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// Copyright 2018 The SwiftShader Authors. All Rights Reserved.
// 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
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef sw_SpirvShader_hpp
#define sw_SpirvShader_hpp
#include "SamplerCore.hpp"
#include "ShaderCore.hpp"
#include "SpirvBinary.hpp"
#include "SpirvID.hpp"
#include "Device/Config.hpp"
#include "Device/Sampler.hpp"
#include "System/Debug.hpp"
#include "System/Math.hpp"
#include "System/Types.hpp"
#include "Vulkan/VkConfig.hpp"
#include "Vulkan/VkDescriptorSet.hpp"
#include <spirv/unified1/spirv.hpp>
#include <array>
#include <atomic>
#include <cstdint>
#include <cstring>
#include <deque>
#include <functional>
#include <memory>
#include <string>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>
#include <vector>
#undef Yield // b/127920555
namespace vk {
class Device;
class PipelineLayout;
class ImageView;
class Sampler;
class RenderPass;
struct SampledImageDescriptor;
struct SamplerState;
namespace dbg {
class Context;
} // namespace dbg
} // namespace vk
namespace sw {
// Forward declarations.
class SpirvRoutine;
// Incrementally constructed complex bundle of rvalues
// Effectively a restricted vector, supporting only:
// - allocation to a (runtime-known) fixed component count
// - in-place construction of elements
// - const operator[]
class Intermediate
Intermediate(uint32_t componentCount)
: componentCount(componentCount)
, scalar(new rr::Value *[componentCount])
for(auto i = 0u; i < componentCount; i++) { scalar[i] = nullptr; }
delete[] scalar;
// TypeHint is used as a hint for rr::PrintValue::Ty<sw::Intermediate> to
// decide the format used to print the intermediate data.
enum class TypeHint
void move(uint32_t i, RValue<SIMD::Float> &&scalar) { emplace(i, scalar.value(), TypeHint::Float); }
void move(uint32_t i, RValue<SIMD::Int> &&scalar) { emplace(i, scalar.value(), TypeHint::Int); }
void move(uint32_t i, RValue<SIMD::UInt> &&scalar) { emplace(i, scalar.value(), TypeHint::UInt); }
void move(uint32_t i, const RValue<SIMD::Float> &scalar) { emplace(i, scalar.value(), TypeHint::Float); }
void move(uint32_t i, const RValue<SIMD::Int> &scalar) { emplace(i, scalar.value(), TypeHint::Int); }
void move(uint32_t i, const RValue<SIMD::UInt> &scalar) { emplace(i, scalar.value(), TypeHint::UInt); }
// Value retrieval functions.
RValue<SIMD::Float> Float(uint32_t i) const
ASSERT(i < componentCount);
ASSERT(scalar[i] != nullptr);
return As<SIMD::Float>(scalar[i]); // TODO(b/128539387): RValue<SIMD::Float>(scalar)
RValue<SIMD::Int> Int(uint32_t i) const
ASSERT(i < componentCount);
ASSERT(scalar[i] != nullptr);
return As<SIMD::Int>(scalar[i]); // TODO(b/128539387): RValue<SIMD::Int>(scalar)
RValue<SIMD::UInt> UInt(uint32_t i) const
ASSERT(i < componentCount);
ASSERT(scalar[i] != nullptr);
return As<SIMD::UInt>(scalar[i]); // TODO(b/128539387): RValue<SIMD::UInt>(scalar)
// No copy/move construction or assignment
Intermediate(Intermediate const &) = delete;
Intermediate(Intermediate &&) = delete;
Intermediate &operator=(Intermediate const &) = delete;
Intermediate &operator=(Intermediate &&) = delete;
const uint32_t componentCount;
void emplace(uint32_t i, rr::Value *value, TypeHint type)
ASSERT(i < componentCount);
ASSERT(scalar[i] == nullptr);
scalar[i] = value;
RR_PRINT_ONLY(typeHint = type;)
rr::Value **const scalar;
friend struct rr::PrintValue::Ty<sw::Intermediate>;
TypeHint typeHint = TypeHint::Float;
class SpirvShader
SpirvBinary insns;
using ImageSampler = void(void *texture, void *uvsIn, void *texelOut, void *constants);
enum class YieldResult
class Type;
class Object;
// Pseudo-iterator over SPIRV instructions, designed to support range-based-for.
class InsnIterator
InsnIterator(InsnIterator const &other) = default;
InsnIterator() = default;
explicit InsnIterator(SpirvBinary::const_iterator iter)
: iter{ iter }
spv::Op opcode() const
return static_cast<spv::Op>(*iter & spv::OpCodeMask);
uint32_t wordCount() const
return *iter >> spv::WordCountShift;
uint32_t word(uint32_t n) const
ASSERT(n < wordCount());
return iter[n];
uint32_t const *wordPointer(uint32_t n) const
return &iter[n];
const char *string(uint32_t n) const
return reinterpret_cast<const char *>(wordPointer(n));
// Returns the number of whole-words that a string literal starting at
// word n consumes. If the end of the intruction is reached before the
// null-terminator is found, then the function DABORT()s and 0 is
// returned.
uint32_t stringSizeInWords(uint32_t n) const
uint32_t c = wordCount();
for(uint32_t i = n; n < c; i++)
auto *u32 = wordPointer(i);
auto *u8 = reinterpret_cast<const uint8_t *>(u32);
// SPIR-V spec 2.2.1. Instructions:
// A string is interpreted as a nul-terminated stream of
// characters. The character set is Unicode in the UTF-8
// encoding scheme. The UTF-8 octets (8-bit bytes) are packed
// four per word, following the little-endian convention (i.e.,
// the first octet is in the lowest-order 8 bits of the word).
// The final word contains the string’s nul-termination
// character (0), and all contents past the end of the string in
// the final word are padded with 0.
if(u8[3] == 0)
return 1 + i - n;
DABORT("SPIR-V string literal was not null-terminated");
return 0;
bool hasResultAndType() const
bool hasResult = false, hasResultType = false;
spv::HasResultAndType(opcode(), &hasResult, &hasResultType);
return hasResultType;
SpirvID<Type> resultTypeId() const
return word(1);
SpirvID<Object> resultId() const
return word(2);
uint32_t distanceFrom(const InsnIterator &other) const
return static_cast<uint32_t>(iter - other.iter);
bool operator==(InsnIterator const &other) const
return iter == other.iter;
bool operator!=(InsnIterator const &other) const
return iter != other.iter;
InsnIterator operator*() const
return *this;
InsnIterator &operator++()
iter += wordCount();
return *this;
InsnIterator const operator++(int)
InsnIterator ret{ *this };
iter += wordCount();
return ret;
SpirvBinary::const_iterator iter;
// Range-based-for interface
InsnIterator begin() const
// Skip over the header words
return InsnIterator{ insns.cbegin() + 5 };
InsnIterator end() const
return InsnIterator{ insns.cend() };
class Type
using ID = SpirvID<Type>;
spv::Op opcode() const { return definition.opcode(); }
InsnIterator definition;
spv::StorageClass storageClass = static_cast<spv::StorageClass>(-1);
uint32_t componentCount = 0;
bool isBuiltInBlock = false;
// Inner element type for pointers, arrays, vectors and matrices.
ID element;
class Object
using ID = SpirvID<Object>;
spv::Op opcode() const { return definition.opcode(); }
Type::ID typeId() const { return definition.resultTypeId(); }
Object::ID id() const { return definition.resultId(); }
bool isConstantZero() const;
InsnIterator definition;
std::vector<uint32_t> constantValue;
enum class Kind
// Invalid default kind.
// If we get left with an object in this state, the module was
// broken.
// TODO: Better document this kind.
// A shader interface variable pointer.
// Pointer with uniform address across all lanes.
// Pointer held by SpirvRoutine::pointers
// Constant value held by Object::constantValue.
// Value held by SpirvRoutine::intermediates.
// Pointer held by SpirvRoutine::pointers
// A pointer to a vk::DescriptorSet*.
// Pointer held by SpirvRoutine::pointers.
Kind kind = Kind::Unknown;
// Block is an interval of SPIR-V instructions, starting with the
// opening OpLabel, and ending with a termination instruction.
class Block
using ID = SpirvID<Block>;
using Set = std::unordered_set<ID>;
// Edge represents the graph edge between two blocks.
struct Edge
ID from;
ID to;
bool operator==(const Edge &other) const { return from == other.from && to ==; }
struct Hash
std::size_t operator()(const Edge &edge) const noexcept
return std::hash<uint32_t>()(edge.from.value() * 31 +;
Block() = default;
Block(const Block &other) = default;
explicit Block(InsnIterator begin, InsnIterator end);
/* range-based-for interface */
inline InsnIterator begin() const { return begin_; }
inline InsnIterator end() const { return end_; }
enum Kind
Simple, // OpBranch or other simple terminator.
StructuredBranchConditional, // OpSelectionMerge + OpBranchConditional
UnstructuredBranchConditional, // OpBranchConditional
StructuredSwitch, // OpSelectionMerge + OpSwitch
UnstructuredSwitch, // OpSwitch
Loop, // OpLoopMerge + [OpBranchConditional | OpBranch]
Kind kind = Simple;
InsnIterator mergeInstruction; // Structured control flow merge instruction.
InsnIterator branchInstruction; // Branch instruction.
ID mergeBlock; // Structured flow merge block.
ID continueTarget; // Loop continue block.
Set ins; // Blocks that branch into this block.
Set outs; // Blocks that this block branches to.
bool isLoopMerge = false;
InsnIterator begin_;
InsnIterator end_;
class Function
using ID = SpirvID<Function>;
// Walks all reachable the blocks starting from id adding them to
// reachable.
void TraverseReachableBlocks(Block::ID id, Block::Set &reachable) const;
// AssignBlockFields() performs the following for all reachable blocks:
// * Assigns Block::ins with the identifiers of all blocks that contain
// this block in their Block::outs.
// * Sets Block::isLoopMerge to true if the block is the merge of a
// another loop block.
void AssignBlockFields();
// ForeachBlockDependency calls f with each dependency of the given
// block. A dependency is an incoming block that is not a loop-back
// edge.
void ForeachBlockDependency(Block::ID blockId, std::function<void(Block::ID)> f) const;
// ExistsPath returns true if there's a direct or indirect flow from
// the 'from' block to the 'to' block that does not pass through
// notPassingThrough.
bool ExistsPath(Block::ID from, Block::ID to, Block::ID notPassingThrough) const;
Block const &getBlock(Block::ID id) const
auto it = blocks.find(id);
ASSERT_MSG(it != blocks.end(), "Unknown block %d", id.value());
return it->second;
Block::ID entry; // function entry point block.
HandleMap<Block> blocks; // blocks belonging to this function.
Type::ID type; // type of the function.
Type::ID result; // return type.
using String = std::string;
using StringID = SpirvID<std::string>;
class Extension
using ID = SpirvID<Extension>;
enum Name
Name name;
struct TypeOrObject
// TypeOrObjectID is an identifier that represents a Type or an Object,
// and supports implicit casting to and from Type::ID or Object::ID.
class TypeOrObjectID : public SpirvID<TypeOrObject>
using Hash = std::hash<SpirvID<TypeOrObject>>;
inline TypeOrObjectID(uint32_t id)
: SpirvID(id)
inline TypeOrObjectID(Type::ID id)
: SpirvID(id.value())
inline TypeOrObjectID(Object::ID id)
: SpirvID(id.value())
inline operator Type::ID() const { return Type::ID(value()); }
inline operator Object::ID() const { return Object::ID(value()); }
// OpImageSample variants
enum Variant : uint32_t
None, // No Dref or Proj. Also used by OpImageFetch and OpImageQueryLod.
// Compact representation of image instruction state that is passed to the
// trampoline function for retrieving/generating the corresponding sampling routine.
struct ImageInstructionSignature
ImageInstructionSignature(Variant variant, SamplerMethod samplerMethod)
this->variant = variant;
this->samplerMethod = samplerMethod;
// Unmarshal from raw 32-bit data
explicit ImageInstructionSignature(uint32_t signature)
: signature(signature)
SamplerFunction getSamplerFunction() const
return { samplerMethod, offset != 0, sample != 0 };
bool isDref() const
return (variant == Dref) || (variant == ProjDref);
bool isProj() const
return (variant == Proj) || (variant == ProjDref);
bool hasLod() const
return samplerMethod == Lod || samplerMethod == Fetch; // We always pass a Lod operand for Fetch operations.
bool hasGrad() const
return samplerMethod == Grad;
Variant variant : BITS(VARIANT_LAST);
SamplerMethod samplerMethod : BITS(SAMPLER_METHOD_LAST);
uint32_t gatherComponent : 2;
uint32_t dim : BITS(spv::DimSubpassData); // spv::Dim
uint32_t arrayed : 1;
uint32_t imageFormat : BITS(spv::ImageFormatR64i); // spv::ImageFormat
// Parameters are passed to the sampling routine in this order:
uint32_t coordinates : 3; // 1-4 (does not contain projection component)
/* uint32_t dref : 1; */ // Indicated by Variant::ProjDref|Dref
/* uint32_t lodOrBias : 1; */ // Indicated by SamplerMethod::Lod|Bias|Fetch
uint32_t grad : 2; // 0-3 components (for each of dx / dy)
uint32_t offset : 2; // 0-3 components
uint32_t sample : 1; // 0-1 scalar integer
uint32_t signature = 0;
// This gets stored as a literal in the generated code, so it should be compact.
static_assert(sizeof(ImageInstructionSignature) == sizeof(uint32_t), "ImageInstructionSignature must be 32-bit");
struct ImageInstruction : public ImageInstructionSignature
ImageInstruction(InsnIterator insn, const SpirvShader &spirv);
const uint32_t position;
Type::ID resultTypeId = 0;
Object::ID resultId = 0;
Object::ID imageId = 0;
Object::ID samplerId = 0;
Object::ID coordinateId = 0;
Object::ID texelId = 0;
Object::ID drefId = 0;
Object::ID lodOrBiasId = 0;
Object::ID gradDxId = 0;
Object::ID gradDyId = 0;
Object::ID offsetId = 0;
Object::ID sampleId = 0;
static ImageInstructionSignature parseVariantAndMethod(InsnIterator insn);
static uint32_t getImageOperandsIndex(InsnIterator insn);
static uint32_t getImageOperandsMask(InsnIterator insn);
// This method is for retrieving an ID that uniquely identifies the
// shader entry point represented by this object.
uint64_t getIdentifier() const
return ((uint64_t)entryPoint.value() << 32) | insns.getIdentifier();
SpirvShader(VkShaderStageFlagBits stage,
const char *entryPointName,
SpirvBinary const &insns,
const vk::RenderPass *renderPass,
uint32_t subpassIndex,
bool robustBufferAccess,
const std::shared_ptr<vk::dbg::Context> &dbgctx);
struct ExecutionModes
bool EarlyFragmentTests : 1;
bool DepthReplacing : 1;
bool DepthGreater : 1;
bool DepthLess : 1;
bool DepthUnchanged : 1;
// Compute workgroup dimensions
int WorkgroupSizeX = 1;
int WorkgroupSizeY = 1;
int WorkgroupSizeZ = 1;
const ExecutionModes &getExecutionModes() const
return executionModes;
struct Analysis
bool ContainsKill : 1;
bool ContainsControlBarriers : 1;
bool NeedsCentroid : 1;
bool ContainsSampleQualifier : 1;
const Analysis &getAnalysis() const
return analysis;
struct Capabilities
bool Matrix : 1;
bool Shader : 1;
bool StorageImageMultisample : 1;
bool ClipDistance : 1;
bool CullDistance : 1;
bool ImageCubeArray : 1;
bool SampleRateShading : 1;
bool InputAttachment : 1;
bool Sampled1D : 1;
bool Image1D : 1;
bool SampledBuffer : 1;
bool SampledCubeArray : 1;
bool ImageBuffer : 1;
bool ImageMSArray : 1;
bool StorageImageExtendedFormats : 1;
bool ImageQuery : 1;
bool DerivativeControl : 1;
bool InterpolationFunction : 1;
bool StorageImageWriteWithoutFormat : 1;
bool GroupNonUniform : 1;
bool GroupNonUniformVote : 1;
bool GroupNonUniformBallot : 1;
bool GroupNonUniformShuffle : 1;
bool GroupNonUniformShuffleRelative : 1;
bool GroupNonUniformArithmetic : 1;
bool DeviceGroup : 1;
bool MultiView : 1;
bool StencilExportEXT : 1;
bool VulkanMemoryModel : 1;
bool VulkanMemoryModelDeviceScope : 1;
const Capabilities &getUsedCapabilities() const
return capabilities;
// getNumOutputClipDistances() returns the number of ClipDistances
// outputted by this shader.
unsigned int getNumOutputClipDistances() const
auto it = outputBuiltins.find(spv::BuiltInClipDistance);
if(it != outputBuiltins.end())
return it->second.SizeInComponents;
return 0;
// getNumOutputCullDistances() returns the number of CullDistances
// outputted by this shader.
unsigned int getNumOutputCullDistances() const
auto it = outputBuiltins.find(spv::BuiltInCullDistance);
if(it != outputBuiltins.end())
return it->second.SizeInComponents;
return 0;
enum AttribType : unsigned char
bool hasBuiltinInput(spv::BuiltIn b) const
return inputBuiltins.find(b) != inputBuiltins.end();
bool hasBuiltinOutput(spv::BuiltIn b) const
return outputBuiltins.find(b) != outputBuiltins.end();
struct Decorations
int32_t Location = -1;
int32_t Component = 0;
spv::BuiltIn BuiltIn = static_cast<spv::BuiltIn>(-1);
int32_t Offset = -1;
int32_t ArrayStride = -1;
int32_t MatrixStride = 1;
bool HasLocation : 1;
bool HasComponent : 1;
bool HasBuiltIn : 1;
bool HasOffset : 1;
bool HasArrayStride : 1;
bool HasMatrixStride : 1;
bool HasRowMajor : 1; // whether RowMajor bit is valid.
bool Flat : 1;
bool Centroid : 1;
bool NoPerspective : 1;
bool Block : 1;
bool BufferBlock : 1;
bool RelaxedPrecision : 1;
bool RowMajor : 1; // RowMajor if true; ColMajor if false
bool InsideMatrix : 1; // pseudo-decoration for whether we're inside a matrix.
: Location{ -1 }
, Component{ 0 }
, BuiltIn{ static_cast<spv::BuiltIn>(-1) }
, Offset{ -1 }
, ArrayStride{ -1 }
, MatrixStride{ -1 }
, HasLocation{ false }
, HasComponent{ false }
, HasBuiltIn{ false }
, HasOffset{ false }
, HasArrayStride{ false }
, HasMatrixStride{ false }
, HasRowMajor{ false }
, Flat{ false }
, Centroid{ false }
, NoPerspective{ false }
, Block{ false }
, BufferBlock{ false }
, RelaxedPrecision{ false }
, RowMajor{ false }
, InsideMatrix{ false }
Decorations(Decorations const &) = default;
void Apply(Decorations const &src);
void Apply(spv::Decoration decoration, uint32_t arg);
std::unordered_map<TypeOrObjectID, Decorations, TypeOrObjectID::Hash> decorations;
std::unordered_map<Type::ID, std::vector<Decorations>> memberDecorations;
struct DescriptorDecorations
int32_t DescriptorSet = -1;
int32_t Binding = -1;
int32_t InputAttachmentIndex = -1;
void Apply(DescriptorDecorations const &src);
std::unordered_map<Object::ID, DescriptorDecorations> descriptorDecorations;
std::vector<vk::Format> inputAttachmentFormats;
struct InterfaceComponent
AttribType Type;
bool Flat : 1;
bool Centroid : 1;
bool NoPerspective : 1;
uint8_t DecorationBits;
, DecorationBits{ 0 }
struct BuiltinMapping
Object::ID Id;
uint32_t FirstComponent;
uint32_t SizeInComponents;
struct WorkgroupMemory
// allocates a new variable of size bytes with the given identifier.
inline void allocate(Object::ID id, uint32_t size)
uint32_t offset = totalSize;
auto it = offsets.emplace(id, offset);
ASSERT_MSG(it.second, "WorkgroupMemory already has an allocation for object %d", int(id.value()));
totalSize += size;
// returns the byte offset of the variable with the given identifier.
inline uint32_t offsetOf(Object::ID id) const
auto it = offsets.find(id);
ASSERT_MSG(it != offsets.end(), "WorkgroupMemory has no allocation for object %d", int(id.value()));
return it->second;
// returns the total allocated size in bytes.
inline uint32_t size() const { return totalSize; }
uint32_t totalSize = 0; // in bytes
std::unordered_map<Object::ID, uint32_t> offsets; // in bytes
std::vector<InterfaceComponent> inputs;
std::vector<InterfaceComponent> outputs;
void emitProlog(SpirvRoutine *routine) const;
void emit(SpirvRoutine *routine, RValue<SIMD::Int> const &activeLaneMask, RValue<SIMD::Int> const &storesAndAtomicsMask, const vk::DescriptorSet::Bindings &descriptorSets, unsigned int multiSampleCount = 0) const;
void emitEpilog(SpirvRoutine *routine) const;
void clearPhis(SpirvRoutine *routine) const;
bool containsImageWrite() const { return imageWriteEmitted; }
using BuiltInHash = std::hash<std::underlying_type<spv::BuiltIn>::type>;
std::unordered_map<spv::BuiltIn, BuiltinMapping, BuiltInHash> inputBuiltins;
std::unordered_map<spv::BuiltIn, BuiltinMapping, BuiltInHash> outputBuiltins;
WorkgroupMemory workgroupMemory;
const bool robustBufferAccess;
Function::ID entryPoint;
spv::ExecutionModel executionModel = spv::ExecutionModelMax; // Invalid prior to OpEntryPoint parsing.
ExecutionModes executionModes = {};
Capabilities capabilities = {};
spv::AddressingModel addressingModel = spv::AddressingModelLogical;
spv::MemoryModel memoryModel = spv::MemoryModelSimple;
HandleMap<Extension> extensionsByID;
std::unordered_set<uint32_t> extensionsImported;
Analysis analysis = {};
mutable bool imageWriteEmitted = false;
HandleMap<Type> types;
HandleMap<Object> defs;
HandleMap<Function> functions;
std::unordered_map<StringID, String> strings;
// DeclareType creates a Type for the given OpTypeX instruction, storing
// it into the types map. It is called from the analysis pass (constructor).
void DeclareType(InsnIterator insn);
void ProcessExecutionMode(InsnIterator it);
uint32_t ComputeTypeSize(InsnIterator insn);
void ApplyDecorationsForId(Decorations *d, TypeOrObjectID id) const;
void ApplyDecorationsForIdMember(Decorations *d, Type::ID id, uint32_t member) const;
void ApplyDecorationsForAccessChain(Decorations *d, DescriptorDecorations *dd, Object::ID baseId, uint32_t numIndexes, uint32_t const *indexIds) const;
// Creates an Object for the instruction's result in 'defs'.
void DefineResult(const InsnIterator &insn);
// Processes the OpenCL.Debug.100 instruction for the initial definition
// pass of the SPIR-V.
void DefineOpenCLDebugInfo100(const InsnIterator &insn);
// Returns true if data in the given storage class is word-interleaved
// by each SIMD vector lane, otherwise data is stored linerally.
// Each lane addresses a single word, picked by a base pointer and an
// integer offset.
// A word is currently 32 bits (single float, int32_t, uint32_t).
// A lane is a single element of a SIMD vector register.
// Storage interleaved by lane - (IsStorageInterleavedByLane() == true):
// ---------------------------------------------------------------------
// Address = PtrBase + sizeof(Word) * (SIMD::Width * LaneOffset + LaneIndex)
// Assuming SIMD::Width == 4:
// Lane[0] | Lane[1] | Lane[2] | Lane[3]
// ===========+===========+===========+==========
// LaneOffset=0: | Word[0] | Word[1] | Word[2] | Word[3]
// ---------------+-----------+-----------+-----------+----------
// LaneOffset=1: | Word[4] | Word[5] | Word[6] | Word[7]
// ---------------+-----------+-----------+-----------+----------
// LaneOffset=2: | Word[8] | Word[9] | Word[a] | Word[b]
// ---------------+-----------+-----------+-----------+----------
// LaneOffset=3: | Word[c] | Word[d] | Word[e] | Word[f]
// Linear storage - (IsStorageInterleavedByLane() == false):
// ---------------------------------------------------------
// Address = PtrBase + sizeof(Word) * LaneOffset
// Lane[0] | Lane[1] | Lane[2] | Lane[3]
// ===========+===========+===========+==========
// LaneOffset=0: | Word[0] | Word[0] | Word[0] | Word[0]
// ---------------+-----------+-----------+-----------+----------
// LaneOffset=1: | Word[1] | Word[1] | Word[1] | Word[1]
// ---------------+-----------+-----------+-----------+----------
// LaneOffset=2: | Word[2] | Word[2] | Word[2] | Word[2]
// ---------------+-----------+-----------+-----------+----------
// LaneOffset=3: | Word[3] | Word[3] | Word[3] | Word[3]
static bool IsStorageInterleavedByLane(spv::StorageClass storageClass);
static bool IsExplicitLayout(spv::StorageClass storageClass);
static sw::SIMD::Pointer InterleaveByLane(sw::SIMD::Pointer p);
// Output storage buffers and images should not be affected by helper invocations
static bool StoresInHelperInvocation(spv::StorageClass storageClass);
using InterfaceVisitor = std::function<void(Decorations const, AttribType)>;
void VisitInterface(Object::ID id, const InterfaceVisitor &v) const;
int VisitInterfaceInner(Type::ID id, Decorations d, const InterfaceVisitor &v) const;
// MemoryElement describes a scalar element within a structure, and is
// used by the callback function of VisitMemoryObject().
struct MemoryElement
uint32_t index; // index of the scalar element
uint32_t offset; // offset (in bytes) from the base of the object
const Type &type; // element type
using MemoryVisitor = std::function<void(const MemoryElement &)>;
// VisitMemoryObject() walks a type tree in an explicitly laid out
// storage class, calling the MemoryVisitor for each scalar element
// within the
void VisitMemoryObject(Object::ID id, const MemoryVisitor &v) const;
// VisitMemoryObjectInner() is internally called by VisitMemoryObject()
void VisitMemoryObjectInner(Type::ID id, Decorations d, uint32_t &index, uint32_t offset, const MemoryVisitor &v) const;
Object &CreateConstant(InsnIterator it);
void ProcessInterfaceVariable(Object &object);
// EmitState holds control-flow state for the emit() pass.
class EmitState
EmitState(SpirvRoutine *routine,
Function::ID function,
RValue<SIMD::Int> activeLaneMask,
RValue<SIMD::Int> storesAndAtomicsMask,
const vk::DescriptorSet::Bindings &descriptorSets,
bool robustBufferAccess,
unsigned int multiSampleCount,
spv::ExecutionModel executionModel)
: routine(routine)
, function(function)
, activeLaneMaskValue(activeLaneMask.value())
, storesAndAtomicsMaskValue(storesAndAtomicsMask.value())
, descriptorSets(descriptorSets)
, robustBufferAccess(robustBufferAccess)
, multiSampleCount(multiSampleCount)
, executionModel(executionModel)
ASSERT(executionModel != spv::ExecutionModelMax); // Must parse OpEntryPoint before emitting.
// Returns the mask describing the active lanes as updated by dynamic
// control flow. Active lanes include helper invocations, used for
// calculating fragment derivitives, which must not perform memory
// stores or atomic writes.
// Use activeStoresAndAtomicsMask() to consider both control flow and
// lanes which are permitted to perform memory stores and atomic
// operations
RValue<SIMD::Int> activeLaneMask() const
ASSERT(activeLaneMaskValue != nullptr);
return RValue<SIMD::Int>(activeLaneMaskValue);
// Returns the immutable lane mask that describes which lanes are
// permitted to perform memory stores and atomic operations.
// Note that unlike activeStoresAndAtomicsMask() this mask *does not*
// consider lanes that have been made inactive due to control flow.
RValue<SIMD::Int> storesAndAtomicsMask() const
ASSERT(storesAndAtomicsMaskValue != nullptr);
return RValue<SIMD::Int>(storesAndAtomicsMaskValue);
// Returns a lane mask that describes which lanes are permitted to
// perform memory stores and atomic operations, considering lanes that
// may have been made inactive due to control flow.
RValue<SIMD::Int> activeStoresAndAtomicsMask() const
return activeLaneMask() & storesAndAtomicsMask();
// Add a new active lane mask edge from the current block to out.
// The edge mask value will be (mask AND activeLaneMaskValue).
// If multiple active lane masks are added for the same edge, then
// they will be ORed together.
void addOutputActiveLaneMaskEdge(Block::ID out, RValue<SIMD::Int> mask);
// Add a new active lane mask for the edge from -> to.
// If multiple active lane masks are added for the same edge, then
// they will be ORed together.
void addActiveLaneMaskEdge(Block::ID from, Block::ID to, RValue<SIMD::Int> mask);
SpirvRoutine *routine = nullptr; // The current routine being built.
Function::ID function; // The current function being built.
Block::ID block; // The current block being built.
rr::Value *activeLaneMaskValue = nullptr; // The current active lane mask.
rr::Value *storesAndAtomicsMaskValue = nullptr; // The current atomics mask.
Block::Set visited; // Blocks already built.
std::unordered_map<Block::Edge, RValue<SIMD::Int>, Block::Edge::Hash> edgeActiveLaneMasks;
std::deque<Block::ID> *pending;
const vk::DescriptorSet::Bindings &descriptorSets;
OutOfBoundsBehavior getOutOfBoundsBehavior(spv::StorageClass storageClass) const;
unsigned int getMultiSampleCount() const { return multiSampleCount; }
Intermediate &createIntermediate(Object::ID id, uint32_t componentCount)
auto it = intermediates.emplace(std::piecewise_construct,
ASSERT_MSG(it.second, "Intermediate %d created twice", id.value());
return it.first->second;
Intermediate const &getIntermediate(Object::ID id) const
auto it = intermediates.find(id);
ASSERT_MSG(it != intermediates.end(), "Unknown intermediate %d", id.value());
return it->second;
void createPointer(Object::ID id, SIMD::Pointer ptr)
bool added = pointers.emplace(id, ptr).second;
ASSERT_MSG(added, "Pointer %d created twice", id.value());
SIMD::Pointer const &getPointer(Object::ID id) const
auto it = pointers.find(id);
ASSERT_MSG(it != pointers.end(), "Unknown pointer %d", id.value());
return it->second;
std::unordered_map<Object::ID, Intermediate> intermediates;
std::unordered_map<Object::ID, SIMD::Pointer> pointers;
const bool robustBufferAccess; // Emit robustBufferAccess safe code.
const unsigned int multiSampleCount;
const spv::ExecutionModel executionModel;
// EmitResult is an enumerator of result values from the Emit functions.
enum class EmitResult
Continue, // No termination instructions.
Terminator, // Reached a termination instruction.
// Generic wrapper over either per-lane intermediate value, or a constant.
// Constants are transparently widened to per-lane values in operator[].
// This is appropriate in most cases -- if we're not going to do something
// significantly different based on whether the value is uniform across lanes.
class Operand
Operand(const SpirvShader *shader, const EmitState *state, SpirvShader::Object::ID objectId);
Operand(const Intermediate &value);
RValue<SIMD::Float> Float(uint32_t i) const
return intermediate->Float(i);
// Constructing a constant SIMD::Float is not guaranteed to preserve the data's exact
// bit pattern, but SPIR-V provides 32-bit words representing "the bit pattern for the constant".
// Thus we must first construct an integer constant, and bitcast to float.
return As<SIMD::Float>(SIMD::UInt(constant[i]));
RValue<SIMD::Int> Int(uint32_t i) const
return intermediate->Int(i);
return SIMD::Int(constant[i]);
RValue<SIMD::UInt> UInt(uint32_t i) const
return intermediate->UInt(i);
return SIMD::UInt(constant[i]);
RR_PRINT_ONLY(friend struct rr::PrintValue::Ty<Operand>;)
// Delegate constructor
Operand(const EmitState *state, const Object &object);
const uint32_t *constant;
const Intermediate *intermediate;
const uint32_t componentCount;
RR_PRINT_ONLY(friend struct rr::PrintValue::Ty<Operand>;)
Type const &getType(Type::ID id) const
auto it = types.find(id);
ASSERT_MSG(it != types.end(), "Unknown type %d", id.value());
return it->second;
Type const &getType(const Object &object) const
return getType(object.typeId());
Object const &getObject(Object::ID id) const
auto it = defs.find(id);
ASSERT_MSG(it != defs.end(), "Unknown object %d", id.value());
return it->second;
Type const &getObjectType(Object::ID id) const
return getType(getObject(id));
Function const &getFunction(Function::ID id) const
auto it = functions.find(id);
ASSERT_MSG(it != functions.end(), "Unknown function %d", id.value());
return it->second;
String const &getString(StringID id) const
auto it = strings.find(id);
ASSERT_MSG(it != strings.end(), "Unknown string %d", id.value());
return it->second;
Extension const &getExtension(Extension::ID id) const
auto it = extensionsByID.find(id);
ASSERT_MSG(it != extensionsByID.end(), "Unknown extension %d", id.value());
return it->second;
// Returns a SIMD::Pointer to the underlying data for the given pointer
// object.
// Handles objects of the following kinds:
// - DescriptorSet
// - Pointer
// - InterfaceVariable
// Calling GetPointerToData with objects of any other kind will assert.
SIMD::Pointer GetPointerToData(Object::ID id, Int arrayIndex, EmitState const *state) const;
SIMD::Pointer WalkExplicitLayoutAccessChain(Object::ID id, uint32_t numIndexes, uint32_t const *indexIds, EmitState const *state) const;
SIMD::Pointer WalkAccessChain(Object::ID id, uint32_t numIndexes, uint32_t const *indexIds, EmitState const *state) const;
// Returns the *component* offset in the literal for the given access chain.
uint32_t WalkLiteralAccessChain(Type::ID id, uint32_t numIndexes, uint32_t const *indexes) const;
// Lookup the active lane mask for the edge from -> to.
// If from is unreachable, then a mask of all zeros is returned.
// Asserts if from is reachable and the edge does not exist.
RValue<SIMD::Int> GetActiveLaneMaskEdge(EmitState *state, Block::ID from, Block::ID to) const;
// Updates the current active lane mask.
void SetActiveLaneMask(RValue<SIMD::Int> mask, EmitState *state) const;
// Emit all the unvisited blocks (except for ignore) in DFS order,
// starting with id.
void EmitBlocks(Block::ID id, EmitState *state, Block::ID ignore = 0) const;
void EmitNonLoop(EmitState *state) const;
void EmitLoop(EmitState *state) const;
void EmitInstructions(InsnIterator begin, InsnIterator end, EmitState *state) const;
EmitResult EmitInstruction(InsnIterator insn, EmitState *state) const;
// Emit pass instructions:
EmitResult EmitVariable(InsnIterator insn, EmitState *state) const;
EmitResult EmitLoad(InsnIterator insn, EmitState *state) const;
EmitResult EmitStore(InsnIterator insn, EmitState *state) const;
EmitResult EmitAccessChain(InsnIterator insn, EmitState *state) const;
EmitResult EmitCompositeConstruct(InsnIterator insn, EmitState *state) const;
EmitResult EmitCompositeInsert(InsnIterator insn, EmitState *state) const;
EmitResult EmitCompositeExtract(InsnIterator insn, EmitState *state) const;
EmitResult EmitVectorShuffle(InsnIterator insn, EmitState *state) const;
EmitResult EmitVectorTimesScalar(InsnIterator insn, EmitState *state) const;
EmitResult EmitMatrixTimesVector(InsnIterator insn, EmitState *state) const;
EmitResult EmitVectorTimesMatrix(InsnIterator insn, EmitState *state) const;
EmitResult EmitMatrixTimesMatrix(InsnIterator insn, EmitState *state) const;
EmitResult EmitOuterProduct(InsnIterator insn, EmitState *state) const;
EmitResult EmitTranspose(InsnIterator insn, EmitState *state) const;
EmitResult EmitVectorExtractDynamic(InsnIterator insn, EmitState *state) const;
EmitResult EmitVectorInsertDynamic(InsnIterator insn, EmitState *state) const;
EmitResult EmitUnaryOp(InsnIterator insn, EmitState *state) const;
EmitResult EmitBinaryOp(InsnIterator insn, EmitState *state) const;
EmitResult EmitDot(InsnIterator insn, EmitState *state) const;
EmitResult EmitSelect(InsnIterator insn, EmitState *state) const;
EmitResult EmitExtendedInstruction(InsnIterator insn, EmitState *state) const;
EmitResult EmitExtGLSLstd450(InsnIterator insn, EmitState *state) const;
EmitResult EmitOpenCLDebugInfo100(InsnIterator insn, EmitState *state) const;
EmitResult EmitLine(InsnIterator insn, EmitState *state) const;
EmitResult EmitAny(InsnIterator insn, EmitState *state) const;
EmitResult EmitAll(InsnIterator insn, EmitState *state) const;
EmitResult EmitBranch(InsnIterator insn, EmitState *state) const;
EmitResult EmitBranchConditional(InsnIterator insn, EmitState *state) const;
EmitResult EmitSwitch(InsnIterator insn, EmitState *state) const;
EmitResult EmitUnreachable(InsnIterator insn, EmitState *state) const;
EmitResult EmitReturn(InsnIterator insn, EmitState *state) const;
EmitResult EmitKill(InsnIterator insn, EmitState *state) const;
EmitResult EmitFunctionCall(InsnIterator insn, EmitState *state) const;
EmitResult EmitPhi(InsnIterator insn, EmitState *state) const;
EmitResult EmitImageSample(const ImageInstruction &instruction, EmitState *state) const;
EmitResult EmitImageQuerySizeLod(InsnIterator insn, EmitState *state) const;
EmitResult EmitImageQuerySize(InsnIterator insn, EmitState *state) const;
EmitResult EmitImageQueryLevels(InsnIterator insn, EmitState *state) const;
EmitResult EmitImageQuerySamples(InsnIterator insn, EmitState *state) const;
EmitResult EmitImageRead(const ImageInstruction &instruction, EmitState *state) const;
EmitResult EmitImageWrite(const ImageInstruction &instruction, EmitState *state) const;
EmitResult EmitImageTexelPointer(const ImageInstruction &instruction, EmitState *state) const;
EmitResult EmitAtomicOp(InsnIterator insn, EmitState *state) const;
EmitResult EmitAtomicCompareExchange(InsnIterator insn, EmitState *state) const;
EmitResult EmitSampledImageCombineOrSplit(InsnIterator insn, EmitState *state) const;
EmitResult EmitCopyObject(InsnIterator insn, EmitState *state) const;
EmitResult EmitCopyMemory(InsnIterator insn, EmitState *state) const;
EmitResult EmitControlBarrier(InsnIterator insn, EmitState *state) const;
EmitResult EmitMemoryBarrier(InsnIterator insn, EmitState *state) const;
EmitResult EmitGroupNonUniform(InsnIterator insn, EmitState *state) const;
EmitResult EmitArrayLength(InsnIterator insn, EmitState *state) const;
// Emits code to sample an image, regardless of whether any SIMD lanes are active.
void EmitImageSampleUnconditional(Array<SIMD::Float> &out, const ImageInstruction &instruction, EmitState *state) const;
Pointer<Byte> lookupSamplerFunction(Pointer<Byte> imageDescriptor, const ImageInstruction &instruction, EmitState *state) const;
void callSamplerFunction(Pointer<Byte> samplerFunction, Array<SIMD::Float> &out, Pointer<Byte> imageDescriptor, const ImageInstruction &instruction, EmitState *state) const;
void GetImageDimensions(EmitState const *state, Type const &resultTy, Object::ID imageId, Object::ID lodId, Intermediate &dst) const;
static SIMD::Pointer GetTexelAddress(ImageInstructionSignature instruction, Pointer<Byte> descriptor, SIMD::Int coordinate[], SIMD::Int sample, vk::Format imageFormat, OutOfBoundsBehavior outOfBoundsBehavior, const EmitState *state);
static void WriteImage(ImageInstructionSignature instruction, Pointer<Byte> descriptor, const Pointer<SIMD::Int> &coord, const Pointer<SIMD::Int> &texelAndMask, vk::Format imageFormat);
uint32_t GetConstScalarInt(Object::ID id) const;
void EvalSpecConstantOp(InsnIterator insn);
void EvalSpecConstantUnaryOp(InsnIterator insn);
void EvalSpecConstantBinaryOp(InsnIterator insn);
// Fragment input interpolation functions
uint32_t GetNumInputComponents(int32_t location) const;
uint32_t GetPackedInterpolant(int32_t location) const;
enum InterpolationType
SIMD::Float Interpolate(SIMD::Pointer const &ptr, int32_t location, Object::ID paramId,
uint32_t component, EmitState *state, InterpolationType type) const;
// Helper for implementing OpStore, which doesn't take an InsnIterator so it
// can also store independent operands.
void Store(Object::ID pointerId, const Operand &value, bool atomic, std::memory_order memoryOrder, EmitState *state) const;
// LoadPhi loads the phi values from the alloca storage and places the
// load values into the intermediate with the phi's result id.
void LoadPhi(InsnIterator insn, EmitState *state) const;
// StorePhi updates the phi's alloca storage value using the incoming
// values from blocks that are both in the OpPhi instruction and in
// filter.
void StorePhi(Block::ID blockID, InsnIterator insn, EmitState *state, std::unordered_set<SpirvShader::Block::ID> const &filter) const;
// Emits a rr::Fence for the given MemorySemanticsMask.
void Fence(spv::MemorySemanticsMask semantics) const;
// Helper for calling rr::Yield with res cast to an rr::Int.
void Yield(YieldResult res) const;
// WriteCFGGraphVizDotFile() writes a graphviz dot file of the shader's
// control flow to the given file path.
void WriteCFGGraphVizDotFile(const char *path) const;
// OpcodeName() returns the name of the opcode op.
static const char *OpcodeName(spv::Op op);
static std::memory_order MemoryOrder(spv::MemorySemanticsMask memorySemantics);
// IsStatement() returns true if the given opcode actually performs
// work (as opposed to declaring a type, defining a function start / end,
// etc).
static bool IsStatement(spv::Op op);
// HasTypeAndResult() returns true if the given opcode's instruction
// has a result type ID and result ID, i.e. defines an Object.
static bool HasTypeAndResult(spv::Op op);
// Helper as we often need to take dot products as part of doing other things.
SIMD::Float Dot(unsigned numComponents, Operand const &x, Operand const &y) const;
// Splits x into a floating-point significand in the range [0.5, 1.0)
// and an integral exponent of two, such that:
// x = significand * 2^exponent
// Returns the pair <significand, exponent>
std::pair<SIMD::Float, SIMD::Int> Frexp(RValue<SIMD::Float> val) const;
static ImageSampler *getImageSampler(const vk::Device *device, uint32_t signature, uint32_t samplerId, uint32_t imageViewId);
static std::shared_ptr<rr::Routine> emitSamplerRoutine(ImageInstructionSignature instruction, const Sampler &samplerState);
static std::shared_ptr<rr::Routine> emitWriteRoutine(ImageInstructionSignature instruction, const Sampler &samplerState);
// TODO(b/129523279): Eliminate conversion and use vk::Sampler members directly.
static sw::FilterType convertFilterMode(const vk::SamplerState *samplerState, VkImageViewType imageViewType, SamplerMethod samplerMethod);
static sw::MipmapType convertMipmapMode(const vk::SamplerState *samplerState);
static sw::AddressingMode convertAddressingMode(int coordinateIndex, const vk::SamplerState *samplerState, VkImageViewType imageViewType);
// Returns 0 when invalid.
static VkShaderStageFlagBits executionModelToStage(spv::ExecutionModel model);
// Debugger API functions. When ENABLE_VK_DEBUGGER is not defined, these
// are all no-ops.
// dbgInit() initializes the debugger code generation.
// All other dbgXXX() functions are no-op until this is called.
void dbgInit(const std::shared_ptr<vk::dbg::Context> &dbgctx);
// dbgTerm() terminates the debugger code generation.
void dbgTerm();
// dbgCreateFile() generates a synthetic file containing the disassembly
// of the SPIR-V shader. This is the file displayed in the debug
// session.
void dbgCreateFile();
// dbgBeginEmit() sets up the debugging state for the shader.
void dbgBeginEmit(EmitState *state) const;
// dbgEndEmit() tears down the debugging state for the shader.
void dbgEndEmit(EmitState *state) const;
// dbgBeginEmitInstruction() updates the current debugger location for
// the given instruction.
void dbgBeginEmitInstruction(InsnIterator insn, EmitState *state) const;
// dbgEndEmitInstruction() creates any new debugger variables for the
// instruction that just completed.
void dbgEndEmitInstruction(InsnIterator insn, EmitState *state) const;
// dbgExposeIntermediate() exposes the intermediate with the given ID to
// the debugger.
void dbgExposeIntermediate(Object::ID id, EmitState *state) const;
// dbgUpdateActiveLaneMask() updates the active lane masks to the
// debugger.
void dbgUpdateActiveLaneMask(RValue<SIMD::Int> mask, EmitState *state) const;
// dbgDeclareResult() associates resultId as the result of the given
// instruction.
void dbgDeclareResult(const InsnIterator &insn, Object::ID resultId) const;
// Impl holds forward declaration structs and pointers to state for the
// private implementations in the corresponding SpirvShaderXXX.cpp files.
// This allows access to the private members of the SpirvShader, without
// littering the header with implementation details.
struct Impl
struct Debugger;
struct Group;
Debugger *debugger = nullptr;
Impl impl;
class SpirvRoutine
SpirvRoutine(vk::PipelineLayout const *pipelineLayout);
using Variable = Array<SIMD::Float>;
// Single-entry 'inline' sampler routine cache.
struct SamplerCache
Pointer<Byte> imageDescriptor = nullptr;
Int samplerId;
Pointer<Byte> function;
struct InterpolationData
Pointer<Byte> primitive;
SIMD::Float x;
SIMD::Float y;
SIMD::Float rhw;
SIMD::Float xCentroid;
SIMD::Float yCentroid;
SIMD::Float rhwCentroid;
vk::PipelineLayout const *const pipelineLayout;
std::unordered_map<SpirvShader::Object::ID, Variable> variables;
std::unordered_map<uint32_t, SamplerCache> samplerCache; // Indexed by the instruction position, in words.
Variable inputs = Variable{ MAX_INTERFACE_COMPONENTS };
Variable outputs = Variable{ MAX_INTERFACE_COMPONENTS };
InterpolationData interpolationData;
Pointer<Byte> device;
Pointer<Byte> workgroupMemory;
Pointer<Pointer<Byte>> descriptorSets;
Pointer<Int> descriptorDynamicOffsets;
Pointer<Byte> pushConstants;
Pointer<Byte> constants;
Int killMask = Int{ 0 };
// Shader invocation state.
// Not all of these variables are used for every type of shader, and some
// are only used when debugging. See b/146486064 for more information.
// Give careful consideration to the runtime performance loss before adding
// more state here.
std::array<SIMD::Int, 2> windowSpacePosition;
Int viewID; // slice offset into input attachments for multiview, even if the shader doesn't use ViewIndex
Int instanceID;
SIMD::Int vertexIndex;
std::array<SIMD::Float, 4> fragCoord;
std::array<SIMD::Float, 4> pointCoord;
SIMD::Int helperInvocation;
Int4 numWorkgroups;
Int4 workgroupID;
Int4 workgroupSize;
Int subgroupsPerWorkgroup;
Int invocationsPerSubgroup;
Int subgroupIndex;
SIMD::Int localInvocationIndex;
std::array<SIMD::Int, 3> localInvocationID;
std::array<SIMD::Int, 3> globalInvocationID;
Pointer<Byte> dbgState; // Pointer to a debugger state.
void createVariable(SpirvShader::Object::ID id, uint32_t componentCount)
bool added = variables.emplace(id, Variable(componentCount)).second;
ASSERT_MSG(added, "Variable %d created twice", id.value());
Variable &getVariable(SpirvShader::Object::ID id)
auto it = variables.find(id);
ASSERT_MSG(it != variables.end(), "Unknown variables %d", id.value());
return it->second;
// setImmutableInputBuiltins() sets all the immutable input builtins,
// common for all shader types.
void setImmutableInputBuiltins(SpirvShader const *shader);
static SIMD::Float interpolateAtXY(const SIMD::Float &x, const SIMD::Float &y, const SIMD::Float &rhw, Pointer<Byte> planeEquation, bool flat, bool perspective);
// setInputBuiltin() calls f() with the builtin and value if the shader
// uses the input builtin, otherwise the call is a no-op.
// F is a function with the signature:
// void(const SpirvShader::BuiltinMapping& builtin, Array<SIMD::Float>& value)
template<typename F>
inline void setInputBuiltin(SpirvShader const *shader, spv::BuiltIn id, F &&f)
auto it = shader->inputBuiltins.find(id);
if(it != shader->inputBuiltins.end())
const auto &builtin = it->second;
f(builtin, getVariable(builtin.Id));
// The phis are only accessible to SpirvShader as they are only used and
// exist between calls to SpirvShader::emitProlog() and
// SpirvShader::emitEpilog().
friend class SpirvShader;
std::unordered_map<SpirvShader::Object::ID, Variable> phis;
} // namespace sw
#endif // sw_SpirvShader_hpp