glsl: Remove unused lower_variable_index_to_cond_assign.

It's been replaced by nir_lower_indirect_derefs().

Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8044>
This commit is contained in:
Emma Anholt
2022-04-12 10:46:42 -07:00
committed by Marge Bot
parent 2529690ee3
commit dd3179aff0
5 changed files with 1 additions and 466 deletions

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@@ -127,9 +127,6 @@ bool do_vec_index_to_swizzle(exec_list *instructions);
bool lower_discard(exec_list *instructions);
void lower_discard_flow(exec_list *instructions);
bool lower_instructions(exec_list *instructions, unsigned what_to_lower);
bool lower_variable_index_to_cond_assign(gl_shader_stage stage,
exec_list *instructions, bool lower_input, bool lower_output,
bool lower_temp, bool lower_uniform);
bool lower_quadop_vector(exec_list *instructions);
bool lower_const_arrays_to_uniforms(exec_list *instructions, unsigned stage, unsigned max_uniform_components);
bool lower_clip_cull_distance(struct gl_shader_program *prog,

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@@ -110,7 +110,7 @@ public:
* Unrolling the loop may convert that access into constant-indexing.
*
* Many drivers don't support particular kinds of variable indexing,
* and have to resort to using lower_variable_index_to_cond_assign to
* and have to resort to using nir_lower_indirect_derefs to
* handle it. This results in huge amounts of horrible code, so we'd
* like to avoid that if possible. Here, we just note that it will
* happen.

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@@ -1,455 +0,0 @@
/*
* Copyright © 2010 Luca Barbieri
*
* 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_variable_index_to_cond_assign.cpp
*
* Turns non-constant indexing into array types to a series of
* conditional moves of each element into a temporary.
*
* Pre-DX10 GPUs often don't have a native way to do this operation,
* and this works around that.
*
* The lowering process proceeds as follows. Each non-constant index
* found in an r-value is converted to a canonical form \c array[i]. Each
* element of the array is conditionally assigned to a temporary by comparing
* \c i to a constant index. This is done by cloning the canonical form and
* replacing all occurances of \c i with a constant. Each remaining occurance
* of the canonical form in the IR is replaced with a dereference of the
* temporary variable.
*
* L-values with non-constant indices are handled similarly. In this case,
* the RHS of the assignment is assigned to a temporary. The non-constant
* index is replace with the canonical form (just like for r-values). The
* temporary is conditionally assigned to each element of the canonical form
* by comparing \c i with each index. The same clone-and-replace scheme is
* used.
*/
#include "ir.h"
#include "ir_rvalue_visitor.h"
#include "ir_optimization.h"
#include "compiler/glsl_types.h"
#include "main/macros.h"
#include "program/prog_instruction.h" /* For SWIZZLE_XXXX */
#include "ir_builder.h"
using namespace ir_builder;
static inline bool
is_array_or_matrix(const ir_rvalue *ir)
{
return (ir->type->is_array() || ir->type->is_matrix());
}
namespace {
/**
* Replace a dereference of a variable with a specified r-value
*
* Each time a dereference of the specified value is replaced, the r-value
* tree is cloned.
*/
class deref_replacer : public ir_rvalue_visitor {
public:
deref_replacer(const ir_variable *variable_to_replace, ir_rvalue *value)
: variable_to_replace(variable_to_replace), value(value),
progress(false)
{
assert(this->variable_to_replace != NULL);
assert(this->value != NULL);
}
virtual void handle_rvalue(ir_rvalue **rvalue)
{
ir_dereference_variable *const dv = (*rvalue)->as_dereference_variable();
if (dv != NULL && dv->var == this->variable_to_replace) {
this->progress = true;
*rvalue = this->value->clone(ralloc_parent(*rvalue), NULL);
}
}
const ir_variable *variable_to_replace;
ir_rvalue *value;
bool progress;
};
/**
* Find a variable index dereference of an array in an rvalue tree
*/
class find_variable_index : public ir_hierarchical_visitor {
public:
find_variable_index()
: deref(NULL)
{
/* empty */
}
virtual ir_visitor_status visit_enter(ir_dereference_array *ir)
{
if (is_array_or_matrix(ir->array) &&
ir->array_index->as_constant() == NULL) {
this->deref = ir;
return visit_stop;
}
return visit_continue;
}
/**
* First array dereference found in the tree that has a non-constant index.
*/
ir_dereference_array *deref;
};
struct assignment_generator
{
ir_instruction* base_ir;
ir_dereference *rvalue;
ir_variable *old_index;
bool is_write;
unsigned int write_mask;
ir_variable* var;
assignment_generator()
: base_ir(NULL),
rvalue(NULL),
old_index(NULL),
is_write(false),
write_mask(0),
var(NULL)
{
}
void generate(unsigned i, ir_factory &body) const
{
/* Clone the old r-value in its entirety. Then replace any occurances of
* the old variable index with the new constant index.
*/
ir_dereference *element = this->rvalue->clone(body.mem_ctx, NULL);
ir_constant *const index = body.constant(i);
deref_replacer r(this->old_index, index);
element->accept(&r);
assert(r.progress);
ir_assignment *const assignment = (is_write)
? assign(element, this->var, write_mask)
: assign(this->var, element);
body.emit(assignment);
}
};
struct switch_generator
{
/* make TFunction a template parameter if you need to use other generators */
typedef assignment_generator TFunction;
const TFunction& generator;
ir_variable* index;
void *mem_ctx;
switch_generator(const TFunction& generator, ir_variable *index)
: generator(generator), index(index)
{
this->mem_ctx = ralloc_parent(index);
}
void bisect(unsigned begin, unsigned end, ir_factory &body)
{
unsigned middle = (begin + end) >> 1;
assert(index->type->is_integer_32());
ir_constant *const middle_c = (index->type->base_type == GLSL_TYPE_UINT)
? new(body.mem_ctx) ir_constant((unsigned)middle)
: new(body.mem_ctx) ir_constant((int)middle);
ir_if *if_less = new(body.mem_ctx) ir_if(less(this->index, middle_c));
ir_factory then_body(&if_less->then_instructions, body.mem_ctx);
ir_factory else_body(&if_less->else_instructions, body.mem_ctx);
generate(begin, middle, then_body);
generate(middle, end, else_body);
body.emit(if_less);
}
void generate(unsigned begin, unsigned end, ir_factory &body)
{
if (begin == end)
return;
unsigned length = end - begin;
if (length == 1)
generator.generate(begin, body);
else
bisect(begin, end, body);
}
};
/**
* Visitor class for replacing expressions with ir_constant values.
*/
class variable_index_to_cond_assign_visitor : public ir_rvalue_visitor {
public:
variable_index_to_cond_assign_visitor(gl_shader_stage stage,
bool lower_input,
bool lower_output,
bool lower_temp,
bool lower_uniform)
: progress(false), stage(stage), lower_inputs(lower_input),
lower_outputs(lower_output), lower_temps(lower_temp),
lower_uniforms(lower_uniform)
{
/* empty */
}
bool progress;
gl_shader_stage stage;
bool lower_inputs;
bool lower_outputs;
bool lower_temps;
bool lower_uniforms;
bool storage_type_needs_lowering(ir_dereference_array *deref) const
{
/* If a variable isn't eventually the target of this dereference, then
* it must be a constant or some sort of anonymous temporary storage.
*
* FINISHME: Is this correct? Most drivers treat arrays of constants as
* FINISHME: uniforms. It seems like this should do the same.
*/
const ir_variable *const var = deref->array->variable_referenced();
if (var == NULL)
return this->lower_temps;
switch (var->data.mode) {
case ir_var_auto:
case ir_var_temporary:
return this->lower_temps;
case ir_var_uniform:
case ir_var_shader_storage:
return this->lower_uniforms;
case ir_var_shader_shared:
return false;
case ir_var_function_in:
case ir_var_const_in:
return this->lower_temps;
case ir_var_system_value:
/* There are only a few system values that have array types:
*
* gl_TessLevelInner[]
* gl_TessLevelOuter[]
* gl_SampleMaskIn[]
*
* The tessellation factor arrays are lowered to vec4/vec2s
* by lower_tess_level() before this pass occurs, so we'll
* never see them here.
*
* The only remaining case is gl_SampleMaskIn[], which has
* a length of ceil(ctx->Const.MaxSamples / 32). Most hardware
* supports no more than 32 samples, in which case our lowering
* produces a single read of gl_SampleMaskIn[0]. Even with 64x
* MSAA, the array length is only 2, so the lowering is fairly
* efficient. Therefore, lower unconditionally.
*/
return true;
case ir_var_shader_in:
/* The input array size is unknown at compiler time for non-patch
* inputs in TCS and TES. The arrays are sized to
* the implementation-dependent limit "gl_MaxPatchVertices", but
* the real size is stored in the "gl_PatchVerticesIn" built-in
* uniform.
*
* The TCS input array size is specified by
* glPatchParameteri(GL_PATCH_VERTICES).
*
* The TES input array size is specified by the "vertices" output
* layout qualifier in TCS.
*/
if ((stage == MESA_SHADER_TESS_CTRL ||
stage == MESA_SHADER_TESS_EVAL) && !var->data.patch)
return false;
return this->lower_inputs;
case ir_var_function_out:
/* TCS non-patch outputs can only be indexed with "gl_InvocationID".
* Other expressions are not allowed.
*/
if (stage == MESA_SHADER_TESS_CTRL && !var->data.patch)
return false;
return this->lower_temps;
case ir_var_shader_out:
return this->lower_outputs;
case ir_var_function_inout:
return this->lower_temps;
}
assert(!"Should not get here.");
return false;
}
bool needs_lowering(ir_dereference_array *deref) const
{
if (deref == NULL || deref->array_index->as_constant() ||
!is_array_or_matrix(deref->array))
return false;
return this->storage_type_needs_lowering(deref);
}
ir_variable *convert_dereference_array(ir_dereference_array *orig_deref,
ir_assignment* orig_assign,
ir_dereference *orig_base)
{
void *const mem_ctx = ralloc_parent(base_ir);
exec_list list;
ir_factory body(&list, mem_ctx);
assert(is_array_or_matrix(orig_deref->array));
const unsigned length = (orig_deref->array->type->is_array())
? orig_deref->array->type->length
: orig_deref->array->type->matrix_columns;
/* Temporary storage for either the result of the dereference of
* the array, or the RHS that's being assigned into the
* dereference of the array.
*/
ir_variable *var;
if (orig_assign) {
var = body.make_temp(orig_assign->rhs->type,
"dereference_array_value");
body.emit(assign(var, orig_assign->rhs));
} else {
var = body.make_temp(orig_deref->type,
"dereference_array_value");
}
/* Store the index to a temporary to avoid reusing its tree. */
ir_variable *index = body.make_temp(orig_deref->array_index->type,
"dereference_array_index");
body.emit(assign(index, orig_deref->array_index));
orig_deref->array_index = deref(index).val;
assignment_generator ag;
ag.rvalue = orig_base;
ag.base_ir = base_ir;
ag.old_index = index;
ag.var = var;
if (orig_assign) {
ag.is_write = true;
ag.write_mask = orig_assign->write_mask;
} else {
ag.is_write = false;
}
switch_generator sg(ag, index);
sg.generate(0, length, body);
base_ir->insert_before(&list);
return var;
}
virtual void handle_rvalue(ir_rvalue **pir)
{
if (this->in_assignee)
return;
if (!*pir)
return;
ir_dereference_array* orig_deref = (*pir)->as_dereference_array();
if (needs_lowering(orig_deref)) {
ir_variable *var =
convert_dereference_array(orig_deref, NULL, orig_deref);
assert(var);
*pir = new(ralloc_parent(base_ir)) ir_dereference_variable(var);
this->progress = true;
}
}
ir_visitor_status
visit_leave(ir_assignment *ir)
{
ir_rvalue_visitor::visit_leave(ir);
find_variable_index f;
ir->lhs->accept(&f);
if (f.deref != NULL && storage_type_needs_lowering(f.deref)) {
convert_dereference_array(f.deref, ir, ir->lhs);
ir->remove();
this->progress = true;
}
return visit_continue;
}
};
} /* anonymous namespace */
bool
lower_variable_index_to_cond_assign(gl_shader_stage stage,
exec_list *instructions,
bool lower_input,
bool lower_output,
bool lower_temp,
bool lower_uniform)
{
variable_index_to_cond_assign_visitor v(stage,
lower_input,
lower_output,
lower_temp,
lower_uniform);
/* Continue lowering until no progress is made. If there are multiple
* levels of indirection (e.g., non-constant indexing of array elements and
* matrix columns of an array of matrix), each pass will only lower one
* level of indirection.
*/
bool progress_ever = false;
do {
v.progress = false;
visit_list_elements(&v, instructions);
progress_ever = v.progress || progress_ever;
} while (v.progress);
return progress_ever;
}

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@@ -172,7 +172,6 @@ files_libglsl = files(
'lower_precision.cpp',
'lower_subroutine.cpp',
'lower_tess_level.cpp',
'lower_variable_index_to_cond_assign.cpp',
'lower_vec_index_to_cond_assign.cpp',
'lower_vec_index_to_swizzle.cpp',
'lower_vector.cpp',

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@@ -110,12 +110,6 @@ do_optimization(struct exec_list *ir, const char *optimization,
} else if (sscanf(optimization, "lower_instructions ( %d ) ",
&int_0) == 1) {
return lower_instructions(ir, int_0);
} else if (sscanf(optimization, "lower_variable_index_to_cond_assign "
"( %d , %d , %d , %d ) ", &int_0, &int_1, &int_2,
&int_3) == 4) {
return lower_variable_index_to_cond_assign(MESA_SHADER_VERTEX, ir,
int_0 != 0, int_1 != 0,
int_2 != 0, int_3 != 0);
} else if (sscanf(optimization, "lower_quadop_vector") == 1) {
return lower_quadop_vector(ir);
} else {