/*
* 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 opt_algebraic.cpp
*
* Takes advantage of association, commutivity, and other algebraic
* properties to simplify expressions.
*/
#include "ir.h"
#include "ir_visitor.h"
#include "ir_rvalue_visitor.h"
#include "ir_optimization.h"
#include "ir_builder.h"
#include "glsl_types.h"
using namespace ir_builder;
namespace {
/**
* Visitor class for replacing expressions with ir_constant values.
*/
class ir_algebraic_visitor : public ir_rvalue_visitor {
public:
ir_algebraic_visitor(bool native_integers,
const struct gl_shader_compiler_options *options)
: options(options)
{
this->progress = false;
this->mem_ctx = NULL;
this->native_integers = native_integers;
}
virtual ~ir_algebraic_visitor()
{
}
ir_rvalue *handle_expression(ir_expression *ir);
void handle_rvalue(ir_rvalue **rvalue);
bool reassociate_constant(ir_expression *ir1,
int const_index,
ir_constant *constant,
ir_expression *ir2);
void reassociate_operands(ir_expression *ir1,
int op1,
ir_expression *ir2,
int op2);
ir_rvalue *swizzle_if_required(ir_expression *expr,
ir_rvalue *operand);
const struct gl_shader_compiler_options *options;
void *mem_ctx;
bool native_integers;
bool progress;
};
} /* unnamed namespace */
static inline bool
is_vec_zero(ir_constant *ir)
{
return (ir == NULL) ? false : ir->is_zero();
}
static inline bool
is_vec_one(ir_constant *ir)
{
return (ir == NULL) ? false : ir->is_one();
}
static inline bool
is_vec_two(ir_constant *ir)
{
return (ir == NULL) ? false : ir->is_value(2.0, 2);
}
static inline bool
is_vec_four(ir_constant *ir)
{
return (ir == NULL) ? false : ir->is_value(4.0, 4);
}
static inline bool
is_vec_negative_one(ir_constant *ir)
{
return (ir == NULL) ? false : ir->is_negative_one();
}
static inline bool
is_valid_vec_const(ir_constant *ir)
{
if (ir == NULL)
return false;
if (!ir->type->is_scalar() && !ir->type->is_vector())
return false;
return true;
}
static inline bool
is_less_than_one(ir_constant *ir)
{
assert(ir->type->base_type == GLSL_TYPE_FLOAT);
if (!is_valid_vec_const(ir))
return false;
unsigned component = 0;
for (int c = 0; c < ir->type->vector_elements; c++) {
if (ir->get_float_component(c) < 1.0f)
component++;
}
return (component == ir->type->vector_elements);
}
static inline bool
is_greater_than_zero(ir_constant *ir)
{
assert(ir->type->base_type == GLSL_TYPE_FLOAT);
if (!is_valid_vec_const(ir))
return false;
unsigned component = 0;
for (int c = 0; c < ir->type->vector_elements; c++) {
if (ir->get_float_component(c) > 0.0f)
component++;
}
return (component == ir->type->vector_elements);
}
static void
update_type(ir_expression *ir)
{
if (ir->operands[0]->type->is_vector())
ir->type = ir->operands[0]->type;
else
ir->type = ir->operands[1]->type;
}
/* Recognize (v.x + v.y) + (v.z + v.w) as dot(v, 1.0) */
static ir_expression *
try_replace_with_dot(ir_expression *expr0, ir_expression *expr1, void *mem_ctx)
{
if (expr0 && expr0->operation == ir_binop_add &&
expr0->type->is_float() &&
expr1 && expr1->operation == ir_binop_add &&
expr1->type->is_float()) {
ir_swizzle *x = expr0->operands[0]->as_swizzle();
ir_swizzle *y = expr0->operands[1]->as_swizzle();
ir_swizzle *z = expr1->operands[0]->as_swizzle();
ir_swizzle *w = expr1->operands[1]->as_swizzle();
if (!x || x->mask.num_components != 1 ||
!y || y->mask.num_components != 1 ||
!z || z->mask.num_components != 1 ||
!w || w->mask.num_components != 1) {
return NULL;
}
bool swiz_seen[4] = {false, false, false, false};
swiz_seen[x->mask.x] = true;
swiz_seen[y->mask.x] = true;
swiz_seen[z->mask.x] = true;
swiz_seen[w->mask.x] = true;
if (!swiz_seen[0] || !swiz_seen[1] ||
!swiz_seen[2] || !swiz_seen[3]) {
return NULL;
}
if (x->val->equals(y->val) &&
x->val->equals(z->val) &&
x->val->equals(w->val)) {
return dot(x->val, new(mem_ctx) ir_constant(1.0f, 4));
}
}
return NULL;
}
void
ir_algebraic_visitor::reassociate_operands(ir_expression *ir1,
int op1,
ir_expression *ir2,
int op2)
{
ir_rvalue *temp = ir2->operands[op2];
ir2->operands[op2] = ir1->operands[op1];
ir1->operands[op1] = temp;
/* Update the type of ir2. The type of ir1 won't have changed --
* base types matched, and at least one of the operands of the 2
* binops is still a vector if any of them were.
*/
update_type(ir2);
this->progress = true;
}
/**
* Reassociates a constant down a tree of adds or multiplies.
*
* Consider (2 * (a * (b * 0.5))). We want to send up with a * b.
*/
bool
ir_algebraic_visitor::reassociate_constant(ir_expression *ir1, int const_index,
ir_constant *constant,
ir_expression *ir2)
{
if (!ir2 || ir1->operation != ir2->operation)
return false;
/* Don't want to even think about matrices. */
if (ir1->operands[0]->type->is_matrix() ||
ir1->operands[1]->type->is_matrix() ||
ir2->operands[0]->type->is_matrix() ||
ir2->operands[1]->type->is_matrix())
return false;
ir_constant *ir2_const[2];
ir2_const[0] = ir2->operands[0]->constant_expression_value();
ir2_const[1] = ir2->operands[1]->constant_expression_value();
if (ir2_const[0] && ir2_const[1])
return false;
if (ir2_const[0]) {
reassociate_operands(ir1, const_index, ir2, 1);
return true;
} else if (ir2_const[1]) {
reassociate_operands(ir1, const_index, ir2, 0);
return true;
}
if (reassociate_constant(ir1, const_index, constant,
ir2->operands[0]->as_expression())) {
update_type(ir2);
return true;
}
if (reassociate_constant(ir1, const_index, constant,
ir2->operands[1]->as_expression())) {
update_type(ir2);
return true;
}
return false;
}
/* When eliminating an expression and just returning one of its operands,
* we may need to swizzle that operand out to a vector if the expression was
* vector type.
*/
ir_rvalue *
ir_algebraic_visitor::swizzle_if_required(ir_expression *expr,
ir_rvalue *operand)
{
if (expr->type->is_vector() && operand->type->is_scalar()) {
return new(mem_ctx) ir_swizzle(operand, 0, 0, 0, 0,
expr->type->vector_elements);
} else
return operand;
}
ir_rvalue *
ir_algebraic_visitor::handle_expression(ir_expression *ir)
{
ir_constant *op_const[4] = {NULL, NULL, NULL, NULL};
ir_expression *op_expr[4] = {NULL, NULL, NULL, NULL};
unsigned int i;
if (ir->operation == ir_binop_mul &&
ir->operands[0]->type->is_matrix() &&
ir->operands[1]->type->is_vector()) {
ir_expression *matrix_mul = ir->operands[0]->as_expression();
if (matrix_mul && matrix_mul->operation == ir_binop_mul &&
matrix_mul->operands[0]->type->is_matrix() &&
matrix_mul->operands[1]->type->is_matrix()) {
return mul(matrix_mul->operands[0],
mul(matrix_mul->operands[1], ir->operands[1]));
}
}
assert(ir->get_num_operands() <= 4);
for (i = 0; i < ir->get_num_operands(); i++) {
if (ir->operands[i]->type->is_matrix())
return ir;
op_const[i] = ir->operands[i]->constant_expression_value();
op_expr[i] = ir->operands[i]->as_expression();
}
if (this->mem_ctx == NULL)
this->mem_ctx = ralloc_parent(ir);
switch (ir->operation) {
case ir_unop_bit_not:
if (op_expr[0] && op_expr[0]->operation == ir_unop_bit_not)
return op_expr[0]->operands[0];
break;
case ir_unop_abs:
if (op_expr[0] == NULL)
break;
switch (op_expr[0]->operation) {
case ir_unop_abs:
case ir_unop_neg:
return abs(op_expr[0]->operands[0]);
default:
break;
}
break;
case ir_unop_neg:
if (op_expr[0] == NULL)
break;
if (op_expr[0]->operation == ir_unop_neg) {
return op_expr[0]->operands[0];
}
break;
case ir_unop_exp:
if (op_expr[0] == NULL)
break;
if (op_expr[0]->operation == ir_unop_log) {
return op_expr[0]->operands[0];
}
break;
case ir_unop_log:
if (op_expr[0] == NULL)
break;
if (op_expr[0]->operation == ir_unop_exp) {
return op_expr[0]->operands[0];
}
break;
case ir_unop_exp2:
if (op_expr[0] == NULL)
break;
if (op_expr[0]->operation == ir_unop_log2) {
return op_expr[0]->operands[0];
}
if (!options->EmitNoPow && op_expr[0]->operation == ir_binop_mul) {
for (int log2_pos = 0; log2_pos < 2; log2_pos++) {
ir_expression *log2_expr =
op_expr[0]->operands[log2_pos]->as_expression();
if (log2_expr && log2_expr->operation == ir_unop_log2) {
return new(mem_ctx) ir_expression(ir_binop_pow,
ir->type,
log2_expr->operands[0],
op_expr[0]->operands[1 - log2_pos]);
}
}
}
break;
case ir_unop_log2:
if (op_expr[0] == NULL)
break;
if (op_expr[0]->operation == ir_unop_exp2) {
return op_expr[0]->operands[0];
}
break;
case ir_unop_f2i:
case ir_unop_f2u:
if (op_expr[0] && op_expr[0]->operation == ir_unop_trunc) {
return new(mem_ctx) ir_expression(ir->operation,
ir->type,
op_expr[0]->operands[0]);
}
break;
case ir_unop_logic_not: {
enum ir_expression_operation new_op = ir_unop_logic_not;
if (op_expr[0] == NULL)
break;
switch (op_expr[0]->operation) {
case ir_binop_less: new_op = ir_binop_gequal; break;
case ir_binop_greater: new_op = ir_binop_lequal; break;
case ir_binop_lequal: new_op = ir_binop_greater; break;
case ir_binop_gequal: new_op = ir_binop_less; break;
case ir_binop_equal: new_op = ir_binop_nequal; break;
case ir_binop_nequal: new_op = ir_binop_equal; break;
case ir_binop_all_equal: new_op = ir_binop_any_nequal; break;
case ir_binop_any_nequal: new_op = ir_binop_all_equal; break;
default:
/* The default case handler is here to silence a warning from GCC.
*/
break;
}
if (new_op != ir_unop_logic_not) {
return new(mem_ctx) ir_expression(new_op,
ir->type,
op_expr[0]->operands[0],
op_expr[0]->operands[1]);
}
break;
}
case ir_unop_saturate:
if (op_expr[0] && op_expr[0]->operation == ir_binop_add) {
ir_expression *b2f_0 = op_expr[0]->operands[0]->as_expression();
ir_expression *b2f_1 = op_expr[0]->operands[1]->as_expression();
if (b2f_0 && b2f_0->operation == ir_unop_b2f &&
b2f_1 && b2f_1->operation == ir_unop_b2f) {
return b2f(logic_or(b2f_0->operands[0], b2f_1->operands[0]));
}
}
break;
case ir_binop_add:
if (is_vec_zero(op_const[0]))
return ir->operands[1];
if (is_vec_zero(op_const[1]))
return ir->operands[0];
/* Reassociate addition of constants so that we can do constant
* folding.
*/
if (op_const[0] && !op_const[1])
reassociate_constant(ir, 0, op_const[0], op_expr[1]);
if (op_const[1] && !op_const[0])
reassociate_constant(ir, 1, op_const[1], op_expr[0]);
/* Recognize (v.x + v.y) + (v.z + v.w) as dot(v, 1.0) */
if (options->OptimizeForAOS) {
ir_expression *expr = try_replace_with_dot(op_expr[0], op_expr[1],
mem_ctx);
if (expr)
return expr;
}
/* Replace (-x + y) * a + x and commutative variations with lrp(x, y, a).
*
* (-x + y) * a + x
* (x * -a) + (y * a) + x
* x + (x * -a) + (y * a)
* x * (1 - a) + y * a
* lrp(x, y, a)
*/
for (int mul_pos = 0; mul_pos < 2; mul_pos++) {
ir_expression *mul = op_expr[mul_pos];
if (!mul || mul->operation != ir_binop_mul)
continue;
/* Multiply found on one of the operands. Now check for an
* inner addition operation.
*/
for (int inner_add_pos = 0; inner_add_pos < 2; inner_add_pos++) {
ir_expression *inner_add =
mul->operands[inner_add_pos]->as_expression();
if (!inner_add || inner_add->operation != ir_binop_add)
continue;
/* Inner addition found on one of the operands. Now check for
* one of the operands of the inner addition to be the negative
* of x_operand.
*/
for (int neg_pos = 0; neg_pos < 2; neg_pos++) {
ir_expression *neg =
inner_add->operands[neg_pos]->as_expression();
if (!neg || neg->operation != ir_unop_neg)
continue;
ir_rvalue *x_operand = ir->operands[1 - mul_pos];
if (!neg->operands[0]->equals(x_operand))
continue;
ir_rvalue *y_operand = inner_add->operands[1 - neg_pos];
ir_rvalue *a_operand = mul->operands[1 - inner_add_pos];
if (x_operand->type != y_operand->type ||
x_operand->type != a_operand->type)
continue;
return lrp(x_operand, y_operand, a_operand);
}
}
}
break;
case ir_binop_sub:
if (is_vec_zero(op_const[0]))
return neg(ir->operands[1]);
if (is_vec_zero(op_const[1]))
return ir->operands[0];
break;
case ir_binop_mul:
if (is_vec_one(op_const[0]))
return ir->operands[1];
if (is_vec_one(op_const[1]))
return ir->operands[0];
if (is_vec_zero(op_const[0]) || is_vec_zero(op_const[1]))
return ir_constant::zero(ir, ir->type);
if (is_vec_negative_one(op_const[0]))
return neg(ir->operands[1]);
if (is_vec_negative_one(op_const[1]))
return neg(ir->operands[0]);
if (op_expr[0] && op_expr[0]->operation == ir_unop_b2f &&
op_expr[1] && op_expr[1]->operation == ir_unop_b2f) {
return b2f(logic_and(op_expr[0]->operands[0], op_expr[1]->operands[0]));
}
/* Reassociate multiplication of constants so that we can do
* constant folding.
*/
if (op_const[0] && !op_const[1])
reassociate_constant(ir, 0, op_const[0], op_expr[1]);
if (op_const[1] && !op_const[0])
reassociate_constant(ir, 1, op_const[1], op_expr[0]);
/* Optimizes
*
* (mul (floor (add (abs x) 0.5) (sign x)))
*
* into
*
* (trunc (add x (mul (sign x) 0.5)))
*/
for (int i = 0; i < 2; i++) {
ir_expression *sign_expr = ir->operands[i]->as_expression();
ir_expression *floor_expr = ir->operands[1 - i]->as_expression();
if (!sign_expr || sign_expr->operation != ir_unop_sign ||
!floor_expr || floor_expr->operation != ir_unop_floor)
continue;
ir_expression *add_expr = floor_expr->operands[0]->as_expression();
if (!add_expr)
continue;
for (int j = 0; j < 2; j++) {
ir_expression *abs_expr = add_expr->operands[j]->as_expression();
if (!abs_expr || abs_expr->operation != ir_unop_abs)
continue;
ir_constant *point_five = add_expr->operands[1 - j]->as_constant();
if (!point_five->is_value(0.5, 0))
continue;
if (abs_expr->operands[0]->equals(sign_expr->operands[0])) {
return trunc(add(abs_expr->operands[0],
mul(sign_expr, point_five)));
}
}
}
break;
case ir_binop_div:
if (is_vec_one(op_const[0]) && (
ir->type->base_type == GLSL_TYPE_FLOAT ||
ir->type->base_type == GLSL_TYPE_DOUBLE)) {
return new(mem_ctx) ir_expression(ir_unop_rcp,
ir->operands[1]->type,
ir->operands[1],
NULL);
}
if (is_vec_one(op_const[1]))
return ir->operands[0];
break;
case ir_binop_dot:
if (is_vec_zero(op_const[0]) || is_vec_zero(op_const[1]))
return ir_constant::zero(mem_ctx, ir->type);
for (int i = 0; i < 2; i++) {
if (!op_const[i])
continue;
unsigned components[4] = { 0 }, count = 0;
for (unsigned c = 0; c < op_const[i]->type->vector_elements; c++) {
if (op_const[i]->is_zero())
continue;
components[count] = c;
count++;
}
/* No channels had zero values; bail. */
if (count >= op_const[i]->type->vector_elements)
break;
ir_expression_operation op = count == 1 ?
ir_binop_mul : ir_binop_dot;
/* Swizzle both operands to remove the channels that were zero. */
return new(mem_ctx)
ir_expression(op, ir->type,
new(mem_ctx) ir_swizzle(ir->operands[0],
components, count),
new(mem_ctx) ir_swizzle(ir->operands[1],
components, count));
}
break;
case ir_binop_less:
case ir_binop_lequal:
case ir_binop_greater:
case ir_binop_gequal:
case ir_binop_equal:
case ir_binop_nequal:
for (int add_pos = 0; add_pos < 2; add_pos++) {
ir_expression *add = op_expr[add_pos];
if (!add || add->operation != ir_binop_add)
continue;
ir_constant *zero = op_const[1 - add_pos];
if (!is_vec_zero(zero))
continue;
/* Depending of the zero position we want to optimize
* (0 cmp x+y) into (-x cmp y) or (x+y cmp 0) into (x cmp -y)
*/
if (add_pos == 1) {
return new(mem_ctx) ir_expression(ir->operation,
neg(add->operands[0]),
add->operands[1]);
} else {
return new(mem_ctx) ir_expression(ir->operation,
add->operands[0],
neg(add->operands[1]));
}
}
break;
case ir_binop_all_equal:
case ir_binop_any_nequal:
if (ir->operands[0]->type->is_scalar() &&
ir->operands[1]->type->is_scalar())
return new(mem_ctx) ir_expression(ir->operation == ir_binop_all_equal
? ir_binop_equal : ir_binop_nequal,
ir->operands[0],
ir->operands[1]);
break;
case ir_binop_rshift:
case ir_binop_lshift:
/* 0 >> x == 0 */
if (is_vec_zero(op_const[0]))
return ir->operands[0];
/* x >> 0 == x */
if (is_vec_zero(op_const[1]))
return ir->operands[0];
break;
case ir_binop_logic_and:
if (is_vec_one(op_const[0])) {
return ir->operands[1];
} else if (is_vec_one(op_const[1])) {
return ir->operands[0];
} else if (is_vec_zero(op_const[0]) || is_vec_zero(op_const[1])) {
return ir_constant::zero(mem_ctx, ir->type);
} else if (op_expr[0] && op_expr[0]->operation == ir_unop_logic_not &&
op_expr[1] && op_expr[1]->operation == ir_unop_logic_not) {
/* De Morgan's Law:
* (not A) and (not B) === not (A or B)
*/
return logic_not(logic_or(op_expr[0]->operands[0],
op_expr[1]->operands[0]));
} else if (ir->operands[0]->equals(ir->operands[1])) {
/* (a && a) == a */
return ir->operands[0];
}
break;
case ir_binop_logic_xor:
if (is_vec_zero(op_const[0])) {
return ir->operands[1];
} else if (is_vec_zero(op_const[1])) {
return ir->operands[0];
} else if (is_vec_one(op_const[0])) {
return logic_not(ir->operands[1]);
} else if (is_vec_one(op_const[1])) {
return logic_not(ir->operands[0]);
} else if (ir->operands[0]->equals(ir->operands[1])) {
/* (a ^^ a) == false */
return ir_constant::zero(mem_ctx, ir->type);
}
break;
case ir_binop_logic_or:
if (is_vec_zero(op_const[0])) {
return ir->operands[1];
} else if (is_vec_zero(op_const[1])) {
return ir->operands[0];
} else if (is_vec_one(op_const[0]) || is_vec_one(op_const[1])) {
ir_constant_data data;
for (unsigned i = 0; i < 16; i++)
data.b[i] = true;
return new(mem_ctx) ir_constant(ir->type, &data);
} else if (op_expr[0] && op_expr[0]->operation == ir_unop_logic_not &&
op_expr[1] && op_expr[1]->operation == ir_unop_logic_not) {
/* De Morgan's Law:
* (not A) or (not B) === not (A and B)
*/
return logic_not(logic_and(op_expr[0]->operands[0],
op_expr[1]->operands[0]));
} else if (ir->operands[0]->equals(ir->operands[1])) {
/* (a || a) == a */
return ir->operands[0];
}
break;
case ir_binop_pow:
/* 1^x == 1 */
if (is_vec_one(op_const[0]))
return op_const[0];
/* x^1 == x */
if (is_vec_one(op_const[1]))
return ir->operands[0];
/* pow(2,x) == exp2(x) */
if (is_vec_two(op_const[0]))
return expr(ir_unop_exp2, ir->operands[1]);
if (is_vec_two(op_const[1])) {
ir_variable *x = new(ir) ir_variable(ir->operands[1]->type, "x",
ir_var_temporary);
base_ir->insert_before(x);
base_ir->insert_before(assign(x, ir->operands[0]));
return mul(x, x);
}
if (is_vec_four(op_const[1])) {
ir_variable *x = new(ir) ir_variable(ir->operands[1]->type, "x",
ir_var_temporary);
base_ir->insert_before(x);
base_ir->insert_before(assign(x, ir->operands[0]));
ir_variable *squared = new(ir) ir_variable(ir->operands[1]->type,
"squared",
ir_var_temporary);
base_ir->insert_before(squared);
base_ir->insert_before(assign(squared, mul(x, x)));
return mul(squared, squared);
}
break;
case ir_binop_min:
case ir_binop_max:
if (ir->type->base_type != GLSL_TYPE_FLOAT || options->EmitNoSat)
break;
/* Replace min(max) operations and its commutative combinations with
* a saturate operation
*/
for (int op = 0; op < 2; op++) {
ir_expression *inner_expr = op_expr[op];
ir_constant *outer_const = op_const[1 - op];
ir_expression_operation op_cond = (ir->operation == ir_binop_max) ?
ir_binop_min : ir_binop_max;
if (!inner_expr || !outer_const || (inner_expr->operation != op_cond))
continue;
/* One of these has to be a constant */
if (!inner_expr->operands[0]->as_constant() &&
!inner_expr->operands[1]->as_constant())
break;
/* Found a min(max) combination. Now try to see if its operands
* meet our conditions that we can do just a single saturate operation
*/
for (int minmax_op = 0; minmax_op < 2; minmax_op++) {
ir_rvalue *x = inner_expr->operands[minmax_op];
ir_rvalue *y = inner_expr->operands[1 - minmax_op];
ir_constant *inner_const = y->as_constant();
if (!inner_const)
continue;
/* min(max(x, 0.0), 1.0) is sat(x) */
if (ir->operation == ir_binop_min &&
inner_const->is_zero() &&
outer_const->is_one())
return saturate(x);
/* max(min(x, 1.0), 0.0) is sat(x) */
if (ir->operation == ir_binop_max &&
inner_const->is_one() &&
outer_const->is_zero())
return saturate(x);
/* min(max(x, 0.0), b) where b < 1.0 is sat(min(x, b)) */
if (ir->operation == ir_binop_min &&
inner_const->is_zero() &&
is_less_than_one(outer_const))
return saturate(expr(ir_binop_min, x, outer_const));
/* max(min(x, b), 0.0) where b < 1.0 is sat(min(x, b)) */
if (ir->operation == ir_binop_max &&
is_less_than_one(inner_const) &&
outer_const->is_zero())
return saturate(expr(ir_binop_min, x, inner_const));
/* max(min(x, 1.0), b) where b > 0.0 is sat(max(x, b)) */
if (ir->operation == ir_binop_max &&
inner_const->is_one() &&
is_greater_than_zero(outer_const))
return saturate(expr(ir_binop_max, x, outer_const));
/* min(max(x, b), 1.0) where b > 0.0 is sat(max(x, b)) */
if (ir->operation == ir_binop_min &&
is_greater_than_zero(inner_const) &&
outer_const->is_one())
return saturate(expr(ir_binop_max, x, inner_const));
}
}
break;
case ir_unop_rcp:
if (op_expr[0] && op_expr[0]->operation == ir_unop_rcp)
return op_expr[0]->operands[0];
if (op_expr[0] && (op_expr[0]->operation == ir_unop_exp2 ||
op_expr[0]->operation == ir_unop_exp)) {
return new(mem_ctx) ir_expression(op_expr[0]->operation, ir->type,
neg(op_expr[0]->operands[0]));
}
/* While ir_to_mesa.cpp will lower sqrt(x) to rcp(rsq(x)), it does so at
* its IR level, so we can always apply this transformation.
*/
if (op_expr[0] && op_expr[0]->operation == ir_unop_rsq)
return sqrt(op_expr[0]->operands[0]);
/* As far as we know, all backends are OK with rsq. */
if (op_expr[0] && op_expr[0]->operation == ir_unop_sqrt) {
return rsq(op_expr[0]->operands[0]);
}
break;
case ir_triop_fma:
/* Operands are op0 * op1 + op2. */
if (is_vec_zero(op_const[0]) || is_vec_zero(op_const[1])) {
return ir->operands[2];
} else if (is_vec_zero(op_const[2])) {
return mul(ir->operands[0], ir->operands[1]);
} else if (is_vec_one(op_const[0])) {
return add(ir->operands[1], ir->operands[2]);
} else if (is_vec_one(op_const[1])) {
return add(ir->operands[0], ir->operands[2]);
}
break;
case ir_triop_lrp:
/* Operands are (x, y, a). */
if (is_vec_zero(op_const[2])) {
return ir->operands[0];
} else if (is_vec_one(op_const[2])) {
return ir->operands[1];
} else if (ir->operands[0]->equals(ir->operands[1])) {
return ir->operands[0];
} else if (is_vec_zero(op_const[0])) {
return mul(ir->operands[1], ir->operands[2]);
} else if (is_vec_zero(op_const[1])) {
unsigned op2_components = ir->operands[2]->type->vector_elements;
ir_constant *one;
switch (ir->type->base_type) {
case GLSL_TYPE_FLOAT:
one = new(mem_ctx) ir_constant(1.0f, op2_components);
break;
case GLSL_TYPE_DOUBLE:
one = new(mem_ctx) ir_constant(1.0, op2_components);
break;
default:
one = NULL;
unreachable("unexpected type");
}
return mul(ir->operands[0], add(one, neg(ir->operands[2])));
}
break;
case ir_triop_csel:
if (is_vec_one(op_const[0]))
return ir->operands[1];
if (is_vec_zero(op_const[0]))
return ir->operands[2];
break;
default:
break;
}
return ir;
}
void
ir_algebraic_visitor::handle_rvalue(ir_rvalue **rvalue)
{
if (!*rvalue)
return;
ir_expression *expr = (*rvalue)->as_expression();
if (!expr || expr->operation == ir_quadop_vector)
return;
ir_rvalue *new_rvalue = handle_expression(expr);
if (new_rvalue == *rvalue)
return;
/* If the expr used to be some vec OP scalar returning a vector, and the
* optimization gave us back a scalar, we still need to turn it into a
* vector.
*/
*rvalue = swizzle_if_required(expr, new_rvalue);
this->progress = true;
}
bool
do_algebraic(exec_list *instructions, bool native_integers,
const struct gl_shader_compiler_options *options)
{
ir_algebraic_visitor v(native_integers, options);
visit_list_elements(&v, instructions);
return v.progress;
}