mirror of https://gitlab.freedesktop.org/mesa/mesa
682 lines
25 KiB
C++
682 lines
25 KiB
C++
/*
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* Copyright © 2011 Intel Corporation
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the "Software"),
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* to deal in the Software without restriction, including without limitation
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* the rights to use, copy, modify, merge, publish, distribute, sublicense,
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* and/or sell copies of the Software, and to permit persons to whom the
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* Software is furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice (including the next
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* paragraph) shall be included in all copies or substantial portions of the
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* Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
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* DEALINGS IN THE SOFTWARE.
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*/
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/**
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* \file lower_varyings_to_packed.cpp
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*
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* This lowering pass generates GLSL code that manually packs varyings into
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* vec4 slots, for the benefit of back-ends that don't support packed varyings
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* natively.
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*
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* For example, the following shader:
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*
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* out mat3x2 foo; // location=4, location_frac=0
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* out vec3 bar[2]; // location=5, location_frac=2
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*
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* main()
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* {
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* ...
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* }
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*
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* Is rewritten to:
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*
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* mat3x2 foo;
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* vec3 bar[2];
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* out vec4 packed4; // location=4, location_frac=0
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* out vec4 packed5; // location=5, location_frac=0
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* out vec4 packed6; // location=6, location_frac=0
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*
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* main()
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* {
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* ...
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* packed4.xy = foo[0];
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* packed4.zw = foo[1];
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* packed5.xy = foo[2];
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* packed5.zw = bar[0].xy;
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* packed6.x = bar[0].z;
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* packed6.yzw = bar[1];
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* }
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*
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* This lowering pass properly handles "double parking" of a varying vector
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* across two varying slots. For example, in the code above, two of the
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* components of bar[0] are stored in packed5, and the remaining component is
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* stored in packed6.
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*
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* Note that in theory, the extra instructions may cause some loss of
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* performance. However, hopefully in most cases the performance loss will
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* either be absorbed by a later optimization pass, or it will be offset by
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* memory bandwidth savings (because fewer varyings are used).
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*
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* This lowering pass also packs flat floats, ints, and uints together, by
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* using ivec4 as the base type of flat "varyings", and using appropriate
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* casts to convert floats and uints into ints.
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*
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* This lowering pass also handles varyings whose type is a struct or an array
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* of struct. Structs are packed in order and with no gaps, so there may be a
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* performance penalty due to structure elements being double-parked.
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*
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* Lowering of geometry shader inputs is slightly more complex, since geometry
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* inputs are always arrays, so we need to lower arrays to arrays. For
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* example, the following input:
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*
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* in struct Foo {
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* float f;
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* vec3 v;
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* vec2 a[2];
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* } arr[3]; // location=4, location_frac=0
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*
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* Would get lowered like this if it occurred in a fragment shader:
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*
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* struct Foo {
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* float f;
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* vec3 v;
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* vec2 a[2];
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* } arr[3];
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* in vec4 packed4; // location=4, location_frac=0
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* in vec4 packed5; // location=5, location_frac=0
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* in vec4 packed6; // location=6, location_frac=0
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* in vec4 packed7; // location=7, location_frac=0
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* in vec4 packed8; // location=8, location_frac=0
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* in vec4 packed9; // location=9, location_frac=0
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*
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* main()
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* {
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* arr[0].f = packed4.x;
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* arr[0].v = packed4.yzw;
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* arr[0].a[0] = packed5.xy;
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* arr[0].a[1] = packed5.zw;
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* arr[1].f = packed6.x;
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* arr[1].v = packed6.yzw;
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* arr[1].a[0] = packed7.xy;
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* arr[1].a[1] = packed7.zw;
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* arr[2].f = packed8.x;
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* arr[2].v = packed8.yzw;
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* arr[2].a[0] = packed9.xy;
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* arr[2].a[1] = packed9.zw;
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* ...
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* }
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*
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* But it would get lowered like this if it occurred in a geometry shader:
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*
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* struct Foo {
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* float f;
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* vec3 v;
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* vec2 a[2];
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* } arr[3];
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* in vec4 packed4[3]; // location=4, location_frac=0
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* in vec4 packed5[3]; // location=5, location_frac=0
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*
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* main()
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* {
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* arr[0].f = packed4[0].x;
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* arr[0].v = packed4[0].yzw;
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* arr[0].a[0] = packed5[0].xy;
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* arr[0].a[1] = packed5[0].zw;
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* arr[1].f = packed4[1].x;
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* arr[1].v = packed4[1].yzw;
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* arr[1].a[0] = packed5[1].xy;
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* arr[1].a[1] = packed5[1].zw;
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* arr[2].f = packed4[2].x;
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* arr[2].v = packed4[2].yzw;
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* arr[2].a[0] = packed5[2].xy;
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* arr[2].a[1] = packed5[2].zw;
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* ...
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* }
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*/
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#include "glsl_symbol_table.h"
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#include "ir.h"
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#include "ir_optimization.h"
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namespace {
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/**
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* Visitor that performs varying packing. For each varying declared in the
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* shader, this visitor determines whether it needs to be packed. If so, it
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* demotes it to an ordinary global, creates new packed varyings, and
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* generates assignments to convert between the original varying and the
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* packed varying.
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*/
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class lower_packed_varyings_visitor
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{
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public:
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lower_packed_varyings_visitor(void *mem_ctx, unsigned locations_used,
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ir_variable_mode mode,
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unsigned gs_input_vertices,
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exec_list *out_instructions);
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void run(exec_list *instructions);
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private:
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ir_assignment *bitwise_assign_pack(ir_rvalue *lhs, ir_rvalue *rhs);
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ir_assignment *bitwise_assign_unpack(ir_rvalue *lhs, ir_rvalue *rhs);
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unsigned lower_rvalue(ir_rvalue *rvalue, unsigned fine_location,
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ir_variable *unpacked_var, const char *name,
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bool gs_input_toplevel, unsigned vertex_index);
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unsigned lower_arraylike(ir_rvalue *rvalue, unsigned array_size,
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unsigned fine_location,
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ir_variable *unpacked_var, const char *name,
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bool gs_input_toplevel, unsigned vertex_index);
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ir_dereference *get_packed_varying_deref(unsigned location,
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ir_variable *unpacked_var,
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const char *name,
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unsigned vertex_index);
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bool needs_lowering(ir_variable *var);
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/**
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* Memory context used to allocate new instructions for the shader.
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*/
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void * const mem_ctx;
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/**
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* Number of generic varying slots which are used by this shader. This is
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* used to allocate temporary intermediate data structures. If any varying
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* used by this shader has a location greater than or equal to
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* VARYING_SLOT_VAR0 + locations_used, an assertion will fire.
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*/
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const unsigned locations_used;
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/**
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* Array of pointers to the packed varyings that have been created for each
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* generic varying slot. NULL entries in this array indicate varying slots
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* for which a packed varying has not been created yet.
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*/
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ir_variable **packed_varyings;
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/**
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* Type of varying which is being lowered in this pass (either
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* ir_var_shader_in or ir_var_shader_out).
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*/
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const ir_variable_mode mode;
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/**
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* If we are currently lowering geometry shader inputs, the number of input
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* vertices the geometry shader accepts. Otherwise zero.
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*/
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const unsigned gs_input_vertices;
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/**
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* Exec list into which the visitor should insert the packing instructions.
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* Caller provides this list; it should insert the instructions into the
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* appropriate place in the shader once the visitor has finished running.
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*/
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exec_list *out_instructions;
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};
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} /* anonymous namespace */
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lower_packed_varyings_visitor::lower_packed_varyings_visitor(
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void *mem_ctx, unsigned locations_used, ir_variable_mode mode,
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unsigned gs_input_vertices, exec_list *out_instructions)
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: mem_ctx(mem_ctx),
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locations_used(locations_used),
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packed_varyings((ir_variable **)
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rzalloc_array_size(mem_ctx, sizeof(*packed_varyings),
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locations_used)),
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mode(mode),
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gs_input_vertices(gs_input_vertices),
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out_instructions(out_instructions)
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{
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}
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void
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lower_packed_varyings_visitor::run(exec_list *instructions)
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{
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foreach_in_list(ir_instruction, node, instructions) {
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ir_variable *var = node->as_variable();
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if (var == NULL)
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continue;
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if (var->data.mode != this->mode ||
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var->data.location < VARYING_SLOT_VAR0 ||
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!this->needs_lowering(var))
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continue;
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/* This lowering pass is only capable of packing floats and ints
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* together when their interpolation mode is "flat". Therefore, to be
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* safe, caller should ensure that integral varyings always use flat
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* interpolation, even when this is not required by GLSL.
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*/
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assert(var->data.interpolation == INTERP_QUALIFIER_FLAT ||
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!var->type->contains_integer());
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/* Change the old varying into an ordinary global. */
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assert(var->data.mode != ir_var_temporary);
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var->data.mode = ir_var_auto;
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/* Create a reference to the old varying. */
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ir_dereference_variable *deref
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= new(this->mem_ctx) ir_dereference_variable(var);
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/* Recursively pack or unpack it. */
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this->lower_rvalue(deref, var->data.location * 4 + var->data.location_frac, var,
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var->name, this->gs_input_vertices != 0, 0);
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}
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}
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/**
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* Make an ir_assignment from \c rhs to \c lhs, performing appropriate
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* bitcasts if necessary to match up types.
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*
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* This function is called when packing varyings.
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*/
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ir_assignment *
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lower_packed_varyings_visitor::bitwise_assign_pack(ir_rvalue *lhs,
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ir_rvalue *rhs)
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{
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if (lhs->type->base_type != rhs->type->base_type) {
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/* Since we only mix types in flat varyings, and we always store flat
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* varyings as type ivec4, we need only produce conversions from (uint
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* or float) to int.
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*/
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assert(lhs->type->base_type == GLSL_TYPE_INT);
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switch (rhs->type->base_type) {
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case GLSL_TYPE_UINT:
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rhs = new(this->mem_ctx)
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ir_expression(ir_unop_u2i, lhs->type, rhs);
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break;
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case GLSL_TYPE_FLOAT:
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rhs = new(this->mem_ctx)
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ir_expression(ir_unop_bitcast_f2i, lhs->type, rhs);
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break;
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default:
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assert(!"Unexpected type conversion while lowering varyings");
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break;
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}
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}
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return new(this->mem_ctx) ir_assignment(lhs, rhs);
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}
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/**
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* Make an ir_assignment from \c rhs to \c lhs, performing appropriate
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* bitcasts if necessary to match up types.
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*
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* This function is called when unpacking varyings.
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*/
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ir_assignment *
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lower_packed_varyings_visitor::bitwise_assign_unpack(ir_rvalue *lhs,
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ir_rvalue *rhs)
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{
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if (lhs->type->base_type != rhs->type->base_type) {
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/* Since we only mix types in flat varyings, and we always store flat
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* varyings as type ivec4, we need only produce conversions from int to
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* (uint or float).
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*/
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assert(rhs->type->base_type == GLSL_TYPE_INT);
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switch (lhs->type->base_type) {
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case GLSL_TYPE_UINT:
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rhs = new(this->mem_ctx)
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ir_expression(ir_unop_i2u, lhs->type, rhs);
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break;
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case GLSL_TYPE_FLOAT:
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rhs = new(this->mem_ctx)
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ir_expression(ir_unop_bitcast_i2f, lhs->type, rhs);
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break;
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default:
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assert(!"Unexpected type conversion while lowering varyings");
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break;
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}
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}
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return new(this->mem_ctx) ir_assignment(lhs, rhs);
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}
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/**
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* Recursively pack or unpack the given varying (or portion of a varying) by
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* traversing all of its constituent vectors.
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*
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* \param fine_location is the location where the first constituent vector
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* should be packed--the word "fine" indicates that this location is expressed
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* in multiples of a float, rather than multiples of a vec4 as is used
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* elsewhere in Mesa.
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*
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* \param gs_input_toplevel should be set to true if we are lowering geometry
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* shader inputs, and we are currently lowering the whole input variable
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* (i.e. we are lowering the array whose index selects the vertex).
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*
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* \param vertex_index: if we are lowering geometry shader inputs, and the
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* level of the array that we are currently lowering is *not* the top level,
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* then this indicates which vertex we are currently lowering. Otherwise it
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* is ignored.
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*
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* \return the location where the next constituent vector (after this one)
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* should be packed.
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*/
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unsigned
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lower_packed_varyings_visitor::lower_rvalue(ir_rvalue *rvalue,
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unsigned fine_location,
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ir_variable *unpacked_var,
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const char *name,
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bool gs_input_toplevel,
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unsigned vertex_index)
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{
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/* When gs_input_toplevel is set, we should be looking at a geometry shader
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* input array.
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*/
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assert(!gs_input_toplevel || rvalue->type->is_array());
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if (rvalue->type->is_record()) {
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for (unsigned i = 0; i < rvalue->type->length; i++) {
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if (i != 0)
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rvalue = rvalue->clone(this->mem_ctx, NULL);
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const char *field_name = rvalue->type->fields.structure[i].name;
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ir_dereference_record *dereference_record = new(this->mem_ctx)
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ir_dereference_record(rvalue, field_name);
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char *deref_name
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= ralloc_asprintf(this->mem_ctx, "%s.%s", name, field_name);
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fine_location = this->lower_rvalue(dereference_record, fine_location,
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unpacked_var, deref_name, false,
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vertex_index);
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}
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return fine_location;
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} else if (rvalue->type->is_array()) {
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/* Arrays are packed/unpacked by considering each array element in
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* sequence.
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*/
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return this->lower_arraylike(rvalue, rvalue->type->array_size(),
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fine_location, unpacked_var, name,
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gs_input_toplevel, vertex_index);
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} else if (rvalue->type->is_matrix()) {
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/* Matrices are packed/unpacked by considering each column vector in
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* sequence.
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*/
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return this->lower_arraylike(rvalue, rvalue->type->matrix_columns,
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fine_location, unpacked_var, name,
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false, vertex_index);
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} else if (rvalue->type->vector_elements + fine_location % 4 > 4) {
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/* This vector is going to be "double parked" across two varying slots,
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* so handle it as two separate assignments.
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*/
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unsigned left_components = 4 - fine_location % 4;
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unsigned right_components
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= rvalue->type->vector_elements - left_components;
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unsigned left_swizzle_values[4] = { 0, 0, 0, 0 };
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unsigned right_swizzle_values[4] = { 0, 0, 0, 0 };
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char left_swizzle_name[4] = { 0, 0, 0, 0 };
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char right_swizzle_name[4] = { 0, 0, 0, 0 };
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for (unsigned i = 0; i < left_components; i++) {
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left_swizzle_values[i] = i;
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left_swizzle_name[i] = "xyzw"[i];
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}
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for (unsigned i = 0; i < right_components; i++) {
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right_swizzle_values[i] = i + left_components;
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right_swizzle_name[i] = "xyzw"[i + left_components];
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}
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ir_swizzle *left_swizzle = new(this->mem_ctx)
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ir_swizzle(rvalue, left_swizzle_values, left_components);
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ir_swizzle *right_swizzle = new(this->mem_ctx)
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ir_swizzle(rvalue->clone(this->mem_ctx, NULL), right_swizzle_values,
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right_components);
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char *left_name
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= ralloc_asprintf(this->mem_ctx, "%s.%s", name, left_swizzle_name);
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char *right_name
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= ralloc_asprintf(this->mem_ctx, "%s.%s", name, right_swizzle_name);
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fine_location = this->lower_rvalue(left_swizzle, fine_location,
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unpacked_var, left_name, false,
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vertex_index);
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return this->lower_rvalue(right_swizzle, fine_location, unpacked_var,
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right_name, false, vertex_index);
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} else {
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/* No special handling is necessary; pack the rvalue into the
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* varying.
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*/
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unsigned swizzle_values[4] = { 0, 0, 0, 0 };
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unsigned components = rvalue->type->vector_elements;
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unsigned location = fine_location / 4;
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unsigned location_frac = fine_location % 4;
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for (unsigned i = 0; i < components; ++i)
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swizzle_values[i] = i + location_frac;
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ir_dereference *packed_deref =
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this->get_packed_varying_deref(location, unpacked_var, name,
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vertex_index);
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ir_swizzle *swizzle = new(this->mem_ctx)
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ir_swizzle(packed_deref, swizzle_values, components);
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if (this->mode == ir_var_shader_out) {
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ir_assignment *assignment
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= this->bitwise_assign_pack(swizzle, rvalue);
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this->out_instructions->push_tail(assignment);
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} else {
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ir_assignment *assignment
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= this->bitwise_assign_unpack(rvalue, swizzle);
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this->out_instructions->push_tail(assignment);
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}
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return fine_location + components;
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}
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|
}
|
|
|
|
/**
|
|
* Recursively pack or unpack a varying for which we need to iterate over its
|
|
* constituent elements, accessing each one using an ir_dereference_array.
|
|
* This takes care of both arrays and matrices, since ir_dereference_array
|
|
* treats a matrix like an array of its column vectors.
|
|
*
|
|
* \param gs_input_toplevel should be set to true if we are lowering geometry
|
|
* shader inputs, and we are currently lowering the whole input variable
|
|
* (i.e. we are lowering the array whose index selects the vertex).
|
|
*
|
|
* \param vertex_index: if we are lowering geometry shader inputs, and the
|
|
* level of the array that we are currently lowering is *not* the top level,
|
|
* then this indicates which vertex we are currently lowering. Otherwise it
|
|
* is ignored.
|
|
*/
|
|
unsigned
|
|
lower_packed_varyings_visitor::lower_arraylike(ir_rvalue *rvalue,
|
|
unsigned array_size,
|
|
unsigned fine_location,
|
|
ir_variable *unpacked_var,
|
|
const char *name,
|
|
bool gs_input_toplevel,
|
|
unsigned vertex_index)
|
|
{
|
|
for (unsigned i = 0; i < array_size; i++) {
|
|
if (i != 0)
|
|
rvalue = rvalue->clone(this->mem_ctx, NULL);
|
|
ir_constant *constant = new(this->mem_ctx) ir_constant(i);
|
|
ir_dereference_array *dereference_array = new(this->mem_ctx)
|
|
ir_dereference_array(rvalue, constant);
|
|
if (gs_input_toplevel) {
|
|
/* Geometry shader inputs are a special case. Instead of storing
|
|
* each element of the array at a different location, all elements
|
|
* are at the same location, but with a different vertex index.
|
|
*/
|
|
(void) this->lower_rvalue(dereference_array, fine_location,
|
|
unpacked_var, name, false, i);
|
|
} else {
|
|
char *subscripted_name
|
|
= ralloc_asprintf(this->mem_ctx, "%s[%d]", name, i);
|
|
fine_location =
|
|
this->lower_rvalue(dereference_array, fine_location,
|
|
unpacked_var, subscripted_name,
|
|
false, vertex_index);
|
|
}
|
|
}
|
|
return fine_location;
|
|
}
|
|
|
|
/**
|
|
* Retrieve the packed varying corresponding to the given varying location.
|
|
* If no packed varying has been created for the given varying location yet,
|
|
* create it and add it to the shader before returning it.
|
|
*
|
|
* The newly created varying inherits its interpolation parameters from \c
|
|
* unpacked_var. Its base type is ivec4 if we are lowering a flat varying,
|
|
* vec4 otherwise.
|
|
*
|
|
* \param vertex_index: if we are lowering geometry shader inputs, then this
|
|
* indicates which vertex we are currently lowering. Otherwise it is ignored.
|
|
*/
|
|
ir_dereference *
|
|
lower_packed_varyings_visitor::get_packed_varying_deref(
|
|
unsigned location, ir_variable *unpacked_var, const char *name,
|
|
unsigned vertex_index)
|
|
{
|
|
unsigned slot = location - VARYING_SLOT_VAR0;
|
|
assert(slot < locations_used);
|
|
if (this->packed_varyings[slot] == NULL) {
|
|
char *packed_name = ralloc_asprintf(this->mem_ctx, "packed:%s", name);
|
|
const glsl_type *packed_type;
|
|
if (unpacked_var->data.interpolation == INTERP_QUALIFIER_FLAT)
|
|
packed_type = glsl_type::ivec4_type;
|
|
else
|
|
packed_type = glsl_type::vec4_type;
|
|
if (this->gs_input_vertices != 0) {
|
|
packed_type =
|
|
glsl_type::get_array_instance(packed_type,
|
|
this->gs_input_vertices);
|
|
}
|
|
ir_variable *packed_var = new(this->mem_ctx)
|
|
ir_variable(packed_type, packed_name, this->mode);
|
|
if (this->gs_input_vertices != 0) {
|
|
/* Prevent update_array_sizes() from messing with the size of the
|
|
* array.
|
|
*/
|
|
packed_var->data.max_array_access = this->gs_input_vertices - 1;
|
|
}
|
|
packed_var->data.centroid = unpacked_var->data.centroid;
|
|
packed_var->data.sample = unpacked_var->data.sample;
|
|
packed_var->data.interpolation = unpacked_var->data.interpolation;
|
|
packed_var->data.location = location;
|
|
unpacked_var->insert_before(packed_var);
|
|
this->packed_varyings[slot] = packed_var;
|
|
} else {
|
|
/* For geometry shader inputs, only update the packed variable name the
|
|
* first time we visit each component.
|
|
*/
|
|
if (this->gs_input_vertices == 0 || vertex_index == 0) {
|
|
ralloc_asprintf_append((char **) &this->packed_varyings[slot]->name,
|
|
",%s", name);
|
|
}
|
|
}
|
|
|
|
ir_dereference *deref = new(this->mem_ctx)
|
|
ir_dereference_variable(this->packed_varyings[slot]);
|
|
if (this->gs_input_vertices != 0) {
|
|
/* When lowering GS inputs, the packed variable is an array, so we need
|
|
* to dereference it using vertex_index.
|
|
*/
|
|
ir_constant *constant = new(this->mem_ctx) ir_constant(vertex_index);
|
|
deref = new(this->mem_ctx) ir_dereference_array(deref, constant);
|
|
}
|
|
return deref;
|
|
}
|
|
|
|
bool
|
|
lower_packed_varyings_visitor::needs_lowering(ir_variable *var)
|
|
{
|
|
/* Things composed of vec4's and varyings with explicitly assigned
|
|
* locations don't need lowering. Everything else does.
|
|
*/
|
|
if (var->data.explicit_location)
|
|
return false;
|
|
|
|
const glsl_type *type = var->type;
|
|
if (this->gs_input_vertices != 0) {
|
|
assert(type->is_array());
|
|
type = type->element_type();
|
|
}
|
|
if (type->is_array())
|
|
type = type->fields.array;
|
|
if (type->vector_elements == 4)
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
|
|
/**
|
|
* Visitor that splices varying packing code before every use of EmitVertex()
|
|
* in a geometry shader.
|
|
*/
|
|
class lower_packed_varyings_gs_splicer : public ir_hierarchical_visitor
|
|
{
|
|
public:
|
|
explicit lower_packed_varyings_gs_splicer(void *mem_ctx,
|
|
const exec_list *instructions);
|
|
|
|
virtual ir_visitor_status visit_leave(ir_emit_vertex *ev);
|
|
|
|
private:
|
|
/**
|
|
* Memory context used to allocate new instructions for the shader.
|
|
*/
|
|
void * const mem_ctx;
|
|
|
|
/**
|
|
* Instructions that should be spliced into place before each EmitVertex()
|
|
* call.
|
|
*/
|
|
const exec_list *instructions;
|
|
};
|
|
|
|
|
|
lower_packed_varyings_gs_splicer::lower_packed_varyings_gs_splicer(
|
|
void *mem_ctx, const exec_list *instructions)
|
|
: mem_ctx(mem_ctx), instructions(instructions)
|
|
{
|
|
}
|
|
|
|
|
|
ir_visitor_status
|
|
lower_packed_varyings_gs_splicer::visit_leave(ir_emit_vertex *ev)
|
|
{
|
|
foreach_in_list(ir_instruction, ir, this->instructions) {
|
|
ev->insert_before(ir->clone(this->mem_ctx, NULL));
|
|
}
|
|
return visit_continue;
|
|
}
|
|
|
|
|
|
void
|
|
lower_packed_varyings(void *mem_ctx, unsigned locations_used,
|
|
ir_variable_mode mode, unsigned gs_input_vertices,
|
|
gl_shader *shader)
|
|
{
|
|
exec_list *instructions = shader->ir;
|
|
ir_function *main_func = shader->symbols->get_function("main");
|
|
exec_list void_parameters;
|
|
ir_function_signature *main_func_sig
|
|
= main_func->matching_signature(NULL, &void_parameters, false);
|
|
exec_list new_instructions;
|
|
lower_packed_varyings_visitor visitor(mem_ctx, locations_used, mode,
|
|
gs_input_vertices, &new_instructions);
|
|
visitor.run(instructions);
|
|
if (mode == ir_var_shader_out) {
|
|
if (shader->Stage == MESA_SHADER_GEOMETRY) {
|
|
/* For geometry shaders, outputs need to be lowered before each call
|
|
* to EmitVertex()
|
|
*/
|
|
lower_packed_varyings_gs_splicer splicer(mem_ctx, &new_instructions);
|
|
splicer.run(instructions);
|
|
} else {
|
|
/* For other shader types, outputs need to be lowered at the end of
|
|
* main()
|
|
*/
|
|
main_func_sig->body.append_list(&new_instructions);
|
|
}
|
|
} else {
|
|
/* Shader inputs need to be lowered at the beginning of main() */
|
|
main_func_sig->body.head->insert_before(&new_instructions);
|
|
}
|
|
}
|