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fuchsia / third_party / spirv-cross / refs/tags/2019-07-26 / . / spirv_cross.cpp
blob: 3a9670ed49c4127de7c94f2aef1bcbc7cade7d74 [file] [log] [blame]
/*
* Copyright 2015-2019 Arm Limited
*
* 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_cross.hpp"
#include "GLSL.std.450.h"
#include "spirv_cfg.hpp"
#include "spirv_common.hpp"
#include "spirv_parser.hpp"
#include <algorithm>
#include <cstring>
#include <utility>
using namespace std;
using namespace spv;
using namespace SPIRV_CROSS_NAMESPACE;
Compiler::Compiler(vector<uint32_t> ir_)
{
Parser parser(move(ir_));
parser.parse();
set_ir(move(parser.get_parsed_ir()));
}
Compiler::Compiler(const uint32_t *ir_, size_t word_count)
{
Parser parser(ir_, word_count);
parser.parse();
set_ir(move(parser.get_parsed_ir()));
}
Compiler::Compiler(const ParsedIR &ir_)
{
set_ir(ir_);
}
Compiler::Compiler(ParsedIR &&ir_)
{
set_ir(move(ir_));
}
void Compiler::set_ir(ParsedIR &&ir_)
{
ir = move(ir_);
parse_fixup();
}
void Compiler::set_ir(const ParsedIR &ir_)
{
ir = ir_;
parse_fixup();
}
string Compiler::compile()
{
return "";
}
bool Compiler::variable_storage_is_aliased(const SPIRVariable &v)
{
auto &type = get<SPIRType>(v.basetype);
bool ssbo = v.storage == StorageClassStorageBuffer ||
ir.meta[type.self].decoration.decoration_flags.get(DecorationBufferBlock);
bool image = type.basetype == SPIRType::Image;
bool counter = type.basetype == SPIRType::AtomicCounter;
bool buffer_reference = type.storage == StorageClassPhysicalStorageBufferEXT;
bool is_restrict;
if (ssbo)
is_restrict = ir.get_buffer_block_flags(v).get(DecorationRestrict);
else
is_restrict = has_decoration(v.self, DecorationRestrict);
return !is_restrict && (ssbo || image || counter || buffer_reference);
}
bool Compiler::block_is_pure(const SPIRBlock &block)
{
for (auto &i : block.ops)
{
auto ops = stream(i);
auto op = static_cast<Op>(i.op);
switch (op)
{
case OpFunctionCall:
{
uint32_t func = ops[2];
if (!function_is_pure(get<SPIRFunction>(func)))
return false;
break;
}
case OpCopyMemory:
case OpStore:
{
auto &type = expression_type(ops[0]);
if (type.storage != StorageClassFunction)
return false;
break;
}
case OpImageWrite:
return false;
// Atomics are impure.
case OpAtomicLoad:
case OpAtomicStore:
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:
return false;
// Geometry shader builtins modify global state.
case OpEndPrimitive:
case OpEmitStreamVertex:
case OpEndStreamPrimitive:
case OpEmitVertex:
return false;
// Barriers disallow any reordering, so we should treat blocks with barrier as writing.
case OpControlBarrier:
case OpMemoryBarrier:
return false;
// Ray tracing builtins are impure.
case OpReportIntersectionNV:
case OpIgnoreIntersectionNV:
case OpTerminateRayNV:
case OpTraceNV:
case OpExecuteCallableNV:
return false;
// OpExtInst is potentially impure depending on extension, but GLSL builtins are at least pure.
default:
break;
}
}
return true;
}
string Compiler::to_name(uint32_t id, bool allow_alias) const
{
if (allow_alias && ir.ids[id].get_type() == TypeType)
{
// If this type is a simple alias, emit the
// name of the original type instead.
// We don't want to override the meta alias
// as that can be overridden by the reflection APIs after parse.
auto &type = get<SPIRType>(id);
if (type.type_alias)
{
// If the alias master has been specially packed, we will have emitted a clean variant as well,
// so skip the name aliasing here.
if (!has_extended_decoration(type.type_alias, SPIRVCrossDecorationBufferBlockRepacked))
return to_name(type.type_alias);
}
}
auto &alias = ir.get_name(id);
if (alias.empty())
return join("_", id);
else
return alias;
}
bool Compiler::function_is_pure(const SPIRFunction &func)
{
for (auto block : func.blocks)
{
if (!block_is_pure(get<SPIRBlock>(block)))
{
//fprintf(stderr, "Function %s is impure!\n", to_name(func.self).c_str());
return false;
}
}
//fprintf(stderr, "Function %s is pure!\n", to_name(func.self).c_str());
return true;
}
void Compiler::register_global_read_dependencies(const SPIRBlock &block, uint32_t id)
{
for (auto &i : block.ops)
{
auto ops = stream(i);
auto op = static_cast<Op>(i.op);
switch (op)
{
case OpFunctionCall:
{
uint32_t func = ops[2];
register_global_read_dependencies(get<SPIRFunction>(func), id);
break;
}
case OpLoad:
case OpImageRead:
{
// If we're in a storage class which does not get invalidated, adding dependencies here is no big deal.
auto *var = maybe_get_backing_variable(ops[2]);
if (var && var->storage != StorageClassFunction)
{
auto &type = get<SPIRType>(var->basetype);
// InputTargets are immutable.
if (type.basetype != SPIRType::Image && type.image.dim != DimSubpassData)
var->dependees.push_back(id);
}
break;
}
default:
break;
}
}
}
void Compiler::register_global_read_dependencies(const SPIRFunction &func, uint32_t id)
{
for (auto block : func.blocks)
register_global_read_dependencies(get<SPIRBlock>(block), id);
}
SPIRVariable *Compiler::maybe_get_backing_variable(uint32_t chain)
{
auto *var = maybe_get<SPIRVariable>(chain);
if (!var)
{
auto *cexpr = maybe_get<SPIRExpression>(chain);
if (cexpr)
var = maybe_get<SPIRVariable>(cexpr->loaded_from);
auto *access_chain = maybe_get<SPIRAccessChain>(chain);
if (access_chain)
var = maybe_get<SPIRVariable>(access_chain->loaded_from);
}
return var;
}
void Compiler::register_read(uint32_t expr, uint32_t chain, bool forwarded)
{
auto &e = get<SPIRExpression>(expr);
auto *var = maybe_get_backing_variable(chain);
if (var)
{
e.loaded_from = var->self;
// If the backing variable is immutable, we do not need to depend on the variable.
if (forwarded && !is_immutable(var->self))
var->dependees.push_back(e.self);
// If we load from a parameter, make sure we create "inout" if we also write to the parameter.
// The default is "in" however, so we never invalidate our compilation by reading.
if (var && var->parameter)
var->parameter->read_count++;
}
}
void Compiler::register_write(uint32_t chain)
{
auto *var = maybe_get<SPIRVariable>(chain);
if (!var)
{
// If we're storing through an access chain, invalidate the backing variable instead.
auto *expr = maybe_get<SPIRExpression>(chain);
if (expr && expr->loaded_from)
var = maybe_get<SPIRVariable>(expr->loaded_from);
auto *access_chain = maybe_get<SPIRAccessChain>(chain);
if (access_chain && access_chain->loaded_from)
var = maybe_get<SPIRVariable>(access_chain->loaded_from);
}
if (var)
{
bool check_argument_storage_qualifier = true;
auto &type = expression_type(chain);
// If our variable is in a storage class which can alias with other buffers,
// invalidate all variables which depend on aliased variables. And if this is a
// variable pointer, then invalidate all variables regardless.
if (get_variable_data_type(*var).pointer)
{
flush_all_active_variables();
if (type.pointer_depth == 1)
{
// We have a backing variable which is a pointer-to-pointer type.
// We are storing some data through a pointer acquired through that variable,
// but we are not writing to the value of the variable itself,
// i.e., we are not modifying the pointer directly.
// If we are storing a non-pointer type (pointer_depth == 1),
// we know that we are storing some unrelated data.
// A case here would be
// void foo(Foo * const *arg) {
// Foo *bar = *arg;
// bar->unrelated = 42;
// }
// arg, the argument is constant.
check_argument_storage_qualifier = false;
}
}
if (type.storage == StorageClassPhysicalStorageBufferEXT || variable_storage_is_aliased(*var))
flush_all_aliased_variables();
else if (var)
flush_dependees(*var);
// We tried to write to a parameter which is not marked with out qualifier, force a recompile.
if (check_argument_storage_qualifier && var->parameter && var->parameter->write_count == 0)
{
var->parameter->write_count++;
force_recompile();
}
}
else
{
// If we stored through a variable pointer, then we don't know which
// variable we stored to. So *all* expressions after this point need to
// be invalidated.
// FIXME: If we can prove that the variable pointer will point to
// only certain variables, we can invalidate only those.
flush_all_active_variables();
}
}
void Compiler::flush_dependees(SPIRVariable &var)
{
for (auto expr : var.dependees)
invalid_expressions.insert(expr);
var.dependees.clear();
}
void Compiler::flush_all_aliased_variables()
{
for (auto aliased : aliased_variables)
flush_dependees(get<SPIRVariable>(aliased));
}
void Compiler::flush_all_atomic_capable_variables()
{
for (auto global : global_variables)
flush_dependees(get<SPIRVariable>(global));
flush_all_aliased_variables();
}
void Compiler::flush_control_dependent_expressions(uint32_t block_id)
{
auto &block = get<SPIRBlock>(block_id);
for (auto &expr : block.invalidate_expressions)
invalid_expressions.insert(expr);
block.invalidate_expressions.clear();
}
void Compiler::flush_all_active_variables()
{
// Invalidate all temporaries we read from variables in this block since they were forwarded.
// Invalidate all temporaries we read from globals.
for (auto &v : current_function->local_variables)
flush_dependees(get<SPIRVariable>(v));
for (auto &arg : current_function->arguments)
flush_dependees(get<SPIRVariable>(arg.id));
for (auto global : global_variables)
flush_dependees(get<SPIRVariable>(global));
flush_all_aliased_variables();
}
uint32_t Compiler::expression_type_id(uint32_t id) const
{
switch (ir.ids[id].get_type())
{
case TypeVariable:
return get<SPIRVariable>(id).basetype;
case TypeExpression:
return get<SPIRExpression>(id).expression_type;
case TypeConstant:
return get<SPIRConstant>(id).constant_type;
case TypeConstantOp:
return get<SPIRConstantOp>(id).basetype;
case TypeUndef:
return get<SPIRUndef>(id).basetype;
case TypeCombinedImageSampler:
return get<SPIRCombinedImageSampler>(id).combined_type;
case TypeAccessChain:
return get<SPIRAccessChain>(id).basetype;
default:
SPIRV_CROSS_THROW("Cannot resolve expression type.");
}
}
const SPIRType &Compiler::expression_type(uint32_t id) const
{
return get<SPIRType>(expression_type_id(id));
}
bool Compiler::expression_is_lvalue(uint32_t id) const
{
auto &type = expression_type(id);
switch (type.basetype)
{
case SPIRType::SampledImage:
case SPIRType::Image:
case SPIRType::Sampler:
return false;
default:
return true;
}
}
bool Compiler::is_immutable(uint32_t id) const
{
if (ir.ids[id].get_type() == TypeVariable)
{
auto &var = get<SPIRVariable>(id);
// Anything we load from the UniformConstant address space is guaranteed to be immutable.
bool pointer_to_const = var.storage == StorageClassUniformConstant;
return pointer_to_const || var.phi_variable || !expression_is_lvalue(id);
}
else if (ir.ids[id].get_type() == TypeAccessChain)
return get<SPIRAccessChain>(id).immutable;
else if (ir.ids[id].get_type() == TypeExpression)
return get<SPIRExpression>(id).immutable;
else if (ir.ids[id].get_type() == TypeConstant || ir.ids[id].get_type() == TypeConstantOp ||
ir.ids[id].get_type() == TypeUndef)
return true;
else
return false;
}
static inline bool storage_class_is_interface(spv::StorageClass storage)
{
switch (storage)
{
case StorageClassInput:
case StorageClassOutput:
case StorageClassUniform:
case StorageClassUniformConstant:
case StorageClassAtomicCounter:
case StorageClassPushConstant:
case StorageClassStorageBuffer:
return true;
default:
return false;
}
}
bool Compiler::is_hidden_variable(const SPIRVariable &var, bool include_builtins) const
{
if ((is_builtin_variable(var) && !include_builtins) || var.remapped_variable)
return true;
// Combined image samplers are always considered active as they are "magic" variables.
if (find_if(begin(combined_image_samplers), end(combined_image_samplers), [&var](const CombinedImageSampler &samp) {
return samp.combined_id == var.self;
}) != end(combined_image_samplers))
{
return false;
}
bool hidden = false;
if (check_active_interface_variables && storage_class_is_interface(var.storage))
hidden = active_interface_variables.find(var.self) == end(active_interface_variables);
return hidden;
}
bool Compiler::is_builtin_type(const SPIRType &type) const
{
auto *type_meta = ir.find_meta(type.self);
// We can have builtin structs as well. If one member of a struct is builtin, the struct must also be builtin.
if (type_meta)
for (auto &m : type_meta->members)
if (m.builtin)
return true;
return false;
}
bool Compiler::is_builtin_variable(const SPIRVariable &var) const
{
auto *m = ir.find_meta(var.self);
if (var.compat_builtin || (m && m->decoration.builtin))
return true;
else
return is_builtin_type(get<SPIRType>(var.basetype));
}
bool Compiler::is_member_builtin(const SPIRType &type, uint32_t index, BuiltIn *builtin) const
{
auto *type_meta = ir.find_meta(type.self);
if (type_meta)
{
auto &memb = type_meta->members;
if (index < memb.size() && memb[index].builtin)
{
if (builtin)
*builtin = memb[index].builtin_type;
return true;
}
}
return false;
}
bool Compiler::is_scalar(const SPIRType &type) const
{
return type.basetype != SPIRType::Struct && type.vecsize == 1 && type.columns == 1;
}
bool Compiler::is_vector(const SPIRType &type) const
{
return type.vecsize > 1 && type.columns == 1;
}
bool Compiler::is_matrix(const SPIRType &type) const
{
return type.vecsize > 1 && type.columns > 1;
}
bool Compiler::is_array(const SPIRType &type) const
{
return !type.array.empty();
}
ShaderResources Compiler::get_shader_resources() const
{
return get_shader_resources(nullptr);
}
ShaderResources Compiler::get_shader_resources(const unordered_set<uint32_t> &active_variables) const
{
return get_shader_resources(&active_variables);
}
bool Compiler::InterfaceVariableAccessHandler::handle(Op opcode, const uint32_t *args, uint32_t length)
{
uint32_t variable = 0;
switch (opcode)
{
// Need this first, otherwise, GCC complains about unhandled switch statements.
default:
break;
case OpFunctionCall:
{
// Invalid SPIR-V.
if (length < 3)
return false;
uint32_t count = length - 3;
args += 3;
for (uint32_t i = 0; i < count; i++)
{
auto *var = compiler.maybe_get<SPIRVariable>(args[i]);
if (var && storage_class_is_interface(var->storage))
variables.insert(args[i]);
}
break;
}
case OpSelect:
{
// Invalid SPIR-V.
if (length < 5)
return false;
uint32_t count = length - 3;
args += 3;
for (uint32_t i = 0; i < count; i++)
{
auto *var = compiler.maybe_get<SPIRVariable>(args[i]);
if (var && storage_class_is_interface(var->storage))
variables.insert(args[i]);
}
break;
}
case OpPhi:
{
// Invalid SPIR-V.
if (length < 2)
return false;
uint32_t count = length - 2;
args += 2;
for (uint32_t i = 0; i < count; i += 2)
{
auto *var = compiler.maybe_get<SPIRVariable>(args[i]);
if (var && storage_class_is_interface(var->storage))
variables.insert(args[i]);
}
break;
}
case OpAtomicStore:
case OpStore:
// Invalid SPIR-V.
if (length < 1)
return false;
variable = args[0];
break;
case OpCopyMemory:
{
if (length < 2)
return false;
auto *var = compiler.maybe_get<SPIRVariable>(args[0]);
if (var && storage_class_is_interface(var->storage))
variables.insert(args[0]);
var = compiler.maybe_get<SPIRVariable>(args[1]);
if (var && storage_class_is_interface(var->storage))
variables.insert(args[1]);
break;
}
case OpExtInst:
{
if (length < 5)
return false;
uint32_t extension_set = args[2];
if (compiler.get<SPIRExtension>(extension_set).ext == SPIRExtension::SPV_AMD_shader_explicit_vertex_parameter)
{
enum AMDShaderExplicitVertexParameter
{
InterpolateAtVertexAMD = 1
};
auto op = static_cast<AMDShaderExplicitVertexParameter>(args[3]);
switch (op)
{
case InterpolateAtVertexAMD:
{
auto *var = compiler.maybe_get<SPIRVariable>(args[4]);
if (var && storage_class_is_interface(var->storage))
variables.insert(args[4]);
break;
}
default:
break;
}
}
break;
}
case OpAccessChain:
case OpInBoundsAccessChain:
case OpPtrAccessChain:
case OpLoad:
case OpCopyObject:
case OpImageTexelPointer:
case OpAtomicLoad:
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:
case OpArrayLength:
// Invalid SPIR-V.
if (length < 3)
return false;
variable = args[2];
break;
}
if (variable)
{
auto *var = compiler.maybe_get<SPIRVariable>(variable);
if (var && storage_class_is_interface(var->storage))
variables.insert(variable);
}
return true;
}
unordered_set<uint32_t> Compiler::get_active_interface_variables() const
{
// Traverse the call graph and find all interface variables which are in use.
unordered_set<uint32_t> variables;
InterfaceVariableAccessHandler handler(*this, variables);
traverse_all_reachable_opcodes(get<SPIRFunction>(ir.default_entry_point), handler);
// Make sure we preserve output variables which are only initialized, but never accessed by any code.
ir.for_each_typed_id<SPIRVariable>([&](uint32_t, const SPIRVariable &var) {
if (var.storage == StorageClassOutput && var.initializer != 0)
variables.insert(var.self);
});
// If we needed to create one, we'll need it.
if (dummy_sampler_id)
variables.insert(dummy_sampler_id);
return variables;
}
void Compiler::set_enabled_interface_variables(std::unordered_set<uint32_t> active_variables)
{
active_interface_variables = move(active_variables);
check_active_interface_variables = true;
}
ShaderResources Compiler::get_shader_resources(const unordered_set<uint32_t> *active_variables) const
{
ShaderResources res;
bool ssbo_instance_name = reflection_ssbo_instance_name_is_significant();
ir.for_each_typed_id<SPIRVariable>([&](uint32_t, const SPIRVariable &var) {
auto &type = this->get<SPIRType>(var.basetype);
// It is possible for uniform storage classes to be passed as function parameters, so detect
// that. To detect function parameters, check of StorageClass of variable is function scope.
if (var.storage == StorageClassFunction || !type.pointer || is_builtin_variable(var))
return;
if (active_variables && active_variables->find(var.self) == end(*active_variables))
return;
// Input
if (var.storage == StorageClassInput && interface_variable_exists_in_entry_point(var.self))
{
if (has_decoration(type.self, DecorationBlock))
{
res.stage_inputs.push_back(
{ var.self, var.basetype, type.self, get_remapped_declared_block_name(var.self, false) });
}
else
res.stage_inputs.push_back({ var.self, var.basetype, type.self, get_name(var.self) });
}
// Subpass inputs
else if (var.storage == StorageClassUniformConstant && type.image.dim == DimSubpassData)
{
res.subpass_inputs.push_back({ var.self, var.basetype, type.self, get_name(var.self) });
}
// Outputs
else if (var.storage == StorageClassOutput && interface_variable_exists_in_entry_point(var.self))
{
if (has_decoration(type.self, DecorationBlock))
{
res.stage_outputs.push_back(
{ var.self, var.basetype, type.self, get_remapped_declared_block_name(var.self, false) });
}
else
res.stage_outputs.push_back({ var.self, var.basetype, type.self, get_name(var.self) });
}
// UBOs
else if (type.storage == StorageClassUniform && has_decoration(type.self, DecorationBlock))
{
res.uniform_buffers.push_back(
{ var.self, var.basetype, type.self, get_remapped_declared_block_name(var.self, false) });
}
// Old way to declare SSBOs.
else if (type.storage == StorageClassUniform && has_decoration(type.self, DecorationBufferBlock))
{
res.storage_buffers.push_back(
{ var.self, var.basetype, type.self, get_remapped_declared_block_name(var.self, ssbo_instance_name) });
}
// Modern way to declare SSBOs.
else if (type.storage == StorageClassStorageBuffer)
{
res.storage_buffers.push_back(
{ var.self, var.basetype, type.self, get_remapped_declared_block_name(var.self, ssbo_instance_name) });
}
// Push constant blocks
else if (type.storage == StorageClassPushConstant)
{
// There can only be one push constant block, but keep the vector in case this restriction is lifted
// in the future.
res.push_constant_buffers.push_back({ var.self, var.basetype, type.self, get_name(var.self) });
}
// Images
else if (type.storage == StorageClassUniformConstant && type.basetype == SPIRType::Image &&
type.image.sampled == 2)
{
res.storage_images.push_back({ var.self, var.basetype, type.self, get_name(var.self) });
}
// Separate images
else if (type.storage == StorageClassUniformConstant && type.basetype == SPIRType::Image &&
type.image.sampled == 1)
{
res.separate_images.push_back({ var.self, var.basetype, type.self, get_name(var.self) });
}
// Separate samplers
else if (type.storage == StorageClassUniformConstant && type.basetype == SPIRType::Sampler)
{
res.separate_samplers.push_back({ var.self, var.basetype, type.self, get_name(var.self) });
}
// Textures
else if (type.storage == StorageClassUniformConstant && type.basetype == SPIRType::SampledImage)
{
res.sampled_images.push_back({ var.self, var.basetype, type.self, get_name(var.self) });
}
// Atomic counters
else if (type.storage == StorageClassAtomicCounter)
{
res.atomic_counters.push_back({ var.self, var.basetype, type.self, get_name(var.self) });
}
// Acceleration structures
else if (type.storage == StorageClassUniformConstant && type.basetype == SPIRType::AccelerationStructureNV)
{
res.acceleration_structures.push_back({ var.self, var.basetype, type.self, get_name(var.self) });
}
});
return res;
}
bool Compiler::type_is_block_like(const SPIRType &type) const
{
if (type.basetype != SPIRType::Struct)
return false;
if (has_decoration(type.self, DecorationBlock) || has_decoration(type.self, DecorationBufferBlock))
{
return true;
}
// Block-like types may have Offset decorations.
for (uint32_t i = 0; i < uint32_t(type.member_types.size()); i++)
if (has_member_decoration(type.self, i, DecorationOffset))
return true;
return false;
}
void Compiler::parse_fixup()
{
// Figure out specialization constants for work group sizes.
for (auto id_ : ir.ids_for_constant_or_variable)
{
auto &id = ir.ids[id_];
if (id.get_type() == TypeConstant)
{
auto &c = id.get<SPIRConstant>();
if (ir.meta[c.self].decoration.builtin && ir.meta[c.self].decoration.builtin_type == BuiltInWorkgroupSize)
{
// In current SPIR-V, there can be just one constant like this.
// All entry points will receive the constant value.
for (auto &entry : ir.entry_points)
{
entry.second.workgroup_size.constant = c.self;
entry.second.workgroup_size.x = c.scalar(0, 0);
entry.second.workgroup_size.y = c.scalar(0, 1);
entry.second.workgroup_size.z = c.scalar(0, 2);
}
}
}
else if (id.get_type() == TypeVariable)
{
auto &var = id.get<SPIRVariable>();
if (var.storage == StorageClassPrivate || var.storage == StorageClassWorkgroup ||
var.storage == StorageClassOutput)
global_variables.push_back(var.self);
if (variable_storage_is_aliased(var))
aliased_variables.push_back(var.self);
}
}
}
void Compiler::update_name_cache(unordered_set<string> &cache_primary, const unordered_set<string> &cache_secondary,
string &name)
{
if (name.empty())
return;
const auto find_name = [&](const string &n) -> bool {
if (cache_primary.find(n) != end(cache_primary))
return true;
if (&cache_primary != &cache_secondary)
if (cache_secondary.find(n) != end(cache_secondary))
return true;
return false;
};
const auto insert_name = [&](const string &n) { cache_primary.insert(n); };
if (!find_name(name))
{
insert_name(name);
return;
}
uint32_t counter = 0;
auto tmpname = name;
bool use_linked_underscore = true;
if (tmpname == "_")
{
// We cannot just append numbers, as we will end up creating internally reserved names.
// Make it like _0_<counter> instead.
tmpname += "0";
}
else if (tmpname.back() == '_')
{
// The last_character is an underscore, so we don't need to link in underscore.
// This would violate double underscore rules.
use_linked_underscore = false;
}
// If there is a collision (very rare),
// keep tacking on extra identifier until it's unique.
do
{
counter++;
name = tmpname + (use_linked_underscore ? "_" : "") + convert_to_string(counter);
} while (find_name(name));
insert_name(name);
}
void Compiler::update_name_cache(unordered_set<string> &cache, string &name)
{
update_name_cache(cache, cache, name);
}
void Compiler::set_name(uint32_t id, const std::string &name)
{
ir.set_name(id, name);
}
const SPIRType &Compiler::get_type(uint32_t id) const
{
return get<SPIRType>(id);
}
const SPIRType &Compiler::get_type_from_variable(uint32_t id) const
{
return get<SPIRType>(get<SPIRVariable>(id).basetype);
}
uint32_t Compiler::get_pointee_type_id(uint32_t type_id) const
{
auto *p_type = &get<SPIRType>(type_id);
if (p_type->pointer)
{
assert(p_type->parent_type);
type_id = p_type->parent_type;
}
return type_id;
}
const SPIRType &Compiler::get_pointee_type(const SPIRType &type) const
{
auto *p_type = &type;
if (p_type->pointer)
{
assert(p_type->parent_type);
p_type = &get<SPIRType>(p_type->parent_type);
}
return *p_type;
}
const SPIRType &Compiler::get_pointee_type(uint32_t type_id) const
{
return get_pointee_type(get<SPIRType>(type_id));
}
uint32_t Compiler::get_variable_data_type_id(const SPIRVariable &var) const
{
if (var.phi_variable)
return var.basetype;
return get_pointee_type_id(var.basetype);
}
SPIRType &Compiler::get_variable_data_type(const SPIRVariable &var)
{
return get<SPIRType>(get_variable_data_type_id(var));
}
const SPIRType &Compiler::get_variable_data_type(const SPIRVariable &var) const
{
return get<SPIRType>(get_variable_data_type_id(var));
}
SPIRType &Compiler::get_variable_element_type(const SPIRVariable &var)
{
SPIRType *type = &get_variable_data_type(var);
if (is_array(*type))
type = &get<SPIRType>(type->parent_type);
return *type;
}
const SPIRType &Compiler::get_variable_element_type(const SPIRVariable &var) const
{
const SPIRType *type = &get_variable_data_type(var);
if (is_array(*type))
type = &get<SPIRType>(type->parent_type);
return *type;
}
bool Compiler::is_sampled_image_type(const SPIRType &type)
{
return (type.basetype == SPIRType::Image || type.basetype == SPIRType::SampledImage) && type.image.sampled == 1 &&
type.image.dim != DimBuffer;
}
void Compiler::set_member_decoration_string(uint32_t id, uint32_t index, spv::Decoration decoration,
const std::string &argument)
{
ir.set_member_decoration_string(id, index, decoration, argument);
}
void Compiler::set_member_decoration(uint32_t id, uint32_t index, Decoration decoration, uint32_t argument)
{
ir.set_member_decoration(id, index, decoration, argument);
}
void Compiler::set_member_name(uint32_t id, uint32_t index, const std::string &name)
{
ir.set_member_name(id, index, name);
}
const std::string &Compiler::get_member_name(uint32_t id, uint32_t index) const
{
return ir.get_member_name(id, index);
}
void Compiler::set_qualified_name(uint32_t id, const string &name)
{
ir.meta[id].decoration.qualified_alias = name;
}
void Compiler::set_member_qualified_name(uint32_t type_id, uint32_t index, const std::string &name)
{
ir.meta[type_id].members.resize(max(ir.meta[type_id].members.size(), size_t(index) + 1));
ir.meta[type_id].members[index].qualified_alias = name;
}
const string &Compiler::get_member_qualified_name(uint32_t type_id, uint32_t index) const
{
auto *m = ir.find_meta(type_id);
if (m && index < m->members.size())
return m->members[index].qualified_alias;
else
return ir.get_empty_string();
}
uint32_t Compiler::get_member_decoration(uint32_t id, uint32_t index, Decoration decoration) const
{
return ir.get_member_decoration(id, index, decoration);
}
const Bitset &Compiler::get_member_decoration_bitset(uint32_t id, uint32_t index) const
{
return ir.get_member_decoration_bitset(id, index);
}
bool Compiler::has_member_decoration(uint32_t id, uint32_t index, Decoration decoration) const
{
return ir.has_member_decoration(id, index, decoration);
}
void Compiler::unset_member_decoration(uint32_t id, uint32_t index, Decoration decoration)
{
ir.unset_member_decoration(id, index, decoration);
}
void Compiler::set_decoration_string(uint32_t id, spv::Decoration decoration, const std::string &argument)
{
ir.set_decoration_string(id, decoration, argument);
}
void Compiler::set_decoration(uint32_t id, Decoration decoration, uint32_t argument)
{
ir.set_decoration(id, decoration, argument);
}
void Compiler::set_extended_decoration(uint32_t id, ExtendedDecorations decoration, uint32_t value)
{
auto &dec = ir.meta[id].decoration;
dec.extended.flags.set(decoration);
dec.extended.values[decoration] = value;
}
void Compiler::set_extended_member_decoration(uint32_t type, uint32_t index, ExtendedDecorations decoration,
uint32_t value)
{
ir.meta[type].members.resize(max(ir.meta[type].members.size(), size_t(index) + 1));
auto &dec = ir.meta[type].members[index];
dec.extended.flags.set(decoration);
dec.extended.values[decoration] = value;
}
static uint32_t get_default_extended_decoration(ExtendedDecorations decoration)
{
switch (decoration)
{
case SPIRVCrossDecorationResourceIndexPrimary:
case SPIRVCrossDecorationResourceIndexSecondary:
case SPIRVCrossDecorationInterfaceMemberIndex:
return ~(0u);
default:
return 0;
}
}
uint32_t Compiler::get_extended_decoration(uint32_t id, ExtendedDecorations decoration) const
{
auto *m = ir.find_meta(id);
if (!m)
return 0;
auto &dec = m->decoration;
if (!dec.extended.flags.get(decoration))
return get_default_extended_decoration(decoration);
return dec.extended.values[decoration];
}
uint32_t Compiler::get_extended_member_decoration(uint32_t type, uint32_t index, ExtendedDecorations decoration) const
{
auto *m = ir.find_meta(type);
if (!m)
return 0;
if (index >= m->members.size())
return 0;
auto &dec = m->members[index];
if (!dec.extended.flags.get(decoration))
return get_default_extended_decoration(decoration);
return dec.extended.values[decoration];
}
bool Compiler::has_extended_decoration(uint32_t id, ExtendedDecorations decoration) const
{
auto *m = ir.find_meta(id);
if (!m)
return false;
auto &dec = m->decoration;
return dec.extended.flags.get(decoration);
}
bool Compiler::has_extended_member_decoration(uint32_t type, uint32_t index, ExtendedDecorations decoration) const
{
auto *m = ir.find_meta(type);
if (!m)
return false;
if (index >= m->members.size())
return false;
auto &dec = m->members[index];
return dec.extended.flags.get(decoration);
}
void Compiler::unset_extended_decoration(uint32_t id, ExtendedDecorations decoration)
{
auto &dec = ir.meta[id].decoration;
dec.extended.flags.clear(decoration);
dec.extended.values[decoration] = 0;
}
void Compiler::unset_extended_member_decoration(uint32_t type, uint32_t index, ExtendedDecorations decoration)
{
ir.meta[type].members.resize(max(ir.meta[type].members.size(), size_t(index) + 1));
auto &dec = ir.meta[type].members[index];
dec.extended.flags.clear(decoration);
dec.extended.values[decoration] = 0;
}
StorageClass Compiler::get_storage_class(uint32_t id) const
{
return get<SPIRVariable>(id).storage;
}
const std::string &Compiler::get_name(uint32_t id) const
{
return ir.get_name(id);
}
const std::string Compiler::get_fallback_name(uint32_t id) const
{
return join("_", id);
}
const std::string Compiler::get_block_fallback_name(uint32_t id) const
{
auto &var = get<SPIRVariable>(id);
if (get_name(id).empty())
return join("_", get<SPIRType>(var.basetype).self, "_", id);
else
return get_name(id);
}
const Bitset &Compiler::get_decoration_bitset(uint32_t id) const
{
return ir.get_decoration_bitset(id);
}
bool Compiler::has_decoration(uint32_t id, Decoration decoration) const
{
return ir.has_decoration(id, decoration);
}
const string &Compiler::get_decoration_string(uint32_t id, Decoration decoration) const
{
return ir.get_decoration_string(id, decoration);
}
const string &Compiler::get_member_decoration_string(uint32_t id, uint32_t index, Decoration decoration) const
{
return ir.get_member_decoration_string(id, index, decoration);
}
uint32_t Compiler::get_decoration(uint32_t id, Decoration decoration) const
{
return ir.get_decoration(id, decoration);
}
void Compiler::unset_decoration(uint32_t id, Decoration decoration)
{
ir.unset_decoration(id, decoration);
}
bool Compiler::get_binary_offset_for_decoration(uint32_t id, spv::Decoration decoration, uint32_t &word_offset) const
{
auto *m = ir.find_meta(id);
if (!m)
return false;
auto &word_offsets = m->decoration_word_offset;
auto itr = word_offsets.find(decoration);
if (itr == end(word_offsets))
return false;
word_offset = itr->second;
return true;
}
bool Compiler::block_is_loop_candidate(const SPIRBlock &block, SPIRBlock::Method method) const
{
// Tried and failed.
if (block.disable_block_optimization || block.complex_continue)
return false;
if (method == SPIRBlock::MergeToSelectForLoop || method == SPIRBlock::MergeToSelectContinueForLoop)
{
// Try to detect common for loop pattern
// which the code backend can use to create cleaner code.
// for(;;) { if (cond) { some_body; } else { break; } }
// is the pattern we're looking for.
const auto *false_block = maybe_get<SPIRBlock>(block.false_block);
const auto *true_block = maybe_get<SPIRBlock>(block.true_block);
const auto *merge_block = maybe_get<SPIRBlock>(block.merge_block);
bool false_block_is_merge = block.false_block == block.merge_block ||
(false_block && merge_block && execution_is_noop(*false_block, *merge_block));
bool true_block_is_merge = block.true_block == block.merge_block ||
(true_block && merge_block && execution_is_noop(*true_block, *merge_block));
bool positive_candidate =
block.true_block != block.merge_block && block.true_block != block.self && false_block_is_merge;
bool negative_candidate =
block.false_block != block.merge_block && block.false_block != block.self && true_block_is_merge;
bool ret = block.terminator == SPIRBlock::Select && block.merge == SPIRBlock::MergeLoop &&
(positive_candidate || negative_candidate);
if (ret && positive_candidate && method == SPIRBlock::MergeToSelectContinueForLoop)
ret = block.true_block == block.continue_block;
else if (ret && negative_candidate && method == SPIRBlock::MergeToSelectContinueForLoop)
ret = block.false_block == block.continue_block;
// If we have OpPhi which depends on branches which came from our own block,
// we need to flush phi variables in else block instead of a trivial break,
// so we cannot assume this is a for loop candidate.
if (ret)
{
for (auto &phi : block.phi_variables)
if (phi.parent == block.self)
return false;
auto *merge = maybe_get<SPIRBlock>(block.merge_block);
if (merge)
for (auto &phi : merge->phi_variables)
if (phi.parent == block.self)
return false;
}
return ret;
}
else if (method == SPIRBlock::MergeToDirectForLoop)
{
// Empty loop header that just sets up merge target
// and branches to loop body.
bool ret = block.terminator == SPIRBlock::Direct && block.merge == SPIRBlock::MergeLoop && block.ops.empty();
if (!ret)
return false;
auto &child = get<SPIRBlock>(block.next_block);
const auto *false_block = maybe_get<SPIRBlock>(child.false_block);
const auto *true_block = maybe_get<SPIRBlock>(child.true_block);
const auto *merge_block = maybe_get<SPIRBlock>(block.merge_block);
bool false_block_is_merge = child.false_block == block.merge_block ||
(false_block && merge_block && execution_is_noop(*false_block, *merge_block));
bool true_block_is_merge = child.true_block == block.merge_block ||
(true_block && merge_block && execution_is_noop(*true_block, *merge_block));
bool positive_candidate =
child.true_block != block.merge_block && child.true_block != block.self && false_block_is_merge;
bool negative_candidate =
child.false_block != block.merge_block && child.false_block != block.self && true_block_is_merge;
ret = child.terminator == SPIRBlock::Select && child.merge == SPIRBlock::MergeNone &&
(positive_candidate || negative_candidate);
// If we have OpPhi which depends on branches which came from our own block,
// we need to flush phi variables in else block instead of a trivial break,
// so we cannot assume this is a for loop candidate.
if (ret)
{
for (auto &phi : block.phi_variables)
if (phi.parent == block.self || phi.parent == child.self)
return false;
for (auto &phi : child.phi_variables)
if (phi.parent == block.self)
return false;
auto *merge = maybe_get<SPIRBlock>(block.merge_block);
if (merge)
for (auto &phi : merge->phi_variables)
if (phi.parent == block.self || phi.parent == child.false_block)
return false;
}
return ret;
}
else
return false;
}
bool Compiler::block_is_outside_flow_control_from_block(const SPIRBlock &from, const SPIRBlock &to)
{
auto *start = &from;
if (start->self == to.self)
return true;
// Break cycles.
if (is_continue(start->self))
return false;
// If our select block doesn't merge, we must break or continue in these blocks,
// so if continues occur branchless within these blocks, consider them branchless as well.
// This is typically used for loop control.
if (start->terminator == SPIRBlock::Select && start->merge == SPIRBlock::MergeNone &&
(block_is_outside_flow_control_from_block(get<SPIRBlock>(start->true_block), to) ||
block_is_outside_flow_control_from_block(get<SPIRBlock>(start->false_block), to)))
{
return true;
}
else if (start->merge_block && block_is_outside_flow_control_from_block(get<SPIRBlock>(start->merge_block), to))
{
return true;
}
else if (start->next_block && block_is_outside_flow_control_from_block(get<SPIRBlock>(start->next_block), to))
{
return true;
}
else
return false;
}
bool Compiler::execution_is_noop(const SPIRBlock &from, const SPIRBlock &to) const
{
if (!execution_is_branchless(from, to))
return false;
auto *start = &from;
for (;;)
{
if (start->self == to.self)
return true;
if (!start->ops.empty())
return false;
auto &next = get<SPIRBlock>(start->next_block);
// Flushing phi variables does not count as noop.
for (auto &phi : next.phi_variables)
if (phi.parent == start->self)
return false;
start = &next;
}
}
bool Compiler::execution_is_branchless(const SPIRBlock &from, const SPIRBlock &to) const
{
auto *start = &from;
for (;;)
{
if (start->self == to.self)
return true;
if (start->terminator == SPIRBlock::Direct && start->merge == SPIRBlock::MergeNone)
start = &get<SPIRBlock>(start->next_block);
else
return false;
}
}
bool Compiler::execution_is_direct_branch(const SPIRBlock &from, const SPIRBlock &to) const
{
return from.terminator == SPIRBlock::Direct && from.merge == SPIRBlock::MergeNone && from.next_block == to.self;
}
SPIRBlock::ContinueBlockType Compiler::continue_block_type(const SPIRBlock &block) const
{
// The block was deemed too complex during code emit, pick conservative fallback paths.
if (block.complex_continue)
return SPIRBlock::ComplexLoop;
// In older glslang output continue block can be equal to the loop header.
// In this case, execution is clearly branchless, so just assume a while loop header here.
if (block.merge == SPIRBlock::MergeLoop)
return SPIRBlock::WhileLoop;
if (block.loop_dominator == SPIRBlock::NoDominator)
{
// Continue block is never reached from CFG.
return SPIRBlock::ComplexLoop;
}
auto &dominator = get<SPIRBlock>(block.loop_dominator);
if (execution_is_noop(block, dominator))
return SPIRBlock::WhileLoop;
else if (execution_is_branchless(block, dominator))
return SPIRBlock::ForLoop;
else
{
const auto *false_block = maybe_get<SPIRBlock>(block.false_block);
const auto *true_block = maybe_get<SPIRBlock>(block.true_block);
const auto *merge_block = maybe_get<SPIRBlock>(dominator.merge_block);
// If we need to flush Phi in this block, we cannot have a DoWhile loop.
bool flush_phi_to_false = false_block && flush_phi_required(block.self, block.false_block);
bool flush_phi_to_true = true_block && flush_phi_required(block.self, block.true_block);
if (flush_phi_to_false || flush_phi_to_true)
return SPIRBlock::ComplexLoop;
bool positive_do_while = block.true_block == dominator.self &&
(block.false_block == dominator.merge_block ||
(false_block && merge_block && execution_is_noop(*false_block, *merge_block)));
bool negative_do_while = block.false_block == dominator.self &&
(block.true_block == dominator.merge_block ||
(true_block && merge_block && execution_is_noop(*true_block, *merge_block)));
if (block.merge == SPIRBlock::MergeNone && block.terminator == SPIRBlock::Select &&
(positive_do_while || negative_do_while))
{
return SPIRBlock::DoWhileLoop;
}
else
return SPIRBlock::ComplexLoop;
}
}
bool Compiler::traverse_all_reachable_opcodes(const SPIRBlock &block, OpcodeHandler &handler) const
{
handler.set_current_block(block);
// Ideally, perhaps traverse the CFG instead of all blocks in order to eliminate dead blocks,
// but this shouldn't be a problem in practice unless the SPIR-V is doing insane things like recursing
// inside dead blocks ...
for (auto &i : block.ops)
{
auto ops = stream(i);
auto op = static_cast<Op>(i.op);
if (!handler.handle(op, ops, i.length))
return false;
if (op == OpFunctionCall)
{
auto &func = get<SPIRFunction>(ops[2]);
if (handler.follow_function_call(func))
{
if (!handler.begin_function_scope(ops, i.length))
return false;
if (!traverse_all_reachable_opcodes(get<SPIRFunction>(ops[2]), handler))
return false;
if (!handler.end_function_scope(ops, i.length))
return false;
}
}
}
return true;
}
bool Compiler::traverse_all_reachable_opcodes(const SPIRFunction &func, OpcodeHandler &handler) const
{
for (auto block : func.blocks)
if (!traverse_all_reachable_opcodes(get<SPIRBlock>(block), handler))
return false;
return true;
}
uint32_t Compiler::type_struct_member_offset(const SPIRType &type, uint32_t index) const
{
auto *type_meta = ir.find_meta(type.self);
if (type_meta)
{
// Decoration must be set in valid SPIR-V, otherwise throw.
auto &dec = type_meta->members[index];
if (dec.decoration_flags.get(DecorationOffset))
return dec.offset;
else
SPIRV_CROSS_THROW("Struct member does not have Offset set.");
}
else
SPIRV_CROSS_THROW("Struct member does not have Offset set.");
}
uint32_t Compiler::type_struct_member_array_stride(const SPIRType &type, uint32_t index) const
{
auto *type_meta = ir.find_meta(type.member_types[index]);
if (type_meta)
{
// Decoration must be set in valid SPIR-V, otherwise throw.
// ArrayStride is part of the array type not OpMemberDecorate.
auto &dec = type_meta->decoration;
if (dec.decoration_flags.get(DecorationArrayStride))
return dec.array_stride;
else
SPIRV_CROSS_THROW("Struct member does not have ArrayStride set.");
}
else
SPIRV_CROSS_THROW("Struct member does not have ArrayStride set.");
}
uint32_t Compiler::type_struct_member_matrix_stride(const SPIRType &type, uint32_t index) const
{
auto *type_meta = ir.find_meta(type.self);
if (type_meta)
{
// Decoration must be set in valid SPIR-V, otherwise throw.
// MatrixStride is part of OpMemberDecorate.
auto &dec = type_meta->members[index];
if (dec.decoration_flags.get(DecorationMatrixStride))
return dec.matrix_stride;
else
SPIRV_CROSS_THROW("Struct member does not have MatrixStride set.");
}
else
SPIRV_CROSS_THROW("Struct member does not have MatrixStride set.");
}
size_t Compiler::get_declared_struct_size(const SPIRType &type) const
{
if (type.member_types.empty())
SPIRV_CROSS_THROW("Declared struct in block cannot be empty.");
uint32_t last = uint32_t(type.member_types.size() - 1);
size_t offset = type_struct_member_offset(type, last);
size_t size = get_declared_struct_member_size(type, last);
return offset + size;
}
size_t Compiler::get_declared_struct_size_runtime_array(const SPIRType &type, size_t array_size) const
{
if (type.member_types.empty())
SPIRV_CROSS_THROW("Declared struct in block cannot be empty.");
size_t size = get_declared_struct_size(type);
auto &last_type = get<SPIRType>(type.member_types.back());
if (!last_type.array.empty() && last_type.array_size_literal[0] && last_type.array[0] == 0) // Runtime array
size += array_size * type_struct_member_array_stride(type, uint32_t(type.member_types.size() - 1));
return size;
}
size_t Compiler::get_declared_struct_member_size(const SPIRType &struct_type, uint32_t index) const
{
if (struct_type.member_types.empty())
SPIRV_CROSS_THROW("Declared struct in block cannot be empty.");
auto &flags = get_member_decoration_bitset(struct_type.self, index);
auto &type = get<SPIRType>(struct_type.member_types[index]);
switch (type.basetype)
{
case SPIRType::Unknown:
case SPIRType::Void:
case SPIRType::Boolean: // Bools are purely logical, and cannot be used for externally visible types.
case SPIRType::AtomicCounter:
case SPIRType::Image:
case SPIRType::SampledImage:
case SPIRType::Sampler:
SPIRV_CROSS_THROW("Querying size for object with opaque size.");
default:
break;
}
if (!type.array.empty())
{
// For arrays, we can use ArrayStride to get an easy check.
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) * array_size;
}
else if (type.basetype == SPIRType::Struct)
{
return get_declared_struct_size(type);
}
else
{
unsigned vecsize = type.vecsize;
unsigned columns = type.columns;
// Vectors.
if (columns == 1)
{
size_t component_size = type.width / 8;
return vecsize * component_size;
}
else
{
uint32_t matrix_stride = type_struct_member_matrix_stride(struct_type, index);
// Per SPIR-V spec, matrices must be tightly packed and aligned up for vec3 accesses.
if (flags.get(DecorationRowMajor))
return matrix_stride * vecsize;
else if (flags.get(DecorationColMajor))
return matrix_stride * columns;
else
SPIRV_CROSS_THROW("Either row-major or column-major must be declared for matrices.");
}
}
}
bool Compiler::BufferAccessHandler::handle(Op opcode, const uint32_t *args, uint32_t length)
{
if (opcode != OpAccessChain && opcode != OpInBoundsAccessChain && opcode != OpPtrAccessChain)
return true;
bool ptr_chain = (opcode == OpPtrAccessChain);
// Invalid SPIR-V.
if (length < (ptr_chain ? 5u : 4u))
return false;
if (args[2] != id)
return true;
// Don't bother traversing the entire access chain tree yet.
// If we access a struct member, assume we access the entire member.
uint32_t index = compiler.get<SPIRConstant>(args[ptr_chain ? 4 : 3]).scalar();
// Seen this index already.
if (seen.find(index) != end(seen))
return true;
seen.insert(index);
auto &type = compiler.expression_type(id);
uint32_t offset = compiler.type_struct_member_offset(type, index);
size_t range;
// If we have another member in the struct, deduce the range by looking at the next member.
// This is okay since structs in SPIR-V can have padding, but Offset decoration must be
// monotonically increasing.
// Of course, this doesn't take into account if the SPIR-V for some reason decided to add
// very large amounts of padding, but that's not really a big deal.
if (index + 1 < type.member_types.size())
{
range = compiler.type_struct_member_offset(type, index + 1) - offset;
}
else
{
// No padding, so just deduce it from the size of the member directly.
range = compiler.get_declared_struct_member_size(type, index);
}
ranges.push_back({ index, offset, range });
return true;
}
SmallVector<BufferRange> Compiler::get_active_buffer_ranges(uint32_t id) const
{
SmallVector<BufferRange> ranges;
BufferAccessHandler handler(*this, ranges, id);
traverse_all_reachable_opcodes(get<SPIRFunction>(ir.default_entry_point), handler);
return ranges;
}
bool Compiler::types_are_logically_equivalent(const SPIRType &a, const SPIRType &b) const
{
if (a.basetype != b.basetype)
return false;
if (a.width != b.width)
return false;
if (a.vecsize != b.vecsize)
return false;
if (a.columns != b.columns)
return false;
if (a.array.size() != b.array.size())
return false;
size_t array_count = a.array.size();
if (array_count && memcmp(a.array.data(), b.array.data(), array_count * sizeof(uint32_t)) != 0)
return false;
if (a.basetype == SPIRType::Image || a.basetype == SPIRType::SampledImage)
{
if (memcmp(&a.image, &b.image, sizeof(SPIRType::Image)) != 0)
return false;
}
if (a.member_types.size() != b.member_types.size())
return false;
size_t member_types = a.member_types.size();
for (size_t i = 0; i < member_types; i++)
{
if (!types_are_logically_equivalent(get<SPIRType>(a.member_types[i]), get<SPIRType>(b.member_types[i])))
return false;
}
return true;
}
const Bitset &Compiler::get_execution_mode_bitset() const
{
return get_entry_point().flags;
}
void Compiler::set_execution_mode(ExecutionMode mode, uint32_t arg0, uint32_t arg1, uint32_t arg2)
{
auto &execution = get_entry_point();
execution.flags.set(mode);
switch (mode)
{
case ExecutionModeLocalSize:
execution.workgroup_size.x = arg0;
execution.workgroup_size.y = arg1;
execution.workgroup_size.z = arg2;
break;
case ExecutionModeInvocations:
execution.invocations = arg0;
break;
case ExecutionModeOutputVertices:
execution.output_vertices = arg0;
break;
default:
break;
}
}
void Compiler::unset_execution_mode(ExecutionMode mode)
{
auto &execution = get_entry_point();
execution.flags.clear(mode);
}
uint32_t Compiler::get_work_group_size_specialization_constants(SpecializationConstant &x, SpecializationConstant &y,
SpecializationConstant &z) const
{
auto &execution = get_entry_point();
x = { 0, 0 };
y = { 0, 0 };
z = { 0, 0 };
if (execution.workgroup_size.constant != 0)
{
auto &c = get<SPIRConstant>(execution.workgroup_size.constant);
if (c.m.c[0].id[0] != 0)
{
x.id = c.m.c[0].id[0];
x.constant_id = get_decoration(c.m.c[0].id[0], DecorationSpecId);
}
if (c.m.c[0].id[1] != 0)
{
y.id = c.m.c[0].id[1];
y.constant_id = get_decoration(c.m.c[0].id[1], DecorationSpecId);
}
if (c.m.c[0].id[2] != 0)
{
z.id = c.m.c[0].id[2];
z.constant_id = get_decoration(c.m.c[0].id[2], DecorationSpecId);
}
}
return execution.workgroup_size.constant;
}
uint32_t Compiler::get_execution_mode_argument(spv::ExecutionMode mode, uint32_t index) const
{
auto &execution = get_entry_point();
switch (mode)
{
case ExecutionModeLocalSize:
switch (index)
{
case 0:
return execution.workgroup_size.x;
case 1:
return execution.workgroup_size.y;
case 2:
return execution.workgroup_size.z;
default:
return 0;
}
case ExecutionModeInvocations:
return execution.invocations;
case ExecutionModeOutputVertices:
return execution.output_vertices;
default:
return 0;
}
}
ExecutionModel Compiler::get_execution_model() const
{
auto &execution = get_entry_point();
return execution.model;
}
bool Compiler::is_tessellation_shader(ExecutionModel model)
{
return model == ExecutionModelTessellationControl || model == ExecutionModelTessellationEvaluation;
}
bool Compiler::is_tessellation_shader() const
{
return is_tessellation_shader(get_execution_model());
}
void Compiler::set_remapped_variable_state(uint32_t id, bool remap_enable)
{
get<SPIRVariable>(id).remapped_variable = remap_enable;
}
bool Compiler::get_remapped_variable_state(uint32_t id) const
{
return get<SPIRVariable>(id).remapped_variable;
}
void Compiler::set_subpass_input_remapped_components(uint32_t id, uint32_t components)
{
get<SPIRVariable>(id).remapped_components = components;
}
uint32_t Compiler::get_subpass_input_remapped_components(uint32_t id) const
{
return get<SPIRVariable>(id).remapped_components;
}
void Compiler::add_implied_read_expression(SPIRExpression &e, uint32_t source)
{
auto itr = find(begin(e.implied_read_expressions), end(e.implied_read_expressions), source);
if (itr == end(e.implied_read_expressions))
e.implied_read_expressions.push_back(source);
}
void Compiler::add_implied_read_expression(SPIRAccessChain &e, uint32_t source)
{
auto itr = find(begin(e.implied_read_expressions), end(e.implied_read_expressions), source);
if (itr == end(e.implied_read_expressions))
e.implied_read_expressions.push_back(source);
}
void Compiler::inherit_expression_dependencies(uint32_t dst, uint32_t source_expression)
{
// Don't inherit any expression dependencies if the expression in dst
// is not a forwarded temporary.
if (forwarded_temporaries.find(dst) == end(forwarded_temporaries) ||
forced_temporaries.find(dst) != end(forced_temporaries))
{
return;
}
auto &e = get<SPIRExpression>(dst);
auto *phi = maybe_get<SPIRVariable>(source_expression);
if (phi && phi->phi_variable)
{
// We have used a phi variable, which can change at the end of the block,
// so make sure we take a dependency on this phi variable.
phi->dependees.push_back(dst);
}
auto *s = maybe_get<SPIRExpression>(source_expression);
if (!s)
return;
auto &e_deps = e.expression_dependencies;
auto &s_deps = s->expression_dependencies;
// If we depend on a expression, we also depend on all sub-dependencies from source.
e_deps.push_back(source_expression);
e_deps.insert(end(e_deps), begin(s_deps), end(s_deps));
// Eliminate duplicated dependencies.
sort(begin(e_deps), end(e_deps));
e_deps.erase(unique(begin(e_deps), end(e_deps)), end(e_deps));
}
SmallVector<EntryPoint> Compiler::get_entry_points_and_stages() const
{
SmallVector<EntryPoint> entries;
for (auto &entry : ir.entry_points)
entries.push_back({ entry.second.orig_name, entry.second.model });
return entries;
}
void Compiler::rename_entry_point(const std::string &old_name, const std::string &new_name, spv::ExecutionModel model)
{
auto &entry = get_entry_point(old_name, model);
entry.orig_name = new_name;
entry.name = new_name;
}
void Compiler::set_entry_point(const std::string &name, spv::ExecutionModel model)
{
auto &entry = get_entry_point(name, model);
ir.default_entry_point = entry.self;
}
SPIREntryPoint &Compiler::get_first_entry_point(const std::string &name)
{
auto itr = find_if(
begin(ir.entry_points), end(ir.entry_points),
[&](const std::pair<uint32_t, SPIREntryPoint> &entry) -> bool { return entry.second.orig_name == name; });
if (itr == end(ir.entry_points))
SPIRV_CROSS_THROW("Entry point does not exist.");
return itr->second;
}
const SPIREntryPoint &Compiler::get_first_entry_point(const std::string &name) const
{
auto itr = find_if(
begin(ir.entry_points), end(ir.entry_points),
[&](const std::pair<uint32_t, SPIREntryPoint> &entry) -> bool { return entry.second.orig_name == name; });
if (itr == end(ir.entry_points))
SPIRV_CROSS_THROW("Entry point does not exist.");
return itr->second;
}
SPIREntryPoint &Compiler::get_entry_point(const std::string &name, ExecutionModel model)
{
auto itr = find_if(begin(ir.entry_points), end(ir.entry_points),
[&](const std::pair<uint32_t, SPIREntryPoint> &entry) -> bool {
return entry.second.orig_name == name && entry.second.model == model;
});
if (itr == end(ir.entry_points))
SPIRV_CROSS_THROW("Entry point does not exist.");
return itr->second;
}
const SPIREntryPoint &Compiler::get_entry_point(const std::string &name, ExecutionModel model) const
{
auto itr = find_if(begin(ir.entry_points), end(ir.entry_points),
[&](const std::pair<uint32_t, SPIREntryPoint> &entry) -> bool {
return entry.second.orig_name == name && entry.second.model == model;
});
if (itr == end(ir.entry_points))
SPIRV_CROSS_THROW("Entry point does not exist.");
return itr->second;
}
const string &Compiler::get_cleansed_entry_point_name(const std::string &name, ExecutionModel model) const
{
return get_entry_point(name, model).name;
}
const SPIREntryPoint &Compiler::get_entry_point() const
{
return ir.entry_points.find(ir.default_entry_point)->second;
}
SPIREntryPoint &Compiler::get_entry_point()
{
return ir.entry_points.find(ir.default_entry_point)->second;
}
bool Compiler::interface_variable_exists_in_entry_point(uint32_t id) const
{
auto &var = get<SPIRVariable>(id);
if (var.storage != StorageClassInput && var.storage != StorageClassOutput &&
var.storage != StorageClassUniformConstant)
SPIRV_CROSS_THROW("Only Input, Output variables and Uniform constants are part of a shader linking interface.");
// This is to avoid potential problems with very old glslang versions which did
// not emit input/output interfaces properly.
// We can assume they only had a single entry point, and single entry point
// shaders could easily be assumed to use every interface variable anyways.
if (ir.entry_points.size() <= 1)
return true;
auto &execution = get_entry_point();
return find(begin(execution.interface_variables), end(execution.interface_variables), id) !=
end(execution.interface_variables);
}
void Compiler::CombinedImageSamplerHandler::push_remap_parameters(const SPIRFunction &func, const uint32_t *args,
uint32_t length)
{
// If possible, pipe through a remapping table so that parameters know
// which variables they actually bind to in this scope.
unordered_map<uint32_t, uint32_t> remapping;
for (uint32_t i = 0; i < length; i++)
remapping[func.arguments[i].id] = remap_parameter(args[i]);
parameter_remapping.push(move(remapping));
}
void Compiler::CombinedImageSamplerHandler::pop_remap_parameters()
{
parameter_remapping.pop();
}
uint32_t Compiler::CombinedImageSamplerHandler::remap_parameter(uint32_t id)
{
auto *var = compiler.maybe_get_backing_variable(id);
if (var)
id = var->self;
if (parameter_remapping.empty())
return id;
auto &remapping = parameter_remapping.top();
auto itr = remapping.find(id);
if (itr != end(remapping))
return itr->second;
else
return id;
}
bool Compiler::CombinedImageSamplerHandler::begin_function_scope(const uint32_t *args, uint32_t length)
{
if (length < 3)
return false;
auto &callee = compiler.get<SPIRFunction>(args[2]);
args += 3;
length -= 3;
push_remap_parameters(callee, args, length);
functions.push(&callee);
return true;
}
bool Compiler::CombinedImageSamplerHandler::end_function_scope(const uint32_t *args, uint32_t length)
{
if (length < 3)
return false;
auto &callee = compiler.get<SPIRFunction>(args[2]);
args += 3;
// There are two types of cases we have to handle,
// a callee might call sampler2D(texture2D, sampler) directly where
// one or more parameters originate from parameters.
// Alternatively, we need to provide combined image samplers to our callees,
// and in this case we need to add those as well.
pop_remap_parameters();
// Our callee has now been processed at least once.
// No point in doing it again.
callee.do_combined_parameters = false;
auto &params = functions.top()->combined_parameters;
functions.pop();
if (functions.empty())
return true;
auto &caller = *functions.top();
if (caller.do_combined_parameters)
{
for (auto &param : params)
{
uint32_t image_id = param.global_image ? param.image_id : args[param.image_id];
uint32_t sampler_id = param.global_sampler ? param.sampler_id : args[param.sampler_id];
auto *i = compiler.maybe_get_backing_variable(image_id);
auto *s = compiler.maybe_get_backing_variable(sampler_id);
if (i)
image_id = i->self;
if (s)
sampler_id = s->self;
register_combined_image_sampler(caller, image_id, sampler_id, param.depth);
}
}
return true;
}
void Compiler::CombinedImageSamplerHandler::register_combined_image_sampler(SPIRFunction &caller, uint32_t image_id,
uint32_t sampler_id, bool depth)
{
// We now have a texture ID and a sampler ID which will either be found as a global
// or a parameter in our own function. If both are global, they will not need a parameter,
// otherwise, add it to our list.
SPIRFunction::CombinedImageSamplerParameter param = {
0u, image_id, sampler_id, true, true, depth,
};
auto texture_itr = find_if(begin(caller.arguments), end(caller.arguments),
[image_id](const SPIRFunction::Parameter &p) { return p.id == image_id; });
auto sampler_itr = find_if(begin(caller.arguments), end(caller.arguments),
[sampler_id](const SPIRFunction::Parameter &p) { return p.id == sampler_id; });
if (texture_itr != end(caller.arguments))
{
param.global_image = false;
param.image_id = uint32_t(texture_itr - begin(caller.arguments));
}
if (sampler_itr != end(caller.arguments))
{
param.global_sampler = false;
param.sampler_id = uint32_t(sampler_itr - begin(caller.arguments));
}
if (param.global_image && param.global_sampler)
return;
auto itr = find_if(begin(caller.combined_parameters), end(caller.combined_parameters),
[&param](const SPIRFunction::CombinedImageSamplerParameter &p) {
return param.image_id == p.image_id && param.sampler_id == p.sampler_id &&
param.global_image == p.global_image && param.global_sampler == p.global_sampler;
});
if (itr == end(caller.combined_parameters))
{
uint32_t id = compiler.ir.increase_bound_by(3);
auto type_id = id + 0;
auto ptr_type_id = id + 1;
auto combined_id = id + 2;
auto &base = compiler.expression_type(image_id);
auto &type = compiler.set<SPIRType>(type_id);
auto &ptr_type = compiler.set<SPIRType>(ptr_type_id);
type = base;
type.self = type_id;
type.basetype = SPIRType::SampledImage;
type.pointer = false;
type.storage = StorageClassGeneric;
type.image.depth = depth;
ptr_type = type;
ptr_type.pointer = true;
ptr_type.storage = StorageClassUniformConstant;
ptr_type.parent_type = type_id;
// Build new variable.
compiler.set<SPIRVariable>(combined_id, ptr_type_id, StorageClassFunction, 0);
// Inherit RelaxedPrecision (and potentially other useful flags if deemed relevant).
auto &new_flags = compiler.ir.meta[combined_id].decoration.decoration_flags;
auto &old_flags = compiler.ir.meta[sampler_id].decoration.decoration_flags;
new_flags.reset();
if (old_flags.get(DecorationRelaxedPrecision))
new_flags.set(DecorationRelaxedPrecision);
param.id = combined_id;
compiler.set_name(combined_id,
join("SPIRV_Cross_Combined", compiler.to_name(image_id), compiler.to_name(sampler_id)));
caller.combined_parameters.push_back(param);
caller.shadow_arguments.push_back({ ptr_type_id, combined_id, 0u, 0u, true });
}
}
bool Compiler::DummySamplerForCombinedImageHandler::handle(Op opcode, const uint32_t *args, uint32_t length)
{
if (need_dummy_sampler)
{
// No need to traverse further, we know the result.
return false;
}
switch (opcode)
{
case OpLoad:
{
if (length < 3)
return false;
uint32_t result_type = args[0];
auto &type = compiler.get<SPIRType>(result_type);
bool separate_image =
type.basetype == SPIRType::Image && type.image.sampled == 1 && type.image.dim != DimBuffer;
// If not separate image, don't bother.
if (!separate_image)
return true;
uint32_t id = args[1];
uint32_t ptr = args[2];
compiler.set<SPIRExpression>(id, "", result_type, true);
compiler.register_read(id, ptr, true);
break;
}
case OpImageFetch:
case OpImageQuerySizeLod:
case OpImageQuerySize:
case OpImageQueryLevels:
case OpImageQuerySamples:
{
// If we are fetching or querying LOD from a plain OpTypeImage, we must pre-combine with our dummy sampler.
auto *var = compiler.maybe_get_backing_variable(args[2]);
if (var)
{
auto &type = compiler.get<SPIRType>(var->basetype);
if (type.basetype == SPIRType::Image && type.image.sampled == 1 && type.image.dim != DimBuffer)
need_dummy_sampler = true;
}
break;
}
case OpInBoundsAccessChain:
case OpAccessChain:
case OpPtrAccessChain:
{
if (length < 3)
return false;
uint32_t result_type = args[0];
auto &type = compiler.get<SPIRType>(result_type);
bool separate_image =
type.basetype == SPIRType::Image && type.image.sampled == 1 && type.image.dim != DimBuffer;
if (!separate_image)
return true;
uint32_t id = args[1];
uint32_t ptr = args[2];
compiler.set<SPIRExpression>(id, "", result_type, true);
compiler.register_read(id, ptr, true);
// Other backends might use SPIRAccessChain for this later.
compiler.ir.ids[id].set_allow_type_rewrite();
break;
}
default:
break;
}
return true;
}
bool Compiler::CombinedImageSamplerHandler::handle(Op opcode, const uint32_t *args, uint32_t length)
{
// We need to figure out where samplers and images are loaded from, so do only the bare bones compilation we need.
bool is_fetch = false;
switch (opcode)
{
case OpLoad:
{
if (length < 3)
return false;
uint32_t result_type = args[0];
auto &type = compiler.get<SPIRType>(result_type);
bool separate_image = type.basetype == SPIRType::Image && type.image.sampled == 1;
bool separate_sampler = type.basetype == SPIRType::Sampler;
// If not separate image or sampler, don't bother.
if (!separate_image && !separate_sampler)
return true;
uint32_t id = args[1];
uint32_t ptr = args[2];
compiler.set<SPIRExpression>(id, "", result_type, true);
compiler.register_read(id, ptr, true);
return true;
}
case OpInBoundsAccessChain:
case OpAccessChain:
case OpPtrAccessChain:
{
if (length < 3)
return false;
// Technically, it is possible to have arrays of textures and arrays of samplers and combine them, but this becomes essentially
// impossible to implement, since we don't know which concrete sampler we are accessing.
// One potential way is to create a combinatorial explosion where N textures and M samplers are combined into N * M sampler2Ds,
// but this seems ridiculously complicated for a problem which is easy to work around.
// Checking access chains like this assumes we don't have samplers or textures inside uniform structs, but this makes no sense.
uint32_t result_type = args[0];
auto &type = compiler.get<SPIRType>(result_type);
bool separate_image = type.basetype == SPIRType::Image && type.image.sampled == 1;
bool separate_sampler = type.basetype == SPIRType::Sampler;
if (separate_sampler)
SPIRV_CROSS_THROW(
"Attempting to use arrays or structs of separate samplers. This is not possible to statically "
"remap to plain GLSL.");
if (separate_image)
{
uint32_t id = args[1];
uint32_t ptr = args[2];
compiler.set<SPIRExpression>(id, "", result_type, true);
compiler.register_read(id, ptr, true);
}
return true;
}
case OpImageFetch:
case OpImageQuerySizeLod:
case OpImageQuerySize:
case OpImageQueryLevels:
case OpImageQuerySamples:
{
// If we are fetching from a plain OpTypeImage or querying LOD, we must pre-combine with our dummy sampler.
auto *var = compiler.maybe_get_backing_variable(args[2]);
if (!var)
return true;
auto &type = compiler.get<SPIRType>(var->basetype);
if (type.basetype == SPIRType::Image && type.image.sampled == 1 && type.image.dim != DimBuffer)
{
if (compiler.dummy_sampler_id == 0)
SPIRV_CROSS_THROW("texelFetch without sampler was found, but no dummy sampler has been created with "
"build_dummy_sampler_for_combined_images().");
// Do it outside.
is_fetch = true;
break;
}
return true;
}
case OpSampledImage:
// Do it outside.
break;
default:
return true;
}
// Registers sampler2D calls used in case they are parameters so
// that their callees know which combined image samplers to propagate down the call stack.
if (!functions.empty())
{
auto &callee = *functions.top();
if (callee.do_combined_parameters)
{
uint32_t image_id = args[2];
auto *image = compiler.maybe_get_backing_variable(image_id);
if (image)
image_id = image->self;
uint32_t sampler_id = is_fetch ? compiler.dummy_sampler_id : args[3];
auto *sampler = compiler.maybe_get_backing_variable(sampler_id);
if (sampler)
sampler_id = sampler->self;
auto &combined_type = compiler.get<SPIRType>(args[0]);
register_combined_image_sampler(callee, image_id, sampler_id, combined_type.image.depth);
}
}
// For function calls, we need to remap IDs which are function parameters into global variables.
// This information is statically known from the current place in the call stack.
// Function parameters are not necessarily pointers, so if we don't have a backing variable, remapping will know
// which backing variable the image/sample came from.
uint32_t image_id = remap_parameter(args[2]);
uint32_t sampler_id = is_fetch ? compiler.dummy_sampler_id : remap_parameter(args[3]);
auto itr = find_if(begin(compiler.combined_image_samplers), end(compiler.combined_image_samplers),
[image_id, sampler_id](const CombinedImageSampler &combined) {
return combined.image_id == image_id && combined.sampler_id == sampler_id;
});
if (itr == end(compiler.combined_image_samplers))
{
uint32_t sampled_type;
if (is_fetch)
{
// Have to invent the sampled image type.
sampled_type = compiler.ir.increase_bound_by(1);
auto &type = compiler.set<SPIRType>(sampled_type);
type = compiler.expression_type(args[2]);
type.self = sampled_type;
type.basetype = SPIRType::SampledImage;
type.image.depth = false;
}
else
{
sampled_type = args[0];
}
auto id = compiler.ir.increase_bound_by(2);
auto type_id = id + 0;
auto combined_id = id + 1;
// Make a new type, pointer to OpTypeSampledImage, so we can make a variable of this type.
// We will probably have this type lying around, but it doesn't hurt to make duplicates for internal purposes.
auto &type = compiler.set<SPIRType>(type_id);
auto &base = compiler.get<SPIRType>(sampled_type);
type = base;
type.pointer = true;
type.storage = StorageClassUniformConstant;
type.parent_type = type_id;
// Build new variable.
compiler.set<SPIRVariable>(combined_id, type_id, StorageClassUniformConstant, 0);
// Inherit RelaxedPrecision (and potentially other useful flags if deemed relevant).
auto &new_flags = compiler.ir.meta[combined_id].decoration.decoration_flags;
// Fetch inherits precision from the image, not sampler (there is no sampler).
auto &old_flags = compiler.ir.meta[is_fetch ? image_id : sampler_id].decoration.decoration_flags;
new_flags.reset();
if (old_flags.get(DecorationRelaxedPrecision))
new_flags.set(DecorationRelaxedPrecision);
// Propagate the array type for the original image as well.
auto *var = compiler.maybe_get_backing_variable(image_id);
if (var)
{
auto &parent_type = compiler.get<SPIRType>(var->basetype);
type.array = parent_type.array;
type.array_size_literal = parent_type.array_size_literal;
}
compiler.combined_image_samplers.push_back({ combined_id, image_id, sampler_id });
}
return true;
}
uint32_t Compiler::build_dummy_sampler_for_combined_images()
{
DummySamplerForCombinedImageHandler handler(*this);
traverse_all_reachable_opcodes(get<SPIRFunction>(ir.default_entry_point), handler);
if (handler.need_dummy_sampler)
{
uint32_t offset = ir.increase_bound_by(3);
auto type_id = offset + 0;
auto ptr_type_id = offset + 1;
auto var_id = offset + 2;
SPIRType sampler_type;
auto &sampler = set<SPIRType>(type_id);
sampler.basetype = SPIRType::Sampler;
auto &ptr_sampler = set<SPIRType>(ptr_type_id);
ptr_sampler = sampler;
ptr_sampler.self = type_id;
ptr_sampler.storage = StorageClassUniformConstant;
ptr_sampler.pointer = true;
ptr_sampler.parent_type = type_id;
set<SPIRVariable>(var_id, ptr_type_id, StorageClassUniformConstant, 0);
set_name(var_id, "SPIRV_Cross_DummySampler");
dummy_sampler_id = var_id;
return var_id;
}
else
return 0;
}
void Compiler::build_combined_image_samplers()
{
ir.for_each_typed_id<SPIRFunction>([&](uint32_t, SPIRFunction &func) {
func.combined_parameters.clear();
func.shadow_arguments.clear();
func.do_combined_parameters = true;
});
combined_image_samplers.clear();
CombinedImageSamplerHandler handler(*this);
traverse_all_reachable_opcodes(get<SPIRFunction>(ir.default_entry_point), handler);
}
SmallVector<SpecializationConstant> Compiler::get_specialization_constants() const
{
SmallVector<SpecializationConstant> spec_consts;
ir.for_each_typed_id<SPIRConstant>([&](uint32_t, const SPIRConstant &c) {
if (c.specialization && has_decoration(c.self, DecorationSpecId))
spec_consts.push_back({ c.self, get_decoration(c.self, DecorationSpecId) });
});
return spec_consts;
}
SPIRConstant &Compiler::get_constant(uint32_t id)
{
return get<SPIRConstant>(id);
}
const SPIRConstant &Compiler::get_constant(uint32_t id) const
{
return get<SPIRConstant>(id);
}
static bool exists_unaccessed_path_to_return(const CFG &cfg, uint32_t block, const unordered_set<uint32_t> &blocks)
{
// This block accesses the variable.
if (blocks.find(block) != end(blocks))
return false;
// We are at the end of the CFG.
if (cfg.get_succeeding_edges(block).empty())
return true;
// If any of our successors have a path to the end, there exists a path from block.
for (auto &succ : cfg.get_succeeding_edges(block))
if (exists_unaccessed_path_to_return(cfg, succ, blocks))
return true;
return false;
}
void Compiler::analyze_parameter_preservation(
SPIRFunction &entry, const CFG &cfg, const unordered_map<uint32_t, unordered_set<uint32_t>> &variable_to_blocks,
const unordered_map<uint32_t, unordered_set<uint32_t>> &complete_write_blocks)
{
for (auto &arg : entry.arguments)
{
// Non-pointers are always inputs.
auto &type = get<SPIRType>(arg.type);
if (!type.pointer)
continue;
// Opaque argument types are always in
bool potential_preserve;
switch (type.basetype)
{
case SPIRType::Sampler:
case SPIRType::Image:
case SPIRType::SampledImage:
case SPIRType::AtomicCounter:
potential_preserve = false;
break;
default:
potential_preserve = true;
break;
}
if (!potential_preserve)
continue;
auto itr = variable_to_blocks.find(arg.id);
if (itr == end(variable_to_blocks))
{
// Variable is never accessed.
continue;
}
// We have accessed a variable, but there was no complete writes to that variable.
// We deduce that we must preserve the argument.
itr = complete_write_blocks.find(arg.id);
if (itr == end(complete_write_blocks))
{
arg.read_count++;
continue;
}
// If there is a path through the CFG where no block completely writes to the variable, the variable will be in an undefined state
// when the function returns. We therefore need to implicitly preserve the variable in case there are writers in the function.
// Major case here is if a function is
// void foo(int &var) { if (cond) var = 10; }
// Using read/write counts, we will think it's just an out variable, but it really needs to be inout,
// because if we don't write anything whatever we put into the function must return back to the caller.
if (exists_unaccessed_path_to_return(cfg, entry.entry_block, itr->second))
arg.read_count++;
}
}
Compiler::AnalyzeVariableScopeAccessHandler::AnalyzeVariableScopeAccessHandler(Compiler &compiler_,
SPIRFunction &entry_)
: compiler(compiler_)
, entry(entry_)
{
}
bool Compiler::AnalyzeVariableScopeAccessHandler::follow_function_call(const SPIRFunction &)
{
// Only analyze within this function.
return false;
}
void Compiler::AnalyzeVariableScopeAccessHandler::set_current_block(const SPIRBlock &block)
{
current_block = &block;
// If we're branching to a block which uses OpPhi, in GLSL
// this will be a variable write when we branch,
// so we need to track access to these variables as well to
// have a complete picture.
const auto test_phi = [this, &block](uint32_t to) {
auto &next = compiler.get<SPIRBlock>(to);
for (auto &phi : next.phi_variables)
{
if (phi.parent == block.self)
{
accessed_variables_to_block[phi.function_variable].insert(block.self);
// Phi variables are also accessed in our target branch block.
accessed_variables_to_block[phi.function_variable].insert(next.self);
notify_variable_access(phi.local_variable, block.self);
}
}
};
switch (block.terminator)
{
case SPIRBlock::Direct:
notify_variable_access(block.condition, block.self);
test_phi(block.next_block);
break;
case SPIRBlock::Select:
notify_variable_access(block.condition, block.self);
test_phi(block.true_block);
test_phi(block.false_block);
break;
case SPIRBlock::MultiSelect:
notify_variable_access(block.condition, block.self);
for (auto &target : block.cases)
test_phi(target.block);
if (block.default_block)
test_phi(block.default_block);
break;
default:
break;
}
}
void Compiler::AnalyzeVariableScopeAccessHandler::notify_variable_access(uint32_t id, uint32_t block)
{
if (id == 0)
return;
if (id_is_phi_variable(id))
accessed_variables_to_block[id].insert(block);
else if (id_is_potential_temporary(id))
accessed_temporaries_to_block[id].insert(block);
}
bool Compiler::AnalyzeVariableScopeAccessHandler::id_is_phi_variable(uint32_t id) const
{
if (id >= compiler.get_current_id_bound())
return false;
auto *var = compiler.maybe_get<SPIRVariable>(id);
return var && var->phi_variable;
}
bool Compiler::AnalyzeVariableScopeAccessHandler::id_is_potential_temporary(uint32_t id) const
{
if (id >= compiler.get_current_id_bound())
return false;
// Temporaries are not created before we start emitting code.
return compiler.ir.ids[id].empty() || (compiler.ir.ids[id].get_type() == TypeExpression);
}
bool Compiler::AnalyzeVariableScopeAccessHandler::handle(spv::Op op, const uint32_t *args, uint32_t length)
{
// Keep track of the types of temporaries, so we can hoist them out as necessary.
uint32_t result_type, result_id;
if (compiler.instruction_to_result_type(result_type, result_id, op, args, length))
result_id_to_type[result_id] = result_type;
switch (op)
{
case OpStore:
{
if (length < 2)
return false;
uint32_t ptr = args[0];
auto *var = compiler.maybe_get_backing_variable(ptr);
// If we store through an access chain, we have a partial write.
if (var)
{
accessed_variables_to_block[var->self].insert(current_block->self);
if (var->self == ptr)
complete_write_variables_to_block[var->self].insert(current_block->self);
else
partial_write_variables_to_block[var->self].insert(current_block->self);
}
// args[0] might be an access chain we have to track use of.
notify_variable_access(args[0], current_block->self);
// Might try to store a Phi variable here.
notify_variable_access(args[1], current_block->self);
break;
}
case OpAccessChain:
case OpInBoundsAccessChain:
case OpPtrAccessChain:
{
if (length < 3)
return false;
uint32_t ptr = args[2];
auto *var = compiler.maybe_get<SPIRVariable>(ptr);
if (var)
accessed_variables_to_block[var->self].insert(current_block->self);
// args[2] might be another access chain we have to track use of.
for (uint32_t i = 2; i < length; i++)
notify_variable_access(args[i], current_block->self);
// Also keep track of the access chain pointer itself.
// In exceptionally rare cases, we can end up with a case where
// the access chain is generated in the loop body, but is consumed in continue block.
// This means we need complex loop workarounds, and we must detect this via CFG analysis.
notify_variable_access(args[1], current_block->self);
// The result of an access chain is a fixed expression and is not really considered a temporary.
auto &e = compiler.set<SPIRExpression>(args[1], "", args[0], true);
auto *backing_variable = compiler.maybe_get_backing_variable(ptr);
e.loaded_from = backing_variable ? backing_variable->self : 0;
// Other backends might use SPIRAccessChain for this later.
compiler.ir.ids[args[1]].set_allow_type_rewrite();
access_chain_expressions.insert(args[1]);
break;
}
case OpCopyMemory:
{
if (length < 2)
return false;
uint32_t lhs = args[0];
uint32_t rhs = args[1];
auto *var = compiler.maybe_get_backing_variable(lhs);
// If we store through an access chain, we have a partial write.
if (var)
{
accessed_variables_to_block[var->self].insert(current_block->self);
if (var->self == lhs)
complete_write_variables_to_block[var->self].insert(current_block->self);
else
partial_write_variables_to_block[var->self].insert(current_block->self);
}
// args[0:1] might be access chains we have to track use of.
for (uint32_t i = 0; i < 2; i++)
notify_variable_access(args[i], current_block->self);
var = compiler.maybe_get_backing_variable(rhs);
if (var)
accessed_variables_to_block[var