/*
* Copyright © 2010 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
/** @file brw_fs.cpp
*
* This file drives the GLSL IR -> LIR translation, contains the
* optimizations on the LIR, and drives the generation of native code
* from the LIR.
*/
extern "C" {
#include <sys/types.h>
#include "main/macros.h"
#include "main/shaderobj.h"
#include "main/uniforms.h"
#include "main/fbobject.h"
#include "program/prog_parameter.h"
#include "program/prog_print.h"
#include "program/register_allocate.h"
#include "program/sampler.h"
#include "program/hash_table.h"
#include "brw_context.h"
#include "brw_eu.h"
#include "brw_wm.h"
}
#include "brw_shader.h"
#include "brw_fs.h"
#include "glsl/glsl_types.h"
#include "glsl/ir_print_visitor.h"
void
fs_inst::init()
{
memset(this, 0, sizeof(*this));
this->opcode = BRW_OPCODE_NOP;
this->conditional_mod = BRW_CONDITIONAL_NONE;
this->dst = reg_undef;
this->src[0] = reg_undef;
this->src[1] = reg_undef;
this->src[2] = reg_undef;
}
fs_inst::fs_inst()
{
init();
}
fs_inst::fs_inst(enum opcode opcode)
{
init();
this->opcode = opcode;
}
fs_inst::fs_inst(enum opcode opcode, fs_reg dst)
{
init();
this->opcode = opcode;
this->dst = dst;
if (dst.file == GRF)
assert(dst.reg_offset >= 0);
}
fs_inst::fs_inst(enum opcode opcode, fs_reg dst, fs_reg src0)
{
init();
this->opcode = opcode;
this->dst = dst;
this->src[0] = src0;
if (dst.file == GRF)
assert(dst.reg_offset >= 0);
if (src[0].file == GRF)
assert(src[0].reg_offset >= 0);
}
fs_inst::fs_inst(enum opcode opcode, fs_reg dst, fs_reg src0, fs_reg src1)
{
init();
this->opcode = opcode;
this->dst = dst;
this->src[0] = src0;
this->src[1] = src1;
if (dst.file == GRF)
assert(dst.reg_offset >= 0);
if (src[0].file == GRF)
assert(src[0].reg_offset >= 0);
if (src[1].file == GRF)
assert(src[1].reg_offset >= 0);
}
fs_inst::fs_inst(enum opcode opcode, fs_reg dst,
fs_reg src0, fs_reg src1, fs_reg src2)
{
init();
this->opcode = opcode;
this->dst = dst;
this->src[0] = src0;
this->src[1] = src1;
this->src[2] = src2;
if (dst.file == GRF)
assert(dst.reg_offset >= 0);
if (src[0].file == GRF)
assert(src[0].reg_offset >= 0);
if (src[1].file == GRF)
assert(src[1].reg_offset >= 0);
if (src[2].file == GRF)
assert(src[2].reg_offset >= 0);
}
bool
fs_inst::equals(fs_inst *inst)
{
return (opcode == inst->opcode &&
dst.equals(inst->dst) &&
src[0].equals(inst->src[0]) &&
src[1].equals(inst->src[1]) &&
src[2].equals(inst->src[2]) &&
saturate == inst->saturate &&
predicated == inst->predicated &&
conditional_mod == inst->conditional_mod &&
mlen == inst->mlen &&
base_mrf == inst->base_mrf &&
sampler == inst->sampler &&
target == inst->target &&
eot == inst->eot &&
header_present == inst->header_present &&
shadow_compare == inst->shadow_compare &&
offset == inst->offset);
}
int
fs_inst::regs_written()
{
if (is_tex())
return 4;
/* The SINCOS and INT_DIV_QUOTIENT_AND_REMAINDER math functions return 2,
* but we don't currently use them...nor do we have an opcode for them.
*/
return 1;
}
bool
fs_inst::overwrites_reg(const fs_reg ®)
{
return (reg.file == dst.file &&
reg.reg == dst.reg &&
reg.reg_offset >= dst.reg_offset &&
reg.reg_offset < dst.reg_offset + regs_written());
}
bool
fs_inst::is_tex()
{
return (opcode == SHADER_OPCODE_TEX ||
opcode == FS_OPCODE_TXB ||
opcode == SHADER_OPCODE_TXD ||
opcode == SHADER_OPCODE_TXF ||
opcode == SHADER_OPCODE_TXL ||
opcode == SHADER_OPCODE_TXS);
}
bool
fs_inst::is_math()
{
return (opcode == SHADER_OPCODE_RCP ||
opcode == SHADER_OPCODE_RSQ ||
opcode == SHADER_OPCODE_SQRT ||
opcode == SHADER_OPCODE_EXP2 ||
opcode == SHADER_OPCODE_LOG2 ||
opcode == SHADER_OPCODE_SIN ||
opcode == SHADER_OPCODE_COS ||
opcode == SHADER_OPCODE_INT_QUOTIENT ||
opcode == SHADER_OPCODE_INT_REMAINDER ||
opcode == SHADER_OPCODE_POW);
}
void
fs_reg::init()
{
memset(this, 0, sizeof(*this));
this->smear = -1;
}
/** Generic unset register constructor. */
fs_reg::fs_reg()
{
init();
this->file = BAD_FILE;
}
/** Immediate value constructor. */
fs_reg::fs_reg(float f)
{
init();
this->file = IMM;
this->type = BRW_REGISTER_TYPE_F;
this->imm.f = f;
}
/** Immediate value constructor. */
fs_reg::fs_reg(int32_t i)
{
init();
this->file = IMM;
this->type = BRW_REGISTER_TYPE_D;
this->imm.i = i;
}
/** Immediate value constructor. */
fs_reg::fs_reg(uint32_t u)
{
init();
this->file = IMM;
this->type = BRW_REGISTER_TYPE_UD;
this->imm.u = u;
}
/** Fixed brw_reg Immediate value constructor. */
fs_reg::fs_reg(struct brw_reg fixed_hw_reg)
{
init();
this->file = FIXED_HW_REG;
this->fixed_hw_reg = fixed_hw_reg;
this->type = fixed_hw_reg.type;
}
bool
fs_reg::equals(const fs_reg &r) const
{
return (file == r.file &&
reg == r.reg &&
reg_offset == r.reg_offset &&
type == r.type &&
negate == r.negate &&
abs == r.abs &&
memcmp(&fixed_hw_reg, &r.fixed_hw_reg,
sizeof(fixed_hw_reg)) == 0 &&
smear == r.smear &&
imm.u == r.imm.u);
}
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;
default:
assert(!"not reached");
return 0;
}
}
void
fs_visitor::fail(const char *format, ...)
{
va_list va;
char *msg;
if (failed)
return;
failed = true;
va_start(va, format);
msg = ralloc_vasprintf(mem_ctx, format, va);
va_end(va);
msg = ralloc_asprintf(mem_ctx, "FS compile failed: %s\n", msg);
this->fail_msg = msg;
if (INTEL_DEBUG & DEBUG_WM) {
fprintf(stderr, "%s", msg);
}
}
fs_inst *
fs_visitor::emit(enum opcode opcode)
{
return emit(fs_inst(opcode));
}
fs_inst *
fs_visitor::emit(enum opcode opcode, fs_reg dst)
{
return emit(fs_inst(opcode, dst));
}
fs_inst *
fs_visitor::emit(enum opcode opcode, fs_reg dst, fs_reg src0)
{
return emit(fs_inst(opcode, dst, src0));
}
fs_inst *
fs_visitor::emit(enum opcode opcode, fs_reg dst, fs_reg src0, fs_reg src1)
{
return emit(fs_inst(opcode, dst, src0, src1));
}
fs_inst *
fs_visitor::emit(enum opcode opcode, fs_reg dst,
fs_reg src0, fs_reg src1, fs_reg src2)
{
return emit(fs_inst(opcode, dst, src0, src1, src2));
}
void
fs_visitor::push_force_uncompressed()
{
force_uncompressed_stack++;
}
void
fs_visitor::pop_force_uncompressed()
{
force_uncompressed_stack--;
assert(force_uncompressed_stack >= 0);
}
void
fs_visitor::push_force_sechalf()
{
force_sechalf_stack++;
}
void
fs_visitor::pop_force_sechalf()
{
force_sechalf_stack--;
assert(force_sechalf_stack >= 0);
}
/**
* Returns how many MRFs an FS opcode will write over.
*
* Note that this is not the 0 or 1 implied writes in an actual gen
* instruction -- the FS opcodes often generate MOVs in addition.
*/
int
fs_visitor::implied_mrf_writes(fs_inst *inst)
{
if (inst->mlen == 0)
return 0;
switch (inst->opcode) {
case SHADER_OPCODE_RCP:
case SHADER_OPCODE_RSQ:
case SHADER_OPCODE_SQRT:
case SHADER_OPCODE_EXP2:
case SHADER_OPCODE_LOG2:
case SHADER_OPCODE_SIN:
case SHADER_OPCODE_COS:
return 1 * c->dispatch_width / 8;
case SHADER_OPCODE_POW:
case SHADER_OPCODE_INT_QUOTIENT:
case SHADER_OPCODE_INT_REMAINDER:
return 2 * c->dispatch_width / 8;
case SHADER_OPCODE_TEX:
case FS_OPCODE_TXB:
case SHADER_OPCODE_TXD:
case SHADER_OPCODE_TXF:
case SHADER_OPCODE_TXL:
case SHADER_OPCODE_TXS:
return 1;
case FS_OPCODE_FB_WRITE:
return 2;
case FS_OPCODE_PULL_CONSTANT_LOAD:
case FS_OPCODE_UNSPILL:
return 1;
case FS_OPCODE_SPILL:
return 2;
default:
assert(!"not reached");
return inst->mlen;
}
}
int
fs_visitor::virtual_grf_alloc(int size)
{
if (virtual_grf_array_size <= virtual_grf_count) {
if (virtual_grf_array_size == 0)
virtual_grf_array_size = 16;
else
virtual_grf_array_size *= 2;
virtual_grf_sizes = reralloc(mem_ctx, virtual_grf_sizes, int,
virtual_grf_array_size);
}
virtual_grf_sizes[virtual_grf_count] = size;
return virtual_grf_count++;
}
/** Fixed HW reg constructor. */
fs_reg::fs_reg(enum register_file file, int reg)
{
init();
this->file = file;
this->reg = reg;
this->type = BRW_REGISTER_TYPE_F;
}
/** Fixed HW reg constructor. */
fs_reg::fs_reg(enum register_file file, int reg, uint32_t type)
{
init();
this->file = file;
this->reg = reg;
this->type = type;
}
/** Automatic reg constructor. */
fs_reg::fs_reg(class fs_visitor *v, const struct glsl_type *type)
{
init();
this->file = GRF;
this->reg = v->virtual_grf_alloc(v->type_size(type));
this->reg_offset = 0;
this->type = brw_type_for_base_type(type);
}
fs_reg *
fs_visitor::variable_storage(ir_variable *var)
{
return (fs_reg *)hash_table_find(this->variable_ht, var);
}
void
import_uniforms_callback(const void *key,
void *data,
void *closure)
{
struct hash_table *dst_ht = (struct hash_table *)closure;
const fs_reg *reg = (const fs_reg *)data;
if (reg->file != UNIFORM)
return;
hash_table_insert(dst_ht, data, key);
}
/* For 16-wide, we need to follow from the uniform setup of 8-wide dispatch.
* This brings in those uniform definitions
*/
void
fs_visitor::import_uniforms(fs_visitor *v)
{
hash_table_call_foreach(v->variable_ht,
import_uniforms_callback,
variable_ht);
this->params_remap = v->params_remap;
}
/* 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.
*/
int
fs_visitor::setup_uniform_values(int loc, const glsl_type *type)
{
unsigned int offset = 0;
if (type->is_matrix()) {
const glsl_type *column = glsl_type::get_instance(GLSL_TYPE_FLOAT,
type->vector_elements,
1);
for (unsigned int i = 0; i < type->matrix_columns; i++) {
offset += setup_uniform_values(loc + offset, column);
}
return offset;
}
switch (type->base_type) {
case GLSL_TYPE_FLOAT:
case GLSL_TYPE_UINT:
case GLSL_TYPE_INT:
case GLSL_TYPE_BOOL:
for (unsigned int i = 0; i < type->vector_elements; i++) {
unsigned int param = c->prog_data.nr_params++;
assert(param < ARRAY_SIZE(c->prog_data.param));
this->param_index[param] = loc;
this->param_offset[param] = i;
}
return 1;
case GLSL_TYPE_STRUCT:
for (unsigned int i = 0; i < type->length; i++) {
offset += setup_uniform_values(loc + offset,
type->fields.structure[i].type);
}
return offset;
case GLSL_TYPE_ARRAY:
for (unsigned int i = 0; i < type->length; i++) {
offset += setup_uniform_values(loc + offset, type->fields.array);
}
return offset;
case GLSL_TYPE_SAMPLER:
/* The sampler takes up a slot, but we don't use any values from it. */
return 1;
default:
assert(!"not reached");
return 0;
}
}
/* Our support for builtin uniforms is even scarier than non-builtin.
* It sits on top of the PROG_STATE_VAR parameters that are
* automatically updated from GL context state.
*/
void
fs_visitor::setup_builtin_uniform_values(ir_variable *ir)
{
const ir_state_slot *const slots = ir->state_slots;
assert(ir->state_slots != NULL);
for (unsigned int i = 0; i < ir->num_state_slots; i++) {
/* This state reference has already been setup by ir_to_mesa, but we'll
* get the same index back here.
*/
int index = _mesa_add_state_reference(this->fp->Base.Parameters,
(gl_state_index *)slots[i].tokens);
/* Add each of the unique swizzles of the element as a parameter.
* This'll end up matching the expected layout of the
* array/matrix/structure we're trying to fill in.
*/
int last_swiz = -1;
for (unsigned int j = 0; j < 4; j++) {
int swiz = GET_SWZ(slots[i].swizzle, j);
if (swiz == last_swiz)
break;
last_swiz = swiz;
this->param_index[c->prog_data.nr_params] = index;
this->param_offset[c->prog_data.nr_params] = swiz;
c->prog_data.nr_params++;
}
}
}
fs_reg *
fs_visitor::emit_fragcoord_interpolation(ir_variable *ir)
{
fs_reg *reg = new(this->mem_ctx) fs_reg(this, ir->type);
fs_reg wpos = *reg;
bool flip = !ir->origin_upper_left ^ c->key.render_to_fbo;
/* gl_FragCoord.x */
if (ir->pixel_center_integer) {
emit(BRW_OPCODE_MOV, wpos, this->pixel_x);
} else {
emit(BRW_OPCODE_ADD, wpos, this->pixel_x, fs_reg(0.5f));
}
wpos.reg_offset++;
/* gl_FragCoord.y */
if (!flip && ir->pixel_center_integer) {
emit(BRW_OPCODE_MOV, wpos, this->pixel_y);
} else {
fs_reg pixel_y = this->pixel_y;
float offset = (ir->pixel_center_integer ? 0.0 : 0.5);
if (flip) {
pixel_y.negate = true;
offset += c->key.drawable_height - 1.0;
}
emit(BRW_OPCODE_ADD, wpos, pixel_y, fs_reg(offset));
}
wpos.reg_offset++;
/* gl_FragCoord.z */
if (intel->gen >= 6) {
emit(BRW_OPCODE_MOV, wpos,
fs_reg(brw_vec8_grf(c->source_depth_reg, 0)));
} else {
emit(FS_OPCODE_LINTERP, wpos,
this->delta_x[BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC],
this->delta_y[BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC],
interp_reg(FRAG_ATTRIB_WPOS, 2));
}
wpos.reg_offset++;
/* gl_FragCoord.w: Already set up in emit_interpolation */
emit(BRW_OPCODE_MOV, wpos, this->wpos_w);
return reg;
}
fs_inst *
fs_visitor::emit_linterp(const fs_reg &attr, const fs_reg &interp,
glsl_interp_qualifier interpolation_mode,
bool is_centroid)
{
brw_wm_barycentric_interp_mode barycoord_mode;
if (is_centroid) {
if (interpolation_mode == INTERP_QUALIFIER_SMOOTH)
barycoord_mode = BRW_WM_PERSPECTIVE_CENTROID_BARYCENTRIC;
else
barycoord_mode = BRW_WM_NONPERSPECTIVE_CENTROID_BARYCENTRIC;
} else {
if (interpolation_mode == INTERP_QUALIFIER_SMOOTH)
barycoord_mode = BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC;
else
barycoord_mode = BRW_WM_NONPERSPECTIVE_PIXEL_BARYCENTRIC;
}
return emit(FS_OPCODE_LINTERP, attr,
this->delta_x[barycoord_mode],
this->delta_y[barycoord_mode], interp);
}
fs_reg *
fs_visitor::emit_general_interpolation(ir_variable *ir)
{
fs_reg *reg = new(this->mem_ctx) fs_reg(this, ir->type);
reg->type = brw_type_for_base_type(ir->type->get_scalar_type());
fs_reg attr = *reg;
unsigned int array_elements;
const glsl_type *type;
if (ir->type->is_array()) {
array_elements = ir->type->length;
if (array_elements == 0) {
fail("dereferenced array '%s' has length 0\n", ir->name);
}
type = ir->type->fields.array;
} else {
array_elements = 1;
type = ir->type;
}
glsl_interp_qualifier interpolation_mode =
ir->determine_interpolation_mode(c->key.flat_shade);
int location = ir->location;
for (unsigned int i = 0; i < array_elements; i++) {
for (unsigned int j = 0; j < type->matrix_columns; j++) {
if (urb_setup[location] == -1) {
/* If there's no incoming setup data for this slot, don't
* emit interpolation for it.
*/
attr.reg_offset += type->vector_elements;
location++;
continue;
}
if (interpolation_mode == INTERP_QUALIFIER_FLAT) {
/* Constant interpolation (flat shading) case. The SF has
* handed us defined values in only the constant offset
* field of the setup reg.
*/
for (unsigned int k = 0; k < type->vector_elements; k++) {
struct brw_reg interp = interp_reg(location, k);
interp = suboffset(interp, 3);
interp.type = reg->type;
emit(FS_OPCODE_CINTERP, attr, fs_reg(interp));
attr.reg_offset++;
}
} else {
/* Smooth/noperspective interpolation case. */
for (unsigned int k = 0; k < type->vector_elements; k++) {
/* FINISHME: At some point we probably want to push
* this farther by giving similar treatment to the
* other potentially constant components of the
* attribute, as well as making brw_vs_constval.c
* handle varyings other than gl_TexCoord.
*/
if (location >= FRAG_ATTRIB_TEX0 &&
location <= FRAG_ATTRIB_TEX7 &&
k == 3 && !(c->key.proj_attrib_mask & (1 << location))) {
emit(BRW_OPCODE_MOV, attr, fs_reg(1.0f));
} else {
struct brw_reg interp = interp_reg(location, k);
emit_linterp(attr, fs_reg(interp), interpolation_mode,
ir->centroid);
if (brw->needs_unlit_centroid_workaround && ir->centroid) {
/* Get the pixel/sample mask into f0 so that we know
* which pixels are lit. Then, for each channel that is
* unlit, replace the centroid data with non-centroid
* data.
*/
emit(FS_OPCODE_MOV_DISPATCH_TO_FLAGS, attr);
fs_inst *inst = emit_linterp(attr, fs_reg(interp),
interpolation_mode, false);
inst->predicated = true;
inst->predicate_inverse = true;
}
if (intel->gen < 6) {
emit(BRW_OPCODE_MUL, attr, attr, this->pixel_w);
}
}
attr.reg_offset++;
}
}
location++;
}
}
return reg;
}
fs_reg *
fs_visitor::emit_frontfacing_interpolation(ir_variable *ir)
{
fs_reg *reg = new(this->mem_ctx) fs_reg(this, ir->type);
/* The frontfacing comes in as a bit in the thread payload. */
if (intel->gen >= 6) {
emit(BRW_OPCODE_ASR, *reg,
fs_reg(retype(brw_vec1_grf(0, 0), BRW_REGISTER_TYPE_D)),
fs_reg(15));
emit(BRW_OPCODE_NOT, *reg, *reg);
emit(BRW_OPCODE_AND, *reg, *reg, fs_reg(1));
} else {
struct brw_reg r1_6ud = retype(brw_vec1_grf(1, 6), BRW_REGISTER_TYPE_UD);
/* bit 31 is "primitive is back face", so checking < (1 << 31) gives
* us front face
*/
fs_inst *inst = emit(BRW_OPCODE_CMP, *reg,
fs_reg(r1_6ud),
fs_reg(1u << 31));
inst->conditional_mod = BRW_CONDITIONAL_L;
emit(BRW_OPCODE_AND, *reg, *reg, fs_reg(1u));
}
return reg;
}
fs_inst *
fs_visitor::emit_math(enum opcode opcode, fs_reg dst, fs_reg src)
{
switch (opcode) {
case SHADER_OPCODE_RCP:
case SHADER_OPCODE_RSQ:
case SHADER_OPCODE_SQRT:
case SHADER_OPCODE_EXP2:
case SHADER_OPCODE_LOG2:
case SHADER_OPCODE_SIN:
case SHADER_OPCODE_COS:
break;
default:
assert(!"not reached: bad math opcode");
return NULL;
}
/* Can't do hstride == 0 args to gen6 math, so expand it out. We
* might be able to do better by doing execsize = 1 math and then
* expanding that result out, but we would need to be careful with
* masking.
*
* Gen 6 hardware ignores source modifiers (negate and abs) on math
* instructions, so we also move to a temp to set those up.
*/
if (intel->gen == 6 && (src.file == UNIFORM ||
src.abs ||
src.negate)) {
fs_reg expanded = fs_reg(this, glsl_type::float_type);
emit(BRW_OPCODE_MOV, expanded, src);
src = expanded;
}
fs_inst *inst = emit(opcode, dst, src);
if (intel->gen < 6) {
inst->base_mrf = 2;
inst->mlen = c->dispatch_width / 8;
}
return inst;
}
fs_inst *
fs_visitor::emit_math(enum opcode opcode, fs_reg dst, fs_reg src0, fs_reg src1)
{
int base_mrf = 2;
fs_inst *inst;
switch (opcode) {
case SHADER_OPCODE_POW:
case SHADER_OPCODE_INT_QUOTIENT:
case SHADER_OPCODE_INT_REMAINDER:
break;
default:
assert(!"not reached: unsupported binary math opcode.");
return NULL;
}
if (intel->gen >= 7) {
inst = emit(opcode, dst, src0, src1);
} else if (intel->gen == 6) {
/* Can't do hstride == 0 args to gen6 math, so expand it out.
*
* The hardware ignores source modifiers (negate and abs) on math
* instructions, so we also move to a temp to set those up.
*/
if (src0.file == UNIFORM || src0.abs || src0.negate) {
fs_reg expanded = fs_reg(this, glsl_type::float_type);
expanded.type = src0.type;
emit(BRW_OPCODE_MOV, expanded, src0);
src0 = expanded;
}
if (src1.file == UNIFORM || src1.abs || src1.negate) {
fs_reg expanded = fs_reg(this, glsl_type::float_type);
expanded.type = src1.type;
emit(BRW_OPCODE_MOV, expanded, src1);
src1 = expanded;
}
inst = emit(opcode, dst, src0, src1);
} else {
/* From the Ironlake PRM, Volume 4, Part 1, Section 6.1.13
* "Message Payload":
*
* "Operand0[7]. For the INT DIV functions, this operand is the
* denominator."
* ...
* "Operand1[7]. For the INT DIV functions, this operand is the
* numerator."
*/
bool is_int_div = opcode != SHADER_OPCODE_POW;
fs_reg &op0 = is_int_div ? src1 : src0;
fs_reg &op1 = is_int_div ? src0 : src1;
emit(BRW_OPCODE_MOV, fs_reg(MRF, base_mrf + 1, op1.type), op1);
inst = emit(opcode, dst, op0, reg_null_f);
inst->base_mrf = base_mrf;
inst->mlen = 2 * c->dispatch_width / 8;
}
return inst;
}
/**
* To be called after the last _mesa_add_state_reference() call, to
* set up prog_data.param[] for assign_curb_setup() and
* setup_pull_constants().
*/
void
fs_visitor::setup_paramvalues_refs()
{
if (c->dispatch_width != 8)
return;
/* Set up the pointers to ParamValues now that that array is finalized. */
for (unsigned int i = 0; i < c->prog_data.nr_params; i++) {
c->prog_data.param[i] =
(const float *)fp->Base.Parameters->ParameterValues[this->param_index[i]] +
this->param_offset[i];
}
}
void
fs_visitor::assign_curb_setup()
{
c->prog_data.curb_read_length = ALIGN(c->prog_data.nr_params, 8) / 8;
if (c->dispatch_width == 8) {
c->prog_data.first_curbe_grf = c->nr_payload_regs;
} else {
c->prog_data.first_curbe_grf_16 = c->nr_payload_regs;
}
/* Map the offsets in the UNIFORM file to fixed HW regs. */
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
for (unsigned int i = 0; i < 3; i++) {
if (inst->src[i].file == UNIFORM) {
int constant_nr = inst->src[i].reg + inst->src[i].reg_offset;
struct brw_reg brw_reg = brw_vec1_grf(c->nr_payload_regs +
constant_nr / 8,
constant_nr % 8);
inst->src[i].file = FIXED_HW_REG;
inst->src[i].fixed_hw_reg = retype(brw_reg, inst->src[i].type);
}
}
}
}
void
fs_visitor::calculate_urb_setup()
{
for (unsigned int i = 0; i < FRAG_ATTRIB_MAX; i++) {
urb_setup[i] = -1;
}
int urb_next = 0;
/* Figure out where each of the incoming setup attributes lands. */
if (intel->gen >= 6) {
for (unsigned int i = 0; i < FRAG_ATTRIB_MAX; i++) {
if (fp->Base.InputsRead & BITFIELD64_BIT(i)) {
urb_setup[i] = urb_next++;
}
}
} else {
/* FINISHME: The sf doesn't map VS->FS inputs for us very well. */
for (unsigned int i = 0; i < VERT_RESULT_MAX; i++) {
/* Point size is packed into the header, not as a general attribute */
if (i == VERT_RESULT_PSIZ)
continue;
if (c->key.vp_outputs_written & BITFIELD64_BIT(i)) {
int fp_index = _mesa_vert_result_to_frag_attrib((gl_vert_result) 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 (fp_index >= 0)
urb_setup[fp_index] = urb_next;
urb_next++;
}
}
/*
* It's a FS only attribute, and we did interpolation for this attribute
* in SF thread. So, count it here, too.
*
* See compile_sf_prog() for more info.
*/
if (fp->Base.InputsRead & BITFIELD64_BIT(FRAG_ATTRIB_PNTC))
urb_setup[FRAG_ATTRIB_PNTC] = urb_next++;
}
/* Each attribute is 4 setup channels, each of which is half a reg. */
c->prog_data.urb_read_length = urb_next * 2;
}
void
fs_visitor::assign_urb_setup()
{
int urb_start = c->nr_payload_regs + c->prog_data.curb_read_length;
/* Offset all the urb_setup[] index by the actual position of the
* setup regs, now that the location of the constants has been chosen.
*/
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
if (inst->opcode == FS_OPCODE_LINTERP) {
assert(inst->src[2].file == FIXED_HW_REG);
inst->src[2].fixed_hw_reg.nr += urb_start;
}
if (inst->opcode == FS_OPCODE_CINTERP) {
assert(inst->src[0].file == FIXED_HW_REG);
inst->src[0].fixed_hw_reg.nr += urb_start;
}
}
this->first_non_payload_grf = urb_start + c->prog_data.urb_read_length;
}
/**
* Split large virtual GRFs into separate components if we can.
*
* This is mostly duplicated with what brw_fs_vector_splitting does,
* but that's really conservative because it's afraid of doing
* splitting that doesn't result in real progress after the rest of
* the optimization phases, which would cause infinite looping in
* optimization. We can do it once here, safely. This also has the
* opportunity to split interpolated values, or maybe even uniforms,
* which we don't have at the IR level.
*
* We want to split, because virtual GRFs are what we register
* allocate and spill (due to contiguousness requirements for some
* instructions), and they're what we naturally generate in the
* codegen process, but most virtual GRFs don't actually need to be
* contiguous sets of GRFs. If we split, we'll end up with reduced
* live intervals and better dead code elimination and coalescing.
*/
void
fs_visitor::split_virtual_grfs()
{
int num_vars = this->virtual_grf_count;
bool split_grf[num_vars];
int new_virtual_grf[num_vars];
/* Try to split anything > 0 sized. */
for (int i = 0; i < num_vars; i++) {
if (this->virtual_grf_sizes[i] != 1)
split_grf[i] = true;
else
split_grf[i] = false;
}
if (brw->has_pln &&
this->delta_x[BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC].file == GRF) {
/* PLN opcodes rely on the delta_xy being contiguous. We only have to
* check this for BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC, because prior to
* Gen6, that was the only supported interpolation mode, and since Gen6,
* delta_x and delta_y are in fixed hardware registers.
*/
split_grf[this->delta_x[BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC].reg] =
false;
}
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
/* If there's a SEND message that requires contiguous destination
* registers, no splitting is allowed.
*/
if (inst->regs_written() > 1) {
split_grf[inst->dst.reg] = false;
}
}
/* Allocate new space for split regs. Note that the virtual
* numbers will be contiguous.
*/
for (int i = 0; i < num_vars; i++) {
if (split_grf[i]) {
new_virtual_grf[i] = virtual_grf_alloc(1);
for (int j = 2; j < this->virtual_grf_sizes[i]; j++) {
int reg = virtual_grf_alloc(1);
assert(reg == new_virtual_grf[i] + j - 1);
(void) reg;
}
this->virtual_grf_sizes[i] = 1;
}
}
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
if (inst->dst.file == GRF &&
split_grf[inst->dst.reg] &&
inst->dst.reg_offset != 0) {
inst->dst.reg = (new_virtual_grf[inst->dst.reg] +
inst->dst.reg_offset - 1);
inst->dst.reg_offset = 0;
}
for (int i = 0; i < 3; i++) {
if (inst->src[i].file == GRF &&
split_grf[inst->src[i].reg] &&
inst->src[i].reg_offset != 0) {
inst->src[i].reg = (new_virtual_grf[inst->src[i].reg] +
inst->src[i].reg_offset - 1);
inst->src[i].reg_offset = 0;
}
}
}
this->live_intervals_valid = false;
}
bool
fs_visitor::remove_dead_constants()
{
if (c->dispatch_width == 8) {
this->params_remap = ralloc_array(mem_ctx, int, c->prog_data.nr_params);
for (unsigned int i = 0; i < c->prog_data.nr_params; i++)
this->params_remap[i] = -1;
/* Find which params are still in use. */
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
for (int i = 0; i < 3; i++) {
int constant_nr = inst->src[i].reg + inst->src[i].reg_offset;
if (inst->src[i].file != UNIFORM)
continue;
assert(constant_nr < (int)c->prog_data.nr_params);
/* For now, set this to non-negative. We'll give it the
* actual new number in a moment, in order to keep the
* register numbers nicely ordered.
*/
this->params_remap[constant_nr] = 0;
}
}
/* Figure out what the new numbers for the params will be. At some
* point when we're doing uniform array access, we're going to want
* to keep the distinction between .reg and .reg_offset, but for
* now we don't care.
*/
unsigned int new_nr_params = 0;
for (unsigned int i = 0; i < c->prog_data.nr_params; i++) {
if (this->params_remap[i] != -1) {
this->params_remap[i] = new_nr_params++;
}
}
/* Update the list of params to be uploaded to match our new numbering. */
for (unsigned int i = 0; i < c->prog_data.nr_params; i++) {
int remapped = this->params_remap[i];
if (remapped == -1)
continue;
/* We've already done setup_paramvalues_refs() so no need to worry
* about param_index and param_offset.
*/
c->prog_data.param[remapped] = c->prog_data.param[i];
}
c->prog_data.nr_params = new_nr_params;
} else {
/* This should have been generated in the 8-wide pass already. */
assert(this->params_remap);
}
/* Now do the renumbering of the shader to remove unused params. */
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
for (int i = 0; i < 3; i++) {
int constant_nr = inst->src[i].reg + inst->src[i].reg_offset;
if (inst->src[i].file != UNIFORM)
continue;
assert(this->params_remap[constant_nr] != -1);
inst->src[i].reg = this->params_remap[constant_nr];
inst->src[i].reg_offset = 0;
}
}
return true;
}
/**
* Choose accesses from the UNIFORM file to demote to using the pull
* constant buffer.
*
* We allow a fragment shader to have more than the specified minimum
* maximum number of fragment shader uniform components (64). If
* there are too many of these, they'd fill up all of register space.
* So, this will push some of them out to the pull constant buffer and
* update the program to load them.
*/
void
fs_visitor::setup_pull_constants()
{
/* Only allow 16 registers (128 uniform components) as push constants. */
unsigned int max_uniform_components = 16 * 8;
if (c->prog_data.nr_params <= max_uniform_components)
return;
if (c->dispatch_width == 16) {
fail("Pull constants not supported in 16-wide\n");
return;
}
/* Just demote the end of the list. We could probably do better
* here, demoting things that are rarely used in the program first.
*/
int pull_uniform_base = max_uniform_components;
int pull_uniform_count = c->prog_data.nr_params - pull_uniform_base;
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
for (int i = 0; i < 3; i++) {
if (inst->src[i].file != UNIFORM)
continue;
int uniform_nr = inst->src[i].reg + inst->src[i].reg_offset;
if (uniform_nr < pull_uniform_base)
continue;
fs_reg dst = fs_reg(this, glsl_type::float_type);
fs_reg index = fs_reg((unsigned)SURF_INDEX_FRAG_CONST_BUFFER);
fs_reg offset = fs_reg((unsigned)(((uniform_nr -
pull_uniform_base) * 4) & ~15));
fs_inst *pull = new(mem_ctx) fs_inst(FS_OPCODE_PULL_CONSTANT_LOAD,
dst, index, offset);
pull->ir = inst->ir;
pull->annotation = inst->annotation;
pull->base_mrf = 14;
pull->mlen = 1;
inst->insert_before(pull);
inst->src[i].file = GRF;
inst->src[i].reg = dst.reg;
inst->src[i].reg_offset = 0;
inst->src[i].smear = (uniform_nr - pull_uniform_base) & 3;
}
}
for (int i = 0; i < pull_uniform_count; i++) {
c->prog_data.pull_param[i] = c->prog_data.param[pull_uniform_base + i];
}
c->prog_data.nr_params -= pull_uniform_count;
c->prog_data.nr_pull_params = pull_uniform_count;
}
/**
* Attempts to move immediate constants into the immediate
* constant slot of following instructions.
*
* Immediate constants are a bit tricky -- they have to be in the last
* operand slot, you can't do abs/negate on them,
*/
bool
fs_visitor::propagate_constants()
{
bool progress = false;
calculate_live_intervals();
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
if (inst->opcode != BRW_OPCODE_MOV ||
inst->predicated ||
inst->dst.file != GRF || inst->src[0].file != IMM ||
inst->dst.type != inst->src[0].type ||
(c->dispatch_width == 16 &&
(inst->force_uncompressed || inst->force_sechalf)))
continue;
/* Don't bother with cases where we should have had the
* operation on the constant folded in GLSL already.
*/
if (inst->saturate)
continue;
/* Found a move of a constant to a GRF. Find anything else using the GRF
* before it's written, and replace it with the constant if we can.
*/
for (fs_inst *scan_inst = (fs_inst *)inst->next;
!scan_inst->is_tail_sentinel();
scan_inst = (fs_inst *)scan_inst->next) {
if (scan_inst->opcode == BRW_OPCODE_DO ||
scan_inst->opcode == BRW_OPCODE_WHILE ||
scan_inst->opcode == BRW_OPCODE_ELSE ||
scan_inst->opcode == BRW_OPCODE_ENDIF) {
break;
}
for (int i = 2; i >= 0; i--) {
if (scan_inst->src[i].file != GRF ||
scan_inst->src[i].reg != inst->dst.reg ||
scan_inst->src[i].reg_offset != inst->dst.reg_offset)
continue;
/* Don't bother with cases where we should have had the
* operation on the constant folded in GLSL already.
*/
if (scan_inst->src[i].negate || scan_inst->src[i].abs)
continue;
switch (scan_inst->opcode) {
case BRW_OPCODE_MOV:
scan_inst->src[i] = inst->src[0];
progress = true;
break;
case BRW_OPCODE_MUL:
case BRW_OPCODE_ADD:
if (i == 1) {
scan_inst->src[i] = inst->src[0];
progress = true;
} else if (i == 0 && scan_inst->src[1].file != IMM) {
/* Fit this constant in by commuting the operands.
* Exception: we can't do this for 32-bit integer MUL
* because it's asymmetric.
*/
if (scan_inst->opcode == BRW_OPCODE_MUL &&
(scan_inst->src[1].type == BRW_REGISTER_TYPE_D ||
scan_inst->src[1].type == BRW_REGISTER_TYPE_UD))
break;
scan_inst->src[0] = scan_inst->src[1];
scan_inst->src[1] = inst->src[0];
progress = true;
}
break;
case BRW_OPCODE_CMP:
case BRW_OPCODE_IF:
if (i == 1) {
scan_inst->src[i] = inst->src[0];
progress = true;
} else if (i == 0 && scan_inst->src[1].file != IMM) {
uint32_t new_cmod;
new_cmod = brw_swap_cmod(scan_inst->conditional_mod);
if (new_cmod != ~0u) {
/* Fit this constant in by swapping the operands and
* flipping the test
*/
scan_inst->src[0] = scan_inst->src[1];
scan_inst->src[1] = inst->src[0];
scan_inst->conditional_mod = new_cmod;
progress = true;
}
}
break;
case BRW_OPCODE_SEL:
if (i == 1) {
scan_inst->src[i] = inst->src[0];
progress = true;
} else if (i == 0 && scan_inst->src[1].file != IMM) {
scan_inst->src[0] = scan_inst->src[1];
scan_inst->src[1] = inst->src[0];
/* If this was predicated, flipping operands means
* we also need to flip the predicate.
*/
if (scan_inst->conditional_mod == BRW_CONDITIONAL_NONE) {
scan_inst->predicate_inverse =
!scan_inst->predicate_inverse;
}
progress = true;
}
break;
case SHADER_OPCODE_RCP:
/* The hardware doesn't do math on immediate values
* (because why are you doing that, seriously?), but
* the correct answer is to just constant fold it
* anyway.
*/
assert(i == 0);
if (inst->src[0].imm.f != 0.0f) {
scan_inst->opcode = BRW_OPCODE_MOV;
scan_inst->src[0] = inst->src[0];
scan_inst->src[0].imm.f = 1.0f / scan_inst->src[0].imm.f;
progress = true;
}
break;
case FS_OPCODE_PULL_CONSTANT_LOAD:
scan_inst->src[i] = inst->src[0];
progress = true;
break;
default:
break;
}
}
if (scan_inst->dst.file == GRF &&
scan_inst->overwrites_reg(inst->dst)) {
break;
}
}
}
if (progress)
this->live_intervals_valid = false;
return progress;
}
/**
* Attempts to move immediate constants into the immediate
* constant slot of following instructions.
*
* Immediate constants are a bit tricky -- they have to be in the last
* operand slot, you can't do abs/negate on them,
*/
bool
fs_visitor::opt_algebraic()
{
bool progress = false;
calculate_live_intervals();
foreach_list(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
switch (inst->opcode) {
case BRW_OPCODE_MUL:
if (inst->src[1].file != IMM)
continue;
/* a * 1.0 = a */
if (inst->src[1].type == BRW_REGISTER_TYPE_F &&
inst->src[1].imm.f == 1.0) {
inst->opcode = BRW_OPCODE_MOV;
inst->src[1] = reg_undef;
progress = true;
break;
}
break;
default:
break;
}
}
return progress;
}
/**
* Must be called after calculate_live_intervales() to remove unused
* writes to registers -- register allocation will fail otherwise
* because something deffed but not used won't be considered to
* interfere with other regs.
*/
bool
fs_visitor::dead_code_eliminate()
{
bool progress = false;
int pc = 0;
calculate_live_intervals();
foreach_list_safe(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
if (inst->dst.file == GRF && this->virtual_grf_use[inst->dst.reg] <= pc) {
inst->remove();
progress = true;
}
pc++;
}
if (progress)
live_intervals_valid = false;
return progress;
}
/**
* Implements a second type of register coalescing: This one checks if
* the two regs involved in a raw move don't interfere, in which case
* they can both by stored in the same place and the MOV removed.
*/
bool
fs_visitor::register_coalesce_2()
{
bool progress = false;
calculate_live_intervals();
foreach_list_safe(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
if (inst->opcode != BRW_OPCODE_MOV ||
inst->predicated ||
inst->saturate ||
inst->src[0].file != GRF ||
inst->src[0].negate ||
inst->src[0].abs ||
inst->src[0].smear != -1 ||
inst->dst.file != GRF ||
inst->dst.type != inst->src[0].type ||
virtual_grf_sizes[inst->src[0].reg] != 1 ||
virtual_grf_interferes(inst->dst.reg, inst->src[0].reg)) {
continue;
}
int reg_from = inst->src[0].reg;
assert(inst->src[0].reg_offset == 0);
int reg_to = inst->dst.reg;
int reg_to_offset = inst->dst.reg_offset;
foreach_list_safe(node, &this->instructions) {
fs_inst *scan_inst = (fs_inst *)node;
if (scan_inst->dst.file == GRF &&
scan_inst->dst.reg == reg_from) {
scan_inst->dst.reg = reg_to;
scan_inst->dst.reg_offset = reg_to_offset;
}
for (int i = 0; i < 3; i++) {
if (scan_inst->src[i].file == GRF &&
scan_inst->src[i].reg == reg_from) {
scan_inst->src[i].reg = reg_to;
scan_inst->src[i].reg_offset = reg_to_offset;
}
}
}
inst->remove();
live_intervals_valid = false;
progress = true;
continue;
}
return progress;
}
bool
fs_visitor::register_coalesce()
{
bool progress = false;
int if_depth = 0;
int loop_depth = 0;
foreach_list_safe(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
/* Make sure that we dominate the instructions we're going to
* scan for interfering with our coalescing, or we won't have
* scanned enough to see if anything interferes with our
* coalescing. We don't dominate the following instructions if
* we're in a loop or an if block.
*/
switch (inst->opcode) {
case BRW_OPCODE_DO:
loop_depth++;
break;
case BRW_OPCODE_WHILE:
loop_depth--;
break;
case BRW_OPCODE_IF:
if_depth++;
break;
case BRW_OPCODE_ENDIF:
if_depth--;
break;
default:
break;
}
if (loop_depth || if_depth)
continue;
if (inst->opcode != BRW_OPCODE_MOV ||
inst->predicated ||
inst->saturate ||
inst->dst.file != GRF || (inst->src[0].file != GRF &&
inst->src[0].file != UNIFORM)||
inst->dst.type != inst->src[0].type)
continue;
bool has_source_modifiers = inst->src[0].abs || inst->src[0].negate;
/* Found a move of a GRF to a GRF. Let's see if we can coalesce
* them: check for no writes to either one until the exit of the
* program.
*/
bool interfered = false;
for (fs_inst *scan_inst = (fs_inst *)inst->next;
!scan_inst->is_tail_sentinel();
scan_inst = (fs_inst *)scan_inst->next) {
if (scan_inst->dst.file == GRF) {
if (scan_inst->overwrites_reg(inst->dst) ||
scan_inst->overwrites_reg(inst->src[0])) {
interfered = true;
break;
}
}
/* The gen6 MATH instruction can't handle source modifiers or
* unusual register regions, so avoid coalescing those for
* now. We should do something more specific.
*/
if (intel->gen >= 6 &&
scan_inst->is_math() &&
(has_source_modifiers || inst->src[0].file == UNIFORM)) {
interfered = true;
break;
}
/* The accumulator result appears to get used for the
* conditional modifier generation. When negating a UD
* value, there is a 33rd bit generated for the sign in the
* accumulator value, so now you can't check, for example,
* equality with a 32-bit value. See piglit fs-op-neg-uint.
*/
if (scan_inst->conditional_mod &&
inst->src[0].negate &&
inst->src[0].type == BRW_REGISTER_TYPE_UD) {
interfered = true;
break;
}
}
if (interfered) {
continue;
}
/* Rewrite the later usage to point at the source of the move to
* be removed.
*/
for (fs_inst *scan_inst = inst;
!scan_inst->is_tail_sentinel();
scan_inst = (fs_inst *)scan_inst->next) {
for (int i = 0; i < 3; i++) {
if (scan_inst->src[i].file == GRF &&
scan_inst->src[i].reg == inst->dst.reg &&
scan_inst->src[i].reg_offset == inst->dst.reg_offset) {
fs_reg new_src = inst->src[0];
if (scan_inst->src[i].abs) {
new_src.negate = 0;
new_src.abs = 1;
}
new_src.negate ^= scan_inst->src[i].negate;
scan_inst->src[i] = new_src;
}
}
}
inst->remove();
progress = true;
}
if (progress)
live_intervals_valid = false;
return progress;
}
bool
fs_visitor::compute_to_mrf()
{
bool progress = false;
int next_ip = 0;
calculate_live_intervals();
foreach_list_safe(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
int ip = next_ip;
next_ip++;
if (inst->opcode != BRW_OPCODE_MOV ||
inst->predicated ||
inst->dst.file != MRF || inst->src[0].file != GRF ||
inst->dst.type != inst->src[0].type ||
inst->src[0].abs || inst->src[0].negate || inst->src[0].smear != -1)
continue;
/* Work out which hardware MRF registers are written by this
* instruction.
*/
int mrf_low = inst->dst.reg & ~BRW_MRF_COMPR4;
int mrf_high;
if (inst->dst.reg & BRW_MRF_COMPR4) {
mrf_high = mrf_low + 4;
} else if (c->dispatch_width == 16 &&
(!inst->force_uncompressed && !inst->force_sechalf)) {
mrf_high = mrf_low + 1;
} else {
mrf_high = mrf_low;
}
/* Can't compute-to-MRF this GRF if someone else was going to
* read it later.
*/
if (this->virtual_grf_use[inst->src[0].reg] > ip)
continue;
/* Found a move of a GRF to a MRF. Let's see if we can go
* rewrite the thing that made this GRF to write into the MRF.
*/
fs_inst *scan_inst;
for (scan_inst = (fs_inst *)inst->prev;
scan_inst->prev != NULL;
scan_inst = (fs_inst *)scan_inst->prev) {
if (scan_inst->dst.file == GRF &&
scan_inst->dst.reg == inst->src[0].reg) {
/* Found the last thing to write our reg we want to turn
* into a compute-to-MRF.
*/
/* SENDs can only write to GRFs, so no compute-to-MRF. */
if (scan_inst->mlen) {
break;
}
/* If it's predicated, it (probably) didn't populate all
* the channels. 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->predicated)
break;
/* If it's half of register setup and not the same half as
* our MOV we're trying to remove, bail for now.
*/
if (scan_inst->force_uncompressed != inst->force_uncompressed ||
scan_inst->force_sechalf != inst->force_sechalf) {
break;
}
/* SEND instructions can't have MRF as a destination. */
if (scan_inst->mlen)
break;
if (intel->gen >= 6) {
/* gen6 math instructions must have the destination be
* GRF, so no compute-to-MRF for them.
*/
if (scan_inst->is_math()) {
break;
}
}
if (scan_inst->dst.reg_offset == inst->src[0].reg_offset) {
/* Found the creator of our MRF's source value. */
scan_inst->dst.file = MRF;
scan_inst->dst.reg = inst->dst.reg;
scan_inst->saturate |= inst->saturate;
inst->remove();
progress = true;
}
break;
}
/* We don't handle flow control here. Most computation of
* values that end up in MRFs are shortly before the MRF
* write anyway.
*/
if (scan_inst->opcode == BRW_OPCODE_DO ||
scan_inst->opcode == BRW_OPCODE_WHILE ||
scan_inst->opcode == BRW_OPCODE_ELSE ||
scan_inst->opcode == BRW_OPCODE_ENDIF) {
break;
}
/* You can't read from an MRF, so if someone else reads our
* MRF's source GRF that we wanted to rewrite, that stops us.
*/
bool interfered = false;
for (int i = 0; i < 3; i++) {
if (scan_inst->src[i].file == GRF &&
scan_inst->src[i].reg == inst->src[0].reg &&
scan_inst->src[i].reg_offset == inst->src[0].reg_offset) {
interfered = true;
}
}
if (interfered)
break;
if (scan_inst->dst.file == MRF) {
/* If somebody else writes our MRF here, we can't
* compute-to-MRF before that.
*/
int scan_mrf_low = scan_inst->dst.reg & ~BRW_MRF_COMPR4;
int scan_mrf_high;
if (scan_inst->dst.reg & BRW_MRF_COMPR4) {
scan_mrf_high = scan_mrf_low + 4;
} else if (c->dispatch_width == 16 &&
(!scan_inst->force_uncompressed &&
!scan_inst->force_sechalf)) {
scan_mrf_high = scan_mrf_low + 1;
} else {
scan_mrf_high = scan_mrf_low;
}
if (mrf_low == scan_mrf_low ||
mrf_low == scan_mrf_high ||
mrf_high == scan_mrf_low ||
mrf_high == scan_mrf_high) {
break;
}
}
if (scan_inst->mlen > 0) {
/* Found a SEND instruction, which means that there are
* live values in MRFs from base_mrf to base_mrf +
* scan_inst->mlen - 1. Don't go pushing our MRF write up
* above it.
*/
if (mrf_low >= scan_inst->base_mrf &&
mrf_low < scan_inst->base_mrf + scan_inst->mlen) {
break;
}
if (mrf_high >= scan_inst->base_mrf &&
mrf_high < scan_inst->base_mrf + scan_inst->mlen) {
break;
}
}
}
}
if (progress)
live_intervals_valid = false;
return progress;
}
/**
* Walks through basic blocks, looking for repeated MRF writes and
* removing the later ones.
*/
bool
fs_visitor::remove_duplicate_mrf_writes()
{
fs_inst *last_mrf_move[16];
bool progress = false;
/* Need to update the MRF tracking for compressed instructions. */
if (c->dispatch_width == 16)
return false;
memset(last_mrf_move, 0, sizeof(last_mrf_move));
foreach_list_safe(node, &this->instructions) {
fs_inst *inst = (fs_inst *)node;
switch (inst->opcode) {
case BRW_OPCODE_DO:
case BRW_OPCODE_WHILE:
case BRW_OPCODE_IF:
case BRW_OPCODE_ELSE:
case BRW_OPCODE_ENDIF:
memset(last_mrf_move, 0, sizeof(last_mrf_move));
continue;
default:
break;
}
if (inst->opcode == BRW_OPCODE_MOV &&
inst->dst.file == MRF) {
fs_inst *prev_inst = last_mrf_move[inst->dst.reg];
if (prev_inst && inst->equals(prev_inst)) {
inst->remove();
progress = true;
continue;
}
}
/* Clear out the last-write records for MRFs that were overwritten. */
if (inst->dst.file == MRF) {
last_mrf_move[inst->dst.reg] = NULL;
}
if (inst->mlen > 0) {
/* Found a SEND instruction, which will include two or fewer
* implied MRF writes. We could do better here.
*/
for (int i = 0; i < implied_mrf_writes(inst); i++) {
last_mrf_move[inst->base_mrf + i] = NULL;
}
}
/* Clear out any MRF move records whose sources got overwritten. */
if (inst->dst.file == GRF) {
for (unsigned int i = 0; i < Elements(last_mrf_move); i++) {
if (last_mrf_move[i] &&
last_mrf_move[i]->src[0].reg == inst->dst.reg) {
last_mrf_move[i] = NULL;
}
}
}
if (inst->opcode == BRW_OPCODE_MOV &&
inst->dst.file == MRF &&
inst->src[0].file == GRF &&
!inst->predicated) {
last_mrf_move[inst->dst.reg] = inst;
}
}
if (progress)
live_intervals_valid = false;
return progress;
}
/**
* Possibly returns an instruction that set up @param reg.
*
* Sometimes we want to take the result of some expression/variable
* dereference tree and rewrite the instruction generating the result
* of the tree. When processing the tree, we know that the
* instructions generated are all writing temporaries that are dead
* outside of this tree. So, if we have some instructions that write
* a temporary, we're free to point that temp write somewhere else.
*
* Note that this doesn't guarantee that the instruction generated
* only reg -- it might be the size=4 destination of a texture instruction.
*/
fs_inst *
fs_visitor::get_instruction_generating_reg(fs_inst *start,
fs_inst *end,
fs_reg reg)
{
if (end == start ||
end->predicated ||
end->force_uncompressed ||
end->force_sechalf ||
!reg.equals(end->dst)) {
return NULL;
} else {
return end;
}
}
bool
fs_visitor::run()
{
uint32_t prog_offset_16 = 0;
uint32_t orig_nr_params = c->prog_data.nr_params;
brw_wm_payload_setup(brw, c);
if (c->dispatch_width == 16) {
/* align to 64 byte boundary. */
while ((c->func.nr_insn * sizeof(struct brw_instruction)) % 64) {
brw_NOP(p);
}
/* Save off the start of this 16-wide program in case we succeed. */
prog_offset_16 = c->func.nr_insn * sizeof(struct brw_instruction);
brw_set_compression_control(p, BRW_COMPRESSION_COMPRESSED);
}
if (0) {
emit_dummy_fs();
} else {
calculate_urb_setup();
if (intel->gen < 6)
emit_interpolation_setup_gen4();
else
emit_interpolation_setup_gen6();
/* Generate FS IR for main(). (the visitor only descends into
* functions called "main").
*/
foreach_list(node, &*shader->ir) {
ir_instruction *ir = (ir_instruction *)node;
base_ir = ir;
this->result = reg_undef;
ir->accept(this);
}
if (failed)
return false;
emit_fb_writes();
split_virtual_grfs();
setup_paramvalues_refs();
setup_pull_constants();
bool progress;
do {
progress = false;
progress = remove_duplicate_mrf_writes() || progress;
progress = propagate_constants() || progress;
progress = opt_algebraic() || progress;
progress = opt_cse() || progress;
progress = opt_copy_propagate() || progress;
progress = register_coalesce() || progress;
progress = register_coalesce_2() || progress;
progress = compute_to_mrf() || progress;
progress = dead_code_eliminate() || progress;
} while (progress);
remove_dead_constants();
schedule_instructions();
assign_curb_setup();
assign_urb_setup();
if (0) {
/* Debug of register spilling: Go spill everything. */
for (int i = 0; i < virtual_grf_count; i++) {
spill_reg(i);
}
}
if (0)
assign_regs_trivial();
else {
while (!assign_regs()) {
if (failed)
break;
}
}
}
assert(force_uncompressed_stack == 0);
assert(force_sechalf_stack == 0);
if (failed)
return false;
generate_code();
if (c->dispatch_width == 8) {
c->prog_data.reg_blocks = brw_register_blocks(grf_used);
} else {
c->prog_data.reg_blocks_16 = brw_register_blocks(grf_used);
c->prog_data.prog_offset_16 = prog_offset_16;
/* Make sure we didn't try to sneak in an extra uniform */
assert(orig_nr_params == c->prog_data.nr_params);
(void) orig_nr_params;
}
return !failed;
}
bool
brw_wm_fs_emit(struct brw_context *brw, struct brw_wm_compile *c,
struct gl_shader_program *prog)
{
struct intel_context *intel = &brw->intel;
bool start_busy = false;
float start_time = 0;
if (!prog)
return false;
if (unlikely(INTEL_DEBUG & DEBUG_PERF)) {
start_busy = (intel->batch.last_bo &&
drm_intel_bo_busy(intel->batch.last_bo));
start_time = get_time();
}
struct brw_shader *shader =
(brw_shader *) prog->_LinkedShaders[MESA_SHADER_FRAGMENT];
if (!shader)
return false;
if (unlikely(INTEL_DEBUG & DEBUG_WM)) {
printf("GLSL IR for native fragment shader %d:\n", prog->Name);
_mesa_print_ir(shader->ir, NULL);
printf("\n\n");
}
/* Now the main event: Visit the shader IR and generate our FS IR for it.
*/
c->dispatch_width = 8;
fs_visitor v(c, prog, shader);
if (!v.run()) {
prog->LinkStatus = false;
ralloc_strcat(&prog->InfoLog, v.fail_msg);
_mesa_problem(NULL, "Failed to compile fragment shader: %s\n",
v.fail_msg);
return false;
}
if (intel->gen >= 5 && c->prog_data.nr_pull_params == 0) {
c->dispatch_width = 16;
fs_visitor v2(c, prog, shader);
v2.import_uniforms(&v);
if (!v2.run()) {
perf_debug("16-wide shader failed to compile, falling back to "
"8-wide at a 10-20%% performance cost: %s", v2.fail_msg);
}
}
c->prog_data.dispatch_width = 8;
if (unlikely(INTEL_DEBUG & DEBUG_PERF)) {
if (shader->compiled_once)
brw_wm_debug_recompile(brw, prog, &c->key);
shader->compiled_once = true;
if (start_busy && !drm_intel_bo_busy(intel->batch.last_bo)) {
perf_debug("FS compile took %.03f ms and stalled the GPU\n",
(get_time() - start_time) * 1000);
}
}
return true;
}
bool
brw_fs_precompile(struct gl_context *ctx, struct gl_shader_program *prog)
{
struct brw_context *brw = brw_context(ctx);
struct intel_context *intel = &brw->intel;
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 (intel->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 (prog->Name != 0)
key.proj_attrib_mask = 0xffffffff;
if (intel->gen < 6)
key.vp_outputs_written |= BITFIELD64_BIT(FRAG_ATTRIB_WPOS);
for (int i = 0; i < FRAG_ATTRIB_MAX; i++) {
if (!(fp->Base.InputsRead & BITFIELD64_BIT(i)))
continue;
if (prog->Name == 0)
key.proj_attrib_mask |= 1 << i;
if (intel->gen < 6) {
int vp_index = _mesa_vert_result_to_frag_attrib((gl_vert_result) i);
if (vp_index >= 0)
key.vp_outputs_written |= BITFIELD64_BIT(vp_index);
}
}
key.clamp_fragment_color = true;
for (int i = 0; i < MAX_SAMPLERS; i++) {
if (fp->Base.ShadowSamplers & (1 << i)) {
/* Assume DEPTH_TEXTURE_MODE is the default: X, X, X, 1 */
key.tex.swizzles[i] =
MAKE_SWIZZLE4(SWIZZLE_X, SWIZZLE_X, SWIZZLE_X, SWIZZLE_ONE);
} else {
/* Color sampler: assume no swizzling. */
key.tex.swizzles[i] = SWIZZLE_XYZW;
}
}
if (fp->Base.InputsRead & FRAG_BIT_WPOS) {
key.drawable_height = ctx->DrawBuffer->Height;
}
if ((fp->Base.InputsRead & FRAG_BIT_WPOS) || program_uses_dfdy) {
key.render_to_fbo = _mesa_is_user_fbo(ctx->DrawBuffer);
}
key.nr_color_regions = 1;
key.program_string_id = bfp->id;
uint32_t old_prog_offset = brw->wm.prog_offset;
struct brw_wm_prog_data *old_prog_data = brw->wm.prog_data;
bool success = do_wm_prog(brw, prog, bfp, &key);
brw->wm.prog_offset = old_prog_offset;
brw->wm.prog_data = old_prog_data;
return success;
}