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glsl: Combine many instruction lowering passes into one.

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This should save on the overhead of tree-walking and provide a
convenient place to add more instruction lowering in the future.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
This commit is contained in:
Kenneth Graunke
2010-11-18 17:54:07 -08:00
committed by Ian Romanick
parent b943fb94bf
commit 63684a9ae7
11 changed files with 281 additions and 383 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
src/glsl/Makefile
View File

@@ -52,14 +52,11 @@ CXX_SOURCES = \
loop_analysis.cpp \
loop_controls.cpp \
loop_unroll.cpp \
lower_div_to_mul_rcp.cpp \
lower_explog_to_explog2.cpp \
lower_if_to_cond_assign.cpp \
lower_instructions.cpp \
lower_jumps.cpp \
lower_mat_op_to_vec.cpp \
lower_mod_to_fract.cpp \
lower_noise.cpp \
lower_sub_to_add_neg.cpp \
lower_texture_projection.cpp \
lower_variable_index_to_cond_assign.cpp \
lower_vec_index_to_cond_assign.cpp \

5
src/glsl/SConscript
View File

@@ -49,14 +49,11 @@ sources = [
'loop_analysis.cpp',
'loop_controls.cpp',
'loop_unroll.cpp',
'lower_div_to_mul_rcp.cpp',
'lower_explog_to_explog2.cpp',
'lower_if_to_cond_assign.cpp',
'lower_instructions.cpp',
'lower_jumps.cpp',
'lower_mat_op_to_vec.cpp',
'lower_mod_to_fract.cpp',
'lower_noise.cpp',
'lower_sub_to_add_neg.cpp',
'lower_variable_index_to_cond_assign.cpp',
'lower_vec_index_to_cond_assign.cpp',
'lower_vec_index_to_swizzle.cpp',

2
src/glsl/glsl_parser_extras.cpp
View File

@@ -708,7 +708,7 @@ do_common_optimization(exec_list *ir, bool linked, unsigned max_unroll_iteration
{
GLboolean progress = GL_FALSE;
progress = do_sub_to_add_neg(ir) || progress;
progress = lower_instructions(ir, SUB_TO_ADD_NEG) || progress;
if (linked) {
progress = do_function_inlining(ir) || progress;

10
src/glsl/ir_optimization.h
View File

@@ -28,6 +28,13 @@
* Prototypes for optimization passes to be called by the compiler and drivers.
*/
/* Operations for lower_instructions() */
#define SUB_TO_ADD_NEG 0x01
#define DIV_TO_MUL_RCP 0x02
#define EXP_TO_EXP2 0x04
#define LOG_TO_LOG2 0x08
#define MOD_TO_FRACT 0x10
bool do_common_optimization(exec_list *ir, bool linked, unsigned max_unroll_iterations);
bool do_algebraic(exec_list *instructions);
@@ -40,8 +47,6 @@ bool do_dead_code(exec_list *instructions);
bool do_dead_code_local(exec_list *instructions);
bool do_dead_code_unlinked(exec_list *instructions);
bool do_dead_functions(exec_list *instructions);
bool do_div_to_mul_rcp(exec_list *instructions);
bool do_explog_to_explog2(exec_list *instructions);
bool do_function_inlining(exec_list *instructions);
bool do_lower_jumps(exec_list *instructions, bool pull_out_jumps = true, bool lower_sub_return = true, bool lower_main_return = false, bool lower_continue = false, bool lower_break = false);
bool do_lower_texture_projection(exec_list *instructions);
@@ -56,6 +61,7 @@ bool do_swizzle_swizzle(exec_list *instructions);
bool do_tree_grafting(exec_list *instructions);
bool do_vec_index_to_cond_assign(exec_list *instructions);
bool do_vec_index_to_swizzle(exec_list *instructions);
bool lower_instructions(exec_list *instructions, unsigned what_to_lower);
bool lower_noise(exec_list *instructions);
bool lower_variable_index_to_cond_assign(exec_list *instructions,
bool lower_input, bool lower_output, bool lower_temp, bool lower_uniform);

114
src/glsl/lower_div_to_mul_rcp.cpp
View File

@@ -1,114 +0,0 @@
/*
* 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 lower_div_to_mul_rcp.cpp
*
* Breaks an ir_unop_div expression down to op0 * (rcp(op1)).
*
* Many GPUs don't have a divide instruction (945 and 965 included),
* but they do have an RCP instruction to compute an approximate
* reciprocal. By breaking the operation down, constant reciprocals
* can get constant folded.
*/
#include "ir.h"
#include "glsl_types.h"
class ir_div_to_mul_rcp_visitor : public ir_hierarchical_visitor {
public:
ir_div_to_mul_rcp_visitor()
{
this->made_progress = false;
}
ir_visitor_status visit_leave(ir_expression *);
bool made_progress;
};
bool
do_div_to_mul_rcp(exec_list *instructions)
{
ir_div_to_mul_rcp_visitor v;
visit_list_elements(&v, instructions);
return v.made_progress;
}
ir_visitor_status
ir_div_to_mul_rcp_visitor::visit_leave(ir_expression *ir)
{
if (ir->operation != ir_binop_div)
return visit_continue;
if (!ir->operands[1]->type->is_integer()) {
/* New expression for the 1.0 / op1 */
ir_rvalue *expr;
expr = new(ir) ir_expression(ir_unop_rcp,
ir->operands[1]->type,
ir->operands[1],
NULL);
/* op0 / op1 -> op0 * (1.0 / op1) */
ir->operation = ir_binop_mul;
ir->operands[1] = expr;
} else {
/* Be careful with integer division -- we need to do it as a
* float and re-truncate, since rcp(n > 1) of an integer would
* just be 0.
*/
ir_rvalue *op0, *op1;
const struct glsl_type *vec_type;
vec_type = glsl_type::get_instance(GLSL_TYPE_FLOAT,
ir->operands[1]->type->vector_elements,
ir->operands[1]->type->matrix_columns);
if (ir->operands[1]->type->base_type == GLSL_TYPE_INT)
op1 = new(ir) ir_expression(ir_unop_i2f, vec_type, ir->operands[1], NULL);
else
op1 = new(ir) ir_expression(ir_unop_u2f, vec_type, ir->operands[1], NULL);
op1 = new(ir) ir_expression(ir_unop_rcp, op1->type, op1, NULL);
vec_type = glsl_type::get_instance(GLSL_TYPE_FLOAT,
ir->operands[0]->type->vector_elements,
ir->operands[0]->type->matrix_columns);
if (ir->operands[0]->type->base_type == GLSL_TYPE_INT)
op0 = new(ir) ir_expression(ir_unop_i2f, vec_type, ir->operands[0], NULL);
else
op0 = new(ir) ir_expression(ir_unop_u2f, vec_type, ir->operands[0], NULL);
op0 = new(ir) ir_expression(ir_binop_mul, vec_type, op0, op1);
ir->operation = ir_unop_f2i;
ir->operands[0] = op0;
ir->operands[1] = NULL;
}
this->made_progress = true;
return visit_continue;
}

85
src/glsl/lower_explog_to_explog2.cpp
View File

@@ -1,85 +0,0 @@
/*
* 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 lower_explog_to_explog2.cpp
*
* Many GPUs don't have a base e log or exponent instruction, but they
* do have base 2 versions, so this pass converts exp and log to exp2
* and log2 operations.
*/
#include "main/core.h" /* for log2f on MSVC */
#include "ir.h"
#include "glsl_types.h"
class ir_explog_to_explog2_visitor : public ir_hierarchical_visitor {
public:
ir_explog_to_explog2_visitor()
{
this->progress = false;
}
ir_visitor_status visit_leave(ir_expression *);
bool progress;
};
bool
do_explog_to_explog2(exec_list *instructions)
{
ir_explog_to_explog2_visitor v;
visit_list_elements(&v, instructions);
return v.progress;
}
ir_visitor_status
ir_explog_to_explog2_visitor::visit_leave(ir_expression *ir)
{
if (ir->operation == ir_unop_exp) {
void *mem_ctx = talloc_parent(ir);
ir_constant *log2_e = new(mem_ctx) ir_constant(log2f(M_E));
ir->operation = ir_unop_exp2;
ir->operands[0] = new(mem_ctx) ir_expression(ir_binop_mul,
ir->operands[0]->type,
ir->operands[0],
log2_e);
this->progress = true;
}
if (ir->operation == ir_unop_log) {
void *mem_ctx = talloc_parent(ir);
ir->operation = ir_binop_mul;
ir->operands[0] = new(mem_ctx) ir_expression(ir_unop_log2,
ir->operands[0]->type,
ir->operands[0],
NULL);
ir->operands[1] = new(mem_ctx) ir_constant(1.0f / log2f(M_E));
this->progress = true;
}
return visit_continue;
}

262
src/glsl/lower_instructions.cpp Normal file
View File

@@ -0,0 +1,262 @@
/*
* 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 lower_instructions.cpp
*
* Many GPUs lack native instructions for certain expression operations, and
* must replace them with some other expression tree. This pass lowers some
* of the most common cases, allowing the lowering code to be implemented once
* rather than in each driver backend.
*
* Currently supported transformations:
* - SUB_TO_ADD_NEG
* - DIV_TO_MUL_RCP
* - EXP_TO_EXP2
* - LOG_TO_LOG2
* - MOD_TO_FRACT
*
* SUB_TO_ADD_NEG:
* ---------------
* Breaks an ir_binop_sub expression down to add(op0, neg(op1))
*
* This simplifies expression reassociation, and for many backends
* there is no subtract operation separate from adding the negation.
* For backends with native subtract operations, they will probably
* want to recognize add(op0, neg(op1)) or the other way around to
* produce a subtract anyway.
*
* DIV_TO_MUL_RCP:
* ---------------
* Breaks an ir_unop_div expression down to op0 * (rcp(op1)).
*
* Many GPUs don't have a divide instruction (945 and 965 included),
* but they do have an RCP instruction to compute an approximate
* reciprocal. By breaking the operation down, constant reciprocals
* can get constant folded.
*
* EXP_TO_EXP2 and LOG_TO_LOG2:
* ----------------------------
* Many GPUs don't have a base e log or exponent instruction, but they
* do have base 2 versions, so this pass converts exp and log to exp2
* and log2 operations.
*
* MOD_TO_FRACT:
* -------------
* Breaks an ir_unop_mod expression down to (op1 * fract(op0 / op1))
*
* Many GPUs don't have a MOD instruction (945 and 965 included), and
* if we have to break it down like this anyway, it gives an
* opportunity to do things like constant fold the (1.0 / op1) easily.
*/
#include "main/core.h" /* for M_E */
#include "glsl_types.h"
#include "ir.h"
#include "ir_optimization.h"
class lower_instructions_visitor : public ir_hierarchical_visitor {
public:
lower_instructions_visitor(unsigned lower)
: progress(false), lower(lower) { }
ir_visitor_status visit_leave(ir_expression *);
bool progress;
private:
unsigned lower; /** Bitfield of which operations to lower */
void sub_to_add_neg(ir_expression *);
void div_to_mul_rcp(ir_expression *);
void mod_to_fract(ir_expression *);
void exp_to_exp2(ir_expression *);
void log_to_log2(ir_expression *);
};
/**
* Determine if a particular type of lowering should occur
*/
#define lowering(x) (this->lower & x)
bool
lower_instructions(exec_list *instructions, unsigned what_to_lower)
{
lower_instructions_visitor v(what_to_lower);
visit_list_elements(&v, instructions);
return v.progress;
}
void
lower_instructions_visitor::sub_to_add_neg(ir_expression *ir)
{
ir->operation = ir_binop_add;
ir->operands[1] = new(ir) ir_expression(ir_unop_neg, ir->operands[1]->type,
ir->operands[1], NULL);
this->progress = true;
}
void
lower_instructions_visitor::div_to_mul_rcp(ir_expression *ir)
{
if (!ir->operands[1]->type->is_integer()) {
/* New expression for the 1.0 / op1 */
ir_rvalue *expr;
expr = new(ir) ir_expression(ir_unop_rcp,
ir->operands[1]->type,
ir->operands[1],
NULL);
/* op0 / op1 -> op0 * (1.0 / op1) */
ir->operation = ir_binop_mul;
ir->operands[1] = expr;
} else {
/* Be careful with integer division -- we need to do it as a
* float and re-truncate, since rcp(n > 1) of an integer would
* just be 0.
*/
ir_rvalue *op0, *op1;
const struct glsl_type *vec_type;
vec_type = glsl_type::get_instance(GLSL_TYPE_FLOAT,
ir->operands[1]->type->vector_elements,
ir->operands[1]->type->matrix_columns);
if (ir->operands[1]->type->base_type == GLSL_TYPE_INT)
op1 = new(ir) ir_expression(ir_unop_i2f, vec_type, ir->operands[1], NULL);
else
op1 = new(ir) ir_expression(ir_unop_u2f, vec_type, ir->operands[1], NULL);
op1 = new(ir) ir_expression(ir_unop_rcp, op1->type, op1, NULL);
vec_type = glsl_type::get_instance(GLSL_TYPE_FLOAT,
ir->operands[0]->type->vector_elements,
ir->operands[0]->type->matrix_columns);
if (ir->operands[0]->type->base_type == GLSL_TYPE_INT)
op0 = new(ir) ir_expression(ir_unop_i2f, vec_type, ir->operands[0], NULL);
else
op0 = new(ir) ir_expression(ir_unop_u2f, vec_type, ir->operands[0], NULL);
op0 = new(ir) ir_expression(ir_binop_mul, vec_type, op0, op1);
ir->operation = ir_unop_f2i;
ir->operands[0] = op0;
ir->operands[1] = NULL;
}
this->progress = true;
}
void
lower_instructions_visitor::exp_to_exp2(ir_expression *ir)
{
ir_constant *log2_e = new(ir) ir_constant(log2f(M_E));
ir->operation = ir_unop_exp2;
ir->operands[0] = new(ir) ir_expression(ir_binop_mul, ir->operands[0]->type,
ir->operands[0], log2_e);
this->progress = true;
}
void
lower_instructions_visitor::log_to_log2(ir_expression *ir)
{
ir->operation = ir_binop_mul;
ir->operands[0] = new(ir) ir_expression(ir_unop_log2, ir->operands[0]->type,
ir->operands[0], NULL);
ir->operands[1] = new(ir) ir_constant(1.0f / log2f(M_E));
this->progress = true;
}
void
lower_instructions_visitor::mod_to_fract(ir_expression *ir)
{
ir_variable *temp = new(ir) ir_variable(ir->operands[1]->type, "mod_b",
ir_var_temporary);
this->base_ir->insert_before(temp);
ir_assignment *const assign =
new(ir) ir_assignment(new(ir) ir_dereference_variable(temp),
ir->operands[1], NULL);
this->base_ir->insert_before(assign);
ir_expression *const div_expr =
new(ir) ir_expression(ir_binop_div, ir->operands[0]->type,
ir->operands[0],
new(ir) ir_dereference_variable(temp));
/* Don't generate new IR that would need to be lowered in an additional
* pass.
*/
if (lowering(DIV_TO_MUL_RCP))
div_to_mul_rcp(div_expr);
ir_rvalue *expr = new(ir) ir_expression(ir_unop_fract,
ir->operands[0]->type,
div_expr,
NULL);
ir->operation = ir_binop_mul;
ir->operands[0] = new(ir) ir_dereference_variable(temp);
ir->operands[1] = expr;
this->progress = true;
}
ir_visitor_status
lower_instructions_visitor::visit_leave(ir_expression *ir)
{
switch (ir->operation) {
case ir_binop_sub:
if (lowering(SUB_TO_ADD_NEG))
sub_to_add_neg(ir);
break;
case ir_binop_div:
if (lowering(DIV_TO_MUL_RCP))
div_to_mul_rcp(ir);
break;
case ir_unop_exp:
if (lowering(EXP_TO_EXP2))
exp_to_exp2(ir);
break;
case ir_unop_log:
if (lowering(LOG_TO_LOG2))
log_to_log2(ir);
break;
case ir_binop_mod:
if (lowering(MOD_TO_FRACT))
mod_to_fract(ir);
break;
default:
return visit_continue;
}
return visit_continue;
}

90
src/glsl/lower_mod_to_fract.cpp
View File

@@ -1,90 +0,0 @@
/*
* 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 lower_mod_to_fract.cpp
*
* Breaks an ir_unop_mod expression down to (op1 * fract(op0 / op1))
*
* Many GPUs don't have a MOD instruction (945 and 965 included), and
* if we have to break it down like this anyway, it gives an
* opportunity to do things like constant fold the (1.0 / op1) easily.
*/
#include "ir.h"
class ir_mod_to_fract_visitor : public ir_hierarchical_visitor {
public:
ir_mod_to_fract_visitor()
{
this->made_progress = false;
}
ir_visitor_status visit_leave(ir_expression *);
bool made_progress;
};
bool
do_mod_to_fract(exec_list *instructions)
{
ir_mod_to_fract_visitor v;
visit_list_elements(&v, instructions);
return v.made_progress;
}
ir_visitor_status
ir_mod_to_fract_visitor::visit_leave(ir_expression *ir)
{
if (ir->operation != ir_binop_mod)
return visit_continue;
ir_variable *temp = new(ir) ir_variable(ir->operands[1]->type, "mod_b",
ir_var_temporary);
this->base_ir->insert_before(temp);
ir_assignment *assign;
ir_rvalue *expr;
assign = new(ir) ir_assignment(new(ir) ir_dereference_variable(temp),
ir->operands[1], NULL);
this->base_ir->insert_before(assign);
expr = new(ir) ir_expression(ir_binop_div,
ir->operands[0]->type,
ir->operands[0],
new(ir) ir_dereference_variable(temp));
expr = new(ir) ir_expression(ir_unop_fract,
ir->operands[0]->type,
expr,
NULL);
ir->operation = ir_binop_mul;
ir->operands[0] = new(ir) ir_dereference_variable(temp);
ir->operands[1] = expr;
this->made_progress = true;
return visit_continue;
}

76
src/glsl/lower_sub_to_add_neg.cpp
View File

@@ -1,76 +0,0 @@
/*
* 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 lower_sub_to_add_neg.cpp
*
* Breaks an ir_binop_sub expression down to add(op0, neg(op1))
*
* This simplifies expression reassociation, and for many backends
* there is no subtract operation separate from adding the negation.
* For backends with native subtract operations, they will probably
* want to recognize add(op0, neg(op1)) or the other way around to
* produce a subtract anyway.
*/
#include "ir.h"
class ir_sub_to_add_neg_visitor : public ir_hierarchical_visitor {
public:
ir_sub_to_add_neg_visitor()
{
this->progress = false;
}
ir_visitor_status visit_leave(ir_expression *);
bool progress;
};
bool
do_sub_to_add_neg(exec_list *instructions)
{
ir_sub_to_add_neg_visitor v;
visit_list_elements(&v, instructions);
return v.progress;
}
ir_visitor_status
ir_sub_to_add_neg_visitor::visit_leave(ir_expression *ir)
{
if (ir->operation != ir_binop_sub)
return visit_continue;
void *mem_ctx = talloc_parent(ir);
ir->operation = ir_binop_add;
ir->operands[1] = new(mem_ctx) ir_expression(ir_unop_neg,
ir->operands[1]->type,
ir->operands[1],
NULL);
this->progress = true;
return visit_continue;
}

10
src/mesa/drivers/dri/i965/brw_fs.cpp
View File

@@ -101,10 +101,12 @@ brw_link_shader(struct gl_context *ctx, struct gl_shader_program *prog)
clone_ir_list(mem_ctx, shader->ir, shader->base.ir);
do_mat_op_to_vec(shader->ir);
do_mod_to_fract(shader->ir);
do_div_to_mul_rcp(shader->ir);
do_sub_to_add_neg(shader->ir);
do_explog_to_explog2(shader->ir);
lower_instructions(shader->ir,
MOD_TO_FRACT |
DIV_TO_MUL_RCP |
SUB_TO_ADD_NEG |
EXP_TO_EXP2 |
LOG_TO_LOG2);
do_lower_texture_projection(shader->ir);
brw_do_cubemap_normalize(shader->ir);

5
src/mesa/program/ir_to_mesa.cpp
View File

@@ -2798,9 +2798,8 @@ _mesa_ir_link_shader(struct gl_context *ctx, struct gl_shader_program *prog)
/* Lowering */
do_mat_op_to_vec(ir);
do_mod_to_fract(ir);
do_div_to_mul_rcp(ir);
do_explog_to_explog2(ir);
lower_instructions(ir, MOD_TO_FRACT | DIV_TO_MUL_RCP | EXP_TO_EXP2
| LOG_TO_LOG2);
progress = do_lower_jumps(ir, true, true, options->EmitNoMainReturn, options->EmitNoCont, options->EmitNoLoops) || progress;