SPIRV-Cross/spirv_msl.cpp

4595 строки
140 KiB
C++

/*
* Copyright 2016-2018 The Brenwill Workshop Ltd.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "spirv_msl.hpp"
#include "GLSL.std.450.h"
#include <algorithm>
#include <assert.h>
#include <numeric>
using namespace spv;
using namespace spirv_cross;
using namespace std;
static const uint32_t k_unknown_location = ~0u;
static const uint32_t k_unknown_component = ~0u;
CompilerMSL::CompilerMSL(vector<uint32_t> spirv_, vector<MSLVertexAttr> *p_vtx_attrs,
vector<MSLResourceBinding> *p_res_bindings)
: CompilerGLSL(move(spirv_))
{
if (p_vtx_attrs)
for (auto &va : *p_vtx_attrs)
vtx_attrs_by_location[va.location] = &va;
if (p_res_bindings)
for (auto &rb : *p_res_bindings)
resource_bindings.push_back(&rb);
}
CompilerMSL::CompilerMSL(const uint32_t *ir, size_t word_count, MSLVertexAttr *p_vtx_attrs, size_t vtx_attrs_count,
MSLResourceBinding *p_res_bindings, size_t res_bindings_count)
: CompilerGLSL(ir, word_count)
{
if (p_vtx_attrs)
for (size_t i = 0; i < vtx_attrs_count; i++)
vtx_attrs_by_location[p_vtx_attrs[i].location] = &p_vtx_attrs[i];
if (p_res_bindings)
for (size_t i = 0; i < res_bindings_count; i++)
resource_bindings.push_back(&p_res_bindings[i]);
}
void CompilerMSL::build_implicit_builtins()
{
if (need_subpass_input)
{
bool has_frag_coord = false;
for (auto &id : ids)
{
if (id.get_type() != TypeVariable)
continue;
auto &var = id.get<SPIRVariable>();
if (var.storage == StorageClassInput && meta[var.self].decoration.builtin &&
meta[var.self].decoration.builtin_type == BuiltInFragCoord)
{
builtin_frag_coord_id = var.self;
has_frag_coord = true;
break;
}
}
if (!has_frag_coord)
{
uint32_t offset = increase_bound_by(3);
uint32_t type_id = offset;
uint32_t type_ptr_id = offset + 1;
uint32_t var_id = offset + 2;
// Create gl_FragCoord.
SPIRType vec4_type;
vec4_type.basetype = SPIRType::Float;
vec4_type.width = 32;
vec4_type.vecsize = 4;
set<SPIRType>(type_id, vec4_type);
SPIRType vec4_type_ptr;
vec4_type_ptr = vec4_type;
vec4_type_ptr.pointer = true;
vec4_type_ptr.parent_type = type_id;
vec4_type_ptr.storage = StorageClassInput;
auto &ptr_type = set<SPIRType>(type_ptr_id, vec4_type_ptr);
ptr_type.self = type_id;
set<SPIRVariable>(var_id, type_ptr_id, StorageClassInput);
set_decoration(var_id, DecorationBuiltIn, BuiltInFragCoord);
builtin_frag_coord_id = var_id;
}
}
}
static string create_sampler_address(const char *prefix, MSLSamplerAddress addr)
{
switch (addr)
{
case MSL_SAMPLER_ADDRESS_CLAMP_TO_EDGE:
return join(prefix, "address::clamp_to_edge");
case MSL_SAMPLER_ADDRESS_CLAMP_TO_ZERO:
return join(prefix, "address::clamp_to_zero");
case MSL_SAMPLER_ADDRESS_CLAMP_TO_BORDER:
return join(prefix, "address::clamp_to_border");
case MSL_SAMPLER_ADDRESS_REPEAT:
return join(prefix, "address::repeat");
case MSL_SAMPLER_ADDRESS_MIRRORED_REPEAT:
return join(prefix, "address::mirrored_repeat");
default:
SPIRV_CROSS_THROW("Invalid sampler addressing mode.");
}
}
void CompilerMSL::emit_entry_point_declarations()
{
// FIXME: Get test coverage here ...
// Emit constexpr samplers here.
for (auto &samp : constexpr_samplers)
{
auto &var = get<SPIRVariable>(samp.first);
auto &type = get<SPIRType>(var.basetype);
if (type.basetype == SPIRType::Sampler)
add_resource_name(samp.first);
vector<string> args;
auto &s = samp.second;
if (s.coord != MSL_SAMPLER_COORD_NORMALIZED)
args.push_back("coord::pixel");
if (s.min_filter == s.mag_filter)
{
if (s.min_filter != MSL_SAMPLER_FILTER_NEAREST)
args.push_back("filter::linear");
}
else
{
if (s.min_filter != MSL_SAMPLER_FILTER_NEAREST)
args.push_back("min_filter::linear");
if (s.mag_filter != MSL_SAMPLER_FILTER_NEAREST)
args.push_back("mag_filter::linear");
}
switch (s.mip_filter)
{
case MSL_SAMPLER_MIP_FILTER_NONE:
// Default
break;
case MSL_SAMPLER_MIP_FILTER_NEAREST:
args.push_back("mip_filter::nearest");
break;
case MSL_SAMPLER_MIP_FILTER_LINEAR:
args.push_back("mip_filter::linear");
break;
default:
SPIRV_CROSS_THROW("Invalid mip filter.");
}
if (s.s_address == s.t_address && s.s_address == s.r_address)
{
if (s.s_address != MSL_SAMPLER_ADDRESS_CLAMP_TO_EDGE)
args.push_back(create_sampler_address("", s.s_address));
}
else
{
if (s.s_address != MSL_SAMPLER_ADDRESS_CLAMP_TO_EDGE)
args.push_back(create_sampler_address("s_", s.s_address));
if (s.t_address != MSL_SAMPLER_ADDRESS_CLAMP_TO_EDGE)
args.push_back(create_sampler_address("t_", s.t_address));
if (s.r_address != MSL_SAMPLER_ADDRESS_CLAMP_TO_EDGE)
args.push_back(create_sampler_address("r_", s.r_address));
}
if (s.compare_enable)
{
switch (s.compare_func)
{
case MSL_SAMPLER_COMPARE_FUNC_ALWAYS:
args.push_back("compare_func::always");
break;
case MSL_SAMPLER_COMPARE_FUNC_NEVER:
args.push_back("compare_func::never");
break;
case MSL_SAMPLER_COMPARE_FUNC_EQUAL:
args.push_back("compare_func::equal");
break;
case MSL_SAMPLER_COMPARE_FUNC_NOT_EQUAL:
args.push_back("compare_func::not_equal");
break;
case MSL_SAMPLER_COMPARE_FUNC_LESS:
args.push_back("compare_func::less");
break;
case MSL_SAMPLER_COMPARE_FUNC_LESS_EQUAL:
args.push_back("compare_func::less_equal");
break;
case MSL_SAMPLER_COMPARE_FUNC_GREATER:
args.push_back("compare_func::greater");
break;
case MSL_SAMPLER_COMPARE_FUNC_GREATER_EQUAL:
args.push_back("compare_func::greater_equal");
break;
default:
SPIRV_CROSS_THROW("Invalid sampler compare function.");
}
}
if (s.s_address == MSL_SAMPLER_ADDRESS_CLAMP_TO_BORDER || s.t_address == MSL_SAMPLER_ADDRESS_CLAMP_TO_BORDER ||
s.r_address == MSL_SAMPLER_ADDRESS_CLAMP_TO_BORDER)
{
switch (s.border_color)
{
case MSL_SAMPLER_BORDER_COLOR_OPAQUE_BLACK:
args.push_back("border_color::opaque_black");
break;
case MSL_SAMPLER_BORDER_COLOR_OPAQUE_WHITE:
args.push_back("border_color::opaque_white");
break;
case MSL_SAMPLER_BORDER_COLOR_TRANSPARENT_BLACK:
args.push_back("border_color::transparent_black");
break;
default:
SPIRV_CROSS_THROW("Invalid sampler border color.");
}
}
if (s.anisotropy_enable)
args.push_back(join("max_anisotropy(", s.max_anisotropy, ")"));
if (s.lod_clamp_enable)
{
args.push_back(
join("lod_clamp(", convert_to_string(s.lod_clamp_min), ", ", convert_to_string(s.lod_clamp_max), ")"));
}
statement("constexpr sampler ",
type.basetype == SPIRType::SampledImage ? to_sampler_expression(samp.first) : to_name(samp.first),
"(", merge(args), ");");
}
}
string CompilerMSL::compile()
{
// Force a classic "C" locale, reverts when function returns
ClassicLocale classic_locale;
// Do not deal with GLES-isms like precision, older extensions and such.
options.vulkan_semantics = true;
options.es = false;
options.version = 450;
backend.float_literal_suffix = false;
backend.half_literal_suffix = "h";
backend.uint32_t_literal_suffix = true;
backend.basic_int_type = "int";
backend.basic_uint_type = "uint";
backend.discard_literal = "discard_fragment()";
backend.swizzle_is_function = false;
backend.shared_is_implied = false;
backend.use_initializer_list = true;
backend.use_typed_initializer_list = true;
backend.native_row_major_matrix = false;
backend.flexible_member_array_supported = false;
backend.can_declare_arrays_inline = false;
backend.can_return_array = false;
backend.boolean_mix_support = false;
backend.allow_truncated_access_chain = true;
is_rasterization_disabled = msl_options.disable_rasterization;
replace_illegal_names();
struct_member_padding.clear();
build_function_control_flow_graphs_and_analyze();
update_active_builtins();
analyze_image_and_sampler_usage();
build_implicit_builtins();
fixup_image_load_store_access();
set_enabled_interface_variables(get_active_interface_variables());
// Preprocess OpCodes to extract the need to output additional header content
preprocess_op_codes();
// Create structs to hold input, output and uniform variables.
// Do output first to ensure out. is declared at top of entry function.
qual_pos_var_name = "";
stage_out_var_id = add_interface_block(StorageClassOutput);
stage_in_var_id = add_interface_block(StorageClassInput);
stage_uniforms_var_id = add_interface_block(StorageClassUniformConstant);
// Metal vertex functions that define no output must disable rasterization and return void.
if (!stage_out_var_id)
is_rasterization_disabled = true;
// Convert the use of global variables to recursively-passed function parameters
localize_global_variables();
extract_global_variables_from_functions();
// Mark any non-stage-in structs to be tightly packed.
mark_packable_structs();
// Metal does not allow dynamic array lengths.
// Resolve any specialization constants that are used for array lengths.
if (msl_options.resolve_specialized_array_lengths)
resolve_specialized_array_lengths();
uint32_t pass_count = 0;
do
{
if (pass_count >= 3)
SPIRV_CROSS_THROW("Over 3 compilation loops detected. Must be a bug!");
reset();
next_metal_resource_index = MSLResourceBinding(); // Start bindings at zero
// Move constructor for this type is broken on GCC 4.9 ...
buffer = unique_ptr<ostringstream>(new ostringstream());
emit_header();
emit_specialization_constants();
emit_resources();
emit_custom_functions();
emit_function(get<SPIRFunction>(entry_point), Bitset());
pass_count++;
} while (force_recompile);
return buffer->str();
}
string CompilerMSL::compile(vector<MSLVertexAttr> *p_vtx_attrs, vector<MSLResourceBinding> *p_res_bindings)
{
if (p_vtx_attrs)
{
vtx_attrs_by_location.clear();
for (auto &va : *p_vtx_attrs)
vtx_attrs_by_location[va.location] = &va;
}
if (p_res_bindings)
{
resource_bindings.clear();
for (auto &rb : *p_res_bindings)
resource_bindings.push_back(&rb);
}
return compile();
}
string CompilerMSL::compile(MSLConfiguration &msl_cfg, vector<MSLVertexAttr> *p_vtx_attrs,
vector<MSLResourceBinding> *p_res_bindings)
{
msl_options = msl_cfg;
return compile(p_vtx_attrs, p_res_bindings);
}
// Register the need to output any custom functions.
void CompilerMSL::preprocess_op_codes()
{
OpCodePreprocessor preproc(*this);
traverse_all_reachable_opcodes(get<SPIRFunction>(entry_point), preproc);
if (preproc.suppress_missing_prototypes)
add_pragma_line("#pragma clang diagnostic ignored \"-Wmissing-prototypes\"");
if (preproc.uses_atomics)
{
add_header_line("#include <metal_atomic>");
add_pragma_line("#pragma clang diagnostic ignored \"-Wunused-variable\"");
}
// Metal vertex functions that write to resources must disable rasterization and return void.
if (preproc.uses_resource_write)
is_rasterization_disabled = true;
}
// Move the Private and Workgroup global variables to the entry function.
// Non-constant variables cannot have global scope in Metal.
void CompilerMSL::localize_global_variables()
{
auto &entry_func = get<SPIRFunction>(entry_point);
auto iter = global_variables.begin();
while (iter != global_variables.end())
{
uint32_t v_id = *iter;
auto &var = get<SPIRVariable>(v_id);
if (var.storage == StorageClassPrivate || var.storage == StorageClassWorkgroup)
{
entry_func.add_local_variable(v_id);
iter = global_variables.erase(iter);
}
else
iter++;
}
}
// Metal does not allow dynamic array lengths.
// Turn off specialization of any constants that are used for array lengths.
void CompilerMSL::resolve_specialized_array_lengths()
{
for (auto &id : ids)
{
if (id.get_type() == TypeConstant)
{
auto &c = id.get<SPIRConstant>();
if (c.is_used_as_array_length)
c.specialization = false;
}
}
}
// For any global variable accessed directly by a function,
// extract that variable and add it as an argument to that function.
void CompilerMSL::extract_global_variables_from_functions()
{
// Uniforms
unordered_set<uint32_t> global_var_ids;
for (auto &id : ids)
{
if (id.get_type() == TypeVariable)
{
auto &var = id.get<SPIRVariable>();
if (var.storage == StorageClassInput || var.storage == StorageClassOutput ||
var.storage == StorageClassUniform || var.storage == StorageClassUniformConstant ||
var.storage == StorageClassPushConstant || var.storage == StorageClassStorageBuffer)
{
global_var_ids.insert(var.self);
}
}
}
// Local vars that are declared in the main function and accessed directly by a function
auto &entry_func = get<SPIRFunction>(entry_point);
for (auto &var : entry_func.local_variables)
if (get<SPIRVariable>(var).storage != StorageClassFunction)
global_var_ids.insert(var);
std::set<uint32_t> added_arg_ids;
unordered_set<uint32_t> processed_func_ids;
extract_global_variables_from_function(entry_point, added_arg_ids, global_var_ids, processed_func_ids);
}
// MSL does not support the use of global variables for shader input content.
// For any global variable accessed directly by the specified function, extract that variable,
// add it as an argument to that function, and the arg to the added_arg_ids collection.
void CompilerMSL::extract_global_variables_from_function(uint32_t func_id, std::set<uint32_t> &added_arg_ids,
unordered_set<uint32_t> &global_var_ids,
unordered_set<uint32_t> &processed_func_ids)
{
// Avoid processing a function more than once
if (processed_func_ids.find(func_id) != processed_func_ids.end())
{
// Return function global variables
added_arg_ids = function_global_vars[func_id];
return;
}
processed_func_ids.insert(func_id);
auto &func = get<SPIRFunction>(func_id);
// Recursively establish global args added to functions on which we depend.
for (auto block : func.blocks)
{
auto &b = get<SPIRBlock>(block);
for (auto &i : b.ops)
{
auto ops = stream(i);
auto op = static_cast<Op>(i.op);
switch (op)
{
case OpLoad:
case OpInBoundsAccessChain:
case OpAccessChain:
{
uint32_t base_id = ops[2];
if (global_var_ids.find(base_id) != global_var_ids.end())
added_arg_ids.insert(base_id);
auto &type = get<SPIRType>(ops[0]);
if (type.basetype == SPIRType::Image && type.image.dim == DimSubpassData)
{
// Implicitly reads gl_FragCoord.
assert(builtin_frag_coord_id != 0);
added_arg_ids.insert(builtin_frag_coord_id);
}
break;
}
case OpFunctionCall:
{
// First see if any of the function call args are globals
for (uint32_t arg_idx = 3; arg_idx < i.length; arg_idx++)
{
uint32_t arg_id = ops[arg_idx];
if (global_var_ids.find(arg_id) != global_var_ids.end())
added_arg_ids.insert(arg_id);
}
// Then recurse into the function itself to extract globals used internally in the function
uint32_t inner_func_id = ops[2];
std::set<uint32_t> inner_func_args;
extract_global_variables_from_function(inner_func_id, inner_func_args, global_var_ids,
processed_func_ids);
added_arg_ids.insert(inner_func_args.begin(), inner_func_args.end());
break;
}
case OpStore:
{
uint32_t base_id = ops[0];
if (global_var_ids.find(base_id) != global_var_ids.end())
added_arg_ids.insert(base_id);
break;
}
default:
break;
}
// TODO: Add all other operations which can affect memory.
// We should consider a more unified system here to reduce boiler-plate.
// This kind of analysis is done in several places ...
}
}
function_global_vars[func_id] = added_arg_ids;
// Add the global variables as arguments to the function
if (func_id != entry_point)
{
for (uint32_t arg_id : added_arg_ids)
{
auto &var = get<SPIRVariable>(arg_id);
uint32_t type_id = var.basetype;
auto *p_type = &get<SPIRType>(type_id);
if (is_builtin_variable(var) && p_type->basetype == SPIRType::Struct)
{
// Get the non-pointer type
type_id = get_non_pointer_type_id(type_id);
p_type = &get<SPIRType>(type_id);
uint32_t mbr_idx = 0;
for (auto &mbr_type_id : p_type->member_types)
{
BuiltIn builtin;
bool is_builtin = is_member_builtin(*p_type, mbr_idx, &builtin);
if (is_builtin && has_active_builtin(builtin, var.storage))
{
// Add a arg variable with the same type and decorations as the member
uint32_t next_ids = increase_bound_by(2);
uint32_t ptr_type_id = next_ids + 0;
uint32_t var_id = next_ids + 1;
// Make sure we have an actual pointer type,
// so that we will get the appropriate address space when declaring these builtins.
auto &ptr = set<SPIRType>(ptr_type_id, get<SPIRType>(mbr_type_id));
ptr.self = mbr_type_id;
ptr.storage = var.storage;
ptr.pointer = true;
func.add_parameter(mbr_type_id, var_id, true);
set<SPIRVariable>(var_id, ptr_type_id, StorageClassFunction);
meta[var_id].decoration = meta[type_id].members[mbr_idx];
}
mbr_idx++;
}
}
else
{
uint32_t next_id = increase_bound_by(1);
func.add_parameter(type_id, next_id, true);
set<SPIRVariable>(next_id, type_id, StorageClassFunction, 0, arg_id);
// Ensure the existing variable has a valid name and the new variable has all the same meta info
set_name(arg_id, ensure_valid_name(to_name(arg_id), "v"));
meta[next_id] = meta[arg_id];
}
}
}
}
// For all variables that are some form of non-input-output interface block, mark that all the structs
// that are recursively contained within the type referenced by that variable should be packed tightly.
void CompilerMSL::mark_packable_structs()
{
for (auto &id : ids)
{
if (id.get_type() == TypeVariable)
{
auto &var = id.get<SPIRVariable>();
if (var.storage != StorageClassFunction && !is_hidden_variable(var))
{
auto &type = get<SPIRType>(var.basetype);
if (type.pointer &&
(type.storage == StorageClassUniform || type.storage == StorageClassUniformConstant ||
type.storage == StorageClassPushConstant || type.storage == StorageClassStorageBuffer) &&
(has_decoration(type.self, DecorationBlock) || has_decoration(type.self, DecorationBufferBlock)))
mark_as_packable(type);
}
}
}
}
// If the specified type is a struct, it and any nested structs
// are marked as packable with the DecorationCPacked decoration,
void CompilerMSL::mark_as_packable(SPIRType &type)
{
// If this is not the base type (eg. it's a pointer or array), tunnel down
if (type.parent_type)
{
mark_as_packable(get<SPIRType>(type.parent_type));
return;
}
if (type.basetype == SPIRType::Struct)
{
set_decoration(type.self, DecorationCPacked);
// Recurse
size_t mbr_cnt = type.member_types.size();
for (uint32_t mbr_idx = 0; mbr_idx < mbr_cnt; mbr_idx++)
{
uint32_t mbr_type_id = type.member_types[mbr_idx];
auto &mbr_type = get<SPIRType>(mbr_type_id);
mark_as_packable(mbr_type);
if (mbr_type.type_alias)
{
auto &mbr_type_alias = get<SPIRType>(mbr_type.type_alias);
mark_as_packable(mbr_type_alias);
}
}
}
}
// If a vertex attribute exists at the location, it is marked as being used by this shader
void CompilerMSL::mark_location_as_used_by_shader(uint32_t location, StorageClass storage)
{
MSLVertexAttr *p_va;
if ((get_entry_point().model == ExecutionModelVertex) && (storage == StorageClassInput) &&
(p_va = vtx_attrs_by_location[location]))
p_va->used_by_shader = true;
}
// Add an interface structure for the type of storage, which is either StorageClassInput or StorageClassOutput.
// Returns the ID of the newly added variable, or zero if no variable was added.
uint32_t CompilerMSL::add_interface_block(StorageClass storage)
{
// Accumulate the variables that should appear in the interface struct
vector<SPIRVariable *> vars;
bool incl_builtins = (storage == StorageClassOutput);
for (auto &id : ids)
{
if (id.get_type() == TypeVariable)
{
auto &var = id.get<SPIRVariable>();
auto &type = get<SPIRType>(var.basetype);
if (var.storage == storage && interface_variable_exists_in_entry_point(var.self) &&
!is_hidden_variable(var, incl_builtins) && type.pointer)
{
vars.push_back(&var);
}
}
}
// If no variables qualify, leave
if (vars.empty())
return 0;
// Add a new typed variable for this interface structure.
// The initializer expression is allocated here, but populated when the function
// declaraion is emitted, because it is cleared after each compilation pass.
uint32_t next_id = increase_bound_by(3);
uint32_t ib_type_id = next_id++;
auto &ib_type = set<SPIRType>(ib_type_id);
ib_type.basetype = SPIRType::Struct;
ib_type.storage = storage;
set_decoration(ib_type_id, DecorationBlock);
uint32_t ib_var_id = next_id++;
auto &var = set<SPIRVariable>(ib_var_id, ib_type_id, storage, 0);
var.initializer = next_id++;
string ib_var_ref;
switch (storage)
{
case StorageClassInput:
ib_var_ref = stage_in_var_name;
break;
case StorageClassOutput:
{
ib_var_ref = stage_out_var_name;
// Add the output interface struct as a local variable to the entry function.
// If the entry point should return the output struct, set the entry function
// to return the output interface struct, otherwise to return nothing.
// Indicate the output var requires early initialization.
bool ep_should_return_output = !get_is_rasterization_disabled();
uint32_t rtn_id = ep_should_return_output ? ib_var_id : 0;
auto &entry_func = get<SPIRFunction>(entry_point);
entry_func.add_local_variable(ib_var_id);
for (auto &blk_id : entry_func.blocks)
{
auto &blk = get<SPIRBlock>(blk_id);
if (blk.terminator == SPIRBlock::Return)
blk.return_value = rtn_id;
}
vars_needing_early_declaration.push_back(ib_var_id);
break;
}
case StorageClassUniformConstant:
{
ib_var_ref = stage_uniform_var_name;
active_interface_variables.insert(ib_var_id); // Ensure will be emitted
break;
}
default:
break;
}
set_name(ib_type_id, to_name(entry_point) + "_" + ib_var_ref);
set_name(ib_var_id, ib_var_ref);
for (auto p_var : vars)
{
uint32_t type_id = p_var->basetype;
auto &type = get<SPIRType>(type_id);
if (type.basetype == SPIRType::Struct)
{
// Flatten the struct members into the interface struct
uint32_t mbr_idx = 0;
for (auto &mbr_type_id : type.member_types)
{
BuiltIn builtin;
bool is_builtin = is_member_builtin(type, mbr_idx, &builtin);
bool is_flat = has_member_decoration(type.self, mbr_idx, DecorationFlat) ||
has_decoration(p_var->self, DecorationFlat);
bool is_noperspective = has_member_decoration(type.self, mbr_idx, DecorationNoPerspective) ||
has_decoration(p_var->self, DecorationNoPerspective);
bool is_centroid = has_member_decoration(type.self, mbr_idx, DecorationCentroid) ||
has_decoration(p_var->self, DecorationCentroid);
bool is_sample = has_member_decoration(type.self, mbr_idx, DecorationSample) ||
has_decoration(p_var->self, DecorationSample);
if (!is_builtin || has_active_builtin(builtin, storage))
{
// Add a reference to the member to the interface struct.
uint32_t ib_mbr_idx = uint32_t(ib_type.member_types.size());
mbr_type_id = ensure_correct_builtin_type(mbr_type_id, builtin);
type.member_types[mbr_idx] = mbr_type_id;
ib_type.member_types.push_back(mbr_type_id);
// Give the member a name
string mbr_name = ensure_valid_name(to_qualified_member_name(type, mbr_idx), "m");
set_member_name(ib_type_id, ib_mbr_idx, mbr_name);
// Update the original variable reference to include the structure reference
string qual_var_name = ib_var_ref + "." + mbr_name;
set_member_qualified_name(type_id, mbr_idx, qual_var_name);
// Copy the variable location from the original variable to the member
if (has_member_decoration(type_id, mbr_idx, DecorationLocation))
{
uint32_t locn = get_member_decoration(type_id, mbr_idx, DecorationLocation);
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationLocation, locn);
mark_location_as_used_by_shader(locn, storage);
}
else if (has_decoration(p_var->self, DecorationLocation))
{
// The block itself might have a location and in this case, all members of the block
// receive incrementing locations.
uint32_t locn = get_decoration(p_var->self, DecorationLocation) + mbr_idx;
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationLocation, locn);
mark_location_as_used_by_shader(locn, storage);
}
// Copy the component location, if present.
if (has_member_decoration(type_id, mbr_idx, DecorationComponent))
{
uint32_t comp = get_member_decoration(type_id, mbr_idx, DecorationComponent);
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationComponent, comp);
}
// Mark the member as builtin if needed
if (is_builtin)
{
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationBuiltIn, builtin);
if (builtin == BuiltInPosition)
qual_pos_var_name = qual_var_name;
}
// Copy interpolation decorations if needed
if (is_flat)
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationFlat);
if (is_noperspective)
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationNoPerspective);
if (is_centroid)
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationCentroid);
if (is_sample)
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationSample);
}
mbr_idx++;
}
}
else if (type.basetype == SPIRType::Boolean || type.basetype == SPIRType::Char ||
type.basetype == SPIRType::Int || type.basetype == SPIRType::UInt ||
type.basetype == SPIRType::Int64 || type.basetype == SPIRType::UInt64 ||
type_is_floating_point(type) || type.basetype == SPIRType::Boolean)
{
bool is_builtin = is_builtin_variable(*p_var);
BuiltIn builtin = BuiltIn(get_decoration(p_var->self, DecorationBuiltIn));
bool is_flat = has_decoration(p_var->self, DecorationFlat);
bool is_noperspective = has_decoration(p_var->self, DecorationNoPerspective);
bool is_centroid = has_decoration(p_var->self, DecorationCentroid);
bool is_sample = has_decoration(p_var->self, DecorationSample);
if (!is_builtin || has_active_builtin(builtin, storage))
{
// MSL does not allow matrices or arrays in input or output variables, so need to handle it specially.
if (!is_builtin && (storage == StorageClassInput || storage == StorageClassOutput) &&
(is_matrix(type) || is_array(type)))
{
uint32_t elem_cnt = 0;
if (is_matrix(type))
{
if (is_array(type))
SPIRV_CROSS_THROW("MSL cannot emit arrays-of-matrices in input and output variables.");
elem_cnt = type.columns;
}
else if (is_array(type))
{
if (type.array.size() != 1)
SPIRV_CROSS_THROW("MSL cannot emit arrays-of-arrays in input and output variables.");
elem_cnt = type.array_size_literal.back() ? type.array.back() :
get<SPIRConstant>(type.array.back()).scalar();
}
auto *usable_type = &type;
while (is_array(*usable_type) || is_matrix(*usable_type))
usable_type = &get<SPIRType>(usable_type->parent_type);
auto &entry_func = get<SPIRFunction>(entry_point);
entry_func.add_local_variable(p_var->self);
// We need to declare the variable early and at entry-point scope.
vars_needing_early_declaration.push_back(p_var->self);
for (uint32_t i = 0; i < elem_cnt; i++)
{
// Add a reference to the variable type to the interface struct.
uint32_t ib_mbr_idx = uint32_t(ib_type.member_types.size());
ib_type.member_types.push_back(usable_type->self);
// Give the member a name
string mbr_name = ensure_valid_name(join(to_expression(p_var->self), "_", i), "m");
set_member_name(ib_type_id, ib_mbr_idx, mbr_name);
// There is no qualified alias since we need to flatten the internal array on return.
if (get_decoration_bitset(p_var->self).get(DecorationLocation))
{
uint32_t locn = get_decoration(p_var->self, DecorationLocation) + i;
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationLocation, locn);
mark_location_as_used_by_shader(locn, storage);
}
if (get_decoration_bitset(p_var->self).get(DecorationIndex))
{
uint32_t index = get_decoration(p_var->self, DecorationIndex);
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationIndex, index);
}
// Copy interpolation decorations if needed
if (is_flat)
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationFlat);
if (is_noperspective)
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationNoPerspective);
if (is_centroid)
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationCentroid);
if (is_sample)
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationSample);
switch (storage)
{
case StorageClassInput:
entry_func.fixup_statements_in.push_back(
join(to_name(p_var->self), "[", i, "] = ", ib_var_ref, ".", mbr_name, ";"));
break;
case StorageClassOutput:
entry_func.fixup_statements_out.push_back(
join(ib_var_ref, ".", mbr_name, " = ", to_name(p_var->self), "[", i, "];"));
break;
default:
break;
}
}
}
else
{
// Add a reference to the variable type to the interface struct.
uint32_t ib_mbr_idx = uint32_t(ib_type.member_types.size());
type_id = ensure_correct_builtin_type(type_id, builtin);
p_var->basetype = type_id;
ib_type.member_types.push_back(type_id);
// Give the member a name
string mbr_name = ensure_valid_name(to_expression(p_var->self), "m");
set_member_name(ib_type_id, ib_mbr_idx, mbr_name);
// Update the original variable reference to include the structure reference
string qual_var_name = ib_var_ref + "." + mbr_name;
meta[p_var->self].decoration.qualified_alias = qual_var_name;
// Copy the variable location from the original variable to the member
if (get_decoration_bitset(p_var->self).get(DecorationLocation))
{
uint32_t locn = get_decoration(p_var->self, DecorationLocation);
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationLocation, locn);
mark_location_as_used_by_shader(locn, storage);
}
if (get_decoration_bitset(p_var->self).get(DecorationComponent))
{
uint32_t comp = get_decoration(p_var->self, DecorationComponent);
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationComponent, comp);
}
if (get_decoration_bitset(p_var->self).get(DecorationIndex))
{
uint32_t index = get_decoration(p_var->self, DecorationIndex);
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationIndex, index);
}
// Mark the member as builtin if needed
if (is_builtin)
{
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationBuiltIn, builtin);
if (builtin == BuiltInPosition)
qual_pos_var_name = qual_var_name;
}
// Copy interpolation decorations if needed
if (is_flat)
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationFlat);
if (is_noperspective)
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationNoPerspective);
if (is_centroid)
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationCentroid);
if (is_sample)
set_member_decoration(ib_type_id, ib_mbr_idx, DecorationSample);
}
}
}
}
// Sort the members of the structure by their locations.
MemberSorter member_sorter(ib_type, meta[ib_type_id], MemberSorter::Location);
member_sorter.sort();
return ib_var_id;
}
// Ensure that the type is compatible with the builtin.
// If it is, simply return the given type ID.
// Otherwise, create a new type, and return it's ID.
uint32_t CompilerMSL::ensure_correct_builtin_type(uint32_t type_id, BuiltIn builtin)
{
auto &type = get<SPIRType>(type_id);
if (builtin == BuiltInSampleMask && is_array(type))
{
uint32_t next_id = increase_bound_by(type.pointer ? 2 : 1);
uint32_t base_type_id = next_id++;
auto &base_type = set<SPIRType>(base_type_id);
base_type.basetype = SPIRType::UInt;
base_type.width = 32;
if (!type.pointer)
return base_type_id;
uint32_t ptr_type_id = next_id++;
auto &ptr_type = set<SPIRType>(ptr_type_id);
ptr_type = base_type;
ptr_type.pointer = true;
ptr_type.storage = type.storage;
ptr_type.parent_type = base_type_id;
return ptr_type_id;
}
return type_id;
}
// Sort the members of the struct type by offset, and pack and then pad members where needed
// to align MSL members with SPIR-V offsets. The struct members are iterated twice. Packing
// occurs first, followed by padding, because packing a member reduces both its size and its
// natural alignment, possibly requiring a padding member to be added ahead of it.
void CompilerMSL::align_struct(SPIRType &ib_type)
{
uint32_t &ib_type_id = ib_type.self;
// Sort the members of the interface structure by their offset.
// They should already be sorted per SPIR-V spec anyway.
MemberSorter member_sorter(ib_type, meta[ib_type_id], MemberSorter::Offset);
member_sorter.sort();
uint32_t curr_offset;
uint32_t mbr_cnt = uint32_t(ib_type.member_types.size());
// Test the alignment of each member, and if a member should be closer to the previous
// member than the default spacing expects, it is likely that the previous member is in
// a packed format. If so, and the previous member is packable, pack it.
// For example...this applies to any 3-element vector that is followed by a scalar.
curr_offset = 0;
for (uint32_t mbr_idx = 0; mbr_idx < mbr_cnt; mbr_idx++)
{
if (is_member_packable(ib_type, mbr_idx))
set_member_decoration(ib_type_id, mbr_idx, DecorationCPacked);
// Align current offset to the current member's default alignment.
size_t align_mask = get_declared_struct_member_alignment(ib_type, mbr_idx) - 1;
curr_offset = uint32_t((curr_offset + align_mask) & ~align_mask);
// Fetch the member offset as declared in the SPIRV.
uint32_t mbr_offset = get_member_decoration(ib_type_id, mbr_idx, DecorationOffset);
if (mbr_offset > curr_offset)
{
// Since MSL and SPIR-V have slightly different struct member alignment and
// size rules, we'll pad to standard C-packing rules. If the member is farther
// away than C-packing, expects, add an inert padding member before the the member.
MSLStructMemberKey key = get_struct_member_key(ib_type_id, mbr_idx);
struct_member_padding[key] = mbr_offset - curr_offset;
}
// Increment the current offset to be positioned immediately after the current member.
curr_offset = mbr_offset + uint32_t(get_declared_struct_member_size(ib_type, mbr_idx));
}
}
// Returns whether the specified struct member supports a packable type
// variation that is smaller than the unpacked variation of that type.
bool CompilerMSL::is_member_packable(SPIRType &ib_type, uint32_t index)
{
// We've already marked it as packable
if (has_member_decoration(ib_type.self, index, DecorationCPacked))
return true;
auto &mbr_type = get<SPIRType>(ib_type.member_types[index]);
// Only 3-element vectors or 3-row matrices need to be packed.
if (mbr_type.vecsize != 3)
return false;
// Only row-major matrices need to be packed.
if (is_matrix(mbr_type) && !has_member_decoration(ib_type.self, index, DecorationRowMajor))
return false;
uint32_t component_size = mbr_type.width / 8;
uint32_t unpacked_mbr_size = component_size * (mbr_type.vecsize + 1) * mbr_type.columns;
if (is_array(mbr_type))
{
// If member is an array, and the array stride is larger than the type needs, don't pack it.
// Take into consideration multi-dimentional arrays.
uint32_t md_elem_cnt = 1;
size_t last_elem_idx = mbr_type.array.size() - 1;
for (uint32_t i = 0; i < last_elem_idx; i++)
md_elem_cnt *= max(to_array_size_literal(mbr_type, i), 1U);
uint32_t unpacked_array_stride = unpacked_mbr_size * md_elem_cnt;
uint32_t array_stride = type_struct_member_array_stride(ib_type, index);
return unpacked_array_stride > array_stride;
}
else
{
// Pack if there is not enough space between this member and next.
// If last member, only pack if it's a row-major matrix.
if (index < ib_type.member_types.size() - 1)
{
uint32_t mbr_offset_curr = get_member_decoration(ib_type.self, index, DecorationOffset);
uint32_t mbr_offset_next = get_member_decoration(ib_type.self, index + 1, DecorationOffset);
return unpacked_mbr_size > mbr_offset_next - mbr_offset_curr;
}
else
return is_matrix(mbr_type);
}
}
// Returns a combination of type ID and member index for use as hash key
MSLStructMemberKey CompilerMSL::get_struct_member_key(uint32_t type_id, uint32_t index)
{
MSLStructMemberKey k = type_id;
k <<= 32;
k += index;
return k;
}
// Converts the format of the current expression from packed to unpacked,
// by wrapping the expression in a constructor of the appropriate type.
string CompilerMSL::unpack_expression_type(string expr_str, const SPIRType &type)
{
return join(type_to_glsl(type), "(", expr_str, ")");
}
// Emits the file header info
void CompilerMSL::emit_header()
{
for (auto &pragma : pragma_lines)
statement(pragma);
if (!pragma_lines.empty())
statement("");
statement("#include <metal_stdlib>");
statement("#include <simd/simd.h>");
for (auto &header : header_lines)
statement(header);
statement("");
statement("using namespace metal;");
statement("");
for (auto &td : typedef_lines)
statement(td);
if (!typedef_lines.empty())
statement("");
}
void CompilerMSL::add_pragma_line(const string &line)
{
auto rslt = pragma_lines.insert(line);
if (rslt.second)
force_recompile = true;
}
void CompilerMSL::add_typedef_line(const string &line)
{
auto rslt = typedef_lines.insert(line);
if (rslt.second)
force_recompile = true;
}
// Emits any needed custom function bodies.
void CompilerMSL::emit_custom_functions()
{
for (auto &spv_func : spv_function_implementations)
{
switch (spv_func)
{
case SPVFuncImplMod:
statement("// Implementation of the GLSL mod() function, which is slightly different than Metal fmod()");
statement("template<typename Tx, typename Ty>");
statement("Tx mod(Tx x, Ty y)");
begin_scope();
statement("return x - y * floor(x / y);");
end_scope();
statement("");
break;
case SPVFuncImplRadians:
statement("// Implementation of the GLSL radians() function");
statement("template<typename T>");
statement("T radians(T d)");
begin_scope();
statement("return d * T(0.01745329251);");
end_scope();
statement("");
break;
case SPVFuncImplDegrees:
statement("// Implementation of the GLSL degrees() function");
statement("template<typename T>");
statement("T degrees(T r)");
begin_scope();
statement("return r * T(57.2957795131);");
end_scope();
statement("");
break;
case SPVFuncImplFindILsb:
statement("// Implementation of the GLSL findLSB() function");
statement("template<typename T>");
statement("T findLSB(T x)");
begin_scope();
statement("return select(ctz(x), T(-1), x == T(0));");
end_scope();
statement("");
break;
case SPVFuncImplFindUMsb:
statement("// Implementation of the unsigned GLSL findMSB() function");
statement("template<typename T>");
statement("T findUMSB(T x)");
begin_scope();
statement("return select(clz(T(0)) - (clz(x) + T(1)), T(-1), x == T(0));");
end_scope();
statement("");
break;
case SPVFuncImplFindSMsb:
statement("// Implementation of the signed GLSL findMSB() function");
statement("template<typename T>");
statement("T findSMSB(T x)");
begin_scope();
statement("T v = select(x, T(-1) - x, x < T(0));");
statement("return select(clz(T(0)) - (clz(v) + T(1)), T(-1), v == T(0));");
end_scope();
statement("");
break;
case SPVFuncImplArrayCopy:
statement("// Implementation of an array copy function to cover GLSL's ability to copy an array via "
"assignment.");
statement("template<typename T, uint N>");
statement("void spvArrayCopy(thread T (&dst)[N], thread const T (&src)[N])");
begin_scope();
statement("for (uint i = 0; i < N; dst[i] = src[i], i++);");
end_scope();
statement("");
statement("// An overload for constant arrays.");
statement("template<typename T, uint N>");
statement("void spvArrayCopyConstant(thread T (&dst)[N], constant T (&src)[N])");
begin_scope();
statement("for (uint i = 0; i < N; dst[i] = src[i], i++);");
end_scope();
statement("");
break;
case SPVFuncImplTexelBufferCoords:
{
string tex_width_str = convert_to_string(msl_options.texel_buffer_texture_width);
statement("// Returns 2D texture coords corresponding to 1D texel buffer coords");
statement("uint2 spvTexelBufferCoord(uint tc)");
begin_scope();
statement(join("return uint2(tc % ", tex_width_str, ", tc / ", tex_width_str, ");"));
end_scope();
statement("");
break;
}
case SPVFuncImplInverse4x4:
statement("// Returns the determinant of a 2x2 matrix.");
statement("inline float spvDet2x2(float a1, float a2, float b1, float b2)");
begin_scope();
statement("return a1 * b2 - b1 * a2;");
end_scope();
statement("");
statement("// Returns the determinant of a 3x3 matrix.");
statement("inline float spvDet3x3(float a1, float a2, float a3, float b1, float b2, float b3, float c1, "
"float c2, float c3)");
begin_scope();
statement("return a1 * spvDet2x2(b2, b3, c2, c3) - b1 * spvDet2x2(a2, a3, c2, c3) + c1 * spvDet2x2(a2, a3, "
"b2, b3);");
end_scope();
statement("");
statement("// Returns the inverse of a matrix, by using the algorithm of calculating the classical");
statement("// adjoint and dividing by the determinant. The contents of the matrix are changed.");
statement("float4x4 spvInverse4x4(float4x4 m)");
begin_scope();
statement("float4x4 adj; // The adjoint matrix (inverse after dividing by determinant)");
statement_no_indent("");
statement("// Create the transpose of the cofactors, as the classical adjoint of the matrix.");
statement("adj[0][0] = spvDet3x3(m[1][1], m[1][2], m[1][3], m[2][1], m[2][2], m[2][3], m[3][1], m[3][2], "
"m[3][3]);");
statement("adj[0][1] = -spvDet3x3(m[0][1], m[0][2], m[0][3], m[2][1], m[2][2], m[2][3], m[3][1], m[3][2], "
"m[3][3]);");
statement("adj[0][2] = spvDet3x3(m[0][1], m[0][2], m[0][3], m[1][1], m[1][2], m[1][3], m[3][1], m[3][2], "
"m[3][3]);");
statement("adj[0][3] = -spvDet3x3(m[0][1], m[0][2], m[0][3], m[1][1], m[1][2], m[1][3], m[2][1], m[2][2], "
"m[2][3]);");
statement_no_indent("");
statement("adj[1][0] = -spvDet3x3(m[1][0], m[1][2], m[1][3], m[2][0], m[2][2], m[2][3], m[3][0], m[3][2], "
"m[3][3]);");
statement("adj[1][1] = spvDet3x3(m[0][0], m[0][2], m[0][3], m[2][0], m[2][2], m[2][3], m[3][0], m[3][2], "
"m[3][3]);");
statement("adj[1][2] = -spvDet3x3(m[0][0], m[0][2], m[0][3], m[1][0], m[1][2], m[1][3], m[3][0], m[3][2], "
"m[3][3]);");
statement("adj[1][3] = spvDet3x3(m[0][0], m[0][2], m[0][3], m[1][0], m[1][2], m[1][3], m[2][0], m[2][2], "
"m[2][3]);");
statement_no_indent("");
statement("adj[2][0] = spvDet3x3(m[1][0], m[1][1], m[1][3], m[2][0], m[2][1], m[2][3], m[3][0], m[3][1], "
"m[3][3]);");
statement("adj[2][1] = -spvDet3x3(m[0][0], m[0][1], m[0][3], m[2][0], m[2][1], m[2][3], m[3][0], m[3][1], "
"m[3][3]);");
statement("adj[2][2] = spvDet3x3(m[0][0], m[0][1], m[0][3], m[1][0], m[1][1], m[1][3], m[3][0], m[3][1], "
"m[3][3]);");
statement("adj[2][3] = -spvDet3x3(m[0][0], m[0][1], m[0][3], m[1][0], m[1][1], m[1][3], m[2][0], m[2][1], "
"m[2][3]);");
statement_no_indent("");
statement("adj[3][0] = -spvDet3x3(m[1][0], m[1][1], m[1][2], m[2][0], m[2][1], m[2][2], m[3][0], m[3][1], "
"m[3][2]);");
statement("adj[3][1] = spvDet3x3(m[0][0], m[0][1], m[0][2], m[2][0], m[2][1], m[2][2], m[3][0], m[3][1], "
"m[3][2]);");
statement("adj[3][2] = -spvDet3x3(m[0][0], m[0][1], m[0][2], m[1][0], m[1][1], m[1][2], m[3][0], m[3][1], "
"m[3][2]);");
statement("adj[3][3] = spvDet3x3(m[0][0], m[0][1], m[0][2], m[1][0], m[1][1], m[1][2], m[2][0], m[2][1], "
"m[2][2]);");
statement_no_indent("");
statement("// Calculate the determinant as a combination of the cofactors of the first row.");
statement("float det = (adj[0][0] * m[0][0]) + (adj[0][1] * m[1][0]) + (adj[0][2] * m[2][0]) + (adj[0][3] "
"* m[3][0]);");
statement_no_indent("");
statement("// Divide the classical adjoint matrix by the determinant.");
statement("// If determinant is zero, matrix is not invertable, so leave it unchanged.");
statement("return (det != 0.0f) ? (adj * (1.0f / det)) : m;");
end_scope();
statement("");
break;
case SPVFuncImplInverse3x3:
if (spv_function_implementations.count(SPVFuncImplInverse4x4) == 0)
{
statement("// Returns the determinant of a 2x2 matrix.");
statement("inline float spvDet2x2(float a1, float a2, float b1, float b2)");
begin_scope();
statement("return a1 * b2 - b1 * a2;");
end_scope();
statement("");
}
statement("// Returns the inverse of a matrix, by using the algorithm of calculating the classical");
statement("// adjoint and dividing by the determinant. The contents of the matrix are changed.");
statement("float3x3 spvInverse3x3(float3x3 m)");
begin_scope();
statement("float3x3 adj; // The adjoint matrix (inverse after dividing by determinant)");
statement_no_indent("");
statement("// Create the transpose of the cofactors, as the classical adjoint of the matrix.");
statement("adj[0][0] = spvDet2x2(m[1][1], m[1][2], m[2][1], m[2][2]);");
statement("adj[0][1] = -spvDet2x2(m[0][1], m[0][2], m[2][1], m[2][2]);");
statement("adj[0][2] = spvDet2x2(m[0][1], m[0][2], m[1][1], m[1][2]);");
statement_no_indent("");
statement("adj[1][0] = -spvDet2x2(m[1][0], m[1][2], m[2][0], m[2][2]);");
statement("adj[1][1] = spvDet2x2(m[0][0], m[0][2], m[2][0], m[2][2]);");
statement("adj[1][2] = -spvDet2x2(m[0][0], m[0][2], m[1][0], m[1][2]);");
statement_no_indent("");
statement("adj[2][0] = spvDet2x2(m[1][0], m[1][1], m[2][0], m[2][1]);");
statement("adj[2][1] = -spvDet2x2(m[0][0], m[0][1], m[2][0], m[2][1]);");
statement("adj[2][2] = spvDet2x2(m[0][0], m[0][1], m[1][0], m[1][1]);");
statement_no_indent("");
statement("// Calculate the determinant as a combination of the cofactors of the first row.");
statement("float det = (adj[0][0] * m[0][0]) + (adj[0][1] * m[1][0]) + (adj[0][2] * m[2][0]);");
statement_no_indent("");
statement("// Divide the classical adjoint matrix by the determinant.");
statement("// If determinant is zero, matrix is not invertable, so leave it unchanged.");
statement("return (det != 0.0f) ? (adj * (1.0f / det)) : m;");
end_scope();
statement("");
break;
case SPVFuncImplInverse2x2:
statement("// Returns the inverse of a matrix, by using the algorithm of calculating the classical");
statement("// adjoint and dividing by the determinant. The contents of the matrix are changed.");
statement("float2x2 spvInverse2x2(float2x2 m)");
begin_scope();
statement("float2x2 adj; // The adjoint matrix (inverse after dividing by determinant)");
statement_no_indent("");
statement("// Create the transpose of the cofactors, as the classical adjoint of the matrix.");
statement("adj[0][0] = m[1][1];");
statement("adj[0][1] = -m[0][1];");
statement_no_indent("");
statement("adj[1][0] = -m[1][0];");
statement("adj[1][1] = m[0][0];");
statement_no_indent("");
statement("// Calculate the determinant as a combination of the cofactors of the first row.");
statement("float det = (adj[0][0] * m[0][0]) + (adj[0][1] * m[1][0]);");
statement_no_indent("");
statement("// Divide the classical adjoint matrix by the determinant.");
statement("// If determinant is zero, matrix is not invertable, so leave it unchanged.");
statement("return (det != 0.0f) ? (adj * (1.0f / det)) : m;");
end_scope();
statement("");
break;
case SPVFuncImplRowMajor2x3:
statement("// Implementation of a conversion of matrix content from RowMajor to ColumnMajor organization.");
statement("float2x3 spvConvertFromRowMajor2x3(float2x3 m)");
begin_scope();
statement("return float2x3(float3(m[0][0], m[0][2], m[1][1]), float3(m[0][1], m[1][0], m[1][2]));");
end_scope();
statement("");
break;
case SPVFuncImplRowMajor2x4:
statement("// Implementation of a conversion of matrix content from RowMajor to ColumnMajor organization.");
statement("float2x4 spvConvertFromRowMajor2x4(float2x4 m)");
begin_scope();
statement("return float2x4(float4(m[0][0], m[0][2], m[1][0], m[1][2]), float4(m[0][1], m[0][3], m[1][1], "
"m[1][3]));");
end_scope();
statement("");
break;
case SPVFuncImplRowMajor3x2:
statement("// Implementation of a conversion of matrix content from RowMajor to ColumnMajor organization.");
statement("float3x2 spvConvertFromRowMajor3x2(float3x2 m)");
begin_scope();
statement("return float3x2(float2(m[0][0], m[1][1]), float2(m[0][1], m[2][0]), float2(m[1][0], m[2][1]));");
end_scope();
statement("");
break;
case SPVFuncImplRowMajor3x4:
statement("// Implementation of a conversion of matrix content from RowMajor to ColumnMajor organization.");
statement("float3x4 spvConvertFromRowMajor3x4(float3x4 m)");
begin_scope();
statement("return float3x4(float4(m[0][0], m[0][3], m[1][2], m[2][1]), float4(m[0][1], m[1][0], m[1][3], "
"m[2][2]), float4(m[0][2], m[1][1], m[2][0], m[2][3]));");
end_scope();
statement("");
break;
case SPVFuncImplRowMajor4x2:
statement("// Implementation of a conversion of matrix content from RowMajor to ColumnMajor organization.");
statement("float4x2 spvConvertFromRowMajor4x2(float4x2 m)");
begin_scope();
statement("return float4x2(float2(m[0][0], m[2][0]), float2(m[0][1], m[2][1]), float2(m[1][0], m[3][0]), "
"float2(m[1][1], m[3][1]));");
end_scope();
statement("");
break;
case SPVFuncImplRowMajor4x3:
statement("// Implementation of a conversion of matrix content from RowMajor to ColumnMajor organization.");
statement("float4x3 spvConvertFromRowMajor4x3(float4x3 m)");
begin_scope();
statement("return float4x3(float3(m[0][0], m[1][1], m[2][2]), float3(m[0][1], m[1][2], m[3][0]), "
"float3(m[0][2], m[2][0], m[3][1]), float3(m[1][0], m[2][1], m[3][2]));");
end_scope();
statement("");
break;
default:
break;
}
}
}
// Undefined global memory is not allowed in MSL.
// Declare constant and init to zeros. Use {}, as global constructors can break Metal.
void CompilerMSL::declare_undefined_values()
{
bool emitted = false;
for (auto &id : ids)
{
if (id.get_type() == TypeUndef)
{
auto &undef = id.get<SPIRUndef>();
auto &type = get<SPIRType>(undef.basetype);
statement("constant ", variable_decl(type, to_name(undef.self), undef.self), " = {};");
emitted = true;
}
}
if (emitted)
statement("");
}
void CompilerMSL::declare_constant_arrays()
{
// MSL cannot declare arrays inline (except when declaring a variable), so we must move them out to
// global constants directly, so we are able to use constants as variable expressions.
bool emitted = false;
for (auto &id : ids)
{
if (id.get_type() == TypeConstant)
{
auto &c = id.get<SPIRConstant>();
if (c.specialization)
continue;
auto &type = get<SPIRType>(c.constant_type);
if (!type.array.empty())
{
auto name = to_name(c.self);
statement("constant ", variable_decl(type, name), " = ", constant_expression(c), ";");
emitted = true;
}
}
}
if (emitted)
statement("");
}
void CompilerMSL::emit_resources()
{
// Output non-interface structs. These include local function structs
// and structs nested within uniform and read-write buffers.
unordered_set<uint32_t> declared_structs;
for (auto &id : ids)
{
if (id.get_type() == TypeType)
{
auto &type = id.get<SPIRType>();
uint32_t type_id = type.self;
bool is_struct = (type.basetype == SPIRType::Struct) && type.array.empty();
bool is_block =
has_decoration(type.self, DecorationBlock) || has_decoration(type.self, DecorationBufferBlock);
bool is_basic_struct = is_struct && !type.pointer && !is_block;
bool is_interface = (type.storage == StorageClassInput || type.storage == StorageClassOutput ||
type.storage == StorageClassUniformConstant);
bool is_non_interface_block = is_struct && type.pointer && is_block && !is_interface;
bool is_declarable_struct = is_basic_struct || is_non_interface_block;
// Align and emit declarable structs...but avoid declaring each more than once.
if (is_declarable_struct && declared_structs.count(type_id) == 0)
{
declared_structs.insert(type_id);
if (has_decoration(type_id, DecorationCPacked))
align_struct(type);
emit_struct(type);
}
}
}
declare_constant_arrays();
declare_undefined_values();
// Output interface structs.
emit_interface_block(stage_out_var_id);
emit_interface_block(stage_in_var_id);
emit_interface_block(stage_uniforms_var_id);
}
// Emit declarations for the specialization Metal function constants
void CompilerMSL::emit_specialization_constants()
{
SpecializationConstant wg_x, wg_y, wg_z;
uint32_t workgroup_size_id = get_work_group_size_specialization_constants(wg_x, wg_y, wg_z);
bool emitted = false;
for (auto &id : ids)
{
if (id.get_type() == TypeConstant)
{
auto &c = id.get<SPIRConstant>();
if (!c.specialization)
continue;
// If WorkGroupSize is a specialization constant, it will be declared explicitly below.
if (c.self == workgroup_size_id)
continue;
auto &type = get<SPIRType>(c.constant_type);
string sc_type_name = type_to_glsl(type);
string sc_name = to_name(c.self);
string sc_tmp_name = sc_name + "_tmp";
// Function constants are only supported in MSL 1.2 and later.
// If we don't support it just declare the "default" directly.
// This "default" value can be overridden to the true specialization constant by the API user.
if (msl_options.supports_msl_version(1, 2) && has_decoration(c.self, DecorationSpecId))
{
uint32_t constant_id = get_decoration(c.self, DecorationSpecId);
// Only scalar, non-composite values can be function constants.
statement("constant ", sc_type_name, " ", sc_tmp_name, " [[function_constant(", constant_id, ")]];");
statement("constant ", sc_type_name, " ", sc_name, " = is_function_constant_defined(", sc_tmp_name,
") ? ", sc_tmp_name, " : ", constant_expression(c), ";");
}
else
{
// Composite specialization constants must be built from other specialization constants.
statement("constant ", sc_type_name, " ", sc_name, " = ", constant_expression(c), ";");
}
emitted = true;
}
else if (id.get_type() == TypeConstantOp)
{
auto &c = id.get<SPIRConstantOp>();
auto &type = get<SPIRType>(c.basetype);
auto name = to_name(c.self);
statement("constant ", variable_decl(type, name), " = ", constant_op_expression(c), ";");
emitted = true;
}
}
// TODO: This can be expressed as a [[threads_per_threadgroup]] input semantic, but we need to know
// the work group size at compile time in SPIR-V, and [[threads_per_threadgroup]] would need to be passed around as a global.
// The work group size may be a specialization constant.
if (workgroup_size_id)
{
statement("constant uint3 ", builtin_to_glsl(BuiltInWorkgroupSize, StorageClassWorkgroup), " = ",
constant_expression(get<SPIRConstant>(workgroup_size_id)), ";");
emitted = true;
}
if (emitted)
statement("");
}
void CompilerMSL::emit_binary_unord_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1,
const char *op)
{
bool forward = should_forward(op0) && should_forward(op1);
emit_op(result_type, result_id,
join("(isunordered(", to_enclosed_unpacked_expression(op0), ", ", to_enclosed_unpacked_expression(op1),
") || ", to_enclosed_unpacked_expression(op0), " ", op, " ", to_enclosed_unpacked_expression(op1),
")"),
forward);
inherit_expression_dependencies(result_id, op0);
inherit_expression_dependencies(result_id, op1);
}
// Override for MSL-specific syntax instructions
void CompilerMSL::emit_instruction(const Instruction &instruction)
{
#define MSL_BOP(op) emit_binary_op(ops[0], ops[1], ops[2], ops[3], #op)
#define MSL_BOP_CAST(op, type) \
emit_binary_op_cast(ops[0], ops[1], ops[2], ops[3], #op, type, opcode_is_sign_invariant(opcode))
#define MSL_UOP(op) emit_unary_op(ops[0], ops[1], ops[2], #op)
#define MSL_QFOP(op) emit_quaternary_func_op(ops[0], ops[1], ops[2], ops[3], ops[4], ops[5], #op)
#define MSL_TFOP(op) emit_trinary_func_op(ops[0], ops[1], ops[2], ops[3], ops[4], #op)
#define MSL_BFOP(op) emit_binary_func_op(ops[0], ops[1], ops[2], ops[3], #op)
#define MSL_BFOP_CAST(op, type) \
emit_binary_func_op_cast(ops[0], ops[1], ops[2], ops[3], #op, type, opcode_is_sign_invariant(opcode))
#define MSL_UFOP(op) emit_unary_func_op(ops[0], ops[1], ops[2], #op)
#define MSL_UNORD_BOP(op) emit_binary_unord_op(ops[0], ops[1], ops[2], ops[3], #op)
auto ops = stream(instruction);
auto opcode = static_cast<Op>(instruction.op);
switch (opcode)
{
// Comparisons
case OpIEqual:
case OpLogicalEqual:
case OpFOrdEqual:
MSL_BOP(==);
break;
case OpINotEqual:
case OpLogicalNotEqual:
case OpFOrdNotEqual:
MSL_BOP(!=);
break;
case OpUGreaterThan:
case OpSGreaterThan:
case OpFOrdGreaterThan:
MSL_BOP(>);
break;
case OpUGreaterThanEqual:
case OpSGreaterThanEqual:
case OpFOrdGreaterThanEqual:
MSL_BOP(>=);
break;
case OpULessThan:
case OpSLessThan:
case OpFOrdLessThan:
MSL_BOP(<);
break;
case OpULessThanEqual:
case OpSLessThanEqual:
case OpFOrdLessThanEqual:
MSL_BOP(<=);
break;
case OpFUnordEqual:
MSL_UNORD_BOP(==);
break;
case OpFUnordNotEqual:
MSL_UNORD_BOP(!=);
break;
case OpFUnordGreaterThan:
MSL_UNORD_BOP(>);
break;
case OpFUnordGreaterThanEqual:
MSL_UNORD_BOP(>=);
break;
case OpFUnordLessThan:
MSL_UNORD_BOP(<);
break;
case OpFUnordLessThanEqual:
MSL_UNORD_BOP(<=);
break;
// Derivatives
case OpDPdx:
case OpDPdxFine:
case OpDPdxCoarse:
MSL_UFOP(dfdx);
register_control_dependent_expression(ops[1]);
break;
case OpDPdy:
case OpDPdyFine:
case OpDPdyCoarse:
MSL_UFOP(dfdy);
register_control_dependent_expression(ops[1]);
break;
case OpFwidth:
case OpFwidthCoarse:
case OpFwidthFine:
MSL_UFOP(fwidth);
register_control_dependent_expression(ops[1]);
break;
// Bitfield
case OpBitFieldInsert:
MSL_QFOP(insert_bits);
break;
case OpBitFieldSExtract:
case OpBitFieldUExtract:
MSL_TFOP(extract_bits);
break;
case OpBitReverse:
MSL_UFOP(reverse_bits);
break;
case OpBitCount:
MSL_UFOP(popcount);
break;
case OpFRem:
MSL_BFOP(fmod);
break;
// Atomics
case OpAtomicExchange:
{
uint32_t result_type = ops[0];
uint32_t id = ops[1];
uint32_t ptr = ops[2];
uint32_t mem_sem = ops[4];
uint32_t val = ops[5];
emit_atomic_func_op(result_type, id, "atomic_exchange_explicit", mem_sem, mem_sem, false, ptr, val);
break;
}
case OpAtomicCompareExchange:
{
uint32_t result_type = ops[0];
uint32_t id = ops[1];
uint32_t ptr = ops[2];
uint32_t mem_sem_pass = ops[4];
uint32_t mem_sem_fail = ops[5];
uint32_t val = ops[6];
uint32_t comp = ops[7];
emit_atomic_func_op(result_type, id, "atomic_compare_exchange_weak_explicit", mem_sem_pass, mem_sem_fail, true,
ptr, comp, true, val);
break;
}
case OpAtomicCompareExchangeWeak:
SPIRV_CROSS_THROW("OpAtomicCompareExchangeWeak is only supported in kernel profile.");
case OpAtomicLoad:
{
uint32_t result_type = ops[0];
uint32_t id = ops[1];
uint32_t ptr = ops[2];
uint32_t mem_sem = ops[4];
emit_atomic_func_op(result_type, id, "atomic_load_explicit", mem_sem, mem_sem, false, ptr, 0);
break;
}
case OpAtomicStore:
{
uint32_t result_type = expression_type(ops[0]).self;
uint32_t id = ops[0];
uint32_t ptr = ops[0];
uint32_t mem_sem = ops[2];
uint32_t val = ops[3];
emit_atomic_func_op(result_type, id, "atomic_store_explicit", mem_sem, mem_sem, false, ptr, val);
break;
}
#define MSL_AFMO_IMPL(op, valsrc) \
do \
{ \
uint32_t result_type = ops[0]; \
uint32_t id = ops[1]; \
uint32_t ptr = ops[2]; \
uint32_t mem_sem = ops[4]; \
uint32_t val = valsrc; \
emit_atomic_func_op(result_type, id, "atomic_fetch_" #op "_explicit", mem_sem, mem_sem, false, ptr, val); \
} while (false)
#define MSL_AFMO(op) MSL_AFMO_IMPL(op, ops[5])
#define MSL_AFMIO(op) MSL_AFMO_IMPL(op, 1)
case OpAtomicIIncrement:
MSL_AFMIO(add);
break;
case OpAtomicIDecrement:
MSL_AFMIO(sub);
break;
case OpAtomicIAdd:
MSL_AFMO(add);
break;
case OpAtomicISub:
MSL_AFMO(sub);
break;
case OpAtomicSMin:
case OpAtomicUMin:
MSL_AFMO(min);
break;
case OpAtomicSMax:
case OpAtomicUMax:
MSL_AFMO(max);
break;
case OpAtomicAnd:
MSL_AFMO(and);
break;
case OpAtomicOr:
MSL_AFMO(or);
break;
case OpAtomicXor:
MSL_AFMO(xor);
break;
// Images
// Reads == Fetches in Metal
case OpImageRead:
{
// Mark that this shader reads from this image
uint32_t img_id = ops[2];
auto &type = expression_type(img_id);
if (type.image.dim != DimSubpassData)
{
auto *p_var = maybe_get_backing_variable(img_id);
if (p_var && has_decoration(p_var->self, DecorationNonReadable))
{
unset_decoration(p_var->self, DecorationNonReadable);
force_recompile = true;
}
}
emit_texture_op(instruction);
break;
}
case OpImageWrite:
{
uint32_t img_id = ops[0];
uint32_t coord_id = ops[1];
uint32_t texel_id = ops[2];
const uint32_t *opt = &ops[3];
uint32_t length = instruction.length - 3;
// Bypass pointers because we need the real image struct
auto &type = expression_type(img_id);
auto &img_type = get<SPIRType>(type.self);
// Ensure this image has been marked as being written to and force a
// recommpile so that the image type output will include write access
auto *p_var = maybe_get_backing_variable(img_id);
if (p_var && has_decoration(p_var->self, DecorationNonWritable))
{
unset_decoration(p_var->self, DecorationNonWritable);
force_recompile = true;
}
bool forward = false;
uint32_t bias = 0;
uint32_t lod = 0;
uint32_t flags = 0;
if (length)
{
flags = *opt++;
length--;
}
auto test = [&](uint32_t &v, uint32_t flag) {
if (length && (flags & flag))
{
v = *opt++;
length--;
}
};
test(bias, ImageOperandsBiasMask);
test(lod, ImageOperandsLodMask);
statement(join(
to_expression(img_id), ".write(", to_expression(texel_id), ", ",
to_function_args(img_id, img_type, true, false, false, coord_id, 0, 0, 0, 0, lod, 0, 0, 0, 0, 0, &forward),
");"));
if (p_var && variable_storage_is_aliased(*p_var))
flush_all_aliased_variables();
break;
}
case OpImageQuerySize:
case OpImageQuerySizeLod:
{
uint32_t rslt_type_id = ops[0];
auto &rslt_type = get<SPIRType>(rslt_type_id);
uint32_t id = ops[1];
uint32_t img_id = ops[2];
string img_exp = to_expression(img_id);
auto &img_type = expression_type(img_id);
Dim img_dim = img_type.image.dim;
bool img_is_array = img_type.image.arrayed;
if (img_type.basetype != SPIRType::Image)
SPIRV_CROSS_THROW("Invalid type for OpImageQuerySize.");
string lod;
if (opcode == OpImageQuerySizeLod)
{
// LOD index defaults to zero, so don't bother outputing level zero index
string decl_lod = to_expression(ops[3]);
if (decl_lod != "0")
lod = decl_lod;
}
string expr = type_to_glsl(rslt_type) + "(";
expr += img_exp + ".get_width(" + lod + ")";
if (img_dim == Dim2D || img_dim == DimCube || img_dim == Dim3D)
expr += ", " + img_exp + ".get_height(" + lod + ")";
if (img_dim == Dim3D)
expr += ", " + img_exp + ".get_depth(" + lod + ")";
if (img_is_array)
expr += ", " + img_exp + ".get_array_size()";
expr += ")";
emit_op(rslt_type_id, id, expr, should_forward(img_id));
break;
}
#define MSL_ImgQry(qrytype) \
do \
{ \
uint32_t rslt_type_id = ops[0]; \
auto &rslt_type = get<SPIRType>(rslt_type_id); \
uint32_t id = ops[1]; \
uint32_t img_id = ops[2]; \
string img_exp = to_expression(img_id); \
string expr = type_to_glsl(rslt_type) + "(" + img_exp + ".get_num_" #qrytype "())"; \
emit_op(rslt_type_id, id, expr, should_forward(img_id)); \
} while (false)
case OpImageQueryLevels:
MSL_ImgQry(mip_levels);
break;
case OpImageQuerySamples:
MSL_ImgQry(samples);
break;
// Casting
case OpQuantizeToF16:
{
uint32_t result_type = ops[0];
uint32_t id = ops[1];
uint32_t arg = ops[2];
string exp;
auto &type = get<SPIRType>(result_type);
switch (type.vecsize)
{
case 1:
exp = join("float(half(", to_expression(arg), "))");
break;
case 2:
exp = join("float2(half2(", to_expression(arg), "))");
break;
case 3:
exp = join("float3(half3(", to_expression(arg), "))");
break;
case 4:
exp = join("float4(half4(", to_expression(arg), "))");
break;
default:
SPIRV_CROSS_THROW("Illegal argument to OpQuantizeToF16.");
}
emit_op(result_type, id, exp, should_forward(arg));
break;
}
case OpStore:
if (maybe_emit_input_struct_assignment(ops[0], ops[1]))
break;
if (maybe_emit_array_assignment(ops[0], ops[1]))
break;
CompilerGLSL::emit_instruction(instruction);
break;
// Compute barriers
case OpMemoryBarrier:
emit_barrier(0, ops[0], ops[1]);
break;
case OpControlBarrier:
// In GLSL a memory barrier is often followed by a control barrier.
// But in MSL, memory barriers are also control barriers, so don't
// emit a simple control barrier if a memory barrier has just been emitted.
if (previous_instruction_opcode != OpMemoryBarrier)
emit_barrier(ops[0], ops[1], ops[2]);
break;
case OpVectorTimesMatrix:
case OpMatrixTimesVector:
{
// If the matrix needs transpose and it is square or packed, just flip the multiply order.
uint32_t mtx_id = ops[opcode == OpMatrixTimesVector ? 2 : 3];
auto *e = maybe_get<SPIRExpression>(mtx_id);
auto &t = expression_type(mtx_id);
bool is_packed = has_decoration(mtx_id, DecorationCPacked);
if (e && e->need_transpose && (t.columns == t.vecsize || is_packed))
{
e->need_transpose = false;
// This is important for matrices. Packed matrices
// are generally transposed, so unpacking using a constructor argument
// will result in an error.
// The simplest solution for now is to just avoid unpacking the matrix in this operation.
unset_decoration(mtx_id, DecorationCPacked);
emit_binary_op(ops[0], ops[1], ops[3], ops[2], "*");
if (is_packed)
set_decoration(mtx_id, DecorationCPacked);
e->need_transpose = true;
}
else
MSL_BOP(*);
break;
}
// OpOuterProduct
default:
CompilerGLSL::emit_instruction(instruction);
break;
}
previous_instruction_opcode = opcode;
}
void CompilerMSL::emit_barrier(uint32_t id_exe_scope, uint32_t id_mem_scope, uint32_t id_mem_sem)
{
if (get_entry_point().model != ExecutionModelGLCompute)
return;
string bar_stmt = "threadgroup_barrier(mem_flags::";
uint32_t mem_sem = id_mem_sem ? get<SPIRConstant>(id_mem_sem).scalar() : uint32_t(MemorySemanticsMaskNone);
if (mem_sem & MemorySemanticsCrossWorkgroupMemoryMask)
bar_stmt += "mem_device";
else if (mem_sem & (MemorySemanticsSubgroupMemoryMask | MemorySemanticsWorkgroupMemoryMask |
MemorySemanticsAtomicCounterMemoryMask))
bar_stmt += "mem_threadgroup";
else if (mem_sem & MemorySemanticsImageMemoryMask)
bar_stmt += "mem_texture";
else
bar_stmt += "mem_none";
if (msl_options.is_ios() && msl_options.supports_msl_version(2))
{
bar_stmt += ", ";
// Use the wider of the two scopes (smaller value)
uint32_t exe_scope = id_exe_scope ? get<SPIRConstant>(id_exe_scope).scalar() : uint32_t(ScopeInvocation);
uint32_t mem_scope = id_mem_scope ? get<SPIRConstant>(id_mem_scope).scalar() : uint32_t(ScopeInvocation);
uint32_t scope = min(exe_scope, mem_scope);
switch (scope)
{
case ScopeCrossDevice:
case ScopeDevice:
bar_stmt += "memory_scope_device";
break;
case ScopeSubgroup:
case ScopeInvocation:
bar_stmt += "memory_scope_simdgroup";
break;
case ScopeWorkgroup:
default:
bar_stmt += "memory_scope_threadgroup";
break;
}
}
bar_stmt += ");";
statement(bar_stmt);
assert(current_emitting_block);
flush_control_dependent_expressions(current_emitting_block->self);
flush_all_active_variables();
}
// Since MSL does not allow structs to be nested within the stage_in struct, the original input
// structs are flattened into a single stage_in struct by add_interface_block. As a result,
// if the LHS and RHS represent an assignment of an entire input struct, we must perform this
// member-by-member, mapping each RHS member to its name in the flattened stage_in struct.
// Returns whether the struct assignment was emitted.
bool CompilerMSL::maybe_emit_input_struct_assignment(uint32_t id_lhs, uint32_t id_rhs)
{
// We only care about assignments of an entire struct
uint32_t type_id = expression_type_id(id_rhs);
auto &type = get<SPIRType>(type_id);
if (type.basetype != SPIRType::Struct)
return false;
// We only care about assignments from Input variables
auto *p_v_rhs = maybe_get_backing_variable(id_rhs);
if (!(p_v_rhs && p_v_rhs->storage == StorageClassInput))
return false;
// Get the ID of the type of the underlying RHS variable.
// This will be an Input OpTypePointer containing the qualified member names.
uint32_t tid_v_rhs = p_v_rhs->basetype;
// Ensure the LHS variable has been declared
auto *p_v_lhs = maybe_get_backing_variable(id_lhs);
if (p_v_lhs)
flush_variable_declaration(p_v_lhs->self);
size_t mbr_cnt = type.member_types.size();
for (uint32_t mbr_idx = 0; mbr_idx < mbr_cnt; mbr_idx++)
{
string expr;
//LHS
expr += to_name(id_lhs);
expr += ".";
expr += to_member_name(type, mbr_idx);
expr += " = ";
//RHS
string qual_mbr_name = get_member_qualified_name(tid_v_rhs, mbr_idx);
if (qual_mbr_name.empty())
{
expr += to_name(id_rhs);
expr += ".";
expr += to_member_name(type, mbr_idx);
}
else
expr += qual_mbr_name;
statement(expr, ";");
}
return true;
}
void CompilerMSL::emit_array_copy(const string &lhs, uint32_t rhs_id)
{
// Assignment from an array initializer is fine.
if (ids[rhs_id].get_type() == TypeConstant)
statement("spvArrayCopyConstant(", lhs, ", ", to_expression(rhs_id), ");");
else
statement("spvArrayCopy(", lhs, ", ", to_expression(rhs_id), ");");
}
// Since MSL does not allow arrays to be copied via simple variable assignment,
// if the LHS and RHS represent an assignment of an entire array, it must be
// implemented by calling an array copy function.
// Returns whether the struct assignment was emitted.
bool CompilerMSL::maybe_emit_array_assignment(uint32_t id_lhs, uint32_t id_rhs)
{
// We only care about assignments of an entire array
auto &type = expression_type(id_rhs);
if (type.array.size() == 0)
return false;
auto *var = maybe_get<SPIRVariable>(id_lhs);
// Is this a remapped, static constant? Don't do anything.
if (var && var->remapped_variable && var->statically_assigned)
return true;
if (ids[id_rhs].get_type() == TypeConstant && var && var->deferred_declaration)
{
// Special case, if we end up declaring a variable when assigning the constant array,
// we can avoid the copy by directly assigning the constant expression.
// This is likely necessary to be able to use a variable as a true look-up table, as it is unlikely
// the compiler will be able to optimize the spvArrayCopy() into a constant LUT.
// After a variable has been declared, we can no longer assign constant arrays in MSL unfortunately.
statement(to_expression(id_lhs), " = ", constant_expression(get<SPIRConstant>(id_rhs)), ";");
return true;
}
// Ensure the LHS variable has been declared
auto *p_v_lhs = maybe_get_backing_variable(id_lhs);
if (p_v_lhs)
flush_variable_declaration(p_v_lhs->self);
emit_array_copy(to_expression(id_lhs), id_rhs);
register_write(id_lhs);
return true;
}
// Emits one of the atomic functions. In MSL, the atomic functions operate on pointers
void CompilerMSL::emit_atomic_func_op(uint32_t result_type, uint32_t result_id, const char *op, uint32_t mem_order_1,
uint32_t mem_order_2, bool has_mem_order_2, uint32_t obj, uint32_t op1,
bool op1_is_pointer, uint32_t op2)
{
forced_temporaries.insert(result_id);
string exp = string(op) + "(";
auto &type = expression_type(obj);
exp += "(volatile ";
auto *var = maybe_get_backing_variable(obj);
if (!var)
SPIRV_CROSS_THROW("No backing variable for atomic operation.");
exp += get_argument_address_space(*var);
exp += " atomic_";
exp += type_to_glsl(type);
exp += "*)";
exp += "&";
exp += to_enclosed_expression(obj);
bool is_atomic_compare_exchange_strong = op1_is_pointer && op1;
if (is_atomic_compare_exchange_strong)
{
assert(strcmp(op, "atomic_compare_exchange_weak_explicit") == 0);
assert(op2);
assert(has_mem_order_2);
exp += ", &";
exp += to_name(result_id);
exp += ", ";
exp += to_expression(op2);
exp += ", ";
exp += get_memory_order(mem_order_1);
exp += ", ";
exp += get_memory_order(mem_order_2);
exp += ")";
// MSL only supports the weak atomic compare exchange,
// so emit a CAS loop here.
statement(variable_decl(type, to_name(result_id)), ";");
statement("do");
begin_scope();
statement(to_name(result_id), " = ", to_expression(op1), ";");
end_scope_decl(join("while (!", exp, ")"));
set<SPIRExpression>(result_id, to_name(result_id), result_type, true);
}
else
{
assert(strcmp(op, "atomic_compare_exchange_weak_explicit") != 0);
if (op1)
exp += ", " + to_expression(op1);
if (op2)
exp += ", " + to_expression(op2);
exp += string(", ") + get_memory_order(mem_order_1);
if (has_mem_order_2)
exp += string(", ") + get_memory_order(mem_order_2);
exp += ")";
emit_op(result_type, result_id, exp, false);
}
flush_all_atomic_capable_variables();
}
// Metal only supports relaxed memory order for now
const char *CompilerMSL::get_memory_order(uint32_t)
{
return "memory_order_relaxed";
}
// Override for MSL-specific extension syntax instructions
void CompilerMSL::emit_glsl_op(uint32_t result_type, uint32_t id, uint32_t eop, const uint32_t *args, uint32_t count)
{
GLSLstd450 op = static_cast<GLSLstd450>(eop);
switch (op)
{
case GLSLstd450Atan2:
emit_binary_func_op(result_type, id, args[0], args[1], "atan2");
break;
case GLSLstd450InverseSqrt:
emit_unary_func_op(result_type, id, args[0], "rsqrt");
break;
case GLSLstd450RoundEven:
emit_unary_func_op(result_type, id, args[0], "rint");
break;
case GLSLstd450FindSMsb:
emit_unary_func_op(result_type, id, args[0], "findSMSB");
break;
case GLSLstd450FindUMsb:
emit_unary_func_op(result_type, id, args[0], "findUMSB");
break;
case GLSLstd450PackSnorm4x8:
emit_unary_func_op(result_type, id, args[0], "pack_float_to_snorm4x8");
break;
case GLSLstd450PackUnorm4x8:
emit_unary_func_op(result_type, id, args[0], "pack_float_to_unorm4x8");
break;
case GLSLstd450PackSnorm2x16:
emit_unary_func_op(result_type, id, args[0], "pack_float_to_snorm2x16");
break;
case GLSLstd450PackUnorm2x16:
emit_unary_func_op(result_type, id, args[0], "pack_float_to_unorm2x16");
break;
case GLSLstd450PackHalf2x16:
{
auto expr = join("as_type<uint>(half2(", to_expression(args[0]), "))");
emit_op(result_type, id, expr, should_forward(args[0]));
inherit_expression_dependencies(id, args[0]);
break;
}
case GLSLstd450UnpackSnorm4x8:
emit_unary_func_op(result_type, id, args[0], "unpack_snorm4x8_to_float");
break;
case GLSLstd450UnpackUnorm4x8:
emit_unary_func_op(result_type, id, args[0], "unpack_unorm4x8_to_float");
break;
case GLSLstd450UnpackSnorm2x16:
emit_unary_func_op(result_type, id, args[0], "unpack_snorm2x16_to_float");
break;
case GLSLstd450UnpackUnorm2x16:
emit_unary_func_op(result_type, id, args[0], "unpack_unorm2x16_to_float");
break;
case GLSLstd450UnpackHalf2x16:
{
auto expr = join("float2(as_type<half2>(", to_expression(args[0]), "))");
emit_op(result_type, id, expr, should_forward(args[0]));
inherit_expression_dependencies(id, args[0]);
break;
}
case GLSLstd450PackDouble2x32:
emit_unary_func_op(result_type, id, args[0], "unsupported_GLSLstd450PackDouble2x32"); // Currently unsupported
break;
case GLSLstd450UnpackDouble2x32:
emit_unary_func_op(result_type, id, args[0], "unsupported_GLSLstd450UnpackDouble2x32"); // Currently unsupported
break;
case GLSLstd450MatrixInverse:
{
auto &mat_type = get<SPIRType>(result_type);
switch (mat_type.columns)
{
case 2:
emit_unary_func_op(result_type, id, args[0], "spvInverse2x2");
break;
case 3:
emit_unary_func_op(result_type, id, args[0], "spvInverse3x3");
break;
case 4:
emit_unary_func_op(result_type, id, args[0], "spvInverse4x4");
break;
default:
break;
}
break;
}
case GLSLstd450FMin:
// If the result type isn't float, don't bother calling the specific
// precise::/fast:: version. Metal doesn't have those for half and
// double types.
if (get<SPIRType>(result_type).basetype != SPIRType::Float)
emit_binary_func_op(result_type, id, args[0], args[1], "min");
else
emit_binary_func_op(result_type, id, args[0], args[1], "fast::min");
break;
case GLSLstd450FMax:
if (get<SPIRType>(result_type).basetype != SPIRType::Float)
emit_binary_func_op(result_type, id, args[0], args[1], "max");
else
emit_binary_func_op(result_type, id, args[0], args[1], "fast::max");
break;
case GLSLstd450FClamp:
// TODO: If args[1] is 0 and args[2] is 1, emit a saturate() call.
if (get<SPIRType>(result_type).basetype != SPIRType::Float)
emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "clamp");
else
emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "fast::clamp");
break;
case GLSLstd450NMin:
if (get<SPIRType>(result_type).basetype != SPIRType::Float)
emit_binary_func_op(result_type, id, args[0], args[1], "min");
else
emit_binary_func_op(result_type, id, args[0], args[1], "precise::min");
break;
case GLSLstd450NMax:
if (get<SPIRType>(result_type).basetype != SPIRType::Float)
emit_binary_func_op(result_type, id, args[0], args[1], "max");
else
emit_binary_func_op(result_type, id, args[0], args[1], "precise::max");
break;
case GLSLstd450NClamp:
// TODO: If args[1] is 0 and args[2] is 1, emit a saturate() call.
if (get<SPIRType>(result_type).basetype != SPIRType::Float)
emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "clamp");
else
emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "precise::clamp");
break;
// TODO:
// GLSLstd450InterpolateAtCentroid (centroid_no_perspective qualifier)
// GLSLstd450InterpolateAtSample (sample_no_perspective qualifier)
// GLSLstd450InterpolateAtOffset
default:
CompilerGLSL::emit_glsl_op(result_type, id, eop, args, count);
break;
}
}
// Emit a structure declaration for the specified interface variable.
void CompilerMSL::emit_interface_block(uint32_t ib_var_id)
{
if (ib_var_id)
{
auto &ib_var = get<SPIRVariable>(ib_var_id);
auto &ib_type = get<SPIRType>(ib_var.basetype);
auto &m = meta.at(ib_type.self);
if (m.members.size() > 0)
emit_struct(ib_type);
}
}
// Emits the declaration signature of the specified function.
// If this is the entry point function, Metal-specific return value and function arguments are added.
void CompilerMSL::emit_function_prototype(SPIRFunction &func, const Bitset &)
{
if (func.self != entry_point)
add_function_overload(func);
local_variable_names = resource_names;
string decl;
processing_entry_point = (func.self == entry_point);
auto &type = get<SPIRType>(func.return_type);
if (type.array.empty())
{
decl += func_type_decl(type);
}
else
{
// We cannot return arrays in MSL, so "return" through an out variable.
decl = "void";
}
decl += " ";
decl += to_name(func.self);
decl += "(";
if (!type.array.empty())
{
// Fake arrays returns by writing to an out array instead.
decl += "thread ";
decl += type_to_glsl(type);
decl += " (&SPIRV_Cross_return_value)";
decl += type_to_array_glsl(type);
if (!func.arguments.empty())
decl += ", ";
}
if (processing_entry_point)
{
decl += entry_point_args(!func.arguments.empty());
// If entry point function has variables that require early declaration,
// ensure they each have an empty initializer, creating one if needed.
// This is done at this late stage because the initialization expression
// is cleared after each compilation pass.
for (auto var_id : vars_needing_early_declaration)
{
auto &ed_var = get<SPIRVariable>(var_id);
if (!ed_var.initializer)
ed_var.initializer = increase_bound_by(1);
set<SPIRExpression>(ed_var.initializer, "{}", ed_var.basetype, true);
}
}
for (auto &arg : func.arguments)
{
uint32_t name_id = arg.id;
string address_space;
auto *var = maybe_get<SPIRVariable>(arg.id);
if (var)
{
// If we need to modify the name of the variable, make sure we modify the original variable.
// Our alias is just a shadow variable.
if (arg.alias_global_variable && var->basevariable)
name_id = var->basevariable;
var->parameter = &arg; // Hold a pointer to the parameter so we can invalidate the readonly field if needed.
address_space = get_argument_address_space(*var);
}
add_local_variable_name(name_id);
if (!address_space.empty())
decl += address_space + " ";
decl += argument_decl(arg);
// Manufacture automatic sampler arg for SampledImage texture
auto &arg_type = get<SPIRType>(arg.type);
if (arg_type.basetype == SPIRType::SampledImage && arg_type.image.dim != DimBuffer)
decl += join(", thread const ", sampler_type(arg_type), " ", to_sampler_expression(arg.id));
if (&arg != &func.arguments.back())
decl += ", ";
}
decl += ")";
statement(decl);
}
// Returns the texture sampling function string for the specified image and sampling characteristics.
string CompilerMSL::to_function_name(uint32_t img, const SPIRType &, bool is_fetch, bool is_gather, bool, bool, bool,
bool, bool has_dref, uint32_t)
{
// Texture reference
string fname = to_expression(img) + ".";
// Texture function and sampler
if (is_fetch)
fname += "read";
else if (is_gather)
fname += "gather";
else
fname += "sample";
if (has_dref)
fname += "_compare";
return fname;
}
// Returns the function args for a texture sampling function for the specified image and sampling characteristics.
string CompilerMSL::to_function_args(uint32_t img, const SPIRType &imgtype, bool is_fetch, bool, bool is_proj,
uint32_t coord, uint32_t, uint32_t dref, uint32_t grad_x, uint32_t grad_y,
uint32_t lod, uint32_t coffset, uint32_t offset, uint32_t bias, uint32_t comp,
uint32_t sample, bool *p_forward)
{
string farg_str;
if (!is_fetch)
farg_str += to_sampler_expression(img);
// Texture coordinates
bool forward = should_forward(coord);
auto coord_expr = to_enclosed_expression(coord);
auto &coord_type = expression_type(coord);
bool coord_is_fp = type_is_floating_point(coord_type);
bool is_cube_fetch = false;
string tex_coords = coord_expr;
const char *alt_coord = "";
switch (imgtype.image.dim)
{
case Dim1D:
if (coord_type.vecsize > 1)
tex_coords += ".x";
if (is_fetch)
tex_coords = "uint(" + round_fp_tex_coords(tex_coords, coord_is_fp) + ")";
alt_coord = ".y";
break;
case DimBuffer:
if (coord_type.vecsize > 1)
tex_coords += ".x";
// Metal texel buffer textures are 2D, so convert 1D coord to 2D.
if (is_fetch)
tex_coords = "spvTexelBufferCoord(" + round_fp_tex_coords(tex_coords, coord_is_fp) + ")";
alt_coord = ".y";
break;
case DimSubpassData:
if (imgtype.image.ms)
tex_coords = "uint2(gl_FragCoord.xy)";
else
tex_coords = join("uint2(gl_FragCoord.xy), 0");
break;
case Dim2D:
if (coord_type.vecsize > 2)
tex_coords += ".xy";
if (is_fetch)
tex_coords = "uint2(" + round_fp_tex_coords(tex_coords, coord_is_fp) + ")";
alt_coord = ".z";
break;
case Dim3D:
if (coord_type.vecsize > 3)
tex_coords += ".xyz";
if (is_fetch)
tex_coords = "uint3(" + round_fp_tex_coords(tex_coords, coord_is_fp) + ")";
alt_coord = ".w";
break;
case DimCube:
if (is_fetch)
{
is_cube_fetch = true;
tex_coords += ".xy";
tex_coords = "uint2(" + round_fp_tex_coords(tex_coords, coord_is_fp) + ")";
}
else
{
if (coord_type.vecsize > 3)
tex_coords += ".xyz";
}
alt_coord = ".w";
break;
default:
break;
}
if (is_fetch && offset)
{
// Fetch offsets must be applied directly to the coordinate.
forward = forward && should_forward(offset);
auto &type = expression_type(offset);
if (type.basetype != SPIRType::UInt)
tex_coords += " + " + bitcast_expression(SPIRType::UInt, offset);
else
tex_coords += " + " + to_enclosed_expression(offset);
}
else if (is_fetch && coffset)
{
// Fetch offsets must be applied directly to the coordinate.
forward = forward && should_forward(coffset);
auto &type = expression_type(coffset);
if (type.basetype != SPIRType::UInt)
tex_coords += " + " + bitcast_expression(SPIRType::UInt, coffset);
else
tex_coords += " + " + to_enclosed_expression(coffset);
}
// If projection, use alt coord as divisor
if (is_proj)
tex_coords += " / " + coord_expr + alt_coord;
if (!farg_str.empty())
farg_str += ", ";
farg_str += tex_coords;
// If fetch from cube, add face explicitly
if (is_cube_fetch)
{
// Special case for cube arrays, face and layer are packed in one dimension.
if (imgtype.image.arrayed)
farg_str += ", uint(" + join(coord_expr, ".z) % 6u");
else
farg_str += ", uint(" + round_fp_tex_coords(coord_expr + ".z", coord_is_fp) + ")";
}
// If array, use alt coord
if (imgtype.image.arrayed)
{
// Special case for cube arrays, face and layer are packed in one dimension.
if (imgtype.image.dim == DimCube && is_fetch)
farg_str += ", uint(" + join(coord_expr, ".z) / 6u");
else
farg_str += ", uint(" + round_fp_tex_coords(coord_expr + alt_coord, coord_is_fp) + ")";
}
// Depth compare reference value
if (dref)
{
forward = forward && should_forward(dref);
farg_str += ", ";
farg_str += to_expression(dref);
}
// LOD Options
// Metal does not support LOD for 1D textures.
if (bias && imgtype.image.dim != Dim1D)
{
forward = forward && should_forward(bias);
farg_str += ", bias(" + to_expression(bias) + ")";
}
// Metal does not support LOD for 1D textures.
if (lod && imgtype.image.dim != Dim1D)
{
forward = forward && should_forward(lod);
if (is_fetch)
{
farg_str += ", " + to_expression(lod);
}
else
{
farg_str += ", level(" + to_expression(lod) + ")";
}
}
else if (is_fetch && !lod && imgtype.image.dim != Dim1D && imgtype.image.dim != DimBuffer && !imgtype.image.ms &&
imgtype.image.sampled != 2)
{
// Lod argument is optional in OpImageFetch, but we require a LOD value, pick 0 as the default.
// Check for sampled type as well, because is_fetch is also used for OpImageRead in MSL.
farg_str += ", 0";
}
// Metal does not support LOD for 1D textures.
if ((grad_x || grad_y) && imgtype.image.dim != Dim1D)
{
forward = forward && should_forward(grad_x);
forward = forward && should_forward(grad_y);
string grad_opt;
switch (imgtype.image.dim)
{
case Dim2D:
grad_opt = "2d";
break;
case Dim3D:
grad_opt = "3d";
break;
case DimCube:
grad_opt = "cube";
break;
default:
grad_opt = "unsupported_gradient_dimension";
break;
}
farg_str += ", gradient" + grad_opt + "(" + to_expression(grad_x) + ", " + to_expression(grad_y) + ")";
}
// Add offsets
string offset_expr;
if (coffset && !is_fetch)
{
forward = forward && should_forward(coffset);
offset_expr = to_expression(coffset);
}
else if (offset && !is_fetch)
{
forward = forward && should_forward(offset);
offset_expr = to_expression(offset);
}
if (!offset_expr.empty())
{
switch (imgtype.image.dim)
{
case Dim2D:
if (coord_type.vecsize > 2)
offset_expr = enclose_expression(offset_expr) + ".xy";
farg_str += ", " + offset_expr;
break;
case Dim3D:
if (coord_type.vecsize > 3)
offset_expr = enclose_expression(offset_expr) + ".xyz";
farg_str += ", " + offset_expr;
break;
default:
break;
}
}
if (comp)
{
// If 2D has gather component, ensure it also has an offset arg
if (imgtype.image.dim == Dim2D && offset_expr.empty())
farg_str += ", int2(0)";
forward = forward && should_forward(comp);
farg_str += ", " + to_component_argument(comp);
}
if (sample)
{
farg_str += ", ";
farg_str += to_expression(sample);
}
*p_forward = forward;
return farg_str;
}
// If the texture coordinates are floating point, invokes MSL round() function to round them.
string CompilerMSL::round_fp_tex_coords(string tex_coords, bool coord_is_fp)
{
return coord_is_fp ? ("round(" + tex_coords + ")") : tex_coords;
}
// Returns a string to use in an image sampling function argument.
// The ID must be a scalar constant.
string CompilerMSL::to_component_argument(uint32_t id)
{
if (ids[id].get_type() != TypeConstant)
{
SPIRV_CROSS_THROW("ID " + to_string(id) + " is not an OpConstant.");
return "component::x";
}
uint32_t component_index = get<SPIRConstant>(id).scalar();
switch (component_index)
{
case 0:
return "component::x";
case 1:
return "component::y";
case 2:
return "component::z";
case 3:
return "component::w";
default:
SPIRV_CROSS_THROW("The value (" + to_string(component_index) + ") of OpConstant ID " + to_string(id) +
" is not a valid Component index, which must be one of 0, 1, 2, or 3.");
return "component::x";
}
}
// Establish sampled image as expression object and assign the sampler to it.
void CompilerMSL::emit_sampled_image_op(uint32_t result_type, uint32_t result_id, uint32_t image_id, uint32_t samp_id)
{
set<SPIRExpression>(result_id, to_expression(image_id), result_type, true);
meta[result_id].sampler = samp_id;
}
// Returns a string representation of the ID, usable as a function arg.
// Manufacture automatic sampler arg for SampledImage texture.
string CompilerMSL::to_func_call_arg(uint32_t id)
{
string arg_str = CompilerGLSL::to_func_call_arg(id);
// Manufacture automatic sampler arg if the arg is a SampledImage texture.
auto &type = expression_type(id);
if (type.basetype == SPIRType::SampledImage && type.image.dim != DimBuffer)
arg_str += ", " + to_sampler_expression(id);
return arg_str;
}
// If the ID represents a sampled image that has been assigned a sampler already,
// generate an expression for the sampler, otherwise generate a fake sampler name
// by appending a suffix to the expression constructed from the ID.
string CompilerMSL::to_sampler_expression(uint32_t id)
{
auto expr = to_expression(id);
auto index = expr.find_first_of('[');
uint32_t samp_id = meta[id].sampler;
if (index == string::npos)
return samp_id ? to_expression(samp_id) : expr + sampler_name_suffix;
else
{
auto image_expr = expr.substr(0, index);
auto array_expr = expr.substr(index);
return samp_id ? to_expression(samp_id) : (image_expr + sampler_name_suffix + array_expr);
}
}
// Checks whether the ID is a row_major matrix that requires conversion before use
bool CompilerMSL::is_non_native_row_major_matrix(uint32_t id)
{
// Natively supported row-major matrices do not need to be converted.
if (backend.native_row_major_matrix)
return false;
// Non-matrix or column-major matrix types do not need to be converted.
if (!meta[id].decoration.decoration_flags.get(DecorationRowMajor))
return false;
// Generate a function that will swap matrix elements from row-major to column-major.
// Packed row-matrix should just use transpose() function.
if (!has_decoration(id, DecorationCPacked))
{
const auto type = expression_type(id);
add_convert_row_major_matrix_function(type.columns, type.vecsize);
}
return true;
}
// Checks whether the member is a row_major matrix that requires conversion before use
bool CompilerMSL::member_is_non_native_row_major_matrix(const SPIRType &type, uint32_t index)
{
// Natively supported row-major matrices do not need to be converted.
if (backend.native_row_major_matrix)
return false;
// Non-matrix or column-major matrix types do not need to be converted.
if (!combined_decoration_for_member(type, index).get(DecorationRowMajor))
return false;
// Generate a function that will swap matrix elements from row-major to column-major.
// Packed row-matrix should just use transpose() function.
if (!has_member_decoration(type.self, index, DecorationCPacked))
{
const auto mbr_type = get<SPIRType>(type.member_types[index]);
add_convert_row_major_matrix_function(mbr_type.columns, mbr_type.vecsize);
}
return true;
}
// Adds a function suitable for converting a non-square row-major matrix to a column-major matrix.
void CompilerMSL::add_convert_row_major_matrix_function(uint32_t cols, uint32_t rows)
{
SPVFuncImpl spv_func;
if (cols == rows) // Square matrix...just use transpose() function
return;
else if (cols == 2 && rows == 3)
spv_func = SPVFuncImplRowMajor2x3;
else if (cols == 2 && rows == 4)
spv_func = SPVFuncImplRowMajor2x4;
else if (cols == 3 && rows == 2)
spv_func = SPVFuncImplRowMajor3x2;
else if (cols == 3 && rows == 4)
spv_func = SPVFuncImplRowMajor3x4;
else if (cols == 4 && rows == 2)
spv_func = SPVFuncImplRowMajor4x2;
else if (cols == 4 && rows == 3)
spv_func = SPVFuncImplRowMajor4x3;
else
SPIRV_CROSS_THROW("Could not convert row-major matrix.");
auto rslt = spv_function_implementations.insert(spv_func);
if (rslt.second)
{
add_pragma_line("#pragma clang diagnostic ignored \"-Wmissing-prototypes\"");
force_recompile = true;
}
}
// Wraps the expression string in a function call that converts the
// row_major matrix result of the expression to a column_major matrix.
string CompilerMSL::convert_row_major_matrix(string exp_str, const SPIRType &exp_type, bool is_packed)
{
strip_enclosed_expression(exp_str);
string func_name;
// Square and packed matrices can just use transpose
if (exp_type.columns == exp_type.vecsize || is_packed)
func_name = "transpose";
else
func_name = string("spvConvertFromRowMajor") + to_string(exp_type.columns) + "x" + to_string(exp_type.vecsize);
return join(func_name, "(", exp_str, ")");
}
// Called automatically at the end of the entry point function
void CompilerMSL::emit_fixup()
{
if ((get_entry_point().model == ExecutionModelVertex) && stage_out_var_id && !qual_pos_var_name.empty())
{
if (options.vertex.fixup_clipspace)
statement(qual_pos_var_name, ".z = (", qual_pos_var_name, ".z + ", qual_pos_var_name,
".w) * 0.5; // Adjust clip-space for Metal");
if (options.vertex.flip_vert_y)
statement(qual_pos_var_name, ".y = -(", qual_pos_var_name, ".y);", " // Invert Y-axis for Metal");
}
}
// Emit a structure member, padding and packing to maintain the correct memeber alignments.
void CompilerMSL::emit_struct_member(const SPIRType &type, uint32_t member_type_id, uint32_t index,
const string &qualifier, uint32_t)
{
auto &membertype = get<SPIRType>(member_type_id);
// If this member requires padding to maintain alignment, emit a dummy padding member.
MSLStructMemberKey key = get_struct_member_key(type.self, index);
uint32_t pad_len = struct_member_padding[key];
if (pad_len > 0)
statement("char pad", to_string(index), "[", to_string(pad_len), "];");
// If this member is packed, mark it as so.
string pack_pfx = "";
if (member_is_packed_type(type, index))
{
pack_pfx = "packed_";
// If we're packing a matrix, output an appropriate typedef
if (membertype.vecsize > 1 && membertype.columns > 1)
{
string base_type = membertype.width == 16 ? "half" : "float";
string td_line = "typedef ";
td_line += base_type + to_string(membertype.vecsize) + "x" + to_string(membertype.columns);
td_line += " " + pack_pfx;
td_line += base_type + to_string(membertype.columns) + "x" + to_string(membertype.vecsize);
td_line += ";";
add_typedef_line(td_line);
}
}
statement(pack_pfx, type_to_glsl(membertype), " ", qualifier, to_member_name(type, index),
member_attribute_qualifier(type, index), type_to_array_glsl(membertype), ";");
}
// Return a MSL qualifier for the specified function attribute member
string CompilerMSL::member_attribute_qualifier(const SPIRType &type, uint32_t index)
{
auto &execution = get_entry_point();
uint32_t mbr_type_id = type.member_types[index];
auto &mbr_type = get<SPIRType>(mbr_type_id);
BuiltIn builtin;
bool is_builtin = is_member_builtin(type, index, &builtin);
// Vertex function inputs
if (execution.model == ExecutionModelVertex && type.storage == StorageClassInput)
{
if (is_builtin)
{
switch (builtin)
{
case BuiltInVertexId:
case BuiltInVertexIndex:
case BuiltInBaseVertex:
case BuiltInInstanceId:
case BuiltInInstanceIndex:
case BuiltInBaseInstance:
return string(" [[") + builtin_qualifier(builtin) + "]]";
case BuiltInDrawIndex:
SPIRV_CROSS_THROW("DrawIndex is not supported in MSL.");
default:
return "";
}
}
uint32_t locn = get_ordered_member_location(type.self, index);
if (locn != k_unknown_location)
return string(" [[attribute(") + convert_to_string(locn) + ")]]";
}
// Vertex function outputs
if (execution.model == ExecutionModelVertex && type.storage == StorageClassOutput)
{
if (is_builtin)
{
switch (builtin)
{
case BuiltInPointSize:
// Only mark the PointSize builtin if really rendering points.
// Some shaders may include a PointSize builtin even when used to render
// non-point topologies, and Metal will reject this builtin when compiling
// the shader into a render pipeline that uses a non-point topology.
return msl_options.enable_point_size_builtin ? (string(" [[") + builtin_qualifier(builtin) + "]]") : "";
case BuiltInPosition:
case BuiltInLayer:
case BuiltInClipDistance:
return string(" [[") + builtin_qualifier(builtin) + "]]" + (mbr_type.array.empty() ? "" : " ");
default:
return "";
}
}
uint32_t comp;
uint32_t locn = get_ordered_member_location(type.self, index, &comp);
if (locn != k_unknown_location)
{
if (comp != k_unknown_component)
return string(" [[user(locn") + convert_to_string(locn) + "_" + convert_to_string(comp) + ")]]";
else
return string(" [[user(locn") + convert_to_string(locn) + ")]]";
}
}
// Fragment function inputs
if (execution.model == ExecutionModelFragment && type.storage == StorageClassInput)
{
string quals = "";
if (is_builtin)
{
switch (builtin)
{
case BuiltInFrontFacing:
case BuiltInPointCoord:
case BuiltInFragCoord:
case BuiltInSampleId:
case BuiltInSampleMask:
case BuiltInLayer:
quals = builtin_qualifier(builtin);
default:
break;
}
}
else
{
uint32_t comp;
uint32_t locn = get_ordered_member_location(type.self, index, &comp);
if (locn != k_unknown_location)
{
if (comp != k_unknown_component)
quals = string("user(locn") + convert_to_string(locn) + "_" + convert_to_string(comp) + ")";
else
quals = string("user(locn") + convert_to_string(locn) + ")";
}
}
// Don't bother decorating integers with the 'flat' attribute; it's
// the default (in fact, the only option). Also don't bother with the
// FragCoord builtin; it's always noperspective on Metal.
if (!type_is_integral(mbr_type) && (!is_builtin || builtin != BuiltInFragCoord))
{
if (has_member_decoration(type.self, index, DecorationFlat))
{
if (!quals.empty())
quals += ", ";
quals += "flat";
}
else if (has_member_decoration(type.self, index, DecorationCentroid))
{
if (!quals.empty())
quals += ", ";
if (has_member_decoration(type.self, index, DecorationNoPerspective))
quals += "centroid_no_perspective";
else
quals += "centroid_perspective";
}
else if (has_member_decoration(type.self, index, DecorationSample))
{
if (!quals.empty())
quals += ", ";
if (has_member_decoration(type.self, index, DecorationNoPerspective))
quals += "sample_no_perspective";
else
quals += "sample_perspective";
}
else if (has_member_decoration(type.self, index, DecorationNoPerspective))
{
if (!quals.empty())
quals += ", ";
quals += "center_no_perspective";
}
}
if (!quals.empty())
return " [[" + quals + "]]";
}
// Fragment function outputs
if (execution.model == ExecutionModelFragment && type.storage == StorageClassOutput)
{
if (is_builtin)
{
switch (builtin)
{
case BuiltInSampleMask:
case BuiltInFragDepth:
return string(" [[") + builtin_qualifier(builtin) + "]]";
default:
return "";
}
}
uint32_t locn = get_ordered_member_location(type.self, index);
if (locn != k_unknown_location && has_member_decoration(type.self, index, DecorationIndex))
return join(" [[color(", locn, "), index(", get_member_decoration(type.self, index, DecorationIndex),
")]]");
else if (locn != k_unknown_location)
return join(" [[color(", locn, ")]]");
else if (has_member_decoration(type.self, index, DecorationIndex))
return join(" [[index(", get_member_decoration(type.self, index, DecorationIndex), ")]]");
else
return "";
}
// Compute function inputs
if (execution.model == ExecutionModelGLCompute && type.storage == StorageClassInput)
{
if (is_builtin)
{
switch (builtin)
{
case BuiltInGlobalInvocationId:
case BuiltInWorkgroupId:
case BuiltInNumWorkgroups:
case BuiltInLocalInvocationId:
case BuiltInLocalInvocationIndex:
return string(" [[") + builtin_qualifier(builtin) + "]]";
default:
return "";
}
}
}
return "";
}
// Returns the location decoration of the member with the specified index in the specified type.
// If the location of the member has been explicitly set, that location is used. If not, this
// function assumes the members are ordered in their location order, and simply returns the
// index as the location.
uint32_t CompilerMSL::get_ordered_member_location(uint32_t type_id, uint32_t index, uint32_t *comp)
{
auto &m = meta.at(type_id);
if (index < m.members.size())
{
auto &dec = m.members[index];
if (comp)
{
if (dec.decoration_flags.get(DecorationComponent))
*comp = dec.component;
else
*comp = k_unknown_component;
}
if (dec.decoration_flags.get(DecorationLocation))
return dec.location;
}
return index;
}
// Returns the type declaration for a function, including the
// entry type if the current function is the entry point function
string CompilerMSL::func_type_decl(SPIRType &type)
{
// The regular function return type. If not processing the entry point function, that's all we need
string return_type = type_to_glsl(type) + type_to_array_glsl(type);
if (!processing_entry_point)
return return_type;
// If an outgoing interface block has been defined, and it should be returned, override the entry point return type
bool ep_should_return_output = !get_is_rasterization_disabled();
if (stage_out_var_id && ep_should_return_output)
{
auto &so_var = get<SPIRVariable>(stage_out_var_id);
auto &so_type = get<SPIRType>(so_var.basetype);
return_type = type_to_glsl(so_type) + type_to_array_glsl(type);
}
// Prepend a entry type, based on the execution model
string entry_type;
auto &execution = get_entry_point();
switch (execution.model)
{
case ExecutionModelVertex:
entry_type = "vertex";
break;
case ExecutionModelFragment:
entry_type =
execution.flags.get(ExecutionModeEarlyFragmentTests) ? "fragment [[ early_fragment_tests ]]" : "fragment";
break;
case ExecutionModelGLCompute:
case ExecutionModelKernel:
entry_type = "kernel";
break;
default:
entry_type = "unknown";
break;
}
return entry_type + " " + return_type;
}
// In MSL, address space qualifiers are required for all pointer or reference arguments
string CompilerMSL::get_argument_address_space(const SPIRVariable &argument)
{
const auto &type = get<SPIRType>(argument.basetype);
switch (type.storage)
{
case StorageClassWorkgroup:
return "threadgroup";
case StorageClassStorageBuffer:
{
bool readonly = get_buffer_block_flags(argument).get(DecorationNonWritable);
return readonly ? "const device" : "device";
}
case StorageClassUniform:
case StorageClassUniformConstant:
case StorageClassPushConstant:
if (type.basetype == SPIRType::Struct)
{
bool ssbo = has_decoration(type.self, DecorationBufferBlock);
if (ssbo)
{
bool readonly = get_buffer_block_flags(argument).get(DecorationNonWritable);
return readonly ? "const device" : "device";
}
else
return "constant";
}
break;
case StorageClassFunction:
case StorageClassGeneric:
// No address space for plain values.
return type.pointer ? "thread" : "";
default:
break;
}
return "thread";
}
// Returns a string containing a comma-delimited list of args for the entry point function
string CompilerMSL::entry_point_args(bool append_comma)
{
string ep_args;
// Stage-in structure
if (stage_in_var_id)
{
auto &var = get<SPIRVariable>(stage_in_var_id);
auto &type = get<SPIRType>(var.basetype);
if (!ep_args.empty())
ep_args += ", ";
ep_args += type_to_glsl(type) + " " + to_name(var.self) + " [[stage_in]]";
}
// Output resources, sorted by resource index & type
// We need to sort to work around a bug on macOS 10.13 with NVidia drivers where switching between shaders
// with different order of buffers can result in issues with buffer assignments inside the driver.
struct Resource
{
Variant *id;
string name;
SPIRType::BaseType basetype;
uint32_t index;
};
vector<Resource> resources;
for (auto &id : ids)
{
if (id.get_type() == TypeVariable)
{
auto &var = id.get<SPIRVariable>();
auto &type = get<SPIRType>(var.basetype);
uint32_t var_id = var.self;
if ((var.storage == StorageClassUniform || var.storage == StorageClassUniformConstant ||
var.storage == StorageClassPushConstant || var.storage == StorageClassStorageBuffer) &&
!is_hidden_variable(var))
{
if (type.basetype == SPIRType::SampledImage)
{
resources.push_back(
{ &id, to_name(var_id), SPIRType::Image, get_metal_resource_index(var, SPIRType::Image) });
if (type.image.dim != DimBuffer && constexpr_samplers.count(var_id) == 0)
{
resources.push_back({ &id, to_sampler_expression(var_id), SPIRType::Sampler,
get_metal_resource_index(var, SPIRType::Sampler) });
}
}
else if (constexpr_samplers.count(var_id) == 0)
{
// constexpr samplers are not declared as resources.
resources.push_back(
{ &id, to_name(var_id), type.basetype, get_metal_resource_index(var, type.basetype) });
}
}
}
}
std::sort(resources.begin(), resources.end(), [](const Resource &lhs, const Resource &rhs) {
return tie(lhs.basetype, lhs.index) < tie(rhs.basetype, rhs.index);
});
for (auto &r : resources)
{
auto &var = r.id->get<SPIRVariable>();
auto &type = get<SPIRType>(var.basetype);
uint32_t var_id = var.self;
switch (r.basetype)
{
case SPIRType::Struct:
{
auto &m = meta.at(type.self);
if (m.members.size() == 0)
break;
if (!ep_args.empty())
ep_args += ", ";
ep_args += get_argument_address_space(var) + " " + type_to_glsl(type) + "& " + r.name;
ep_args += " [[buffer(" + convert_to_string(r.index) + ")]]";
break;
}
case SPIRType::Sampler:
if (!ep_args.empty())
ep_args += ", ";
ep_args += sampler_type(type) + " " + r.name;
ep_args += " [[sampler(" + convert_to_string(r.index) + ")]]";
break;
case SPIRType::Image:
if (!ep_args.empty())
ep_args += ", ";
ep_args += image_type_glsl(type, var_id) + " " + r.name;
ep_args += " [[texture(" + convert_to_string(r.index) + ")]]";
break;
default:
SPIRV_CROSS_THROW("Unexpected resource type");
break;
}
}
// Builtin variables
for (auto &id : ids)
{
if (id.get_type() == TypeVariable)
{
auto &var = id.get<SPIRVariable>();
uint32_t var_id = var.self;
if (var.storage == StorageClassInput && is_builtin_variable(var))
{
if (!ep_args.empty())
ep_args += ", ";
BuiltIn bi_type = meta[var_id].decoration.builtin_type;
ep_args += builtin_type_decl(bi_type) + " " + to_expression(var_id);
ep_args += " [[" + builtin_qualifier(bi_type) + "]]";
}
}
}
// Vertex and instance index built-ins
if (needs_vertex_idx_arg)
ep_args += built_in_func_arg(BuiltInVertexIndex, !ep_args.empty());
if (needs_instance_idx_arg)
ep_args += built_in_func_arg(BuiltInInstanceIndex, !ep_args.empty());
if (!ep_args.empty() && append_comma)
ep_args += ", ";
return ep_args;
}
// Returns the Metal index of the resource of the specified type as used by the specified variable.
uint32_t CompilerMSL::get_metal_resource_index(SPIRVariable &var, SPIRType::BaseType basetype)
{
auto &execution = get_entry_point();
auto &var_dec = meta[var.self].decoration;
uint32_t var_desc_set = (var.storage == StorageClassPushConstant) ? kPushConstDescSet : var_dec.set;
uint32_t var_binding = (var.storage == StorageClassPushConstant) ? kPushConstBinding : var_dec.binding;
// If a matching binding has been specified, find and use it
for (auto p_res_bind : resource_bindings)
{
if (p_res_bind->stage == execution.model && p_res_bind->desc_set == var_desc_set &&
p_res_bind->binding == var_binding)
{
p_res_bind->used_by_shader = true;
switch (basetype)
{
case SPIRType::Struct:
return p_res_bind->msl_buffer;
case SPIRType::Image:
return p_res_bind->msl_texture;
case SPIRType::Sampler:
return p_res_bind->msl_sampler;
default:
return 0;
}
}
}
// If there is no explicit mapping of bindings to MSL, use the declared binding.
if (has_decoration(var.self, DecorationBinding))
return get_decoration(var.self, DecorationBinding);
uint32_t binding_stride = 1;
auto &type = get<SPIRType>(var.basetype);
for (uint32_t i = 0; i < uint32_t(type.array.size()); i++)
binding_stride *= type.array_size_literal[i] ? type.array[i] : get<SPIRConstant>(type.array[i]).scalar();
// If a binding has not been specified, revert to incrementing resource indices
uint32_t resource_index;
switch (basetype)
{
case SPIRType::Struct:
resource_index = next_metal_resource_index.msl_buffer;
next_metal_resource_index.msl_buffer += binding_stride;
break;
case SPIRType::Image:
resource_index = next_metal_resource_index.msl_texture;
next_metal_resource_index.msl_texture += binding_stride;
break;
case SPIRType::Sampler:
resource_index = next_metal_resource_index.msl_sampler;
next_metal_resource_index.msl_sampler += binding_stride;
break;
default:
resource_index = 0;
break;
}
return resource_index;
}
string CompilerMSL::argument_decl(const SPIRFunction::Parameter &arg)
{
auto &var = get<SPIRVariable>(arg.id);
auto &type = expression_type(arg.id);
// If we need to modify the name of the variable, make sure we use the original variable.
// Our alias is just a shadow variable.
uint32_t name_id = var.self;
if (arg.alias_global_variable && var.basevariable)
name_id = var.basevariable;
bool constref = !arg.alias_global_variable && type.pointer && arg.write_count == 0;
bool type_is_image = type.basetype == SPIRType::Image || type.basetype == SPIRType::SampledImage ||
type.basetype == SPIRType::Sampler;
// Arrays of images/samplers in MSL are always const.
if (!type.array.empty() && type_is_image)
constref = true;
string decl;
if (constref)
decl += "const ";
bool builtin = is_builtin_variable(var);
if (builtin)
decl += builtin_type_decl(static_cast<BuiltIn>(get_decoration(arg.id, DecorationBuiltIn)));
else
decl += type_to_glsl(type, arg.id);
bool opaque_handle = type.storage == StorageClassUniformConstant;
if (!builtin && !opaque_handle && !type.pointer &&
(type.storage == StorageClassFunction || type.storage == StorageClassGeneric))
{
// If the argument is a pure value and not an opaque type, we will pass by value.
decl += " ";
decl += to_expression(name_id);
}
else if (is_array(type) && !type_is_image)
{
// Arrays of images and samplers are special cased.
decl += " (&";
decl += to_expression(name_id);
decl += ")";
decl += type_to_array_glsl(type);
}
else if (!opaque_handle)
{
decl += "&";
decl += " ";
decl += to_expression(name_id);
}
else
{
decl += " ";
decl += to_expression(name_id);
}
return decl;
}
// If we're currently in the entry point function, and the object
// has a qualified name, use it, otherwise use the standard name.
string CompilerMSL::to_name(uint32_t id, bool allow_alias) const
{
if (current_function && (current_function->self == entry_point))
{
string qual_name = meta.at(id).decoration.qualified_alias;
if (!qual_name.empty())
return qual_name;
}
return Compiler::to_name(id, allow_alias);
}
// Returns a name that combines the name of the struct with the name of the member, except for Builtins
string CompilerMSL::to_qualified_member_name(const SPIRType &type, uint32_t index)
{
// Don't qualify Builtin names because they are unique and are treated as such when building expressions
BuiltIn builtin;
if (is_member_builtin(type, index, &builtin))
return builtin_to_glsl(builtin, type.storage);
// Strip any underscore prefix from member name
string mbr_name = to_member_name(type, index);
size_t startPos = mbr_name.find_first_not_of("_");
mbr_name = (startPos != string::npos) ? mbr_name.substr(startPos) : "";
return join(to_name(type.self), "_", mbr_name);
}
// Ensures that the specified name is permanently usable by prepending a prefix
// if the first chars are _ and a digit, which indicate a transient name.
string CompilerMSL::ensure_valid_name(string name, string pfx)
{
return (name.size() >= 2 && name[0] == '_' && isdigit(name[1])) ? (pfx + name) : name;
}
// Replace all names that match MSL keywords or Metal Standard Library functions.
void CompilerMSL::replace_illegal_names()
{
// FIXME: MSL and GLSL are doing two different things here.
// Agree on convention and remove this override.
static const unordered_set<string> keywords = {
"kernel", "vertex", "fragment", "compute", "bias",
};
static const unordered_set<string> illegal_func_names = {
"main",
"saturate",
};
for (auto &id : ids)
{
switch (id.get_type())
{
case TypeVariable:
{
auto &dec = meta[id.get_id()].decoration;
if (keywords.find(dec.alias) != end(keywords))
dec.alias += "0";
break;
}
case TypeFunction:
{
auto &dec = meta[id.get_id()].decoration;
if (illegal_func_names.find(dec.alias) != end(illegal_func_names))
dec.alias += "0";
break;
}
case TypeType:
{
for (auto &mbr_dec : meta[id.get_id()].members)
if (keywords.find(mbr_dec.alias) != end(keywords))
mbr_dec.alias += "0";
break;
}
default:
break;
}
}
for (auto &entry : entry_points)
{
// Change both the entry point name and the alias, to keep them synced.
string &ep_name = entry.second.name;
if (illegal_func_names.find(ep_name) != end(illegal_func_names))
ep_name += "0";
// Always write this because entry point might have been renamed earlier.
meta[entry.first].decoration.alias = ep_name;
}
CompilerGLSL::replace_illegal_names();
}
string CompilerMSL::to_qualifiers_glsl(uint32_t id)
{
string quals;
auto &type = expression_type(id);
if (type.storage == StorageClassWorkgroup)
quals += "threadgroup ";
return quals;
}
// The optional id parameter indicates the object whose type we are trying
// to find the description for. It is optional. Most type descriptions do not
// depend on a specific object's use of that type.
string CompilerMSL::type_to_glsl(const SPIRType &type, uint32_t id)
{
// Ignore the pointer type since GLSL doesn't have pointers.
string type_name;
switch (type.basetype)
{
case SPIRType::Struct:
// Need OpName lookup here to get a "sensible" name for a struct.
return to_name(type.self);
case SPIRType::Image:
case SPIRType::SampledImage:
return image_type_glsl(type, id);
case SPIRType::Sampler:
return sampler_type(type);
case SPIRType::Void:
return "void";
case SPIRType::AtomicCounter:
return "atomic_uint";
// Scalars
case SPIRType::Boolean:
type_name = "bool";
break;
case SPIRType::Char:
type_name = "char";
break;
case SPIRType::Int:
type_name = (type.width == 16 ? "short" : "int");
break;
case SPIRType::UInt:
type_name = (type.width == 16 ? "ushort" : "uint");
break;
case SPIRType::Int64:
type_name = "long"; // Currently unsupported
break;
case SPIRType::UInt64:
type_name = "size_t";
break;
case SPIRType::Half:
type_name = "half";
break;
case SPIRType::Float:
type_name = "float";
break;
case SPIRType::Double:
type_name = "double"; // Currently unsupported
break;
default:
return "unknown_type";
}
// Matrix?
if (type.columns > 1)
type_name += to_string(type.columns) + "x";
// Vector or Matrix?
if (type.vecsize > 1)
type_name += to_string(type.vecsize);
return type_name;
}
std::string CompilerMSL::sampler_type(const SPIRType &type)
{
if (!type.array.empty())
{
if (!msl_options.supports_msl_version(2))
SPIRV_CROSS_THROW("MSL 2.0 or greater is required for arrays of samplers.");
// Arrays of samplers in MSL must be declared with a special array<T, N> syntax ala C++11 std::array.
uint32_t array_size =
type.array_size_literal.back() ? type.array.back() : get<SPIRConstant>(type.array.back()).scalar();
if (array_size == 0)
SPIRV_CROSS_THROW("Unsized array of samplers is not supported in MSL.");
auto &parent = get<SPIRType>(get_non_pointer_type(type).parent_type);
return join("array<", sampler_type(parent), ", ", array_size, ">");
}
else
return "sampler";
}
// Returns an MSL string describing the SPIR-V image type
string CompilerMSL::image_type_glsl(const SPIRType &type, uint32_t id)
{
auto *var = maybe_get<SPIRVariable>(id);
if (var && var->basevariable)
{
// For comparison images, check against the base variable,
// and not the fake ID which might have been generated for this variable.
id = var->basevariable;
}
if (!type.array.empty())
{
if (!msl_options.supports_msl_version(2))
SPIRV_CROSS_THROW("MSL 2.0 or greater is required for arrays of textures.");
// Arrays of images in MSL must be declared with a special array<T, N> syntax ala C++11 std::array.
uint32_t array_size =
type.array_size_literal.back() ? type.array.back() : get<SPIRConstant>(type.array.back()).scalar();
if (array_size == 0)
SPIRV_CROSS_THROW("Unsized array of images is not supported in MSL.");
auto &parent = get<SPIRType>(get_non_pointer_type(type).parent_type);
return join("array<", image_type_glsl(parent, id), ", ", array_size, ">");
}
string img_type_name;
// Bypass pointers because we need the real image struct
auto &img_type = get<SPIRType>(type.self).image;
if (image_is_comparison(type, id))
{
switch (img_type.dim)
{
case Dim1D:
img_type_name += "depth1d_unsupported_by_metal";
break;
case Dim2D:
if (img_type.ms && img_type.arrayed)
{
if (!msl_options.supports_msl_version(2, 1))
SPIRV_CROSS_THROW("Multisampled array textures are supported from 2.1.");
img_type_name += "depth2d_ms_array";
}
else if (img_type.ms)
img_type_name += "depth2d_ms";
else if (img_type.arrayed)
img_type_name += "depth2d_array";
else
img_type_name += "depth2d";
break;
case Dim3D:
img_type_name += "depth3d_unsupported_by_metal";
break;
case DimCube:
img_type_name += (img_type.arrayed ? "depthcube_array" : "depthcube");
break;
default:
img_type_name += "unknown_depth_texture_type";
break;
}
}
else
{
switch (img_type.dim)
{
case Dim1D:
img_type_name += (img_type.arrayed ? "texture1d_array" : "texture1d");
break;
case DimBuffer:
case Dim2D:
case DimSubpassData:
if (img_type.ms && img_type.arrayed)
{
if (!msl_options.supports_msl_version(2, 1))
SPIRV_CROSS_THROW("Multisampled array textures are supported from 2.1.");
img_type_name += "texture2d_ms_array";
}
else if (img_type.ms)
img_type_name += "texture2d_ms";
else if (img_type.arrayed)
img_type_name += "texture2d_array";
else
img_type_name += "texture2d";
break;
case Dim3D:
img_type_name += "texture3d";
break;
case DimCube:
img_type_name += (img_type.arrayed ? "texturecube_array" : "texturecube");
break;
default:
img_type_name += "unknown_texture_type";
break;
}
}
// Append the pixel type
img_type_name += "<";
img_type_name += type_to_glsl(get<SPIRType>(img_type.type));
// For unsampled images, append the sample/read/write access qualifier.
// For kernel images, the access qualifier my be supplied directly by SPIR-V.
// Otherwise it may be set based on whether the image is read from or written to within the shader.
if (type.basetype == SPIRType::Image && type.image.sampled == 2 && type.image.dim != DimSubpassData)
{
switch (img_type.access)
{
case AccessQualifierReadOnly:
img_type_name += ", access::read";
break;
case AccessQualifierWriteOnly:
img_type_name += ", access::write";
break;
case AccessQualifierReadWrite:
img_type_name += ", access::read_write";
break;
default:
{
auto *p_var = maybe_get_backing_variable(id);
if (p_var && p_var->basevariable)
p_var = maybe_get<SPIRVariable>(p_var->basevariable);
if (p_var && !has_decoration(p_var->self, DecorationNonWritable))
{
img_type_name += ", access::";
if (!has_decoration(p_var->self, DecorationNonReadable))
img_type_name += "read_";
img_type_name += "write";
}
break;
}
}
}
img_type_name += ">";
return img_type_name;
}
string CompilerMSL::bitcast_glsl_op(const SPIRType &out_type, const SPIRType &in_type)
{
if ((out_type.basetype == SPIRType::UInt && in_type.basetype == SPIRType::Int) ||
(out_type.basetype == SPIRType::Int && in_type.basetype == SPIRType::UInt) ||
(out_type.basetype == SPIRType::UInt64 && in_type.basetype == SPIRType::Int64) ||
(out_type.basetype == SPIRType::Int64 && in_type.basetype == SPIRType::UInt64))
return type_to_glsl(out_type);
if ((out_type.basetype == SPIRType::UInt && in_type.basetype == SPIRType::Float) ||
(out_type.basetype == SPIRType::Int && in_type.basetype == SPIRType::Float) ||
(out_type.basetype == SPIRType::Float && in_type.basetype == SPIRType::UInt) ||
(out_type.basetype == SPIRType::Float && in_type.basetype == SPIRType::Int) ||
(out_type.basetype == SPIRType::Int64 && in_type.basetype == SPIRType::Double) ||
(out_type.basetype == SPIRType::UInt64 && in_type.basetype == SPIRType::Double) ||
(out_type.basetype == SPIRType::Double && in_type.basetype == SPIRType::Int64) ||
(out_type.basetype == SPIRType::Double && in_type.basetype == SPIRType::UInt64) ||
(out_type.basetype == SPIRType::Half && in_type.basetype == SPIRType::UInt) ||
(out_type.basetype == SPIRType::UInt && in_type.basetype == SPIRType::Half))
return "as_type<" + type_to_glsl(out_type) + ">";
return "";
}
// Returns an MSL string identifying the name of a SPIR-V builtin.
// Output builtins are qualified with the name of the stage out structure.
string CompilerMSL::builtin_to_glsl(BuiltIn builtin, StorageClass storage)
{
switch (builtin)
{
// Override GLSL compiler strictness
case BuiltInVertexId:
return "gl_VertexID";
case BuiltInInstanceId:
return "gl_InstanceID";
case BuiltInVertexIndex:
return "gl_VertexIndex";
case BuiltInInstanceIndex:
return "gl_InstanceIndex";
case BuiltInBaseVertex:
return "gl_BaseVertex";
case BuiltInBaseInstance:
return "gl_BaseInstance";
case BuiltInDrawIndex:
SPIRV_CROSS_THROW("DrawIndex is not supported in MSL.");
// When used in the entry function, output builtins are qualified with output struct name.
// Test storage class as NOT Input, as output builtins might be part of generic type.
case BuiltInPosition:
case BuiltInPointSize:
case BuiltInClipDistance:
case BuiltInCullDistance:
case BuiltInLayer:
case BuiltInFragDepth:
case BuiltInSampleMask:
if (storage != StorageClassInput && current_function && (current_function->self == entry_point))
return stage_out_var_name + "." + CompilerGLSL::builtin_to_glsl(builtin, storage);
break;
default:
break;
}
return CompilerGLSL::builtin_to_glsl(builtin, storage);
}
// Returns an MSL string attribute qualifer for a SPIR-V builtin
string CompilerMSL::builtin_qualifier(BuiltIn builtin)
{
auto &execution = get_entry_point();
switch (builtin)
{
// Vertex function in
case BuiltInVertexId:
return "vertex_id";
case BuiltInVertexIndex:
return "vertex_id";
case BuiltInBaseVertex:
return "base_vertex";
case BuiltInInstanceId:
return "instance_id";
case BuiltInInstanceIndex:
return "instance_id";
case BuiltInBaseInstance:
return "base_instance";
case BuiltInDrawIndex:
SPIRV_CROSS_THROW("DrawIndex is not supported in MSL.");
// Vertex function out
case BuiltInClipDistance:
return "clip_distance";
case BuiltInPointSize:
return "point_size";
case BuiltInPosition:
return "position";
case BuiltInLayer:
return "render_target_array_index";
// Fragment function in
case BuiltInFrontFacing:
return "front_facing";
case BuiltInPointCoord:
return "point_coord";
case BuiltInFragCoord:
return "position";
case BuiltInSampleId:
return "sample_id";
case BuiltInSampleMask:
return "sample_mask";
// Fragment function out
case BuiltInFragDepth:
if (execution.flags.get(ExecutionModeDepthGreater))
return "depth(greater)";
else if (execution.flags.get(ExecutionModeDepthLess))
return "depth(less)";
else
return "depth(any)";
// Compute function in
case BuiltInGlobalInvocationId:
return "thread_position_in_grid";
case BuiltInWorkgroupId:
return "threadgroup_position_in_grid";
case BuiltInNumWorkgroups:
return "threadgroups_per_grid";
case BuiltInLocalInvocationId:
return "thread_position_in_threadgroup";
case BuiltInLocalInvocationIndex:
return "thread_index_in_threadgroup";
default:
return "unsupported-built-in";
}
}
// Returns an MSL string type declaration for a SPIR-V builtin
string CompilerMSL::builtin_type_decl(BuiltIn builtin)
{
switch (builtin)
{
// Vertex function in
case BuiltInVertexId:
return "uint";
case BuiltInVertexIndex:
return "uint";
case BuiltInBaseVertex:
return "uint";
case BuiltInInstanceId:
return "uint";
case BuiltInInstanceIndex:
return "uint";
case BuiltInBaseInstance:
return "uint";
case BuiltInDrawIndex:
SPIRV_CROSS_THROW("DrawIndex is not supported in MSL.");
// Vertex function out
case BuiltInClipDistance:
return "float";
case BuiltInPointSize:
return "float";
case BuiltInPosition:
return "float4";
case BuiltInLayer:
return "uint";
// Fragment function in
case BuiltInFrontFacing:
return "bool";
case BuiltInPointCoord:
return "float2";
case BuiltInFragCoord:
return "float4";
case BuiltInSampleId:
return "uint";
case BuiltInSampleMask:
return "uint";
// Fragment function out
case BuiltInFragDepth:
return "float";
// Compute function in
case BuiltInGlobalInvocationId:
case BuiltInLocalInvocationId:
case BuiltInNumWorkgroups:
case BuiltInWorkgroupId:
return "uint3";
case BuiltInLocalInvocationIndex:
return "uint";
default:
return "unsupported-built-in-type";
}
}
// Returns the declaration of a built-in argument to a function
string CompilerMSL::built_in_func_arg(BuiltIn builtin, bool prefix_comma)
{
string bi_arg;
if (prefix_comma)
bi_arg += ", ";
bi_arg += builtin_type_decl(builtin);
bi_arg += " " + builtin_to_glsl(builtin, StorageClassInput);
bi_arg += " [[" + builtin_qualifier(builtin) + "]]";
return bi_arg;
}
// Returns the byte size of a struct member.
size_t CompilerMSL::get_declared_struct_member_size(const SPIRType &struct_type, uint32_t index) const
{
auto &type = get<SPIRType>(struct_type.member_types[index]);
switch (type.basetype)
{
case SPIRType::Unknown:
case SPIRType::Void:
case SPIRType::AtomicCounter:
case SPIRType::Image:
case SPIRType::SampledImage:
case SPIRType::Sampler:
SPIRV_CROSS_THROW("Querying size of opaque object.");
default:
{
// For arrays, we can use ArrayStride to get an easy check.
// Runtime arrays will have zero size so force to min of one.
if (!type.array.empty())
{
bool array_size_literal = type.array_size_literal.back();
uint32_t array_size =
array_size_literal ? type.array.back() : get<SPIRConstant>(type.array.back()).scalar();
return type_struct_member_array_stride(struct_type, index) * max(array_size, 1u);
}
if (type.basetype == SPIRType::Struct)
return get_declared_struct_size(type);
uint32_t component_size = type.width / 8;
uint32_t vecsize = type.vecsize;
uint32_t columns = type.columns;
// An unpacked 3-element vector or matrix column is the same memory size as a 4-element.
if (vecsize == 3 && !has_member_decoration(struct_type.self, index, DecorationCPacked))
vecsize = 4;
return component_size * vecsize * columns;
}
}
}
// Returns the byte alignment of a struct member.
size_t CompilerMSL::get_declared_struct_member_alignment(const SPIRType &struct_type, uint32_t index) const
{
auto &type = get<SPIRType>(struct_type.member_types[index]);
switch (type.basetype)
{
case SPIRType::Unknown:
case SPIRType::Void:
case SPIRType::AtomicCounter:
case SPIRType::Image:
case SPIRType::SampledImage:
case SPIRType::Sampler:
SPIRV_CROSS_THROW("Querying alignment of opaque object.");
case SPIRType::Struct:
return 16; // Per Vulkan spec section 14.5.4
default:
{
// Alignment of packed type is the same as the underlying component or column size.
// Alignment of unpacked type is the same as the vector size.
// Alignment of 3-elements vector is the same as 4-elements (including packed using column).
if (member_is_packed_type(struct_type, index))
return (type.width / 8) * (type.columns == 3 ? 4 : type.columns);
else
return (type.width / 8) * (type.vecsize == 3 ? 4 : type.vecsize);
}
}
}
bool CompilerMSL::skip_argument(uint32_t) const
{
return false;
}
bool CompilerMSL::OpCodePreprocessor::handle(Op opcode, const uint32_t *args, uint32_t length)
{
// Since MSL exists in a single execution scope, function prototype declarations are not
// needed, and clutter the output. If secondary functions are output (either as a SPIR-V
// function implementation or as indicated by the presence of OpFunctionCall), then set
// suppress_missing_prototypes to suppress compiler warnings of missing function prototypes.
// Mark if the input requires the implementation of an SPIR-V function that does not exist in Metal.
SPVFuncImpl spv_func = get_spv_func_impl(opcode, args);
if (spv_func != SPVFuncImplNone)
{
compiler.spv_function_implementations.insert(spv_func);
suppress_missing_prototypes = true;
}
switch (opcode)
{
case OpFunctionCall:
suppress_missing_prototypes = true;
break;
case OpImageWrite:
uses_resource_write = true;
break;
case OpStore:
check_resource_write(args[0]);
break;
case OpAtomicExchange:
case OpAtomicCompareExchange:
case OpAtomicCompareExchangeWeak:
case OpAtomicIIncrement:
case OpAtomicIDecrement:
case OpAtomicIAdd:
case OpAtomicISub:
case OpAtomicSMin:
case OpAtomicUMin:
case OpAtomicSMax:
case OpAtomicUMax:
case OpAtomicAnd:
case OpAtomicOr:
case OpAtomicXor:
uses_atomics = true;
check_resource_write(args[2]);
break;
case OpAtomicLoad:
uses_atomics = true;
break;
default:
break;
}
// If it has one, keep track of the instruction's result type, mapped by ID
uint32_t result_type, result_id;
if (compiler.instruction_to_result_type(result_type, result_id, opcode, args, length))
result_types[result_id] = result_type;
return true;
}
// If the variable is a Uniform or StorageBuffer, mark that a resource has been written to.
void CompilerMSL::OpCodePreprocessor::check_resource_write(uint32_t var_id)
{
auto *p_var = compiler.maybe_get_backing_variable(var_id);
StorageClass sc = p_var ? p_var->storage : StorageClassMax;
if (sc == StorageClassUniform || sc == StorageClassStorageBuffer)
uses_resource_write = true;
}
// Returns an enumeration of a SPIR-V function that needs to be output for certain Op codes.
CompilerMSL::SPVFuncImpl CompilerMSL::OpCodePreprocessor::get_spv_func_impl(Op opcode, const uint32_t *args)
{
switch (opcode)
{
case OpFMod:
return SPVFuncImplMod;
case OpFunctionCall:
{
auto &return_type = compiler.get<SPIRType>(args[0]);
if (!return_type.array.empty())
return SPVFuncImplArrayCopy;
break;
}
case OpStore:
{
// Get the result type of the RHS. Since this is run as a pre-processing stage,
// we must extract the result type directly from the Instruction, rather than the ID.
uint32_t id_lhs = args[0];
uint32_t id_rhs = args[1];
const SPIRType *type = nullptr;
if (compiler.ids[id_rhs].get_type() != TypeNone)
{
// Could be a constant, or similar.
type = &compiler.expression_type(id_rhs);
}
else
{
// Or ... an expression.
uint32_t tid = result_types[id_rhs];
if (tid)
type = &compiler.get<SPIRType>(tid);
}
auto *var = compiler.maybe_get<SPIRVariable>(id_lhs);
// Are we simply assigning to a statically assigned variable which takes a constant?
// Don't bother emitting this function.
bool static_expression_lhs =
var && var->storage == StorageClassFunction && var->statically_assigned && var->remapped_variable;
if (type && compiler.is_array(*type) && !static_expression_lhs)
return SPVFuncImplArrayCopy;
break;
}
case OpImageFetch:
case OpImageWrite:
{
// Retrieve the image type, and if it's a Buffer, emit a texel coordinate function
uint32_t tid = result_types[args[opcode == OpImageWrite ? 0 : 2]];
if (tid && compiler.get<SPIRType>(tid).image.dim == DimBuffer)
return SPVFuncImplTexelBufferCoords;
break;
}
case OpExtInst:
{
uint32_t extension_set = args[2];
if (compiler.get<SPIRExtension>(extension_set).ext == SPIRExtension::GLSL)
{
GLSLstd450 op_450 = static_cast<GLSLstd450>(args[3]);
switch (op_450)
{
case GLSLstd450Radians:
return SPVFuncImplRadians;
case GLSLstd450Degrees:
return SPVFuncImplDegrees;
case GLSLstd450FindILsb:
return SPVFuncImplFindILsb;
case GLSLstd450FindSMsb:
return SPVFuncImplFindSMsb;
case GLSLstd450FindUMsb:
return SPVFuncImplFindUMsb;
case GLSLstd450MatrixInverse:
{
auto &mat_type = compiler.get<SPIRType>(args[0]);
switch (mat_type.columns)
{
case 2:
return SPVFuncImplInverse2x2;
case 3:
return SPVFuncImplInverse3x3;
case 4:
return SPVFuncImplInverse4x4;
default:
break;
}
break;
}
default:
break;
}
}
break;
}
default:
break;
}
return SPVFuncImplNone;
}
// Sort both type and meta member content based on builtin status (put builtins at end),
// then by the required sorting aspect.
void CompilerMSL::MemberSorter::sort()
{
// Create a temporary array of consecutive member indices and sort it based on how
// the members should be reordered, based on builtin and sorting aspect meta info.
size_t mbr_cnt = type.member_types.size();
vector<uint32_t> mbr_idxs(mbr_cnt);
iota(mbr_idxs.begin(), mbr_idxs.end(), 0); // Fill with consecutive indices
std::sort(mbr_idxs.begin(), mbr_idxs.end(), *this); // Sort member indices based on sorting aspect
// Move type and meta member info to the order defined by the sorted member indices.
// This is done by creating temporary copies of both member types and meta, and then
// copying back to the original content at the sorted indices.
auto mbr_types_cpy = type.member_types;
auto mbr_meta_cpy = meta.members;
for (uint32_t mbr_idx = 0; mbr_idx < mbr_cnt; mbr_idx++)
{
type.member_types[mbr_idx] = mbr_types_cpy[mbr_idxs[mbr_idx]];
meta.members[mbr_idx] = mbr_meta_cpy[mbr_idxs[mbr_idx]];
}
}
// Sort first by builtin status (put builtins at end), then by the sorting aspect.
bool CompilerMSL::MemberSorter::operator()(uint32_t mbr_idx1, uint32_t mbr_idx2)
{
auto &mbr_meta1 = meta.members[mbr_idx1];
auto &mbr_meta2 = meta.members[mbr_idx2];
if (mbr_meta1.builtin != mbr_meta2.builtin)
return mbr_meta2.builtin;
else
switch (sort_aspect)
{
case Location:
return mbr_meta1.location < mbr_meta2.location;
case LocationReverse:
return mbr_meta1.location > mbr_meta2.location;
case Offset:
return mbr_meta1.offset < mbr_meta2.offset;
case OffsetThenLocationReverse:
return (mbr_meta1.offset < mbr_meta2.offset) ||
((mbr_meta1.offset == mbr_meta2.offset) && (mbr_meta1.location > mbr_meta2.location));
case Alphabetical:
return mbr_meta1.alias < mbr_meta2.alias;
default:
return false;
}
}
CompilerMSL::MemberSorter::MemberSorter(SPIRType &t, Meta &m, SortAspect sa)
: type(t)
, meta(m)
, sort_aspect(sa)
{
// Ensure enough meta info is available
meta.members.resize(max(type.member_types.size(), meta.members.size()));
}
void CompilerMSL::remap_constexpr_sampler(uint32_t id, const MSLConstexprSampler &sampler)
{
auto &type = get<SPIRType>(get<SPIRVariable>(id).basetype);
if (type.basetype != SPIRType::SampledImage && type.basetype != SPIRType::Sampler)
SPIRV_CROSS_THROW("Can only remap SampledImage and Sampler type.");
if (!type.array.empty())
SPIRV_CROSS_THROW("Can not remap array of samplers.");
constexpr_samplers[id] = sampler;
}
void CompilerMSL::bitcast_from_builtin_load(uint32_t source_id, std::string &expr, const SPIRType &expr_type)
{
auto *var = maybe_get_backing_variable(source_id);
if (var)
source_id = var->self;
// Only interested in standalone builtin variables.
if (!has_decoration(source_id, DecorationBuiltIn))
return;
auto builtin = static_cast<BuiltIn>(get_decoration(source_id, DecorationBuiltIn));
auto expected_type = expr_type.basetype;
switch (builtin)
{
case BuiltInGlobalInvocationId:
case BuiltInLocalInvocationId:
case BuiltInWorkgroupId:
case BuiltInLocalInvocationIndex:
case BuiltInWorkgroupSize:
case BuiltInNumWorkgroups:
expected_type = SPIRType::UInt;
break;
default:
break;
}
if (expected_type != expr_type.basetype)
expr = bitcast_expression(expr_type, expected_type, expr);
}
// MSL always declares output builtins with the SPIR-V type.
void CompilerMSL::bitcast_to_builtin_store(uint32_t, std::string &, const SPIRType &)
{
}
std::string CompilerMSL::to_initializer_expression(const SPIRVariable &var)
{
// We risk getting an array initializer here with MSL. If we have an array.
// FIXME: We cannot handle non-constant arrays being initialized.
// We will need to inject spvArrayCopy here somehow ...
auto &type = get<SPIRType>(var.basetype);
if (ids[var.initializer].get_type() == TypeConstant && (!type.array.empty() || type.basetype == SPIRType::Struct))
return constant_expression(get<SPIRConstant>(var.initializer));
else
return CompilerGLSL::to_initializer_expression(var);
}