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gerrit-public.fairphone.software / platform / external / mesa3d / 40492be2a4a339b02c38990ad8736644f3a8776b / . / src / mesa / drivers / dri / i965 / brw_fs.cpp
blob: 983e8db63e0e1a4cea520f476feeba9c65d4608c [file] [log] [blame]
/*
* 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 "util/hash_table.h"
#include "main/macros.h"
#include "main/shaderobj.h"
#include "main/fbobject.h"
#include "program/prog_parameter.h"
#include "program/prog_print.h"
#include "util/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 "brw_cfg.h"
#include "brw_dead_control_flow.h"
#include "main/uniforms.h"
#include "brw_fs_live_variables.h"
#include "glsl/glsl_types.h"
void
fs_inst::init(enum opcode opcode, uint8_t exec_size, const fs_reg &dst,
fs_reg *src, int sources)
{
memset(this, 0, sizeof(*this));
this->opcode = opcode;
this->dst = dst;
this->src = src;
this->sources = sources;
this->exec_size = exec_size;
assert(dst.file != IMM && dst.file != UNIFORM);
/* If exec_size == 0, try to guess it from the registers. Since all
* manner of things may use hardware registers, we first try to guess
* based on GRF registers. If this fails, we will go ahead and take the
* width from the destination register.
*/
if (this->exec_size == 0) {
if (dst.file == GRF) {
this->exec_size = dst.width;
} else {
for (int i = 0; i < sources; ++i) {
if (src[i].file != GRF)
continue;
if (this->exec_size <= 1)
this->exec_size = src[i].width;
assert(src[i].width == 1 || src[i].width == this->exec_size);
}
}
if (this->exec_size == 0 && dst.file != BAD_FILE)
this->exec_size = dst.width;
}
assert(this->exec_size != 0);
for (int i = 0; i < sources; ++i) {
switch (this->src[i].file) {
case BAD_FILE:
this->src[i].effective_width = 8;
break;
case GRF:
case HW_REG:
assert(this->src[i].width > 0);
if (this->src[i].width == 1) {
this->src[i].effective_width = this->exec_size;
} else {
this->src[i].effective_width = this->src[i].width;
}
break;
case IMM:
case UNIFORM:
this->src[i].effective_width = this->exec_size;
break;
default:
unreachable("Invalid source register file");
}
}
this->dst.effective_width = this->exec_size;
this->conditional_mod = BRW_CONDITIONAL_NONE;
/* This will be the case for almost all instructions. */
switch (dst.file) {
case GRF:
case HW_REG:
case MRF:
this->regs_written = (dst.width * dst.stride * type_sz(dst.type) + 31) / 32;
break;
case BAD_FILE:
this->regs_written = 0;
break;
case IMM:
case UNIFORM:
unreachable("Invalid destination register file");
default:
unreachable("Invalid register file");
}
this->writes_accumulator = false;
}
fs_inst::fs_inst()
{
fs_reg *src = ralloc_array(this, fs_reg, 3);
init(BRW_OPCODE_NOP, 8, dst, src, 0);
}
fs_inst::fs_inst(enum opcode opcode, uint8_t exec_size)
{
fs_reg *src = ralloc_array(this, fs_reg, 3);
init(opcode, exec_size, reg_undef, src, 0);
}
fs_inst::fs_inst(enum opcode opcode, const fs_reg &dst)
{
fs_reg *src = ralloc_array(this, fs_reg, 3);
init(opcode, 0, dst, src, 0);
}
fs_inst::fs_inst(enum opcode opcode, uint8_t exec_size, const fs_reg &dst,
const fs_reg &src0)
{
fs_reg *src = ralloc_array(this, fs_reg, 3);
src[0] = src0;
init(opcode, exec_size, dst, src, 1);
}
fs_inst::fs_inst(enum opcode opcode, const fs_reg &dst, const fs_reg &src0)
{
fs_reg *src = ralloc_array(this, fs_reg, 3);
src[0] = src0;
init(opcode, 0, dst, src, 1);
}
fs_inst::fs_inst(enum opcode opcode, uint8_t exec_size, const fs_reg &dst,
const fs_reg &src0, const fs_reg &src1)
{
fs_reg *src = ralloc_array(this, fs_reg, 3);
src[0] = src0;
src[1] = src1;
init(opcode, exec_size, dst, src, 2);
}
fs_inst::fs_inst(enum opcode opcode, const fs_reg &dst, const fs_reg &src0,
const fs_reg &src1)
{
fs_reg *src = ralloc_array(this, fs_reg, 3);
src[0] = src0;
src[1] = src1;
init(opcode, 0, dst, src, 2);
}
fs_inst::fs_inst(enum opcode opcode, uint8_t exec_size, const fs_reg &dst,
const fs_reg &src0, const fs_reg &src1, const fs_reg &src2)
{
fs_reg *src = ralloc_array(this, fs_reg, 3);
src[0] = src0;
src[1] = src1;
src[2] = src2;
init(opcode, exec_size, dst, src, 3);
}
fs_inst::fs_inst(enum opcode opcode, const fs_reg &dst, const fs_reg &src0,
const fs_reg &src1, const fs_reg &src2)
{
fs_reg *src = ralloc_array(this, fs_reg, 3);
src[0] = src0;
src[1] = src1;
src[2] = src2;
init(opcode, 0, dst, src, 3);
}
fs_inst::fs_inst(enum opcode opcode, const fs_reg &dst, fs_reg src[], int sources)
{
init(opcode, 0, dst, src, sources);
}
fs_inst::fs_inst(enum opcode opcode, uint8_t exec_width, const fs_reg &dst,
fs_reg src[], int sources)
{
init(opcode, exec_width, dst, src, sources);
}
fs_inst::fs_inst(const fs_inst &that)
{
memcpy(this, &that, sizeof(that));
this->src = ralloc_array(this, fs_reg, that.sources);
for (int i = 0; i < that.sources; i++)
this->src[i] = that.src[i];
}
void
fs_inst::resize_sources(uint8_t num_sources)
{
if (this->sources != num_sources) {
this->src = reralloc(this, this->src, fs_reg, num_sources);
this->sources = num_sources;
}
}
#define ALU1(op) \
fs_inst * \
fs_visitor::op(const fs_reg &dst, const fs_reg &src0) \
{ \
return new(mem_ctx) fs_inst(BRW_OPCODE_##op, dst, src0); \
}
#define ALU2(op) \
fs_inst * \
fs_visitor::op(const fs_reg &dst, const fs_reg &src0, \
const fs_reg &src1) \
{ \
return new(mem_ctx) fs_inst(BRW_OPCODE_##op, dst, src0, src1); \
}
#define ALU2_ACC(op) \
fs_inst * \
fs_visitor::op(const fs_reg &dst, const fs_reg &src0, \
const fs_reg &src1) \
{ \
fs_inst *inst = new(mem_ctx) fs_inst(BRW_OPCODE_##op, dst, src0, src1);\
inst->writes_accumulator = true; \
return inst; \
}
#define ALU3(op) \
fs_inst * \
fs_visitor::op(const fs_reg &dst, const fs_reg &src0, \
const fs_reg &src1, const 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_ACC(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)
ALU3(MAD)
ALU2_ACC(ADDC)
ALU2_ACC(SUBB)
ALU2(SEL)
ALU2(MAC)
/** Gen4 predicated IF. */
fs_inst *
fs_visitor::IF(enum brw_predicate predicate)
{
fs_inst *inst = new(mem_ctx) fs_inst(BRW_OPCODE_IF, dispatch_width);
inst->predicate = predicate;
return inst;
}
/** Gen6 IF with embedded comparison. */
fs_inst *
fs_visitor::IF(const fs_reg &src0, const fs_reg &src1,
enum brw_conditional_mod condition)
{
assert(brw->gen == 6);
fs_inst *inst = new(mem_ctx) fs_inst(BRW_OPCODE_IF, dispatch_width,
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,
enum brw_conditional_mod 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;
}
fs_inst *
fs_visitor::LOAD_PAYLOAD(const fs_reg &dst, fs_reg *src, int sources)
{
uint8_t exec_size = dst.width;
for (int i = 0; i < sources; ++i) {
assert(src[i].width % dst.width == 0);
if (src[i].width > exec_size)
exec_size = src[i].width;
}
fs_inst *inst = new(mem_ctx) fs_inst(SHADER_OPCODE_LOAD_PAYLOAD, exec_size,
dst, src, sources);
inst->regs_written = 0;
for (int i = 0; i < sources; ++i) {
/* The LOAD_PAYLOAD instruction only really makes sense if we are
* dealing with whole registers. If this ever changes, we can deal
* with it later.
*/
int size = src[i].effective_width * type_sz(src[i].type);
assert(size % 32 == 0);
inst->regs_written += (size + 31) / 32;
}
return inst;
}
exec_list
fs_visitor::VARYING_PULL_CONSTANT_LOAD(const fs_reg &dst,
const fs_reg &surf_index,
const 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, fs_reg(const_offset & ~3)));
int scale = 1;
if (brw->gen == 4 && dst.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;
assert(dst.width % 8 == 0);
int regs_written = 4 * (dst.width / 8) * scale;
fs_reg vec4_result = fs_reg(GRF, virtual_grf_alloc(regs_written),
dst.type, dst.width);
inst = new(mem_ctx) fs_inst(op, vec4_result, surf_index, vec4_offset);
inst->regs_written = regs_written;
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;
}
fs_reg result = offset(vec4_result, (const_offset & 3) * scale);
instructions.push_tail(MOV(dst, 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->exec_size = 8;
return inst;
}
bool
fs_inst::equals(fs_inst *inst) const
{
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 &&
target == inst->target &&
eot == inst->eot &&
header_present == inst->header_present &&
shadow_compare == inst->shadow_compare &&
exec_size == inst->exec_size &&
offset == inst->offset);
}
bool
fs_inst::overwrites_reg(const fs_reg &reg) const
{
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() const
{
switch (opcode) {
case FS_OPCODE_VARYING_PULL_CONSTANT_LOAD_GEN7:
case SHADER_OPCODE_SHADER_TIME_ADD:
case FS_OPCODE_INTERPOLATE_AT_CENTROID:
case FS_OPCODE_INTERPOLATE_AT_SAMPLE:
case FS_OPCODE_INTERPOLATE_AT_SHARED_OFFSET:
case FS_OPCODE_INTERPOLATE_AT_PER_SLOT_OFFSET:
case SHADER_OPCODE_UNTYPED_ATOMIC:
case SHADER_OPCODE_UNTYPED_SURFACE_READ:
return true;
case FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD:
return src[1].file == GRF;
case FS_OPCODE_FB_WRITE:
return src[0].file == GRF;
default:
if (is_tex())
return src[0].file == GRF;
return false;
}
}
bool
fs_inst::can_do_source_mods(struct brw_context *brw)
{
if (brw->gen == 6 && is_math())
return false;
if (is_send_from_grf())
return false;
if (!backend_instruction::can_do_source_mods())
return false;
return true;
}
void
fs_reg::init()
{
memset(this, 0, sizeof(*this));
stride = 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->fixed_hw_reg.dw1.f = f;
this->width = 1;
}
/** Immediate value constructor. */
fs_reg::fs_reg(int32_t i)
{
init();
this->file = IMM;
this->type = BRW_REGISTER_TYPE_D;
this->fixed_hw_reg.dw1.d = i;
this->width = 1;
}
/** Immediate value constructor. */
fs_reg::fs_reg(uint32_t u)
{
init();
this->file = IMM;
this->type = BRW_REGISTER_TYPE_UD;
this->fixed_hw_reg.dw1.ud = u;
this->width = 1;
}
/** Fixed brw_reg. */
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;
this->width = 1 << fixed_hw_reg.width;
}
bool
fs_reg::equals(const fs_reg &r) const
{
return (file == r.file &&
reg == r.reg &&
reg_offset == r.reg_offset &&
subreg_offset == r.subreg_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 &&
width == r.width &&
stride == r.stride);
}
fs_reg &
fs_reg::apply_stride(unsigned stride)
{
assert((this->stride * stride) <= 4 &&
(is_power_of_two(stride) || stride == 0) &&
file != HW_REG && file != IMM);
this->stride *= stride;
return *this;
}
fs_reg &
fs_reg::set_smear(unsigned subreg)
{
assert(file != HW_REG && file != IMM);
subreg_offset = subreg * type_sz(type);
stride = 0;
return *this;
}
bool
fs_reg::is_contiguous() const
{
return stride == 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_ATOMIC_UINT:
return 0;
case GLSL_TYPE_IMAGE:
case GLSL_TYPE_VOID:
case GLSL_TYPE_ERROR:
case GLSL_TYPE_INTERFACE:
unreachable("not reached");
}
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->exec_size = 8;
/* 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.set_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.set_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, prog, 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(new(mem_ctx) fs_inst(SHADER_OPCODE_SHADER_TIME_ADD,
fs_reg(), payload, offset, value));
}
void
fs_visitor::vfail(const char *format, va_list va)
{
char *msg;
if (failed)
return;
failed = true;
msg = ralloc_vasprintf(mem_ctx, format, 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);
}
}
void
fs_visitor::fail(const char *format, ...)
{
va_list va;
va_start(va, format);
vfail(format, va);
va_end(va);
}
/**
* Mark this program as impossible to compile in SIMD16 mode.
*
* During the SIMD8 compile (which happens first), we can detect and flag
* things that are unsupported in SIMD16 mode, so the compiler can skip
* the SIMD16 compile altogether.
*
* During a SIMD16 compile (if one happens anyway), this just calls fail().
*/
void
fs_visitor::no16(const char *format, ...)
{
va_list va;
va_start(va, format);
if (dispatch_width == 16) {
vfail(format, va);
} else {
simd16_unsupported = true;
if (brw->perf_debug) {
if (no16_msg)
ralloc_vasprintf_append(&no16_msg, format, va);
else
no16_msg = ralloc_vasprintf(mem_ctx, format, va);
}
}
va_end(va);
}
fs_inst *
fs_visitor::emit(enum opcode opcode)
{
return emit(new(mem_ctx) fs_inst(opcode, dispatch_width));
}
fs_inst *
fs_visitor::emit(enum opcode opcode, const fs_reg &dst)
{
return emit(new(mem_ctx) fs_inst(opcode, dst));
}
fs_inst *
fs_visitor::emit(enum opcode opcode, const fs_reg &dst, const fs_reg &src0)
{
return emit(new(mem_ctx) fs_inst(opcode, dst, src0));
}
fs_inst *
fs_visitor::emit(enum opcode opcode, const fs_reg &dst, const fs_reg &src0,
const fs_reg &src1)
{
return emit(new(mem_ctx) fs_inst(opcode, dst, src0, src1));
}
fs_inst *
fs_visitor::emit(enum opcode opcode, const fs_reg &dst, const fs_reg &src0,
const fs_reg &src1, const fs_reg &src2)
{
return emit(new(mem_ctx) fs_inst(opcode, dst, src0, src1, src2));
}
fs_inst *
fs_visitor::emit(enum opcode opcode, const fs_reg &dst,
fs_reg src[], int sources)
{
return emit(new(mem_ctx) fs_inst(opcode, dst, src, sources));
}
void
fs_visitor::push_force_uncompressed()
{
force_uncompressed_stack++;
}
void
fs_visitor::pop_force_uncompressed()
{
force_uncompressed_stack--;
assert(force_uncompressed_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() const
{
return ((this->predicate && this->opcode != BRW_OPCODE_SEL) ||
(this->dst.width * type_sz(this->dst.type)) < 32 ||
!this->dst.is_contiguous());
}
int
fs_inst::regs_read(fs_visitor *v, int arg) const
{
if (is_tex() && arg == 0 && src[0].file == GRF) {
return mlen;
} else if (opcode == FS_OPCODE_FB_WRITE && arg == 0) {
return mlen;
} else if (opcode == SHADER_OPCODE_UNTYPED_ATOMIC && arg == 0) {
return mlen;
} else if (opcode == SHADER_OPCODE_UNTYPED_SURFACE_READ && arg == 0) {
return mlen;
}
switch (src[arg].file) {
case BAD_FILE:
case UNIFORM:
case IMM:
return 1;
case GRF:
case HW_REG:
if (src[arg].stride == 0) {
return 1;
} else {
int size = src[arg].width * src[arg].stride * type_sz(src[arg].type);
return (size + 31) / 32;
}
case MRF:
unreachable("MRF registers are not allowed as sources");
default:
unreachable("Invalid register file");
}
}
bool
fs_inst::reads_flag() const
{
return predicate;
}
bool
fs_inst::writes_flag() const
{
return (conditional_mod && opcode != BRW_OPCODE_SEL) ||
opcode == FS_OPCODE_MOV_DISPATCH_TO_FLAGS;
}
/**
* 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;
if (inst->base_mrf == -1)
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_CMS:
case SHADER_OPCODE_TXF_MCS:
case SHADER_OPCODE_TG4:
case SHADER_OPCODE_TG4_OFFSET:
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 SHADER_OPCODE_GEN4_SCRATCH_READ:
return 1;
case FS_OPCODE_VARYING_PULL_CONSTANT_LOAD:
return inst->mlen;
case SHADER_OPCODE_GEN4_SCRATCH_WRITE:
return 2;
case SHADER_OPCODE_UNTYPED_ATOMIC:
case SHADER_OPCODE_UNTYPED_SURFACE_READ:
case FS_OPCODE_INTERPOLATE_AT_CENTROID:
case FS_OPCODE_INTERPOLATE_AT_SAMPLE:
case FS_OPCODE_INTERPOLATE_AT_SHARED_OFFSET:
case FS_OPCODE_INTERPOLATE_AT_PER_SLOT_OFFSET:
return 0;
default:
unreachable("not reached");
}
}
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;
switch (file) {
case UNIFORM:
this->width = 1;
break;
default:
this->width = 8;
}
}
/** Fixed HW reg constructor. */
fs_reg::fs_reg(enum register_file file, int reg, enum brw_reg_type type)
{
init();
this->file = file;
this->reg = reg;
this->type = type;
switch (file) {
case UNIFORM:
this->width = 1;
break;
default:
this->width = 8;
}
}
/** Fixed HW reg constructor. */
fs_reg::fs_reg(enum register_file file, int reg, enum brw_reg_type type,
uint8_t width)
{
init();
this->file = file;
this->reg = reg;
this->type = type;
this->width = width;
}
/** Automatic reg constructor. */
fs_reg::fs_reg(fs_visitor *v, const struct glsl_type *type)
{
init();
int reg_width = v->dispatch_width / 8;
this->file = GRF;
this->reg = v->virtual_grf_alloc(v->type_size(type) * reg_width);
this->reg_offset = 0;
this->type = brw_type_for_base_type(type);
this->width = v->dispatch_width;
assert(this->width == 8 || this->width == 16);
}
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 SIMD16, we need to follow from the uniform setup of SIMD8 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->push_constant_loc = v->push_constant_loc;
this->pull_constant_loc = v->pull_constant_loc;
this->uniforms = v->uniforms;
this->param_size = v->param_size;
}
/* 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 = uniforms;
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++) {
stage_prog_data->param[uniforms++] = &storage->storage[i];
}
}
/* Make sure we actually initialized the right amount of stuff here. */
assert(params_before + ir->type->component_slots() == uniforms);
(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->get_state_slots();
assert(slots != NULL);
for (unsigned int i = 0; i < ir->get_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->prog->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;
stage_prog_data->param[uniforms++] =
&prog->Parameters->ParameterValues[index][swiz];
}
}
}
fs_reg *
fs_visitor::emit_fragcoord_interpolation(ir_variable *ir)
{
assert(stage == MESA_SHADER_FRAGMENT);
brw_wm_prog_key *key = (brw_wm_prog_key*) this->key;
fs_reg *reg = new(this->mem_ctx) fs_reg(this, ir->type);
fs_reg wpos = *reg;
bool flip = !ir->data.origin_upper_left ^ key->render_to_fbo;
/* gl_FragCoord.x */
if (ir->data.pixel_center_integer) {
emit(MOV(wpos, this->pixel_x));
} else {
emit(ADD(wpos, this->pixel_x, fs_reg(0.5f)));
}
wpos = offset(wpos, 1);
/* gl_FragCoord.y */
if (!flip && ir->data.pixel_center_integer) {
emit(MOV(wpos, this->pixel_y));
} else {
fs_reg pixel_y = this->pixel_y;
float offset = (ir->data.pixel_center_integer ? 0.0 : 0.5);
if (flip) {
pixel_y.negate = true;
offset += key->drawable_height - 1.0;
}
emit(ADD(wpos, pixel_y, fs_reg(offset)));
}
wpos = offset(wpos, 1);
/* gl_FragCoord.z */
if (brw->gen >= 6) {
emit(MOV(wpos, fs_reg(brw_vec8_grf(payload.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 = offset(wpos, 1);
/* 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, bool is_sample)
{
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 (is_sample) {
if (interpolation_mode == INTERP_QUALIFIER_SMOOTH)
barycoord_mode = BRW_WM_PERSPECTIVE_SAMPLE_BARYCENTRIC;
else
barycoord_mode = BRW_WM_NONPERSPECTIVE_SAMPLE_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;
assert(stage == MESA_SHADER_FRAGMENT);
brw_wm_prog_data *prog_data = (brw_wm_prog_data*) this->prog_data;
brw_wm_prog_key *key = (brw_wm_prog_key*) this->key;
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(key->flat_shade);
int location = ir->data.location;
for (unsigned int i = 0; i < array_elements; i++) {
for (unsigned int j = 0; j < type->matrix_columns; j++) {
if (prog_data->urb_setup[location] == -1) {
/* If there's no incoming setup data for this slot, don't
* emit interpolation for it.
*/
attr = offset(attr, 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 = offset(attr, 1);
}
} else {
/* Smooth/noperspective interpolation case. */
for (unsigned int k = 0; k < type->vector_elements; k++) {
struct brw_reg interp = interp_reg(location, k);
if (brw->needs_unlit_centroid_workaround && ir->data.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;
inst = emit_linterp(attr, fs_reg(interp), interpolation_mode,
false, false);
inst->predicate = BRW_PREDICATE_NORMAL;
inst->predicate_inverse = true;
if (brw->has_pln)
inst->no_dd_clear = true;
inst = emit_linterp(attr, fs_reg(interp), interpolation_mode,
ir->data.centroid && !key->persample_shading,
ir->data.sample || key->persample_shading);
inst->predicate = BRW_PREDICATE_NORMAL;
inst->predicate_inverse = false;
if (brw->has_pln)
inst->no_dd_check = true;
} else {
emit_linterp(attr, fs_reg(interp), interpolation_mode,
ir->data.centroid && !key->persample_shading,
ir->data.sample || key->persample_shading);
}
if (brw->gen < 6 && interpolation_mode == INTERP_QUALIFIER_SMOOTH) {
emit(BRW_OPCODE_MUL, attr, attr, this->pixel_w);
}
attr = offset(attr, 1);
}
}
location++;
}
}
return reg;
}
fs_reg *
fs_visitor::emit_frontfacing_interpolation()
{
fs_reg *reg = new(this->mem_ctx) fs_reg(this, glsl_type::bool_type);
if (brw->gen >= 6) {
/* Bit 15 of g0.0 is 0 if the polygon is front facing. We want to create
* a boolean result from this (~0/true or 0/false).
*
* We can use the fact that bit 15 is the MSB of g0.0:W to accomplish
* this task in only one instruction:
* - a negation source modifier will flip the bit; and
* - a W -> D type conversion will sign extend the bit into the high
* word of the destination.
*
* An ASR 15 fills the low word of the destination.
*/
fs_reg g0 = fs_reg(retype(brw_vec1_grf(0, 0), BRW_REGISTER_TYPE_W));
g0.negate = true;
emit(ASR(*reg, g0, fs_reg(15)));
} else {
/* Bit 31 of g1.6 is 0 if the polygon is front facing. We want to create
* a boolean result from this (1/true or 0/false).
*
* Like in the above case, since the bit is the MSB of g1.6:UD we can use
* the negation source modifier to flip it. Unfortunately the SHR
* instruction only operates on UD (or D with an abs source modifier)
* sources without negation.
*
* Instead, use ASR (which will give ~0/true or 0/false) followed by an
* AND 1.
*/
fs_reg asr = fs_reg(this, glsl_type::bool_type);
fs_reg g1_6 = fs_reg(retype(brw_vec1_grf(1, 6), BRW_REGISTER_TYPE_D));
g1_6.negate = true;
emit(ASR(asr, g1_6, fs_reg(31)));
emit(AND(*reg, asr, fs_reg(1)));
}
return reg;
}
void
fs_visitor::compute_sample_position(fs_reg dst, fs_reg int_sample_pos)
{
assert(stage == MESA_SHADER_FRAGMENT);
brw_wm_prog_key *key = (brw_wm_prog_key*) this->key;
assert(dst.type == BRW_REGISTER_TYPE_F);
if (key->compute_pos_offset) {
/* Convert int_sample_pos to floating point */
emit(MOV(dst, int_sample_pos));
/* Scale to the range [0, 1] */
emit(MUL(dst, dst, fs_reg(1 / 16.0f)));
}
else {
/* From ARB_sample_shading specification:
* "When rendering to a non-multisample buffer, or if multisample
* rasterization is disabled, gl_SamplePosition will always be
* (0.5, 0.5).
*/
emit(MOV(dst, fs_reg(0.5f)));
}
}
fs_reg *
fs_visitor::emit_samplepos_setup()
{
assert(brw->gen >= 6);
this->current_annotation = "compute sample position";
fs_reg *reg = new(this->mem_ctx) fs_reg(this, glsl_type::vec2_type);
fs_reg pos = *reg;
fs_reg int_sample_x = fs_reg(this, glsl_type::int_type);
fs_reg int_sample_y = fs_reg(this, glsl_type::int_type);
/* WM will be run in MSDISPMODE_PERSAMPLE. So, only one of SIMD8 or SIMD16
* mode will be enabled.
*
* From the Ivy Bridge PRM, volume 2 part 1, page 344:
* R31.1:0 Position Offset X/Y for Slot[3:0]
* R31.3:2 Position Offset X/Y for Slot[7:4]
* .....
*
* The X, Y sample positions come in as bytes in thread payload. So, read
* the positions using vstride=16, width=8, hstride=2.
*/
struct brw_reg sample_pos_reg =
stride(retype(brw_vec1_grf(payload.sample_pos_reg, 0),
BRW_REGISTER_TYPE_B), 16, 8, 2);
if (dispatch_width == 8) {
emit(MOV(int_sample_x, fs_reg(sample_pos_reg)));
} else {
emit(MOV(half(int_sample_x, 0), fs_reg(sample_pos_reg)));
emit(MOV(half(int_sample_x, 1), fs_reg(suboffset(sample_pos_reg, 16))))
->force_sechalf = true;
}
/* Compute gl_SamplePosition.x */
compute_sample_position(pos, int_sample_x);
pos = offset(pos, 1);
if (dispatch_width == 8) {
emit(MOV(int_sample_y, fs_reg(suboffset(sample_pos_reg, 1))));
} else {
emit(MOV(half(int_sample_y, 0),
fs_reg(suboffset(sample_pos_reg, 1))));
emit(MOV(half(int_sample_y, 1), fs_reg(suboffset(sample_pos_reg, 17))))
->force_sechalf = true;
}
/* Compute gl_SamplePosition.y */
compute_sample_position(pos, int_sample_y);
return reg;
}
fs_reg *
fs_visitor::emit_sampleid_setup()
{
assert(stage == MESA_SHADER_FRAGMENT);
brw_wm_prog_key *key = (brw_wm_prog_key*) this->key;
assert(brw->gen >= 6);
this->current_annotation = "compute sample id";
fs_reg *reg = new(this->mem_ctx) fs_reg(this, glsl_type::int_type);
if (key->compute_sample_id) {
fs_reg t1 = fs_reg(this, glsl_type::int_type);
fs_reg t2 = fs_reg(this, glsl_type::int_type);
t2.type = BRW_REGISTER_TYPE_UW;
/* The PS will be run in MSDISPMODE_PERSAMPLE. For example with
* 8x multisampling, subspan 0 will represent sample N (where N
* is 0, 2, 4 or 6), subspan 1 will represent sample 1, 3, 5 or
* 7. We can find the value of N by looking at R0.0 bits 7:6
* ("Starting Sample Pair Index (SSPI)") and multiplying by two
* (since samples are always delivered in pairs). That is, we
* compute 2*((R0.0 & 0xc0) >> 6) == (R0.0 & 0xc0) >> 5. Then
* we need to add N to the sequence (0, 0, 0, 0, 1, 1, 1, 1) in
* case of SIMD8 and sequence (0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2,
* 2, 3, 3, 3, 3) in case of SIMD16. We compute this sequence by
* populating a temporary variable with the sequence (0, 1, 2, 3),
* and then reading from it using vstride=1, width=4, hstride=0.
* These computations hold good for 4x multisampling as well.
*
* For 2x MSAA and SIMD16, we want to use the sequence (0, 1, 0, 1):
* the first four slots are sample 0 of subspan 0; the next four
* are sample 1 of subspan 0; the third group is sample 0 of
* subspan 1, and finally sample 1 of subspan 1.
*/
fs_inst *inst;
inst = emit(BRW_OPCODE_AND, t1,
fs_reg(retype(brw_vec1_grf(0, 0), BRW_REGISTER_TYPE_UD)),
fs_reg(0xc0));
inst->force_writemask_all = true;
inst = emit(BRW_OPCODE_SHR, t1, t1, fs_reg(5));
inst->force_writemask_all = true;
/* This works for both SIMD8 and SIMD16 */
inst = emit(MOV(t2, brw_imm_v(key->persample_2x ? 0x1010 : 0x3210)));
inst->force_writemask_all = true;
/* This special instruction takes care of setting vstride=1,
* width=4, hstride=0 of t2 during an ADD instruction.
*/
emit(FS_OPCODE_SET_SAMPLE_ID, *reg, t1, t2);
} else {
/* As per GL_ARB_sample_shading specification:
* "When rendering to a non-multisample buffer, or if multisample
* rasterization is disabled, gl_SampleID will always be zero."
*/
emit(BRW_OPCODE_MOV, *reg, fs_reg(0));
}
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:
unreachable("not reached: bad math opcode");
}
/* 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 || brw->gen == 7)
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;
if (brw->gen >= 8) {
inst = emit(opcode, dst, src0, src1);
} else 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(MOV(fs_reg(MRF, base_mrf + 1, op1.type, dispatch_width), 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()
{
if (dispatch_width == 8) {
prog_data->dispatch_grf_start_reg = payload.num_regs;
} else {
assert(stage == MESA_SHADER_FRAGMENT);
brw_wm_prog_data *prog_data = (brw_wm_prog_data*) this->prog_data;
prog_data->dispatch_grf_start_reg_16 = payload.num_regs;
}
prog_data->curb_read_length = ALIGN(stage_prog_data->nr_params, 8) / 8;
/* Map the offsets in the UNIFORM file to fixed HW regs. */
foreach_block_and_inst(block, fs_inst, inst, cfg) {
for (unsigned int i = 0; i < inst->sources; i++) {
if (inst->src[i].file == UNIFORM) {
int uniform_nr = inst->src[i].reg + inst->src[i].reg_offset;
int constant_nr;
if (uniform_nr >= 0 && uniform_nr < (int) uniforms) {
constant_nr = push_constant_loc[uniform_nr];
} else {
/* Section 5.11 of the OpenGL 4.1 spec says:
* "Out-of-bounds reads return undefined values, which include
* values from other variables of the active program or zero."
* Just return the first push constant.
*/
constant_nr = 0;
}
struct brw_reg brw_reg = brw_vec1_grf(payload.num_regs +
constant_nr / 8,
constant_nr % 8);
inst->src[i].file = HW_REG;
inst->src[i].fixed_hw_reg = byte_offset(
retype(brw_reg, inst->src[i].type),
inst->src[i].subreg_offset);
}
}
}
}
void
fs_visitor::calculate_urb_setup()
{
assert(stage == MESA_SHADER_FRAGMENT);
brw_wm_prog_data *prog_data = (brw_wm_prog_data*) this->prog_data;
brw_wm_prog_key *key = (brw_wm_prog_key*) this->key;
memset(prog_data->urb_setup, -1,
sizeof(prog_data->urb_setup[0]) * VARYING_SLOT_MAX);
int urb_next = 0;
/* Figure out where each of the incoming setup attributes lands. */
if (brw->gen >= 6) {
if (_mesa_bitcount_64(prog->InputsRead &
BRW_FS_VARYING_INPUT_MASK) <= 16) {
/* The SF/SBE pipeline stage can do arbitrary rearrangement of the
* first 16 varying inputs, so we can put them wherever we want.
* Just put them in order.
*
* This is useful because it means that (a) inputs not used by the
* fragment shader won't take up valuable register space, and (b) we
* won't have to recompile the fragment shader if it gets paired with
* a different vertex (or geometry) shader.
*/
for (unsigned int i = 0; i < VARYING_SLOT_MAX; i++) {
if (prog->InputsRead & BRW_FS_VARYING_INPUT_MASK &
BITFIELD64_BIT(i)) {
prog_data->urb_setup[i] = urb_next++;
}
}
} else {
/* We have enough input varyings that the SF/SBE pipeline stage can't
* arbitrarily rearrange them to suit our whim; we have to put them
* in an order that matches the output of the previous pipeline stage
* (geometry or vertex shader).
*/
struct brw_vue_map prev_stage_vue_map;
brw_compute_vue_map(brw, &prev_stage_vue_map,
key->input_slots_valid);
int first_slot = 2 * BRW_SF_URB_ENTRY_READ_OFFSET;
assert(prev_stage_vue_map.num_slots <= first_slot + 32);
for (int slot = first_slot; slot < prev_stage_vue_map.num_slots;
slot++) {
int varying = prev_stage_vue_map.slot_to_varying[slot];
/* Note that varying == BRW_VARYING_SLOT_COUNT when a slot is
* unused.
*/
if (varying != BRW_VARYING_SLOT_COUNT &&
(prog->InputsRead & BRW_FS_VARYING_INPUT_MASK &
BITFIELD64_BIT(varying))) {
prog_data->urb_setup[varying] = slot - first_slot;
}
}
urb_next = prev_stage_vue_map.num_slots - first_slot;
}
} 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 (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))
prog_data->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 (prog->InputsRead & BITFIELD64_BIT(VARYING_SLOT_PNTC))
prog_data->urb_setup[VARYING_SLOT_PNTC] = urb_next++;
}
prog_data->num_varying_inputs = urb_next;
}
void
fs_visitor::assign_urb_setup()
{
assert(stage == MESA_SHADER_FRAGMENT);
brw_wm_prog_data *prog_data = (brw_wm_prog_data*) this->prog_data;
int urb_start = payload.num_regs + prog_data->base.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_block_and_inst(block, fs_inst, inst, cfg) {
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;
}
}
/* Each attribute is 4 setup channels, each of which is half a reg. */
this->first_non_payload_grf =
urb_start + prog_data->num_varying_inputs * 2;
}
/**
* 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;
/* Count the total number of registers */
int reg_count = 0;
int vgrf_to_reg[num_vars];
for (int i = 0; i < num_vars; i++) {
vgrf_to_reg[i] = reg_count;
reg_count += virtual_grf_sizes[i];
}
/* An array of "split points". For each register slot, this indicates
* if this slot can be separated from the previous slot. Every time an
* instruction uses multiple elements of a register (as a source or
* destination), we mark the used slots as inseparable. Then we go
* through and split the registers into the smallest pieces we can.
*/
bool split_points[reg_count];
memset(split_points, 0, sizeof(split_points));
/* Mark all used registers as fully splittable */
foreach_block_and_inst(block, fs_inst, inst, cfg) {
if (inst->dst.file == GRF) {
int reg = vgrf_to_reg[inst->dst.reg];
for (int j = 1; j < this->virtual_grf_sizes[inst->dst.reg]; j++)
split_points[reg + j] = true;
}
for (int i = 0; i < inst->sources; i++) {
if (inst->src[i].file == GRF) {
int reg = vgrf_to_reg[inst->src[i].reg];
for (int j = 1; j < this->virtual_grf_sizes[inst->src[i].reg]; j++)
split_points[reg + j] = true;
}
}
}
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.
*/
int vgrf = this->delta_x[BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC].reg;
split_points[vgrf_to_reg[vgrf] + 1] = false;
}
foreach_block_and_inst(block, fs_inst, inst, cfg) {
if (inst->dst.file == GRF) {
int reg = vgrf_to_reg[inst->dst.reg] + inst->dst.reg_offset;
for (int j = 1; j < inst->regs_written; j++)
split_points[reg + j] = false;
}
for (int i = 0; i < inst->sources; i++) {
if (inst->src[i].file == GRF) {
int reg = vgrf_to_reg[inst->src[i].reg] + inst->src[i].reg_offset;
for (int j = 1; j < inst->regs_read(this, i); j++)
split_points[reg + j] = false;
}
}
}
int new_virtual_grf[reg_count];
int new_reg_offset[reg_count];
int reg = 0;
for (int i = 0; i < num_vars; i++) {
/* The first one should always be 0 as a quick sanity check. */
assert(split_points[reg] == false);
/* j = 0 case */
new_reg_offset[reg] = 0;
reg++;
int offset = 1;
/* j > 0 case */
for (int j = 1; j < virtual_grf_sizes[i]; j++) {
/* If this is a split point, reset the offset to 0 and allocate a
* new virtual GRF for the previous offset many registers
*/
if (split_points[reg]) {
assert(offset <= MAX_VGRF_SIZE);
int grf = virtual_grf_alloc(offset);
for (int k = reg - offset; k < reg; k++)
new_virtual_grf[k] = grf;
offset = 0;
}
new_reg_offset[reg] = offset;
offset++;
reg++;
}
/* The last one gets the original register number */
assert(offset <= MAX_VGRF_SIZE);
virtual_grf_sizes[i] = offset;
for (int k = reg - offset; k < reg; k++)
new_virtual_grf[k] = i;
}
assert(reg == reg_count);
foreach_block_and_inst(block, fs_inst, inst, cfg) {
if (inst->dst.file == GRF) {
reg = vgrf_to_reg[inst->dst.reg] + inst->dst.reg_offset;
inst->dst.reg = new_virtual_grf[reg];
inst->dst.reg_offset = new_reg_offset[reg];
assert(new_reg_offset[reg] < virtual_grf_sizes[new_virtual_grf[reg]]);
}
for (int i = 0; i < inst->sources; i++) {
if (inst->src[i].file == GRF) {
reg = vgrf_to_reg[inst->src[i].reg] + inst->src[i].reg_offset;
inst->src[i].reg = new_virtual_grf[reg];
inst->src[i].reg_offset = new_reg_offset[reg];
assert(new_reg_offset[reg] < virtual_grf_sizes[new_virtual_grf[reg]]);
}
}
}
invalidate_live_intervals();
}
/**
* 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.
*/
bool
fs_visitor::compact_virtual_grfs()
{
bool progress = false;
int remap_table[this->virtual_grf_count];
memset(remap_table, -1, sizeof(remap_table));
/* Mark which virtual GRFs are used. */
foreach_block_and_inst(block, const fs_inst, inst, cfg) {
if (inst->dst.file == GRF)
remap_table[inst->dst.reg] = 0;
for (int i = 0; i < inst->sources; i++) {
if (inst->src[i].file == GRF)
remap_table[inst->src[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) {
/* We just found an unused register. This means that we are
* actually going to compact something.
*/
progress = true;
} else {
remap_table[i] = new_index;
virtual_grf_sizes[new_index] = virtual_grf_sizes[i];
invalidate_live_intervals();
++new_index;
}
}
this->virtual_grf_count = new_index;
/* Patch all the instructions to use the newly renumbered registers */
foreach_block_and_inst(block, fs_inst, inst, cfg) {
if (inst->dst.file == GRF)
inst->dst.reg = remap_table[inst->dst.reg];
for (int i = 0; i < inst->sources; i++) {
if (inst->src[i].file == GRF)
inst->src[i].reg = remap_table[inst->src[i].reg];
}
}
/* Patch all the references to delta_x/delta_y, since they're used in
* register allocation. If they're unused, switch them to BAD_FILE so
* we don't think some random VGRF is delta_x/delta_y.
*/
for (unsigned i = 0; i < ARRAY_SIZE(delta_x); i++) {
if (delta_x[i].file == GRF) {
if (remap_table[delta_x[i].reg] != -1) {
delta_x[i].reg = remap_table[delta_x[i].reg];
} else {
delta_x[i].file = BAD_FILE;
}
}
}
for (unsigned i = 0; i < ARRAY_SIZE(delta_y); i++) {
if (delta_y[i].file == GRF) {
if (remap_table[delta_y[i].reg] != -1) {
delta_y[i].reg = remap_table[delta_y[i].reg];
} else {
delta_y[i].file = BAD_FILE;
}
}
}
return progress;
}
/*
* 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()
{
if (dispatch_width != 8)
return;
pull_constant_loc = ralloc_array(mem_ctx, int, uniforms);
memset(pull_constant_loc, -1, sizeof(pull_constant_loc[0]) * uniforms);
/* 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_block_and_inst_safe(block, fs_inst, inst, cfg) {
for (int i = 0 ; i < inst->sources; 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 gl_constant_value **values = &stage_prog_data->param[uniform];
assert(param_size[uniform]);
for (int j = 0; j < param_size[uniform]; j++) {
pull_constant_loc[uniform + j] = stage_prog_data->nr_pull_params;
stage_prog_data->pull_param[stage_prog_data->nr_pull_params++] =
values[j];
}
}
}
}
}
/**
* Assign UNIFORM file registers to either push constants or pull constants.
*
* 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::assign_constant_locations()
{
/* Only the first compile (SIMD8 mode) gets to decide on locations. */
if (dispatch_width != 8)
return;
/* Find which UNIFORM registers are still in use. */
bool is_live[uniforms];
for (unsigned int i = 0; i < uniforms; i++) {
is_live[i] = false;
}
foreach_block_and_inst(block, fs_inst, inst, cfg) {
for (int i = 0; i < inst->sources; i++) {
if (inst->src[i].file != UNIFORM)
continue;
int constant_nr = inst->src[i].reg + inst->src[i].reg_offset;
if (constant_nr >= 0 && constant_nr < (int) uniforms)
is_live[constant_nr] = true;
}
}
/* Only allow 16 registers (128 uniform components) as push constants.
*
* Just demote the end of the list. We could probably do better
* here, demoting things that are rarely used in the program first.
*
* If changing this value, note the limitation about total_regs in
* brw_curbe.c.
*/
unsigned int max_push_components = 16 * 8;
unsigned int num_push_constants = 0;
push_constant_loc = ralloc_array(mem_ctx, int, uniforms);
for (unsigned int i = 0; i < uniforms; i++) {
if (!is_live[i] || pull_constant_loc[i] != -1) {
/* This UNIFORM register is either dead, or has already been demoted
* to a pull const. Mark it as no longer living in the param[] array.
*/
push_constant_loc[i] = -1;
continue;
}
if (num_push_constants < max_push_components) {
/* Retain as a push constant. Record the location in the params[]
* array.
*/
push_constant_loc[i] = num_push_constants++;
} else {
/* Demote to a pull constant. */
push_constant_loc[i] = -1;
int pull_index = stage_prog_data->nr_pull_params++;
stage_prog_data->pull_param[pull_index] = stage_prog_data->param[i];
pull_constant_loc[i] = pull_index;
}
}
stage_prog_data->nr_params = num_push_constants;
/* Up until now, the param[] array has been indexed by reg + reg_offset
* of UNIFORM registers. Condense it to only contain the uniforms we
* chose to upload as push constants.
*/
for (unsigned int i = 0; i < uniforms; i++) {
int remapped = push_constant_loc[i];
if (remapped == -1)
continue;
assert(remapped <= (int)i);
stage_prog_data->param[remapped] = stage_prog_data->param[i];
}
}
/**
* Replace UNIFORM register file access with either UNIFORM_PULL_CONSTANT_LOAD
* or VARYING_PULL_CONSTANT_LOAD instructions which load values into VGRFs.
*/
void
fs_visitor::demote_pull_constants()
{
foreach_block_and_inst (block, fs_inst, inst, cfg) {
for (int i = 0; i < inst->sources; 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;
/* Set up the annotation tracking for new generated instructions. */
base_ir = inst->ir;
current_annotation = inst->annotation;
fs_reg surf_index(stage_prog_data->binding_table.pull_constants_start);
fs_reg dst = fs_reg(this, glsl_type::float_type);
/* Generate a pull load into dst. */
if (inst->src[i].reladdr) {
exec_list list = VARYING_PULL_CONSTANT_LOAD(dst,
surf_index,
*inst->src[i].reladdr,
pull_index);
inst->insert_before(block, &list);
inst->src[i].reladdr = NULL;
} else {
fs_reg offset = fs_reg((unsigned)(pull_index * 4) & ~15);
fs_inst *pull =
new(mem_ctx) fs_inst(FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD, 8,
dst, surf_index, offset);
inst->insert_before(block, pull);
inst->src[i].set_smear(pull_index & 3);
}
/* Rewrite the instruction to use the temporary VGRF. */
inst->src[i].file = GRF;
inst->src[i].reg = dst.reg;
inst->src[i].reg_offset = 0;
inst->src[i].width = dispatch_width;
}
}
invalidate_live_intervals();
}
bool
fs_visitor::opt_algebraic()
{
bool progress = false;
foreach_block_and_inst(block, fs_inst, inst, cfg) {
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;
case BRW_OPCODE_OR:
if (inst->src[0].equals(inst->src[1])) {
inst->opcode = BRW_OPCODE_MOV;
inst->src[1] = reg_undef;
progress = true;
break;
}
break;
case BRW_OPCODE_LRP:
if (inst->src[1].equals(inst->src[2])) {
inst->opcode = BRW_OPCODE_MOV;
inst->src[0] = inst->src[1];
inst->src[1] = reg_undef;
inst->src[2] = reg_undef;
progress = true;
break;
}
break;
case BRW_OPCODE_SEL:
if (inst->src[0].equals(inst->src[1])) {
inst->opcode = BRW_OPCODE_MOV;
inst->src[1] = reg_undef;
inst->predicate = BRW_PREDICATE_NONE;
inst->predicate_inverse = false;
progress = true;
} else if (inst->saturate && inst->src[1].file == IMM) {
switch (inst->conditional_mod) {
case BRW_CONDITIONAL_LE:
case BRW_CONDITIONAL_L:
switch (inst->src[1].type) {
case BRW_REGISTER_TYPE_F:
if (inst->src[1].fixed_hw_reg.dw1.f >= 1.0f) {
inst->opcode = BRW_OPCODE_MOV;
inst->src[1] = reg_undef;
progress = true;
}
break;
default:
break;
}
break;
case BRW_CONDITIONAL_GE:
case BRW_CONDITIONAL_G:
switch (inst->src[1].type) {
case BRW_REGISTER_TYPE_F:
if (inst->src[1].fixed_hw_reg.dw1.f <= 0.0f) {
inst->opcode = BRW_OPCODE_MOV;
inst->src[1] = reg_undef;
inst->conditional_mod = BRW_CONDITIONAL_NONE;
progress = true;
}
break;
default:
break;
}
default:
break;
}
}
break;
case SHADER_OPCODE_RCP: {
fs_inst *prev = (fs_inst *)inst->prev;
if (prev->opcode == SHADER_OPCODE_SQRT) {
if (inst->src[0].equals(prev->dst)) {
inst->opcode = SHADER_OPCODE_RSQ;
inst->src[0] = prev->src[0];
progress = true;
}
}
break;
}
default:
break;
}
}
return progress;
}
bool
fs_visitor::opt_register_renaming()
{
bool progress = false;
int depth = 0;
int remap[virtual_grf_count];
memset(remap, -1, sizeof(int) * virtual_grf_count);
foreach_block_and_inst(block, fs_inst, inst, cfg) {
if (inst->opcode == BRW_OPCODE_IF || inst->opcode == BRW_OPCODE_DO) {
depth++;
} else if (inst->opcode == BRW_OPCODE_ENDIF ||
inst->opcode == BRW_OPCODE_WHILE) {
depth--;
}
/* Rewrite instruction sources. */
for (int i = 0; i < inst->sources; i++) {
if (inst->src[i].file == GRF &&
remap[inst->src[i].reg] != -1 &&
remap[inst->src[i].reg] != inst->src[i].reg) {
inst->src[i].reg = remap[inst->src[i].reg];
progress = true;
}
}
const int dst = inst->dst.reg;
if (depth == 0 &&
inst->dst.file == GRF &&
virtual_grf_sizes[inst->dst.reg] == inst->dst.width / 8 &&
!inst->is_partial_write()) {
if (remap[dst] == -1) {
remap[dst] = dst;
} else {
remap[dst] = virtual_grf_alloc(inst->dst.width / 8);
inst->dst.reg = remap[dst];
progress = true;
}
} else if (inst->dst.file == GRF &&
remap[dst] != -1 &&
remap[dst] != dst) {
inst->dst.reg = remap[dst];
progress = true;
}
}
if (progress) {
invalidate_live_intervals();
for (unsigned i = 0; i < ARRAY_SIZE(delta_x); i++) {
if (delta_x[i].file == GRF && remap[delta_x[i].reg] != -1) {
delta_x[i].reg = remap[delta_x[i].reg];
}
}
for (unsigned i = 0; i < ARRAY_SIZE(delta_y); i++) {
if (delta_y[i].file == GRF && remap[delta_y[i].reg] != -1) {
delta_y[i].reg = remap[delta_y[i].reg];
}
}
}
return progress;
}
bool
fs_visitor::compute_to_mrf()
{
bool progress = false;
int next_ip = 0;
calculate_live_intervals();
foreach_block_and_inst_safe(block, fs_inst, inst, cfg) {
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].is_contiguous() ||
inst->src[0].subreg_offset)
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 (inst->exec_size == 16) {
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.
*/
foreach_inst_in_block_reverse_starting_from(fs_inst, scan_inst, inst, block) {
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 > scan_inst->dst.width / 8)
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(block);
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 (block->start() == scan_inst)
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 < scan_inst->sources; 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 (scan_inst->exec_size == 16) {
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 && scan_inst->base_mrf != -1) {
/* 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)
invalidate_live_intervals();
return progress;
}
/**
* Once we've generated code, try to convert normal FS_OPCODE_FB_WRITE
* instructions to FS_OPCODE_REP_FB_WRITE.
*/
void
fs_visitor::emit_repclear_shader()
{
brw_wm_prog_key *key = (brw_wm_prog_key*) this->key;
int base_mrf = 1;
int color_mrf = base_mrf + 2;
fs_inst *mov = emit(MOV(vec4(brw_message_reg(color_mrf)),
fs_reg(UNIFORM, 0, BRW_REGISTER_TYPE_F)));
mov->force_writemask_all = true;
fs_inst *write;
if (key->nr_color_regions == 1) {
write = emit(FS_OPCODE_REP_FB_WRITE);
write->saturate = key->clamp_fragment_color;
write->base_mrf = color_mrf;
write->target = 0;
write->header_present = false;
write->mlen = 1;
} else {
assume(key->nr_color_regions > 0);
for (int i = 0; i < key->nr_color_regions; ++i) {
write = emit(FS_OPCODE_REP_FB_WRITE);
write->saturate = key->clamp_fragment_color;
write->base_mrf = base_mrf;
write->target = i;
write->header_present = true;
write->mlen = 3;
}
}
write->eot = true;
calculate_cfg();
assign_constant_locations();
assign_curb_setup();
/* Now that we have the uniform assigned, go ahead and force it to a vec4. */
assert(mov->src[0].file == HW_REG);
mov->src[0] = brw_vec4_grf(mov->src[0].fixed_hw_reg.nr, 0);
}
/**
* 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_block_and_inst_safe (block, fs_inst, inst, cfg) {
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(block);
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 && inst->base_mrf != -1) {
/* 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)
invalidate_live_intervals();
return progress;
}
static void
clear_deps_for_inst_src(fs_inst *inst, int dispatch_width, bool *deps,
int first_grf, int grf_len)
{
/* Clear the flag for registers that actually got read (as expected). */
for (int i = 0; i < inst->sources; 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->exec_size == 16)
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(bblock_t *block,
fs_inst *inst)
{
int write_len = inst->regs_written;
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.
*/
foreach_inst_in_block_reverse_starting_from(fs_inst, scan_inst, inst, block) {
/* If we hit control flow, assume that there *are* outstanding
* dependencies, and force their cleanup before our instruction.
*/
if (block->start() == scan_inst) {
for (int i = 0; i < write_len; i++) {
if (needs_dep[i]) {
inst->insert_before(block, DEP_RESOLVE_MOV(first_write_grf + i));
}
}
return;
}
/* 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;
if (reg >= first_write_grf &&
reg < first_write_grf + write_len &&
needs_dep[reg - first_write_grf]) {
inst->insert_before(block, DEP_RESOLVE_MOV(reg));
needs_dep[reg - first_write_grf] = false;
if (scan_inst->exec_size == 16)
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(bblock_t *block, fs_inst *inst)
{
int write_len = inst->regs_written;
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.
*/
foreach_inst_in_block_starting_from(fs_inst, scan_inst, inst, block) {
/* If we hit control flow, force resolve all remaining dependencies. */
if (block->end() == scan_inst) {
for (int i = 0; i < write_len; i++) {
if (needs_dep[i])
scan_inst->insert_before(block,
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(block, 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(block, DEP_RESOLVE_MOV(first_write_grf + i));
}
}
void
fs_visitor::insert_gen4_send_dependency_workarounds()
{
if (brw->gen != 4 || brw->is_g4x)
return;
bool progress = false;
/* Note that we're done with register allocation, so GRF fs_regs always
* have a .reg_offset of 0.
*/
foreach_block_and_inst(block, fs_inst, inst, cfg) {
if (inst->mlen != 0 && inst->dst.file == GRF) {
insert_gen4_pre_send_dependency_workarounds(block, inst);
insert_gen4_post_send_dependency_workarounds(block, inst);
progress = true;
}
}
if (progress)
invalidate_live_intervals();
}
/**
* 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_block_and_inst (block, fs_inst, inst, cfg) {
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.fixed_hw_reg.dw1.ud /= 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,
8, payload, const_offset_reg);
setup->force_writemask_all = true;
setup->ir = inst->ir;
setup->annotation = inst->annotation;
inst->insert_before(block, 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;
invalidate_live_intervals();
} 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;
}
}
}
bool
fs_visitor::lower_load_payload()
{
bool progress = false;
int vgrf_to_reg[virtual_grf_count];
int reg_count = 16; /* Leave room for MRF */
for (int i = 0; i < virtual_grf_count; ++i) {
vgrf_to_reg[i] = reg_count;
reg_count += virtual_grf_sizes[i];
}
struct {
bool written:1; /* Whether this register has ever been written */
bool force_writemask_all:1;
bool force_sechalf:1;
} metadata[reg_count];
memset(metadata, 0, sizeof(metadata));
foreach_block_and_inst_safe (block, fs_inst, inst, cfg) {
int dst_reg;
if (inst->dst.file == GRF) {
dst_reg = vgrf_to_reg[inst->dst.reg];
} else {
/* MRF */
dst_reg = inst->dst.reg;
}
if (inst->dst.file == MRF || inst->dst.file == GRF) {
bool force_sechalf = inst->force_sechalf;
bool toggle_sechalf = inst->dst.width == 16 &&
type_sz(inst->dst.type) == 4;
for (int i = 0; i < inst->regs_written; ++i) {
metadata[dst_reg + i].written = true;
metadata[dst_reg + i].force_sechalf = force_sechalf;
metadata[dst_reg + i].force_writemask_all = inst->force_writemask_all;
force_sechalf = (toggle_sechalf != force_sechalf);
}
}
if (inst->opcode == SHADER_OPCODE_LOAD_PAYLOAD) {
assert(inst->dst.file == MRF || inst->dst.file == GRF);
fs_reg dst = inst->dst;
for (int i = 0; i < inst->sources; i++) {
dst.width = inst->src[i].effective_width;
dst.type = inst->src[i].type;
if (inst->src[i].file == BAD_FILE) {
/* Do nothing but otherwise increment as normal */
} else if (dst.file == MRF &&
dst.width == 8 &&
brw->has_compr4 &&
i + 4 < inst->sources &&
inst->src[i + 4].equals(horiz_offset(inst->src[i], 8))) {
fs_reg compr4_dst = dst;
compr4_dst.reg += BRW_MRF_COMPR4;
compr4_dst.width = 16;
fs_reg compr4_src = inst->src[i];
compr4_src.width = 16;
fs_inst *mov = MOV(compr4_dst, compr4_src);
mov->force_writemask_all = true;
inst->insert_before(block, mov);
/* Mark i+4 as BAD_FILE so we don't emit a MOV for it */
inst->src[i + 4].file = BAD_FILE;
} else {
fs_inst *mov = MOV(dst, inst->src[i]);
if (inst->src[i].file == GRF) {
int src_reg = vgrf_to_reg[inst->src[i].reg] +
inst->src[i].reg_offset;
mov->force_sechalf = metadata[src_reg].force_sechalf;
mov->force_writemask_all = metadata[src_reg].force_writemask_all;
metadata[dst_reg] = metadata[src_reg];
if (dst.width * type_sz(dst.type) > 32) {
assert((!metadata[src_reg].written ||
!metadata[src_reg].force_sechalf) &&
(!metadata[src_reg + 1].written ||
metadata[src_reg + 1].force_sechalf));
metadata[dst_reg + 1] = metadata[src_reg + 1];
}
} else {
metadata[dst_reg].force_writemask_all = false;
metadata[dst_reg].force_sechalf = false;
if (dst.width == 16) {
metadata[dst_reg + 1].force_writemask_all = false;
metadata[dst_reg + 1].force_sechalf = true;
}
}
inst->insert_before(block, mov);
}
dst = offset(dst, 1);
}
inst->remove(block);
progress = true;
}
}
if (progress)
invalidate_live_intervals();
return progress;
}
void
fs_visitor::dump_instructions()
{
dump_instructions(NULL);
}
void
fs_visitor::dump_instructions(const char *name)
{
calculate_register_pressure();
FILE *file = stderr;
if (name && geteuid() != 0) {
file = fopen(name, "w");
if (!file)
file = stderr;
}
int ip = 0, max_pressure = 0;
foreach_block_and_inst(block, backend_instruction, inst, cfg) {
max_pressure = MAX2(max_pressure, regs_live_at_ip[ip]);
fprintf(file, "{%3d} %4d: ", regs_live_at_ip[ip], ip);
dump_instruction(inst, file);
++ip;
}
fprintf(file, "Maximum %3d registers live at once.\n", max_pressure);
if (file != stderr) {
fclose(file);
}
}
void
fs_visitor::dump_instruction(backend_instruction *be_inst)
{
dump_instruction(be_inst, stderr);
}
void
fs_visitor::dump_instruction(backend_instruction *be_inst, FILE *file)
{
fs_inst *inst = (fs_inst *)be_inst;
if (inst->predicate) {
fprintf(file, "(%cf0.%d) ",
inst->predicate_inverse ? '-' : '+',
inst->flag_subreg);
}
fprintf(file, "%s", brw_instruction_name(inst->opcode));
if (inst->saturate)
fprintf(file, ".sat");
if (inst->conditional_mod) {
fprintf(file, "%s", conditional_modifier[inst->conditional_mod]);
if (!inst->predicate &&
(brw->gen < 5 || (inst->opcode != BRW_OPCODE_SEL &&
inst->opcode != BRW_OPCODE_IF &&
inst->opcode != BRW_OPCODE_WHILE))) {
fprintf(file, ".f0.%d", inst->flag_subreg);
}
}
fprintf(file, "(%d) ", inst->exec_size);
switch (inst->dst.file) {
case GRF:
fprintf(file, "vgrf%d", inst->dst.reg);
if (inst->dst.width != dispatch_width)
fprintf(file, "@%d", inst->dst.width);
if (virtual_grf_sizes[inst->dst.reg] != inst->dst.width / 8 ||
inst->dst.subreg_offset)
fprintf(file, "+%d.%d",
inst->dst.reg_offset, inst->dst.subreg_offset);
break;
case MRF:
fprintf(file, "m%d", inst->dst.reg);
break;
case BAD_FILE:
fprintf(file, "(null)");
break;
case UNIFORM:
fprintf(file, "***u%d***", inst->dst.reg + inst->dst.reg_offset);
break;
case HW_REG:
if (inst->dst.fixed_hw_reg.file == BRW_ARCHITECTURE_REGISTER_FILE) {
switch (inst->dst.fixed_hw_reg.nr) {
case BRW_ARF_NULL:
fprintf(file, "null");
break;
case BRW_ARF_ADDRESS:
fprintf(file, "a0.%d", inst->dst.fixed_hw_reg.subnr);
break;
case BRW_ARF_ACCUMULATOR:
fprintf(file, "acc%d", inst->dst.fixed_hw_reg.subnr);
break;
case BRW_ARF_FLAG:
fprintf(file, "f%d.%d", inst->dst.fixed_hw_reg.nr & 0xf,
inst->dst.fixed_hw_reg.subnr);
break;
default:
fprintf(file, "arf%d.%d", inst->dst.fixed_hw_reg.nr & 0xf,
inst->dst.fixed_hw_reg.subnr);
break;
}
} else {
fprintf(file, "hw_reg%d", inst->dst.fixed_hw_reg.nr);
}
if (inst->dst.fixed_hw_reg.subnr)
fprintf(file, "+%d", inst->dst.fixed_hw_reg.subnr);
break;
default:
fprintf(file, "???");
break;
}
fprintf(file, ":%s, ", brw_reg_type_letters(inst->dst.type));
for (int i = 0; i < inst->sources; i++) {
if (inst->src[i].negate)
fprintf(file, "-");
if (inst->src[i].abs)
fprintf(file, "|");
switch (inst->src[i].file) {
case GRF:
fprintf(file, "vgrf%d", inst->src[i].reg);
if (inst->src[i].width != dispatch_width)
fprintf(file, "@%d", inst->src[i].width);
if (virtual_grf_sizes[inst->src[i].reg] != inst->src[i].width / 8 ||
inst->src[i].subreg_offset)
fprintf(file, "+%d.%d", inst->src[i].reg_offset,
inst->src[i].subreg_offset);
break;
case MRF:
fprintf(file, "***m%d***", inst->src[i].reg);
break;
case UNIFORM:
fprintf(file, "u%d", inst->src[i].reg + inst->src[i].reg_offset);
if (inst->src[i].reladdr) {
fprintf(file, "+reladdr");
} else if (inst->src[i].subreg_offset) {
fprintf(file, "+%d.%d", inst->src[i].reg_offset,
inst->src[i].subreg_offset);
}
break;
case BAD_FILE:
fprintf(file, "(null)");
break;
case IMM:
switch (inst->src[i].type) {
case BRW_REGISTER_TYPE_F:
fprintf(file, "%ff", inst->src[i].fixed_hw_reg.dw1.f);
break;
case BRW_REGISTER_TYPE_D:
fprintf(file, "%dd", inst->src[i].fixed_hw_reg.dw1.d);
break;
case BRW_REGISTER_TYPE_UD:
fprintf(file, "%uu", inst->src[i].fixed_hw_reg.dw1.ud);
break;
default:
fprintf(file, "???");
break;
}
break;
case HW_REG:
if (inst->src[i].fixed_hw_reg.negate)
fprintf(file, "-");
if (inst->src[i].fixed_hw_reg.abs)
fprintf(file, "|");
if (inst->src[i].fixed_hw_reg.file == BRW_ARCHITECTURE_REGISTER_FILE) {
switch (inst->src[i].fixed_hw_reg.nr) {
case BRW_ARF_NULL:
fprintf(file, "null");
break;
case BRW_ARF_ADDRESS:
fprintf(file, "a0.%d", inst->src[i].fixed_hw_reg.subnr);
break;
case BRW_ARF_ACCUMULATOR:
fprintf(file, "acc%d", inst->src[i].fixed_hw_reg.subnr);
break;
case BRW_ARF_FLAG:
fprintf(file, "f%d.%d", inst->src[i].fixed_hw_reg.nr & 0xf,
inst->src[i].fixed_hw_reg.subnr);
break;
default:
fprintf(file, "arf%d.%d", inst->src[i].fixed_hw_reg.nr & 0xf,
inst->src[i].fixed_hw_reg.subnr);
break;
}
} else {
fprintf(file, "hw_reg%d", inst->src[i].fixed_hw_reg.nr);
}
if (inst->src[i].fixed_hw_reg.subnr)
fprintf(file, "+%d", inst->src[i].fixed_hw_reg.subnr);
if (inst->src[i].fixed_hw_reg.abs)
fprintf(file, "|");
break;
default:
fprintf(file, "???");
break;
}
if (inst->src[i].abs)
fprintf(file, "|");
if (inst->src[i].file != IMM) {
fprintf(file, ":%s", brw_reg_type_letters(inst->src[i].type));
}
if (i < inst->sources - 1 && inst->src[i + 1].file != BAD_FILE)
fprintf(file, ", ");
}
fprintf(file, " ");
if (dispatch_width == 16 && inst->exec_size == 8) {
if (inst->force_sechalf)
fprintf(file, "2ndhalf ");
else
fprintf(file, "1sthalf ");
}
fprintf(file, "\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,
const 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 =
(prog->InputsRead & (1 << VARYING_SLOT_POS)) != 0;
unsigned barycentric_interp_modes =
(stage == MESA_SHADER_FRAGMENT) ?
((brw_wm_prog_data*) this->prog_data)->barycentric_interp_modes : 0;
assert(brw->gen >= 6);
/* R0-1: masks, pixel X/Y coordinates. */
payload.num_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)) {
payload.barycentric_coord_reg[i] = payload.num_regs;
payload.num_regs += 2;
if (dispatch_width == 16) {
payload.num_regs += 2;
}
}
}
/* R27: interpolated depth if uses source depth */
if (uses_depth) {
payload.source_depth_reg = payload.num_regs;
payload.num_regs++;
if (dispatch_width == 16) {
/* R28: interpolated depth if not SIMD8. */
payload.num_regs++;
}
}
/* R29: interpolated W set if GEN6_WM_USES_SOURCE_W. */
if (uses_depth) {
payload.source_w_reg = payload.num_regs;
payload.num_regs++;
if (dispatch_width == 16) {
/* R30: interpolated W if not SIMD8. */
payload.num_regs++;
}
}
if (stage == MESA_SHADER_FRAGMENT) {
brw_wm_prog_data *prog_data = (brw_wm_prog_data*) this->prog_data;
brw_wm_prog_key *key = (brw_wm_prog_key*) this->key;
prog_data->uses_pos_offset = key->compute_pos_offset;
/* R31: MSAA position offsets. */
if (prog_data->uses_pos_offset) {
payload.sample_pos_reg = payload.num_regs;
payload.num_regs++;
}
}
/* R32: MSAA input coverage mask */
if (prog->SystemValuesRead & SYSTEM_BIT_SAMPLE_MASK_IN) {
assert(brw->gen >= 7);
payload.sample_mask_in_reg = payload.num_regs;
payload.num_regs++;
if (dispatch_width == 16) {
/* R33: input coverage mask if not SIMD8. */
payload.num_regs++;
}
}
/* R34-: bary for 32-pixel. */
/* R58-59: interp W for 32-pixel. */
if (prog->OutputsWritten & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) {
source_depth_to_render_target = true;
}
}
void
fs_visitor::assign_binding_table_offsets()
{
assert(stage == MESA_SHADER_FRAGMENT);
brw_wm_prog_data *prog_data = (brw_wm_prog_data*) this->prog_data;
brw_wm_prog_key *key = (brw_wm_prog_key*) this->key;
uint32_t next_binding_table_offset = 0;
/* If there are no color regions, we still perform an FB write to a null
* renderbuffer, which we place at surface index 0.
*/
prog_data->binding_table.render_target_start = next_binding_table_offset;
next_binding_table_offset += MAX2(key->nr_color_regions, 1);
assign_common_binding_table_offsets(next_binding_table_offset);
}
void
fs_visitor::calculate_register_pressure()
{
invalidate_live_intervals();
calculate_live_intervals();
unsigned num_instructions = 0;
foreach_block(block, cfg)
num_instructions += block->instructions.length();
regs_live_at_ip = rzalloc_array(mem_ctx, int, num_instructions);
for (int reg = 0; reg < virtual_grf_count; reg++) {
for (int ip = virtual_grf_start[reg]; ip <= virtual_grf_end[reg]; ip++)
regs_live_at_ip[ip] += virtual_grf_sizes[reg];
}
}
/**
* Look for repeated FS_OPCODE_MOV_DISPATCH_TO_FLAGS and drop the later ones.
*
* The needs_unlit_centroid_workaround ends up producing one of these per
* channel of centroid input, so it's good to clean them up.
*
* An assumption here is that nothing ever modifies the dispatched pixels
* value that FS_OPCODE_MOV_DISPATCH_TO_FLAGS reads from, but the hardware
* dictates that anyway.
*/
void
fs_visitor::opt_drop_redundant_mov_to_flags()
{
bool flag_mov_found[2] = {false};
foreach_block_and_inst_safe(block, fs_inst, inst, cfg) {
if (inst->is_control_flow()) {
memset(flag_mov_found, 0, sizeof(flag_mov_found));
} else if (inst->opcode == FS_OPCODE_MOV_DISPATCH_TO_FLAGS) {
if (!flag_mov_found[inst->flag_subreg])
flag_mov_found[inst->flag_subreg] = true;
else
inst->remove(block);
} else if (inst->writes_flag()) {
flag_mov_found[inst->flag_subreg] = false;
}
}
}
bool
fs_visitor::run()
{
sanity_param_count = prog->Parameters->NumParameters;
bool allocated_without_spills;
assign_binding_table_offsets();
if (brw->gen >= 6)
setup_payload_gen6();
else
setup_payload_gen4();
if (0) {
emit_dummy_fs();
} else if (brw->use_rep_send && dispatch_width == 16) {
emit_repclear_shader();
allocated_without_spills = true;
} else {
if (INTEL_DEBUG & DEBUG_SHADER_TIME)
emit_shader_time_begin();
calculate_urb_setup();
if (prog->InputsRead > 0) {
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.
*/
bool uses_kill =
(stage == MESA_SHADER_FRAGMENT) &&
((brw_wm_prog_data*) this->prog_data)->uses_kill;
bool alpha_test_func =
(stage == MESA_SHADER_FRAGMENT) &&
((brw_wm_prog_key*) this->key)->alpha_test_func;
if (uses_kill || alpha_test_func) {
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_in_list(ir_instruction, ir, shader->base.ir) {
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);
if (alpha_test_func)
emit_alpha_test();
emit_fb_writes();
calculate_cfg();
split_virtual_grfs();
move_uniform_array_access_to_pull_constants();
assign_constant_locations();
demote_pull_constants();
opt_drop_redundant_mov_to_flags();
#define OPT(pass, args...) do { \
pass_num++; \
bool this_progress = pass(args); \
\
if (unlikely(INTEL_DEBUG & DEBUG_OPTIMIZER) && this_progress) { \
char filename[64]; \
snprintf(filename, 64, "fs%d-%04d-%02d-%02d-" #pass, \
dispatch_width, shader_prog ? shader_prog->Name : 0, iteration, pass_num); \
\
backend_visitor::dump_instructions(filename); \
} \
\
progress = progress || this_progress; \
} while (false)
if (unlikely(INTEL_DEBUG & DEBUG_OPTIMIZER)) {
char filename[64];
snprintf(filename, 64, "fs%d-%04d-00-start",
dispatch_width, shader_prog ? shader_prog->Name : 0);
backend_visitor::dump_instructions(filename);
}
bool progress;
int iteration = 0;
do {
progress = false;
iteration++;
int pass_num = 0;
OPT(remove_duplicate_mrf_writes);
OPT(opt_algebraic);
OPT(opt_cse);
OPT(opt_copy_propagate);
OPT(opt_peephole_predicated_break);
OPT(dead_code_eliminate);
OPT(opt_peephole_sel);
OPT(dead_control_flow_eliminate, this);
OPT(opt_register_renaming);
OPT(opt_saturate_propagation);
OPT(register_coalesce);
OPT(compute_to_mrf);
OPT(compact_virtual_grfs);
} while (progress);
if (lower_load_payload()) {
split_virtual_grfs();
register_coalesce();
compute_to_mrf();
dead_code_eliminate();
}
lower_uniform_pull_constant_loads();
assign_curb_setup();
assign_urb_setup();
static enum instruction_scheduler_mode pre_modes[] = {
SCHEDULE_PRE,
SCHEDULE_PRE_NON_LIFO,
SCHEDULE_PRE_LIFO,
};
/* Try each scheduling heuristic to see if it can successfully register
* allocate without spilling. They should be ordered by decreasing
* performance but increasing likelihood of allocating.
*/
for (unsigned i = 0; i < ARRAY_SIZE(pre_modes); i++) {
schedule_instructions(pre_modes[i]);
if (0) {
assign_regs_trivial();
allocated_without_spills = true;
} else {
allocated_without_spills = assign_regs(false);
}
if (allocated_without_spills)
break;
}
if (!allocated_without_spills) {
/* We assume that any spilling is worse than just dropping back to
* SIMD8. There's probably actually some intermediate point where
* SIMD16 with a couple of spills is still better.
*/
if (dispatch_width == 16) {
fail("Failure to register allocate. Reduce number of "
"live scalar values to avoid this.");
} else {
perf_debug("Fragment shader triggered register spilling. "
"Try reducing the number of live scalar values to "
"improve performance.\n");
}
/* Since we're out of heuristics, just go spill registers until we
* get an allocation.
*/
while (!assign_regs(true)) {
if (failed)
break;
}
}
}
assert(force_uncompressed_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;
if (!allocated_without_spills)
schedule_instructions(SCHEDULE_POST);
if (last_scratch > 0) {
prog_data->total_scratch = brw_get_scratch_size(last_scratch);
}
if (stage == MESA_SHADER_FRAGMENT) {
brw_wm_prog_data *prog_data = (brw_wm_prog_data*) this->prog_data;
if (dispatch_width == 8)
prog_data->reg_blocks = brw_register_blocks(grf_used);
else
prog_data->reg_blocks_16 = brw_register_blocks(grf_used);
}
/* 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 == prog->Parameters->NumParameters);
return !failed;
}
const unsigned *
brw_wm_fs_emit(struct brw_context *brw,
void *mem_ctx,
const struct brw_wm_prog_key *key,
struct brw_wm_prog_data *prog_data,
struct gl_fragment_program *fp,
struct gl_shader_program *prog,
unsigned *final_assembly_size)
{
bool start_busy = false;
double 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))
brw_dump_ir(brw, "fragment", prog, &shader->base, &fp->Base);
/* Now the main event: Visit the shader IR and generate our FS IR for it.
*/
fs_visitor v(brw, mem_ctx, key, prog_data, 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;
}
cfg_t *simd16_cfg = NULL;
fs_visitor v2(brw, mem_ctx, key, prog_data, prog, fp, 16);
if (brw->gen >= 5 && likely(!(INTEL_DEBUG & DEBUG_NO16) ||
brw->use_rep_send)) {
if (!v.simd16_unsupported) {
/* Try a SIMD16 compile */
v2.import_uniforms(&v);
if (!v2.run()) {
perf_debug("SIMD16 shader failed to compile, falling back to "
"SIMD8 at a 10-20%% performance cost: %s", v2.fail_msg);
} else {
simd16_cfg = v2.cfg;
}
} else {
perf_debug("SIMD16 shader unsupported, falling back to "
"SIMD8 at a 10-20%% performance cost: %s", v.no16_msg);
}
}
cfg_t *simd8_cfg;
int no_simd8 = (INTEL_DEBUG & DEBUG_NO8) || brw->no_simd8;
if (no_simd8 && simd16_cfg) {
simd8_cfg = NULL;
prog_data->no_8 = true;
} else {
simd8_cfg = v.cfg;
prog_data->no_8 = false;
}
const unsigned *assembly = NULL;
fs_generator g(brw, mem_ctx, key, prog_data, prog, fp,
v.runtime_check_aads_emit, INTEL_DEBUG & DEBUG_WM);
assembly = g.generate_assembly(simd8_cfg, simd16_cfg,
final_assembly_size);
if (unlikely(brw->perf_debug) && shader) {
if (shader->compiled_once)
brw_wm_debug_recompile(brw, prog, 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 assembly;
}
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 || _mesa_bitcount_64(fp->Base.InputsRead &
BRW_FS_VARYING_INPUT_MASK) > 16)
key.input_slots_valid = fp->Base.InputsRead | VARYING_BIT_POS;
unsigned sampler_count = _mesa_fls(fp->Base.SamplersUsed);
for (unsigned i = 0; i < sampler_count; 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;
}
key.nr_color_regions = _mesa_bitcount_64(fp->Base.OutputsWritten &
~(BITFIELD64_BIT(FRAG_RESULT_DEPTH) |
BITFIELD64_BIT(FRAG_RESULT_SAMPLE_MASK)));
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;
}
/* GL_FRAGMENT_SHADER_DERIVATIVE_HINT is almost always GL_DONT_CARE. The
* quality of the derivatives is likely to be determined by the driconf
* option.
*/
key.high_quality_derivatives = brw->disable_derivative_optimization;
key.program_string_id = bfp->id;
uint32_t old_prog_offset = brw->wm.base.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.base.prog_offset = old_prog_offset;
brw->wm.prog_data = old_prog_data;
return success;
}