function implements a global dead code
* elimination, but it only handles the removing the last write to a register
* if it's never read. This one can handle intermediate writes, but only
* within a basic block.
*/
bool
fs_visitor::dead_code_eliminate_local()
{
struct hash_table *ht;
bool progress = false;
ht = _mesa_hash_table_create(mem_ctx, dead_code_hash_compare);
foreach_list_safe(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
/* At a basic block, empty the HT since we don't understand dataflow
* here.
*/
if (inst->is_control_flow()) {
clear_dead_code_hash(ht);
continue;
}
/* Clear the HT of any instructions that got read. */
for (int i = 0; i < 3; i++) {
fs_reg src = inst->src[i];
if (src.file != GRF)
continue;
int read = 1;
if (inst->is_send_from_grf())
read = virtual_grf_sizes[src.reg] - src.reg_offset;
for (int reg_offset = src.reg_offset;
reg_offset < src.reg_offset + read;
reg_offset++) {
remove_dead_code_hash(ht, src.reg, reg_offset);
}
}
/* Add any update of a GRF to the HT, removing a previous write if it
* wasn't read.
*/
if (inst->dst.file == GRF) {
if (inst->regs_written > 1) {
/* We don't know how to trim channels from an instruction's
* writes, so we can't incrementally remove unread channels from
* it. Just remove whatever it overwrites from the table
*/
for (int i = 0; i < inst->regs_written; i++) {
remove_dead_code_hash(ht,
inst->dst.reg,
inst->dst.reg_offset + i);
}
} else {
struct hash_entry *entry =
get_dead_code_hash_entry(ht, inst->dst.reg,
inst->dst.reg_offset);
if (inst->is_partial_write()) {
/* For a partial write, we can't remove any previous dead code
* candidate, since we're just modifying their result, but we can
* be dead code eliminiated ourselves.
*/
if (entry) {
entry->data = inst;
} else {
insert_dead_code_hash(ht, inst->dst.reg, inst->dst.reg_offset,
inst);
}
} else {
if (entry) {
/* We're completely updating a channel, and there was a
* previous write to the channel that wasn't read. Kill it!
*/
fs_inst *inst = (fs_inst *)entry->data;
inst->remove();
progress = true;
_mesa_hash_table_remove(ht, entry);
}
insert_dead_code_hash(ht, inst->dst.reg, inst->dst.reg_offset,
inst);
}
}
}
}
_mesa_hash_table_destroy(ht, NULL);
if (progress)
live_intervals_valid = false;
return progress;
}
/**
* Implements a second type of register coalescing: This one checks if
* the two regs involved in a raw move don't interfere, in which case
* they can both by stored in the same place and the MOV removed.
*/
bool
fs_visitor::register_coalesce_2()
{
bool progress = false;
calculate_live_intervals();
foreach_list_safe(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
if (inst->opcode != BRW_OPCODE_MOV ||
inst->is_partial_write() ||
inst->saturate ||
inst->src[0].file != GRF ||
inst->src[0].negate ||
inst->src[0].abs ||
inst->src[0].smear != -1 ||
inst->dst.file != GRF ||
inst->dst.type != inst->src[0].type ||
virtual_grf_sizes[inst->src[0].reg] != 1 ||
virtual_grf_interferes(inst->dst.reg, inst->src[0].reg)) {
continue;
}
int reg_from = inst->src[0].reg;
assert(inst->src[0].reg_offset == 0);
int reg_to = inst->dst.reg;
int reg_to_offset = inst->dst.reg_offset;
foreach_list(node, &this->instructions) {
fs_inst *scan_inst = (fs_inst *)node;
if (scan_inst->dst.file == GRF &&
scan_inst->dst.reg == reg_from) {
scan_inst->dst.reg = reg_to;
scan_inst->dst.reg_offset = reg_to_offset;
}
for (int i = 0; i < 3; i++) {
if (scan_inst->src[i].file == GRF &&
scan_inst->src[i].reg == reg_from) {
scan_inst->src[i].reg = reg_to;
scan_inst->src[i].reg_offset = reg_to_offset;
}
}
}
inst->remove();
/* We don't need to recalculate live intervals inside the loop despite
* flagging live_intervals_valid because we only use live intervals for
* the interferes test, and we must have had a situation where the
* intervals were:
*
* from to
* ^
* |
* v
* ^
* |
* v
*
* Some register R that might get coalesced with one of these two could
* only be referencing "to", otherwise "from"'s range would have been
* longer. R's range could also only start at the end of "to" or later,
* otherwise it will conflict with "to" when we try to coalesce "to"
* into Rw anyway.
*/
live_intervals_valid = false;
progress = true;
continue;
}
return progress;
}
bool
fs_visitor::register_coalesce()
{
bool progress = false;
int if_depth = 0;
int loop_depth = 0;
foreach_list_safe(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
/* Make sure that we dominate the instructions we're going to
* scan for interfering with our coalescing, or we won't have
* scanned enough to see if anything interferes with our
* coalescing. We don't dominate the following instructions if
* we're in a loop or an if block.
*/
switch (inst->opcode) {
case BRW_OPCODE_DO:
loop_depth++;
break;
case BRW_OPCODE_WHILE:
loop_depth--;
break;
case BRW_OPCODE_IF:
if_depth++;
break;
case BRW_OPCODE_ENDIF:
if_depth--;
break;
default:
break;
}
if (loop_depth || if_depth)
continue;
if (inst->opcode != BRW_OPCODE_MOV ||
inst->is_partial_write() ||
inst->saturate ||
inst->dst.file != GRF || (inst->src[0].file != GRF &&
inst->src[0].file != UNIFORM)||
inst->dst.type != inst->src[0].type)
continue;
bool has_source_modifiers = (inst->src[0].abs ||
inst->src[0].negate ||
inst->src[0].smear != -1 ||
inst->src[0].file == UNIFORM);
/* Found a move of a GRF to a GRF. Let's see if we can coalesce
* them: check for no writes to either one until the exit of the
* program.
*/
bool interfered = false;
for (fs_inst *scan_inst = (fs_inst *)inst->next;
!scan_inst->is_tail_sentinel();
scan_inst = (fs_inst *)scan_inst->next) {
if (scan_inst->dst.file == GRF) {
if (scan_inst->overwrites_reg(inst->dst) ||
scan_inst->overwrites_reg(inst->src[0])) {
interfered = true;
break;
}
}
if (has_source_modifiers) {
for (int i = 0; i < 3; i++) {
if (scan_inst->src[i].file == GRF &&
scan_inst->src[i].reg == inst->dst.reg &&
scan_inst->src[i].reg_offset == inst->dst.reg_offset &&
inst->dst.type != scan_inst->src[i].type)
{
interfered = true;
break;
}
}
}
/* The gen6 MATH instruction can't handle source modifiers or
* unusual register regions, so avoid coalescing those for
* now. We should do something more specific.
*/
if (has_source_modifiers && !can_do_source_mods(scan_inst)) {
interfered = true;
break;
}
/* The accumulator result appears to get used for the
* conditional modifier generation. When negating a UD
* value, there is a 33rd bit generated for the sign in the
* accumulator value, so now you can't check, for example,
* equality with a 32-bit value. See piglit fs-op-neg-uint.
*/
if (scan_inst->conditional_mod &&
inst->src[0].negate &&
inst->src[0].type == BRW_REGISTER_TYPE_UD) {
interfered = true;
break;
}
}
if (interfered) {
continue;
}
/* Rewrite the later usage to point at the source of the move to
* be removed.
*/
for (fs_inst *scan_inst = inst;
!scan_inst->is_tail_sentinel();
scan_inst = (fs_inst *)scan_inst->next) {
for (int i = 0; i < 3; i++) {
if (scan_inst->src[i].file == GRF &&
scan_inst->src[i].reg == inst->dst.reg &&
scan_inst->src[i].reg_offset == inst->dst.reg_offset) {
fs_reg new_src = inst->src[0];
if (scan_inst->src[i].abs) {
new_src.negate = 0;
new_src.abs = 1;
}
new_src.negate ^= scan_inst->src[i].negate;
scan_inst->src[i] = new_src;
}
}
}
inst->remove();
progress = true;
}
if (progress)
live_intervals_valid = false;
return progress;
}
bool
fs_visitor::compute_to_mrf()
{
bool progress = false;
int next_ip = 0;
calculate_live_intervals();
foreach_list_safe(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
int ip = next_ip;
next_ip++;
if (inst->opcode != BRW_OPCODE_MOV ||
inst->is_partial_write() ||
inst->dst.file != MRF || inst->src[0].file != GRF ||
inst->dst.type != inst->src[0].type ||
inst->src[0].abs || inst->src[0].negate || inst->src[0].smear != -1)
continue;
/* Work out which hardware MRF registers are written by this
* instruction.
*/
int mrf_low = inst->dst.reg & ~BRW_MRF_COMPR4;
int mrf_high;
if (inst->dst.reg & BRW_MRF_COMPR4) {
mrf_high = mrf_low + 4;
} else if (dispatch_width == 16 &&
(!inst->force_uncompressed && !inst->force_sechalf)) {
mrf_high = mrf_low + 1;
} else {
mrf_high = mrf_low;
}
/* Can't compute-to-MRF this GRF if someone else was going to
* read it later.
*/
if (this->virtual_grf_end[inst->src[0].reg] > ip)
continue;
/* Found a move of a GRF to a MRF. Let's see if we can go
* rewrite the thing that made this GRF to write into the MRF.
*/
fs_inst *scan_inst;
for (scan_inst = (fs_inst *)inst->prev;
scan_inst->prev != NULL;
scan_inst = (fs_inst *)scan_inst->prev) {
if (scan_inst->dst.file == GRF &&
scan_inst->dst.reg == inst->src[0].reg) {
/* Found the last thing to write our reg we want to turn
* into a compute-to-MRF.
*/
/* If this one instruction didn't populate all the
* channels, bail. We might be able to rewrite everything
* that writes that reg, but it would require smarter
* tracking to delay the rewriting until complete success.
*/
if (scan_inst->is_partial_write())
break;
/* Things returning more than one register would need us to
* understand coalescing out more than one MOV at a time.
*/
if (scan_inst->regs_written > 1)
break;
/* SEND instructions can't have MRF as a destination. */
if (scan_inst->mlen)
break;
if (brw->gen == 6) {
/* gen6 math instructions must have the destination be
* GRF, so no compute-to-MRF for them.
*/
if (scan_inst->is_math()) {
break;
}
}
if (scan_inst->dst.reg_offset == inst->src[0].reg_offset) {
/* Found the creator of our MRF's source value. */
scan_inst->dst.file = MRF;
scan_inst->dst.reg = inst->dst.reg;
scan_inst->saturate |= inst->saturate;
inst->remove();
progress = true;
}
break;
}
/* We don't handle control flow here. Most computation of
* values that end up in MRFs are shortly before the MRF
* write anyway.
*/
if (scan_inst->is_control_flow() && scan_inst->opcode != BRW_OPCODE_IF)
break;
/* You can't read from an MRF, so if someone else reads our
* MRF's source GRF that we wanted to rewrite, that stops us.
*/
bool interfered = false;
for (int i = 0; i < 3; i++) {
if (scan_inst->src[i].file == GRF &&
scan_inst->src[i].reg == inst->src[0].reg &&
scan_inst->src[i].reg_offset == inst->src[0].reg_offset) {
interfered = true;
}
}
if (interfered)
break;
if (scan_inst->dst.file == MRF) {
/* If somebody else writes our MRF here, we can't
* compute-to-MRF before that.
*/
int scan_mrf_low = scan_inst->dst.reg & ~BRW_MRF_COMPR4;
int scan_mrf_high;
if (scan_inst->dst.reg & BRW_MRF_COMPR4) {
scan_mrf_high = scan_mrf_low + 4;
} else if (dispatch_width == 16 &&
(!scan_inst->force_uncompressed &&
!scan_inst->force_sechalf)) {
scan_mrf_high = scan_mrf_low + 1;
} else {
scan_mrf_high = scan_mrf_low;
}
if (mrf_low == scan_mrf_low ||
mrf_low == scan_mrf_high ||
mrf_high == scan_mrf_low ||
mrf_high == scan_mrf_high) {
break;
}
}
if (scan_inst->mlen > 0) {
/* Found a SEND instruction, which means that there are
* live values in MRFs from base_mrf to base_mrf +
* scan_inst->mlen - 1. Don't go pushing our MRF write up
* above it.
*/
if (mrf_low >= scan_inst->base_mrf &&
mrf_low < scan_inst->base_mrf + scan_inst->mlen) {
break;
}
if (mrf_high >= scan_inst->base_mrf &&
mrf_high < scan_inst->base_mrf + scan_inst->mlen) {
break;
}
}
}
}
if (progress)
live_intervals_valid = false;
return progress;
}
/**
* Walks through basic blocks, looking for repeated MRF writes and
* removing the later ones.
*/
bool
fs_visitor::remove_duplicate_mrf_writes()
{
fs_inst *last_mrf_move[16];
bool progress = false;
/* Need to update the MRF tracking for compressed instructions. */
if (dispatch_width == 16)
return false;
memset(last_mrf_move, 0, sizeof(last_mrf_move));
foreach_list_safe(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
if (inst->is_control_flow()) {
memset(last_mrf_move, 0, sizeof(last_mrf_move));
}
if (inst->opcode == BRW_OPCODE_MOV &&
inst->dst.file == MRF) {
fs_inst *prev_inst = last_mrf_move[inst->dst.reg];
if (prev_inst && inst->equals(prev_inst)) {
inst->remove();
progress = true;
continue;
}
}
/* Clear out the last-write records for MRFs that were overwritten. */
if (inst->dst.file == MRF) {
last_mrf_move[inst->dst.reg] = NULL;
}
if (inst->mlen > 0) {
/* Found a SEND instruction, which will include two or fewer
* implied MRF writes. We could do better here.
*/
for (int i = 0; i < implied_mrf_writes(inst); i++) {
last_mrf_move[inst->base_mrf + i] = NULL;
}
}
/* Clear out any MRF move records whose sources got overwritten. */
if (inst->dst.file == GRF) {
for (unsigned int i = 0; i < Elements(last_mrf_move); i++) {
if (last_mrf_move[i] &&
last_mrf_move[i]->src[0].reg == inst->dst.reg) {
last_mrf_move[i] = NULL;
}
}
}
if (inst->opcode == BRW_OPCODE_MOV &&
inst->dst.file == MRF &&
inst->src[0].file == GRF &&
!inst->is_partial_write()) {
last_mrf_move[inst->dst.reg] = inst;
}
}
if (progress)
live_intervals_valid = false;
return progress;
}
static void
clear_deps_for_inst_src(fs_inst *inst, int dispatch_width, bool *deps,
int first_grf, int grf_len)
{
bool inst_16wide = (dispatch_width > 8 &&
!inst->force_uncompressed &&
!inst->force_sechalf);
/* Clear the flag for registers that actually got read (as expected). */
for (int i = 0; i < 3; i++) {
int grf;
if (inst->src[i].file == GRF) {
grf = inst->src[i].reg;
} else if (inst->src[i].file == HW_REG &&
inst->src[i].fixed_hw_reg.file == BRW_GENERAL_REGISTER_FILE) {
grf = inst->src[i].fixed_hw_reg.nr;
} else {
continue;
}
if (grf >= first_grf &&
grf < first_grf + grf_len) {
deps[grf - first_grf] = false;
if (inst_16wide)
deps[grf - first_grf + 1] = false;
}
}
}
/**
* Implements this workaround for the original 965:
*
* "[DevBW, DevCL] Implementation Restrictions: As the hardware does not
* check for post destination dependencies on this instruction, software
* must ensure that there is no destination hazard for the case of ‘write
* followed by a posted write’ shown in the following example.
*
* 1. mov r3 0
* 2. send r3.xy <rest of send instruction>
* 3. mov r2 r3
*
* Due to no post-destination dependency check on the ‘send’, the above
* code sequence could have two instructions (1 and 2) in flight at the
* same time that both consider ‘r3’ as the target of their final writes.
*/
void
fs_visitor::insert_gen4_pre_send_dependency_workarounds(fs_inst *inst)
{
int reg_size = dispatch_width / 8;
int write_len = inst->regs_written * reg_size;
int first_write_grf = inst->dst.reg;
bool needs_dep[BRW_MAX_MRF];
assert(write_len < (int)sizeof(needs_dep) - 1);
memset(needs_dep, false, sizeof(needs_dep));
memset(needs_dep, true, write_len);
clear_deps_for_inst_src(inst, dispatch_width,
needs_dep, first_write_grf, write_len);
/* Walk backwards looking for writes to registers we're writing which
* aren't read since being written. If we hit the start of the program,
* we assume that there are no outstanding dependencies on entry to the
* program.
*/
for (fs_inst *scan_inst = (fs_inst *)inst->prev;
scan_inst != NULL;
scan_inst = (fs_inst *)scan_inst->prev) {
/* If we hit control flow, assume that there *are* outstanding
* dependencies, and force their cleanup before our instruction.
*/
if (scan_inst->is_control_flow()) {
for (int i = 0; i < write_len; i++) {
if (needs_dep[i]) {
inst->insert_before(DEP_RESOLVE_MOV(first_write_grf + i));
}
}
return;
}
bool scan_inst_16wide = (dispatch_width > 8 &&
!scan_inst->force_uncompressed &&
!scan_inst->force_sechalf);
/* We insert our reads as late as possible on the assumption that any
* instruction but a MOV that might have left us an outstanding
* dependency has more latency than a MOV.
*/
if (scan_inst->dst.file == GRF) {
for (int i = 0; i < scan_inst->regs_written; i++) {
int reg = scan_inst->dst.reg + i * reg_size;
if (reg >= first_write_grf &&
reg < first_write_grf + write_len &&
needs_dep[reg - first_write_grf]) {
inst->insert_before(DEP_RESOLVE_MOV(reg));
needs_dep[reg - first_write_grf] = false;
if (scan_inst_16wide)
needs_dep[reg - first_write_grf + 1] = false;
}
}
}
/* Clear the flag for registers that actually got read (as expected). */
clear_deps_for_inst_src(scan_inst, dispatch_width,
needs_dep, first_write_grf, write_len);
/* Continue the loop only if we haven't resolved all the dependencies */
int i;
for (i = 0; i < write_len; i++) {
if (needs_dep[i])
break;
}
if (i == write_len)
return;
}
}
/**
* Implements this workaround for the original 965:
*
* "[DevBW, DevCL] Errata: A destination register from a send can not be
* used as a destination register until after it has been sourced by an
* instruction with a different destination register.
*/
void
fs_visitor::insert_gen4_post_send_dependency_workarounds(fs_inst *inst)
{
int write_len = inst->regs_written * dispatch_width / 8;
int first_write_grf = inst->dst.reg;
bool needs_dep[BRW_MAX_MRF];
assert(write_len < (int)sizeof(needs_dep) - 1);
memset(needs_dep, false, sizeof(needs_dep));
memset(needs_dep, true, write_len);
/* Walk forwards looking for writes to registers we're writing which aren't
* read before being written.
*/
for (fs_inst *scan_inst = (fs_inst *)inst->next;
!scan_inst->is_tail_sentinel();
scan_inst = (fs_inst *)scan_inst->next) {
/* If we hit control flow, force resolve all remaining dependencies. */
if (scan_inst->is_control_flow()) {
for (int i = 0; i < write_len; i++) {
if (needs_dep[i])
scan_inst->insert_before(DEP_RESOLVE_MOV(first_write_grf + i));
}
return;
}
/* Clear the flag for registers that actually got read (as expected). */
clear_deps_for_inst_src(scan_inst, dispatch_width,
needs_dep, first_write_grf, write_len);
/* We insert our reads as late as possible since they're reading the
* result of a SEND, which has massive latency.
*/
if (scan_inst->dst.file == GRF &&
scan_inst->dst.reg >= first_write_grf &&
scan_inst->dst.reg < first_write_grf + write_len &&
needs_dep[scan_inst->dst.reg - first_write_grf]) {
scan_inst->insert_before(DEP_RESOLVE_MOV(scan_inst->dst.reg));
needs_dep[scan_inst->dst.reg - first_write_grf] = false;
}
/* Continue the loop only if we haven't resolved all the dependencies */
int i;
for (i = 0; i < write_len; i++) {
if (needs_dep[i])
break;
}
if (i == write_len)
return;
}
/* If we hit the end of the program, resolve all remaining dependencies out
* of paranoia.
*/
fs_inst *last_inst = (fs_inst *)this->instructions.get_tail();
assert(last_inst->eot);
for (int i = 0; i < write_len; i++) {
if (needs_dep[i])
last_inst->insert_before(DEP_RESOLVE_MOV(first_write_grf + i));
}
}
void
fs_visitor::insert_gen4_send_dependency_workarounds()
{
if (brw->gen != 4 || brw->is_g4x)
return;
/* Note that we're done with register allocation, so GRF fs_regs always
* have a .reg_offset of 0.
*/
foreach_list_safe(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
if (inst->mlen != 0 && inst->dst.file == GRF) {
insert_gen4_pre_send_dependency_workarounds(inst);
insert_gen4_post_send_dependency_workarounds(inst);
}
}
}
/**
* Turns the generic expression-style uniform pull constant load instruction
* into a hardware-specific series of instructions for loading a pull
* constant.
*
* The expression style allows the CSE pass before this to optimize out
* repeated loads from the same offset, and gives the pre-register-allocation
* scheduling full flexibility, while the conversion to native instructions
* allows the post-register-allocation scheduler the best information
* possible.
*
* Note that execution masking for setting up pull constant loads is special:
* the channels that need to be written are unrelated to the current execution
* mask, since a later instruction will use one of the result channels as a
* source operand for all 8 or 16 of its channels.
*/
void
fs_visitor::lower_uniform_pull_constant_loads()
{
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
if (inst->opcode != FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD)
continue;
if (brw->gen >= 7) {
/* The offset arg before was a vec4-aligned byte offset. We need to
* turn it into a dword offset.
*/
fs_reg const_offset_reg = inst->src[1];
assert(const_offset_reg.file == IMM &&
const_offset_reg.type == BRW_REGISTER_TYPE_UD);
const_offset_reg.imm.u /= 4;
fs_reg payload = fs_reg(this, glsl_type::uint_type);
/* This is actually going to be a MOV, but since only the first dword
* is accessed, we have a special opcode to do just that one. Note
* that this needs to be an operation that will be considered a def
* by live variable analysis, or register allocation will explode.
*/
fs_inst *setup = new(mem_ctx) fs_inst(FS_OPCODE_SET_SIMD4X2_OFFSET,
payload, const_offset_reg);
setup->force_writemask_all = true;
setup->ir = inst->ir;
setup->annotation = inst->annotation;
inst->insert_before(setup);
/* Similarly, this will only populate the first 4 channels of the
* result register (since we only use smear values from 0-3), but we
* don't tell the optimizer.
*/
inst->opcode = FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD_GEN7;
inst->src[1] = payload;
this->live_intervals_valid = false;
} else {
/* Before register allocation, we didn't tell the scheduler about the
* MRF we use. We know it's safe to use this MRF because nothing
* else does except for register spill/unspill, which generates and
* uses its MRF within a single IR instruction.
*/
inst->base_mrf = 14;
inst->mlen = 1;
}
}
}
void
fs_visitor::dump_instruction(backend_instruction *be_inst)
{
fs_inst *inst = (fs_inst *)be_inst;
if (inst->predicate) {
printf("(%cf0.%d) ",
inst->predicate_inverse ? '-' : '+',
inst->flag_subreg);
}
printf("%s", brw_instruction_name(inst->opcode));
if (inst->saturate)
printf(".sat");
if (inst->conditional_mod) {
printf(".cmod");
if (!inst->predicate &&
(brw->gen < 5 || (inst->opcode != BRW_OPCODE_SEL &&
inst->opcode != BRW_OPCODE_IF &&
inst->opcode != BRW_OPCODE_WHILE))) {
printf(".f0.%d\n", inst->flag_subreg);
}
}
printf(" ");
switch (inst->dst.file) {
case GRF:
printf("vgrf%d", inst->dst.reg);
if (inst->dst.reg_offset)
printf("+%d", inst->dst.reg_offset);
break;
case MRF:
printf("m%d", inst->dst.reg);
break;
case BAD_FILE:
printf("(null)");
break;
case UNIFORM:
printf("***u%d***", inst->dst.reg);
break;
default:
printf("???");
break;
}
printf(", ");
for (int i = 0; i < 3; i++) {
if (inst->src[i].negate)
printf("-");
if (inst->src[i].abs)
printf("|");
switch (inst->src[i].file) {
case GRF:
printf("vgrf%d", inst->src[i].reg);
if (inst->src[i].reg_offset)
printf("+%d", inst->src[i].reg_offset);
break;
case MRF:
printf("***m%d***", inst->src[i].reg);
break;
case UNIFORM:
printf("u%d", inst->src[i].reg);
if (inst->src[i].reg_offset)
printf(".%d", inst->src[i].reg_offset);
break;
case BAD_FILE:
printf("(null)");
break;
case IMM:
switch (inst->src[i].type) {
case BRW_REGISTER_TYPE_F:
printf("%ff", inst->src[i].imm.f);
break;
case BRW_REGISTER_TYPE_D:
printf("%dd", inst->src[i].imm.i);
break;
case BRW_REGISTER_TYPE_UD:
printf("%uu", inst->src[i].imm.u);
break;
default:
printf("???");
break;
}
break;
default:
printf("???");
break;
}
if (inst->src[i].abs)
printf("|");
if (i < 3)
printf(", ");
}
printf(" ");
if (inst->force_uncompressed)
printf("1sthalf ");
if (inst->force_sechalf)
printf("2ndhalf ");
printf("\n");
}
/**
* Possibly returns an instruction that set up @param reg.
*
* Sometimes we want to take the result of some expression/variable
* dereference tree and rewrite the instruction generating the result
* of the tree. When processing the tree, we know that the
* instructions generated are all writing temporaries that are dead
* outside of this tree. So, if we have some instructions that write
* a temporary, we're free to point that temp write somewhere else.
*
* Note that this doesn't guarantee that the instruction generated
* only reg -- it might be the size=4 destination of a texture instruction.
*/
fs_inst *
fs_visitor::get_instruction_generating_reg(fs_inst *start,
fs_inst *end,
fs_reg reg)
{
if (end == start ||
end->is_partial_write() ||
reg.reladdr ||
!reg.equals(end->dst)) {
return NULL;
} else {
return end;
}
}
void
fs_visitor::setup_payload_gen6()
{
bool uses_depth =
(fp->Base.InputsRead & (1 << VARYING_SLOT_POS)) != 0;
unsigned barycentric_interp_modes = c->prog_data.barycentric_interp_modes;
assert(brw->gen >= 6);
/* R0-1: masks, pixel X/Y coordinates. */
c->nr_payload_regs = 2;
/* R2: only for 32-pixel dispatch.*/
/* R3-26: barycentric interpolation coordinates. These appear in the
* same order that they appear in the brw_wm_barycentric_interp_mode
* enum. Each set of coordinates occupies 2 registers if dispatch width
* == 8 and 4 registers if dispatch width == 16. Coordinates only
* appear if they were enabled using the "Barycentric Interpolation
* Mode" bits in WM_STATE.
*/
for (int i = 0; i < BRW_WM_BARYCENTRIC_INTERP_MODE_COUNT; ++i) {
if (barycentric_interp_modes & (1 << i)) {
c->barycentric_coord_reg[i] = c->nr_payload_regs;
c->nr_payload_regs += 2;
if (dispatch_width == 16) {
c->nr_payload_regs += 2;
}
}
}
/* R27: interpolated depth if uses source depth */
if (uses_depth) {
c->source_depth_reg = c->nr_payload_regs;
c->nr_payload_regs++;
if (dispatch_width == 16) {
/* R28: interpolated depth if not 8-wide. */
c->nr_payload_regs++;
}
}
/* R29: interpolated W set if GEN6_WM_USES_SOURCE_W. */
if (uses_depth) {
c->source_w_reg = c->nr_payload_regs;
c->nr_payload_regs++;
if (dispatch_width == 16) {
/* R30: interpolated W if not 8-wide. */
c->nr_payload_regs++;
}
}
/* R31: MSAA position offsets. */
/* R32-: bary for 32-pixel. */
/* R58-59: interp W for 32-pixel. */
if (fp->Base.OutputsWritten & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) {
c->source_depth_to_render_target = true;
}
}
bool
fs_visitor::run()
{
sanity_param_count = fp->Base.Parameters->NumParameters;
uint32_t orig_nr_params = c->prog_data.nr_params;
if (brw->gen >= 6)
setup_payload_gen6();
else
setup_payload_gen4();
if (0) {
emit_dummy_fs();
} else {
if (INTEL_DEBUG & DEBUG_SHADER_TIME)
emit_shader_time_begin();
calculate_urb_setup();
if (brw->gen < 6)
emit_interpolation_setup_gen4();
else
emit_interpolation_setup_gen6();
/* We handle discards by keeping track of the still-live pixels in f0.1.
* Initialize it with the dispatched pixels.
*/
if (fp->UsesKill) {
fs_inst *discard_init = emit(FS_OPCODE_MOV_DISPATCH_TO_FLAGS);
discard_init->flag_subreg = 1;
}
/* Generate FS IR for main(). (the visitor only descends into
* functions called "main").
*/
if (shader) {
foreach_list(node, &*shader->ir) {
ir_instruction *ir = (ir_instruction *)node;
base_ir = ir;
this->result = reg_undef;
ir->accept(this);
}
} else {
emit_fragment_program_code();
}
base_ir = NULL;
if (failed)
return false;
emit(FS_OPCODE_PLACEHOLDER_HALT);
emit_fb_writes();
split_virtual_grfs();
move_uniform_array_access_to_pull_constants();
setup_pull_constants();
bool progress;
do {
progress = false;
compact_virtual_grfs();
progress = remove_duplicate_mrf_writes() || progress;
progress = opt_algebraic() || progress;
progress = opt_cse() || progress;
progress = opt_copy_propagate() || progress;
progress = dead_code_eliminate() || progress;
progress = dead_code_eliminate_local() || progress;
progress = register_coalesce() || progress;
progress = register_coalesce_2() || progress;
progress = compute_to_mrf() || progress;
} while (progress);
remove_dead_constants();
schedule_instructions(false);
lower_uniform_pull_constant_loads();
assign_curb_setup();
assign_urb_setup();
if (0) {
/* Debug of register spilling: Go spill everything. */
for (int i = 0; i < virtual_grf_count; i++) {
spill_reg(i);
}
}
if (0)
assign_regs_trivial();
else {
while (!assign_regs()) {
if (failed)
break;
}
}
}
assert(force_uncompressed_stack == 0);
assert(force_sechalf_stack == 0);
/* This must come after all optimization and register allocation, since
* it inserts dead code that happens to have side effects, and it does
* so based on the actual physical registers in use.
*/
insert_gen4_send_dependency_workarounds();
if (failed)
return false;
schedule_instructions(true);
if (dispatch_width == 8) {
c->prog_data.reg_blocks = brw_register_blocks(grf_used);
} else {
c->prog_data.reg_blocks_16 = brw_register_blocks(grf_used);
/* Make sure we didn't try to sneak in an extra uniform */
assert(orig_nr_params == c->prog_data.nr_params);
(void) orig_nr_params;
}
/* If any state parameters were appended, then ParameterValues could have
* been realloced, in which case the driver uniform storage set up by
* _mesa_associate_uniform_storage() would point to freed memory. Make
* sure that didn't happen.
*/
assert(sanity_param_count == fp->Base.Parameters->NumParameters);
return !failed;
}
const unsigned *
brw_wm_fs_emit(struct brw_context *brw, struct brw_wm_compile *c,
struct gl_fragment_program *fp,
struct gl_shader_program *prog,
unsigned *final_assembly_size)
{
bool start_busy = false;
float start_time = 0;
if (unlikely(brw->perf_debug)) {
start_busy = (brw->batch.last_bo &&
drm_intel_bo_busy(brw->batch.last_bo));
start_time = get_time();
}
struct brw_shader *shader = NULL;
if (prog)
shader = (brw_shader *) prog->_LinkedShaders[MESA_SHADER_FRAGMENT];
if (unlikely(INTEL_DEBUG & DEBUG_WM)) {
if (prog) {
printf("GLSL IR for native fragment shader %d:\n", prog->Name);
_mesa_print_ir(shader->ir, NULL);
printf("\n\n");
} else {
printf("ARB_fragment_program %d ir for native fragment shader\n",
fp->Base.Id);
_mesa_print_program(&fp->Base);
}
}
/* Now the main event: Visit the shader IR and generate our FS IR for it.
*/
fs_visitor v(brw, c, prog, fp, 8);
if (!v.run()) {
if (prog) {
prog->LinkStatus = false;
ralloc_strcat(&prog->InfoLog, v.fail_msg);
}
_mesa_problem(NULL, "Failed to compile fragment shader: %s\n",
v.fail_msg);
return NULL;
}
exec_list *simd16_instructions = NULL;
fs_visitor v2(brw, c, prog, fp, 16);
bool no16 = INTEL_DEBUG & DEBUG_NO16;
if (brw->gen >= 5 && c->prog_data.nr_pull_params == 0 && likely(!no16)) {
v2.import_uniforms(&v);
if (!v2.run()) {
perf_debug("16-wide shader failed to compile, falling back to "
"8-wide at a 10-20%% performance cost: %s", v2.fail_msg);
} else {
simd16_instructions = &v2.instructions;
}
}
c->prog_data.dispatch_width = 8;
fs_generator g(brw, c, prog, fp, v.dual_src_output.file != BAD_FILE);
const unsigned *generated = g.generate_assembly(&v.instructions,
simd16_instructions,
final_assembly_size);
if (unlikely(brw->perf_debug) && shader) {
if (shader->compiled_once)
brw_wm_debug_recompile(brw, prog, &c->key);
shader->compiled_once = true;
if (start_busy && !drm_intel_bo_busy(brw->batch.last_bo)) {
perf_debug("FS compile took %.03f ms and stalled the GPU\n",
(get_time() - start_time) * 1000);
}
}
return generated;
}
bool
brw_fs_precompile(struct gl_context *ctx, struct gl_shader_program *prog)
{
struct brw_context *brw = brw_context(ctx);
struct brw_wm_prog_key key;
if (!prog->_LinkedShaders[MESA_SHADER_FRAGMENT])
return true;
struct gl_fragment_program *fp = (struct gl_fragment_program *)
prog->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program;
struct brw_fragment_program *bfp = brw_fragment_program(fp);
bool program_uses_dfdy = fp->UsesDFdy;
memset(&key, 0, sizeof(key));
if (brw->gen < 6) {
if (fp->UsesKill)
key.iz_lookup |= IZ_PS_KILL_ALPHATEST_BIT;
if (fp->Base.OutputsWritten & BITFIELD64_BIT(FRAG_RESULT_DEPTH))
key.iz_lookup |= IZ_PS_COMPUTES_DEPTH_BIT;
/* Just assume depth testing. */
key.iz_lookup |= IZ_DEPTH_TEST_ENABLE_BIT;
key.iz_lookup |= IZ_DEPTH_WRITE_ENABLE_BIT;
}
if (brw->gen < 6)
key.input_slots_valid |= BITFIELD64_BIT(VARYING_SLOT_POS);
for (int i = 0; i < VARYING_SLOT_MAX; i++) {
if (!(fp->Base.InputsRead & BITFIELD64_BIT(i)))
continue;
if (brw->gen < 6) {
if (_mesa_varying_slot_in_fs((gl_varying_slot) i))
key.input_slots_valid |= BITFIELD64_BIT(i);
}
}
key.clamp_fragment_color = ctx->API == API_OPENGL_COMPAT;
for (int i = 0; i < MAX_SAMPLERS; i++) {
if (fp->Base.ShadowSamplers & (1 << i)) {
/* Assume DEPTH_TEXTURE_MODE is the default: X, X, X, 1 */
key.tex.swizzles[i] =
MAKE_SWIZZLE4(SWIZZLE_X, SWIZZLE_X, SWIZZLE_X, SWIZZLE_ONE);
} else {
/* Color sampler: assume no swizzling. */
key.tex.swizzles[i] = SWIZZLE_XYZW;
}
}
if (fp->Base.InputsRead & VARYING_BIT_POS) {
key.drawable_height = ctx->DrawBuffer->Height;
}
if ((fp->Base.InputsRead & VARYING_BIT_POS) || program_uses_dfdy) {
key.render_to_fbo = _mesa_is_user_fbo(ctx->DrawBuffer);
}
key.nr_color_regions = 1;
key.program_string_id = bfp->id;
uint32_t old_prog_offset = brw->wm.prog_offset;
struct brw_wm_prog_data *old_prog_data = brw->wm.prog_data;
bool success = do_wm_prog(brw, prog, bfp, &key);
brw->wm.prog_offset = old_prog_offset;
brw->wm.prog_data = old_prog_data;
return success;
}