Google Git
Sign in
dawn / tint / bf0180bcee90e8624d8063e55624bfebd8f7fb76 / . / src / writer / spirv / builder.cc
blob: 932ae8c093307b0b0cff0b667da90357bd9be1ee [file] [log] [blame]
// Copyright 2020 The Tint Authors. //
// 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 "src/writer/spirv/builder.h"
#include <algorithm>
#include <limits>
#include <utility>
#include "spirv/unified1/GLSL.std.450.h"
#include "src/ast/call_statement.h"
#include "src/ast/fallthrough_statement.h"
#include "src/ast/internal_attribute.h"
#include "src/ast/override_attribute.h"
#include "src/ast/traverse_expressions.h"
#include "src/sem/array.h"
#include "src/sem/atomic_type.h"
#include "src/sem/builtin.h"
#include "src/sem/call.h"
#include "src/sem/depth_multisampled_texture_type.h"
#include "src/sem/depth_texture_type.h"
#include "src/sem/function.h"
#include "src/sem/member_accessor_expression.h"
#include "src/sem/multisampled_texture_type.h"
#include "src/sem/reference_type.h"
#include "src/sem/sampled_texture_type.h"
#include "src/sem/statement.h"
#include "src/sem/struct.h"
#include "src/sem/type_constructor.h"
#include "src/sem/type_conversion.h"
#include "src/sem/variable.h"
#include "src/sem/vector_type.h"
#include "src/transform/add_empty_entry_point.h"
#include "src/transform/add_spirv_block_attribute.h"
#include "src/transform/canonicalize_entry_point_io.h"
#include "src/transform/external_texture_transform.h"
#include "src/transform/fold_constants.h"
#include "src/transform/for_loop_to_loop.h"
#include "src/transform/manager.h"
#include "src/transform/promote_side_effects_to_decl.h"
#include "src/transform/remove_unreachable_statements.h"
#include "src/transform/simplify_pointers.h"
#include "src/transform/unshadow.h"
#include "src/transform/vectorize_scalar_matrix_constructors.h"
#include "src/transform/zero_init_workgroup_memory.h"
#include "src/utils/defer.h"
#include "src/utils/map.h"
#include "src/writer/append_vector.h"
namespace tint {
namespace writer {
namespace spirv {
namespace {
using BuiltinType = sem::BuiltinType;
const char kGLSLstd450[] = "GLSL.std.450";
uint32_t size_of(const InstructionList& instructions) {
uint32_t size = 0;
for (const auto& inst : instructions)
size += inst.word_length();
return size;
}
uint32_t pipeline_stage_to_execution_model(ast::PipelineStage stage) {
SpvExecutionModel model = SpvExecutionModelVertex;
switch (stage) {
case ast::PipelineStage::kFragment:
model = SpvExecutionModelFragment;
break;
case ast::PipelineStage::kVertex:
model = SpvExecutionModelVertex;
break;
case ast::PipelineStage::kCompute:
model = SpvExecutionModelGLCompute;
break;
case ast::PipelineStage::kNone:
model = SpvExecutionModelMax;
break;
}
return model;
}
bool LastIsFallthrough(const ast::BlockStatement* stmts) {
return !stmts->Empty() && stmts->Last()->Is<ast::FallthroughStatement>();
}
/// Returns the matrix type that is `type` or that is wrapped by
/// one or more levels of an arrays inside of `type`.
/// @param type the given type, which must not be null
/// @returns the nested matrix type, or nullptr if none
const sem::Matrix* GetNestedMatrixType(const sem::Type* type) {
while (auto* arr = type->As<sem::Array>()) {
type = arr->ElemType();
}
return type->As<sem::Matrix>();
}
uint32_t builtin_to_glsl_method(const sem::Builtin* builtin) {
switch (builtin->Type()) {
case BuiltinType::kAcos:
return GLSLstd450Acos;
case BuiltinType::kAsin:
return GLSLstd450Asin;
case BuiltinType::kAtan:
return GLSLstd450Atan;
case BuiltinType::kAtan2:
return GLSLstd450Atan2;
case BuiltinType::kCeil:
return GLSLstd450Ceil;
case BuiltinType::kClamp:
if (builtin->ReturnType()->is_float_scalar_or_vector()) {
return GLSLstd450NClamp;
} else if (builtin->ReturnType()->is_unsigned_scalar_or_vector()) {
return GLSLstd450UClamp;
} else {
return GLSLstd450SClamp;
}
case BuiltinType::kCos:
return GLSLstd450Cos;
case BuiltinType::kCosh:
return GLSLstd450Cosh;
case BuiltinType::kCross:
return GLSLstd450Cross;
case BuiltinType::kDegrees:
return GLSLstd450Degrees;
case BuiltinType::kDeterminant:
return GLSLstd450Determinant;
case BuiltinType::kDistance:
return GLSLstd450Distance;
case BuiltinType::kExp:
return GLSLstd450Exp;
case BuiltinType::kExp2:
return GLSLstd450Exp2;
case BuiltinType::kFaceForward:
return GLSLstd450FaceForward;
case BuiltinType::kFloor:
return GLSLstd450Floor;
case BuiltinType::kFma:
return GLSLstd450Fma;
case BuiltinType::kFract:
return GLSLstd450Fract;
case BuiltinType::kFrexp:
return GLSLstd450FrexpStruct;
case BuiltinType::kInverseSqrt:
return GLSLstd450InverseSqrt;
case BuiltinType::kLdexp:
return GLSLstd450Ldexp;
case BuiltinType::kLength:
return GLSLstd450Length;
case BuiltinType::kLog:
return GLSLstd450Log;
case BuiltinType::kLog2:
return GLSLstd450Log2;
case BuiltinType::kMax:
if (builtin->ReturnType()->is_float_scalar_or_vector()) {
return GLSLstd450NMax;
} else if (builtin->ReturnType()->is_unsigned_scalar_or_vector()) {
return GLSLstd450UMax;
} else {
return GLSLstd450SMax;
}
case BuiltinType::kMin:
if (builtin->ReturnType()->is_float_scalar_or_vector()) {
return GLSLstd450NMin;
} else if (builtin->ReturnType()->is_unsigned_scalar_or_vector()) {
return GLSLstd450UMin;
} else {
return GLSLstd450SMin;
}
case BuiltinType::kMix:
return GLSLstd450FMix;
case BuiltinType::kModf:
return GLSLstd450ModfStruct;
case BuiltinType::kNormalize:
return GLSLstd450Normalize;
case BuiltinType::kPack4x8snorm:
return GLSLstd450PackSnorm4x8;
case BuiltinType::kPack4x8unorm:
return GLSLstd450PackUnorm4x8;
case BuiltinType::kPack2x16snorm:
return GLSLstd450PackSnorm2x16;
case BuiltinType::kPack2x16unorm:
return GLSLstd450PackUnorm2x16;
case BuiltinType::kPack2x16float:
return GLSLstd450PackHalf2x16;
case BuiltinType::kPow:
return GLSLstd450Pow;
case BuiltinType::kRadians:
return GLSLstd450Radians;
case BuiltinType::kReflect:
return GLSLstd450Reflect;
case BuiltinType::kRefract:
return GLSLstd450Refract;
case BuiltinType::kRound:
return GLSLstd450RoundEven;
case BuiltinType::kSign:
return GLSLstd450FSign;
case BuiltinType::kSin:
return GLSLstd450Sin;
case BuiltinType::kSinh:
return GLSLstd450Sinh;
case BuiltinType::kSmoothStep:
return GLSLstd450SmoothStep;
case BuiltinType::kSqrt:
return GLSLstd450Sqrt;
case BuiltinType::kStep:
return GLSLstd450Step;
case BuiltinType::kTan:
return GLSLstd450Tan;
case BuiltinType::kTanh:
return GLSLstd450Tanh;
case BuiltinType::kTrunc:
return GLSLstd450Trunc;
case BuiltinType::kUnpack4x8snorm:
return GLSLstd450UnpackSnorm4x8;
case BuiltinType::kUnpack4x8unorm:
return GLSLstd450UnpackUnorm4x8;
case BuiltinType::kUnpack2x16snorm:
return GLSLstd450UnpackSnorm2x16;
case BuiltinType::kUnpack2x16unorm:
return GLSLstd450UnpackUnorm2x16;
case BuiltinType::kUnpack2x16float:
return GLSLstd450UnpackHalf2x16;
default:
break;
}
return 0;
}
/// @return the vector element type if ty is a vector, otherwise return ty.
const sem::Type* ElementTypeOf(const sem::Type* ty) {
if (auto* v = ty->As<sem::Vector>()) {
return v->type();
}
return ty;
}
} // namespace
SanitizedResult Sanitize(const Program* in,
bool emit_vertex_point_size,
bool disable_workgroup_init) {
transform::Manager manager;
transform::DataMap data;
manager.Add<transform::Unshadow>();
if (!disable_workgroup_init) {
manager.Add<transform::ZeroInitWorkgroupMemory>();
}
manager.Add<transform::RemoveUnreachableStatements>();
manager.Add<transform::SimplifyPointers>(); // Required for arrayLength()
manager.Add<transform::FoldConstants>();
manager.Add<transform::ExternalTextureTransform>();
manager.Add<transform::VectorizeScalarMatrixConstructors>();
manager.Add<transform::ForLoopToLoop>(); // Must come after
// ZeroInitWorkgroupMemory
manager.Add<transform::CanonicalizeEntryPointIO>();
manager.Add<transform::AddEmptyEntryPoint>();
manager.Add<transform::AddSpirvBlockAttribute>();
data.Add<transform::PromoteSideEffectsToDecl::Config>(
/* type_ctor_to_let */ false, /* dynamic_index_to_var */ true);
manager.Add<transform::PromoteSideEffectsToDecl>();
data.Add<transform::CanonicalizeEntryPointIO::Config>(
transform::CanonicalizeEntryPointIO::Config(
transform::CanonicalizeEntryPointIO::ShaderStyle::kSpirv, 0xFFFFFFFF,
emit_vertex_point_size));
SanitizedResult result;
result.program = std::move(manager.Run(in, data).program);
return result;
}
Builder::AccessorInfo::AccessorInfo() : source_id(0), source_type(nullptr) {}
Builder::AccessorInfo::~AccessorInfo() {}
Builder::Builder(const Program* program)
: builder_(ProgramBuilder::Wrap(program)), scope_stack_({}) {}
Builder::~Builder() = default;
bool Builder::Build() {
push_capability(SpvCapabilityShader);
push_memory_model(spv::Op::OpMemoryModel,
{Operand::Int(SpvAddressingModelLogical),
Operand::Int(SpvMemoryModelGLSL450)});
for (auto* var : builder_.AST().GlobalVariables()) {
if (!GenerateGlobalVariable(var)) {
return false;
}
}
for (auto* func : builder_.AST().Functions()) {
if (!GenerateFunction(func)) {
return false;
}
}
return true;
}
Operand Builder::result_op() {
return Operand::Int(next_id());
}
uint32_t Builder::total_size() const {
// The 5 covers the magic, version, generator, id bound and reserved.
uint32_t size = 5;
size += size_of(capabilities_);
size += size_of(extensions_);
size += size_of(ext_imports_);
size += size_of(memory_model_);
size += size_of(entry_points_);
size += size_of(execution_modes_);
size += size_of(debug_);
size += size_of(annotations_);
size += size_of(types_);
for (const auto& func : functions_) {
size += func.word_length();
}
return size;
}
void Builder::iterate(std::function<void(const Instruction&)> cb) const {
for (const auto& inst : capabilities_) {
cb(inst);
}
for (const auto& inst : extensions_) {
cb(inst);
}
for (const auto& inst : ext_imports_) {
cb(inst);
}
for (const auto& inst : memory_model_) {
cb(inst);
}
for (const auto& inst : entry_points_) {
cb(inst);
}
for (const auto& inst : execution_modes_) {
cb(inst);
}
for (const auto& inst : debug_) {
cb(inst);
}
for (const auto& inst : annotations_) {
cb(inst);
}
for (const auto& inst : types_) {
cb(inst);
}
for (const auto& func : functions_) {
func.iterate(cb);
}
}
void Builder::push_capability(uint32_t cap) {
if (capability_set_.count(cap) == 0) {
capability_set_.insert(cap);
capabilities_.push_back(
Instruction{spv::Op::OpCapability, {Operand::Int(cap)}});
}
}
bool Builder::GenerateLabel(uint32_t id) {
if (!push_function_inst(spv::Op::OpLabel, {Operand::Int(id)})) {
return false;
}
current_label_id_ = id;
return true;
}
bool Builder::GenerateAssignStatement(const ast::AssignmentStatement* assign) {
if (assign->lhs->Is<ast::PhonyExpression>()) {
auto rhs_id = GenerateExpression(assign->rhs);
if (rhs_id == 0) {
return false;
}
return true;
} else {
auto lhs_id = GenerateExpression(assign->lhs);
if (lhs_id == 0) {
return false;
}
auto rhs_id = GenerateExpressionWithLoadIfNeeded(assign->rhs);
if (rhs_id == 0) {
return false;
}
return GenerateStore(lhs_id, rhs_id);
}
}
bool Builder::GenerateBreakStatement(const ast::BreakStatement*) {
if (merge_stack_.empty()) {
error_ = "Attempted to break without a merge block";
return false;
}
if (!push_function_inst(spv::Op::OpBranch,
{Operand::Int(merge_stack_.back())})) {
return false;
}
return true;
}
bool Builder::GenerateContinueStatement(const ast::ContinueStatement*) {
if (continue_stack_.empty()) {
error_ = "Attempted to continue without a continue block";
return false;
}
if (!push_function_inst(spv::Op::OpBranch,
{Operand::Int(continue_stack_.back())})) {
return false;
}
return true;
}
// TODO(dsinclair): This is generating an OpKill but the semantics of kill
// haven't been defined for WGSL yet. So, this may need to change.
// https://github.com/gpuweb/gpuweb/issues/676
bool Builder::GenerateDiscardStatement(const ast::DiscardStatement*) {
if (!push_function_inst(spv::Op::OpKill, {})) {
return false;
}
return true;
}
bool Builder::GenerateEntryPoint(const ast::Function* func, uint32_t id) {
auto stage = pipeline_stage_to_execution_model(func->PipelineStage());
if (stage == SpvExecutionModelMax) {
error_ = "Unknown pipeline stage provided";
return false;
}
OperandList operands = {
Operand::Int(stage), Operand::Int(id),
Operand::String(builder_.Symbols().NameFor(func->symbol))};
auto* func_sem = builder_.Sem().Get(func);
for (const auto* var : func_sem->TransitivelyReferencedGlobals()) {
// For SPIR-V 1.3 we only output Input/output variables. If we update to
// SPIR-V 1.4 or later this should be all variables.
if (var->StorageClass() != ast::StorageClass::kInput &&
var->StorageClass() != ast::StorageClass::kOutput) {
continue;
}
uint32_t var_id = scope_stack_.Get(var->Declaration()->symbol);
if (var_id == 0) {
error_ = "unable to find ID for global variable: " +
builder_.Symbols().NameFor(var->Declaration()->symbol);
return false;
}
operands.push_back(Operand::Int(var_id));
}
push_entry_point(spv::Op::OpEntryPoint, operands);
return true;
}
bool Builder::GenerateExecutionModes(const ast::Function* func, uint32_t id) {
auto* func_sem = builder_.Sem().Get(func);
// WGSL fragment shader origin is upper left
if (func->PipelineStage() == ast::PipelineStage::kFragment) {
push_execution_mode(
spv::Op::OpExecutionMode,
{Operand::Int(id), Operand::Int(SpvExecutionModeOriginUpperLeft)});
} else if (func->PipelineStage() == ast::PipelineStage::kCompute) {
auto& wgsize = func_sem->WorkgroupSize();
// Check if the workgroup_size uses pipeline-overridable constants.
if (wgsize[0].overridable_const || wgsize[1].overridable_const ||
wgsize[2].overridable_const) {
if (has_overridable_workgroup_size_) {
// Only one stage can have a pipeline-overridable workgroup size.
// TODO(crbug.com/tint/810): Use LocalSizeId to handle this scenario.
TINT_ICE(Writer, builder_.Diagnostics())
<< "multiple stages using pipeline-overridable workgroup sizes";
}
has_overridable_workgroup_size_ = true;
auto* vec3_u32 =
builder_.create<sem::Vector>(builder_.create<sem::U32>(), 3);
uint32_t vec3_u32_type_id = GenerateTypeIfNeeded(vec3_u32);
if (vec3_u32_type_id == 0) {
return 0;
}
OperandList wgsize_ops;
auto wgsize_result = result_op();
wgsize_ops.push_back(Operand::Int(vec3_u32_type_id));
wgsize_ops.push_back(wgsize_result);
// Generate OpConstant instructions for each dimension.
for (int i = 0; i < 3; i++) {
auto constant = ScalarConstant::U32(wgsize[i].value);
if (wgsize[i].overridable_const) {
// Make the constant specializable.
auto* sem_const = builder_.Sem().Get<sem::GlobalVariable>(
wgsize[i].overridable_const);
if (!sem_const->IsOverridable()) {
TINT_ICE(Writer, builder_.Diagnostics())
<< "expected a pipeline-overridable constant";
}
constant.is_spec_op = true;
constant.constant_id = sem_const->ConstantId();
}
auto result = GenerateConstantIfNeeded(constant);
wgsize_ops.push_back(Operand::Int(result));
}
// Generate the WorkgroupSize builtin.
push_type(spv::Op::OpSpecConstantComposite, wgsize_ops);
push_annot(spv::Op::OpDecorate,
{wgsize_result, Operand::Int(SpvDecorationBuiltIn),
Operand::Int(SpvBuiltInWorkgroupSize)});
} else {
// Not overridable, so just use OpExecutionMode LocalSize.
uint32_t x = wgsize[0].value;
uint32_t y = wgsize[1].value;
uint32_t z = wgsize[2].value;
push_execution_mode(
spv::Op::OpExecutionMode,
{Operand::Int(id), Operand::Int(SpvExecutionModeLocalSize),
Operand::Int(x), Operand::Int(y), Operand::Int(z)});
}
}
for (auto builtin : func_sem->TransitivelyReferencedBuiltinVariables()) {
if (builtin.second->builtin == ast::Builtin::kFragDepth) {
push_execution_mode(
spv::Op::OpExecutionMode,
{Operand::Int(id), Operand::Int(SpvExecutionModeDepthReplacing)});
}
}
return true;
}
uint32_t Builder::GenerateExpression(const ast::Expression* expr) {
return Switch(
expr,
[&](const ast::IndexAccessorExpression* a) { //
return GenerateAccessorExpression(a);
},
[&](const ast::BinaryExpression* b) { //
return GenerateBinaryExpression(b);
},
[&](const ast::BitcastExpression* b) { //
return GenerateBitcastExpression(b);
},
[&](const ast::CallExpression* c) { //
return GenerateCallExpression(c);
},
[&](const ast::IdentifierExpression* i) { //
return GenerateIdentifierExpression(i);
},
[&](const ast::LiteralExpression* l) { //
return GenerateLiteralIfNeeded(nullptr, l);
},
[&](const ast::MemberAccessorExpression* m) { //
return GenerateAccessorExpression(m);
},
[&](const ast::UnaryOpExpression* u) { //
return GenerateUnaryOpExpression(u);
},
[&](Default) -> uint32_t {
error_ =
"unknown expression type: " + std::string(expr->TypeInfo().name);
return 0;
});
}
bool Builder::GenerateFunction(const ast::Function* func_ast) {
auto* func = builder_.Sem().Get(func_ast);
uint32_t func_type_id = GenerateFunctionTypeIfNeeded(func);
if (func_type_id == 0) {
return false;
}
auto func_op = result_op();
auto func_id = func_op.to_i();
push_debug(spv::Op::OpName,
{Operand::Int(func_id),
Operand::String(builder_.Symbols().NameFor(func_ast->symbol))});
auto ret_id = GenerateTypeIfNeeded(func->ReturnType());
if (ret_id == 0) {
return false;
}
scope_stack_.Push();
TINT_DEFER(scope_stack_.Pop());
auto definition_inst = Instruction{
spv::Op::OpFunction,
{Operand::Int(ret_id), func_op, Operand::Int(SpvFunctionControlMaskNone),
Operand::Int(func_type_id)}};
InstructionList params;
for (auto* param : func->Parameters()) {
auto param_op = result_op();
auto param_id = param_op.to_i();
auto param_type_id = GenerateTypeIfNeeded(param->Type());
if (param_type_id == 0) {
return false;
}
push_debug(spv::Op::OpName, {Operand::Int(param_id),
Operand::String(builder_.Symbols().NameFor(
param->Declaration()->symbol))});
params.push_back(Instruction{spv::Op::OpFunctionParameter,
{Operand::Int(param_type_id), param_op}});
scope_stack_.Set(param->Declaration()->symbol, param_id);
}
push_function(Function{definition_inst, result_op(), std::move(params)});
for (auto* stmt : func_ast->body->statements) {
if (!GenerateStatement(stmt)) {
return false;
}
}
if (InsideBasicBlock()) {
if (func->ReturnType()->Is<sem::Void>()) {
push_function_inst(spv::Op::OpReturn, {});
} else {
auto zero = GenerateConstantNullIfNeeded(func->ReturnType());
push_function_inst(spv::Op::OpReturnValue, {Operand::Int(zero)});
}
}
if (func_ast->IsEntryPoint()) {
if (!GenerateEntryPoint(func_ast, func_id)) {
return false;
}
if (!GenerateExecutionModes(func_ast, func_id)) {
return false;
}
}
func_symbol_to_id_[func_ast->symbol] = func_id;
return true;
}
uint32_t Builder::GenerateFunctionTypeIfNeeded(const sem::Function* func) {
return utils::GetOrCreate(
func_sig_to_id_, func->Signature(), [&]() -> uint32_t {
auto func_op = result_op();
auto func_type_id = func_op.to_i();
auto ret_id = GenerateTypeIfNeeded(func->ReturnType());
if (ret_id == 0) {
return 0;
}
OperandList ops = {func_op, Operand::Int(ret_id)};
for (auto* param : func->Parameters()) {
auto param_type_id = GenerateTypeIfNeeded(param->Type());
if (param_type_id == 0) {
return 0;
}
ops.push_back(Operand::Int(param_type_id));
}
push_type(spv::Op::OpTypeFunction, std::move(ops));
return func_type_id;
});
}
bool Builder::GenerateFunctionVariable(const ast::Variable* var) {
uint32_t init_id = 0;
if (var->constructor) {
init_id = GenerateExpressionWithLoadIfNeeded(var->constructor);
if (init_id == 0) {
return false;
}
}
if (var->is_const) {
if (!var->constructor) {
error_ = "missing constructor for constant";
return false;
}
scope_stack_.Set(var->symbol, init_id);
spirv_id_to_variable_[init_id] = var;
return true;
}
auto result = result_op();
auto var_id = result.to_i();
auto sc = ast::StorageClass::kFunction;
auto* type = builder_.Sem().Get(var)->Type();
auto type_id = GenerateTypeIfNeeded(type);
if (type_id == 0) {
return false;
}
push_debug(spv::Op::OpName,
{Operand::Int(var_id),
Operand::String(builder_.Symbols().NameFor(var->symbol))});
// TODO(dsinclair) We could detect if the constructor is fully const and emit
// an initializer value for the variable instead of doing the OpLoad.
auto null_id = GenerateConstantNullIfNeeded(type->UnwrapRef());
if (null_id == 0) {
return 0;
}
push_function_var({Operand::Int(type_id), result,
Operand::Int(ConvertStorageClass(sc)),
Operand::Int(null_id)});
if (var->constructor) {
if (!GenerateStore(var_id, init_id)) {
return false;
}
}
scope_stack_.Set(var->symbol, var_id);
spirv_id_to_variable_[var_id] = var;
return true;
}
bool Builder::GenerateStore(uint32_t to, uint32_t from) {
return push_function_inst(spv::Op::OpStore,
{Operand::Int(to), Operand::Int(from)});
}
bool Builder::GenerateGlobalVariable(const ast::Variable* var) {
auto* sem = builder_.Sem().Get(var);
auto* type = sem->Type()->UnwrapRef();
uint32_t init_id = 0;
if (var->constructor) {
init_id = GenerateConstructorExpression(var, var->constructor);
if (init_id == 0) {
return false;
}
}
if (var->is_const) {
if (!var->constructor) {
// Constants must have an initializer unless they have an override
// attribute.
if (!ast::HasAttribute<ast::OverrideAttribute>(var->attributes)) {
error_ = "missing constructor for constant";
return false;
}
// SPIR-V requires specialization constants to have initializers.
if (type->Is<sem::F32>()) {
ast::FloatLiteralExpression l(ProgramID(), Source{}, 0.0f);
init_id = GenerateLiteralIfNeeded(var, &l);
} else if (type->Is<sem::U32>()) {
ast::UintLiteralExpression l(ProgramID(), Source{}, 0);
init_id = GenerateLiteralIfNeeded(var, &l);
} else if (type->Is<sem::I32>()) {
ast::SintLiteralExpression l(ProgramID(), Source{}, 0);
init_id = GenerateLiteralIfNeeded(var, &l);
} else if (type->Is<sem::Bool>()) {
ast::BoolLiteralExpression l(ProgramID(), Source{}, false);
init_id = GenerateLiteralIfNeeded(var, &l);
} else {
error_ = "invalid type for pipeline constant ID, must be scalar";
return false;
}
if (init_id == 0) {
return 0;
}
}
push_debug(spv::Op::OpName,
{Operand::Int(init_id),
Operand::String(builder_.Symbols().NameFor(var->symbol))});
scope_stack_.Set(var->symbol, init_id);
spirv_id_to_variable_[init_id] = var;
return true;
}
auto result = result_op();
auto var_id = result.to_i();
auto sc = sem->StorageClass() == ast::StorageClass::kNone
? ast::StorageClass::kPrivate
: sem->StorageClass();
auto type_id = GenerateTypeIfNeeded(sem->Type());
if (type_id == 0) {
return false;
}
push_debug(spv::Op::OpName,
{Operand::Int(var_id),
Operand::String(builder_.Symbols().NameFor(var->symbol))});
OperandList ops = {Operand::Int(type_id), result,
Operand::Int(ConvertStorageClass(sc))};
if (var->constructor) {
ops.push_back(Operand::Int(init_id));
} else {
auto* st = type->As<sem::StorageTexture>();
if (st || type->Is<sem::Struct>()) {
// type is a sem::Struct or a sem::StorageTexture
auto access = st ? st->access() : sem->Access();
switch (access) {
case ast::Access::kWrite:
push_annot(
spv::Op::OpDecorate,
{Operand::Int(var_id), Operand::Int(SpvDecorationNonReadable)});
break;
case ast::Access::kRead:
push_annot(
spv::Op::OpDecorate,
{Operand::Int(var_id), Operand::Int(SpvDecorationNonWritable)});
break;
case ast::Access::kUndefined:
case ast::Access::kReadWrite:
break;
}
}
if (!type->Is<sem::Sampler>()) {
// If we don't have a constructor and we're an Output or Private
// variable, then WGSL requires that we zero-initialize.
if (sem->StorageClass() == ast::StorageClass::kPrivate ||
sem->StorageClass() == ast::StorageClass::kOutput) {
init_id = GenerateConstantNullIfNeeded(type);
if (init_id == 0) {
return 0;
}
ops.push_back(Operand::Int(init_id));
}
}
}
push_type(spv::Op::OpVariable, std::move(ops));
for (auto* attr : var->attributes) {
bool ok = Switch(
attr,
[&](const ast::BuiltinAttribute* builtin) {
push_annot(spv::Op::OpDecorate,
{Operand::Int(var_id), Operand::Int(SpvDecorationBuiltIn),
Operand::Int(ConvertBuiltin(builtin->builtin,
sem->StorageClass()))});
return true;
},
[&](const ast::LocationAttribute* location) {
push_annot(spv::Op::OpDecorate,
{Operand::Int(var_id), Operand::Int(SpvDecorationLocation),
Operand::Int(location->value)});
return true;
},
[&](const ast::InterpolateAttribute* interpolate) {
AddInterpolationDecorations(var_id, interpolate->type,
interpolate->sampling);
return true;
},
[&](const ast::InvariantAttribute*) {
push_annot(
spv::Op::OpDecorate,
{Operand::Int(var_id), Operand::Int(SpvDecorationInvariant)});
return true;
},
[&](const ast::BindingAttribute* binding) {
push_annot(spv::Op::OpDecorate,
{Operand::Int(var_id), Operand::Int(SpvDecorationBinding),
Operand::Int(binding->value)});
return true;
},
[&](const ast::GroupAttribute* group) {
push_annot(
spv::Op::OpDecorate,
{Operand::Int(var_id), Operand::Int(SpvDecorationDescriptorSet),
Operand::Int(group->value)});
return true;
},
[&](const ast::OverrideAttribute*) {
return true; // Spec constants are handled elsewhere
},
[&](const ast::InternalAttribute*) {
return true; // ignored
},
[&](Default) {
error_ = "unknown attribute";
return false;
});
if (!ok) {
return false;
}
}
scope_stack_.Set(var->symbol, var_id);
spirv_id_to_variable_[var_id] = var;
return true;
}
bool Builder::GenerateIndexAccessor(const ast::IndexAccessorExpression* expr,
AccessorInfo* info) {
auto idx_id = GenerateExpressionWithLoadIfNeeded(expr->index);
if (idx_id == 0) {
return 0;
}
// If the source is a reference, we access chain into it.
// In the future, pointers may support access-chaining.
// See https://github.com/gpuweb/gpuweb/pull/1580
if (info->source_type->Is<sem::Reference>()) {
info->access_chain_indices.push_back(idx_id);
info->source_type = TypeOf(expr);
return true;
}
auto result_type_id = GenerateTypeIfNeeded(TypeOf(expr));
if (result_type_id == 0) {
return false;
}
// We don't have a pointer, so we can just directly extract the value.
auto extract = result_op();
auto extract_id = extract.to_i();
// If the index is compile-time constant, we use OpCompositeExtract.
auto* idx = builder_.Sem().Get(expr->index);
if (auto idx_constval = idx->ConstantValue()) {
if (!push_function_inst(
spv::Op::OpCompositeExtract,
{
Operand::Int(result_type_id),
extract,
Operand::Int(info->source_id),
Operand::Int(idx_constval.ElementAs<uint32_t>(0)),
})) {
return false;
}
info->source_id = extract_id;
info->source_type = TypeOf(expr);
return true;
}
// If the source is a vector, we use OpVectorExtractDynamic.
if (info->source_type->Is<sem::Vector>()) {
if (!push_function_inst(
spv::Op::OpVectorExtractDynamic,
{Operand::Int(result_type_id), extract,
Operand::Int(info->source_id), Operand::Int(idx_id)})) {
return false;
}
info->source_id = extract_id;
info->source_type = TypeOf(expr);
return true;
}
TINT_ICE(Writer, builder_.Diagnostics())
<< "unsupported index accessor expression";
return false;
}
bool Builder::GenerateMemberAccessor(const ast::MemberAccessorExpression* expr,
AccessorInfo* info) {
auto* expr_sem = builder_.Sem().Get(expr);
auto* expr_type = expr_sem->Type();
if (auto* access = expr_sem->As<sem::StructMemberAccess>()) {
uint32_t idx = access->Member()->Index();
if (info->source_type->Is<sem::Reference>()) {
auto idx_id = GenerateConstantIfNeeded(ScalarConstant::U32(idx));
if (idx_id == 0) {
return 0;
}
info->access_chain_indices.push_back(idx_id);
info->source_type = expr_type;
} else {
auto result_type_id = GenerateTypeIfNeeded(expr_type);
if (result_type_id == 0) {
return false;
}
auto extract = result_op();
auto extract_id = extract.to_i();
if (!push_function_inst(
spv::Op::OpCompositeExtract,
{Operand::Int(result_type_id), extract,
Operand::Int(info->source_id), Operand::Int(idx)})) {
return false;
}
info->source_id = extract_id;
info->source_type = expr_type;
}
return true;
}
if (auto* swizzle = expr_sem->As<sem::Swizzle>()) {
// Single element swizzle is either an access chain or a composite extract
auto& indices = swizzle->Indices();
if (indices.size() == 1) {
if (info->source_type->Is<sem::Reference>()) {
auto idx_id = GenerateConstantIfNeeded(ScalarConstant::U32(indices[0]));
if (idx_id == 0) {
return 0;
}
info->access_chain_indices.push_back(idx_id);
} else {
auto result_type_id = GenerateTypeIfNeeded(expr_type);
if (result_type_id == 0) {
return 0;
}
auto extract = result_op();
auto extract_id = extract.to_i();
if (!push_function_inst(
spv::Op::OpCompositeExtract,
{Operand::Int(result_type_id), extract,
Operand::Int(info->source_id), Operand::Int(indices[0])})) {
return false;
}
info->source_id = extract_id;
info->source_type = expr_type;
}
return true;
}
// Store the type away as it may change if we run the access chain
auto* incoming_type = info->source_type;
// Multi-item extract is a VectorShuffle. We have to emit any existing
// access chain data, then load the access chain and shuffle that.
if (!info->access_chain_indices.empty()) {
auto result_type_id = GenerateTypeIfNeeded(info->source_type);
if (result_type_id == 0) {
return 0;
}
auto extract = result_op();
auto extract_id = extract.to_i();
OperandList ops = {Operand::Int(result_type_id), extract,
Operand::Int(info->source_id)};
for (auto id : info->access_chain_indices) {
ops.push_back(Operand::Int(id));
}
if (!push_function_inst(spv::Op::OpAccessChain, ops)) {
return false;
}
info->source_id = GenerateLoadIfNeeded(expr_type, extract_id);
info->source_type = expr_type->UnwrapRef();
info->access_chain_indices.clear();
}
auto result_type_id = GenerateTypeIfNeeded(expr_type);
if (result_type_id == 0) {
return false;
}
auto vec_id = GenerateLoadIfNeeded(incoming_type, info->source_id);
auto result = result_op();
auto result_id = result.to_i();
OperandList ops = {Operand::Int(result_type_id), result,
Operand::Int(vec_id), Operand::Int(vec_id)};
for (auto idx : indices) {
ops.push_back(Operand::Int(idx));
}
if (!push_function_inst(spv::Op::OpVectorShuffle, ops)) {
return false;
}
info->source_id = result_id;
info->source_type = expr_type;
return true;
}
TINT_ICE(Writer, builder_.Diagnostics())
<< "unhandled member index type: " << expr_sem->TypeInfo().name;
return false;
}
uint32_t Builder::GenerateAccessorExpression(const ast::Expression* expr) {
if (!expr->IsAnyOf<ast::IndexAccessorExpression,
ast::MemberAccessorExpression>()) {
TINT_ICE(Writer, builder_.Diagnostics()) << "expression is not an accessor";
return 0;
}
// Gather a list of all the member and index accessors that are in this chain.
// The list is built in reverse order as that's the order we need to access
// the chain.
std::vector<const ast::Expression*> accessors;
const ast::Expression* source = expr;
while (true) {
if (auto* array = source->As<ast::IndexAccessorExpression>()) {
accessors.insert(accessors.begin(), source);
source = array->object;
} else if (auto* member = source->As<ast::MemberAccessorExpression>()) {
accessors.insert(accessors.begin(), source);
source = member->structure;
} else {
break;
}
}
AccessorInfo info;
info.source_id = GenerateExpression(source);
if (info.source_id == 0) {
return 0;
}
info.source_type = TypeOf(source);
// Note: Dynamic index on array and matrix values (lets) should have been
// promoted to storage with the VarForDynamicIndex transform.
for (auto* accessor : accessors) {
bool ok = Switch(
accessor,
[&](const ast::IndexAccessorExpression* array) {
return GenerateIndexAccessor(array, &info);
},
[&](const ast::MemberAccessorExpression* member) {
return GenerateMemberAccessor(member, &info);
},
[&](Default) {
error_ = "invalid accessor in list: " +
std::string(accessor->TypeInfo().name);
return false;
});
if (!ok) {
return false;
}
}
if (!info.access_chain_indices.empty()) {
auto* type = TypeOf(expr);
auto result_type_id = GenerateTypeIfNeeded(type);
if (result_type_id == 0) {
return 0;
}
auto result = result_op();
auto result_id = result.to_i();
OperandList ops = {Operand::Int(result_type_id), result,
Operand::Int(info.source_id)};
for (auto id : info.access_chain_indices) {
ops.push_back(Operand::Int(id));
}
if (!push_function_inst(spv::Op::OpAccessChain, ops)) {
return false;
}
info.source_id = result_id;
}
return info.source_id;
}
uint32_t Builder::GenerateIdentifierExpression(
const ast::IdentifierExpression* expr) {
uint32_t val = scope_stack_.Get(expr->symbol);
if (val == 0) {
error_ = "unable to find variable with identifier: " +
builder_.Symbols().NameFor(expr->symbol);
}
return val;
}
uint32_t Builder::GenerateExpressionWithLoadIfNeeded(
const sem::Expression* expr) {
// The semantic node directly knows both the AST node and the resolved type.
if (const auto id = GenerateExpression(expr->Declaration())) {
return GenerateLoadIfNeeded(expr->Type(), id);
}
return 0;
}
uint32_t Builder::GenerateExpressionWithLoadIfNeeded(
const ast::Expression* expr) {
if (const auto id = GenerateExpression(expr)) {
// Perform a lookup to get the resolved type.
return GenerateLoadIfNeeded(TypeOf(expr), id);
}
return 0;
}
uint32_t Builder::GenerateLoadIfNeeded(const sem::Type* type, uint32_t id) {
if (auto* ref = type->As<sem::Reference>()) {
type = ref->StoreType();
} else {
return id;
}
auto type_id = GenerateTypeIfNeeded(type);
auto result = result_op();
auto result_id = result.to_i();
if (!push_function_inst(spv::Op::OpLoad,
{Operand::Int(type_id), result, Operand::Int(id)})) {
return 0;
}
return result_id;
}
uint32_t Builder::GenerateUnaryOpExpression(
const ast::UnaryOpExpression* expr) {
auto result = result_op();
auto result_id = result.to_i();
spv::Op op = spv::Op::OpNop;
switch (expr->op) {
case ast::UnaryOp::kComplement:
op = spv::Op::OpNot;
break;
case ast::UnaryOp::kNegation:
if (TypeOf(expr)->is_float_scalar_or_vector()) {
op = spv::Op::OpFNegate;
} else {
op = spv::Op::OpSNegate;
}
break;
case ast::UnaryOp::kNot:
op = spv::Op::OpLogicalNot;
break;
case ast::UnaryOp::kAddressOf:
case ast::UnaryOp::kIndirection:
// Address-of converts a reference to a pointer, and dereference converts
// a pointer to a reference. These are the same thing in SPIR-V, so this
// is a no-op.
return GenerateExpression(expr->expr);
}
auto val_id = GenerateExpressionWithLoadIfNeeded(expr->expr);
if (val_id == 0) {
return 0;
}
auto type_id = GenerateTypeIfNeeded(TypeOf(expr));
if (type_id == 0) {
return 0;
}
if (!push_function_inst(
op, {Operand::Int(type_id), result, Operand::Int(val_id)})) {
return false;
}
return result_id;
}
uint32_t Builder::GetGLSLstd450Import() {
auto where = import_name_to_id_.find(kGLSLstd450);
if (where != import_name_to_id_.end()) {
return where->second;
}
// It doesn't exist yet. Generate it.
auto result = result_op();
auto id = result.to_i();
push_ext_import(spv::Op::OpExtInstImport,
{result, Operand::String(kGLSLstd450)});
// Remember it for later.
import_name_to_id_[kGLSLstd450] = id;
return id;
}
uint32_t Builder::GenerateConstructorExpression(const ast::Variable* var,
const ast::Expression* expr) {
if (auto* literal = expr->As<ast::LiteralExpression>()) {
return GenerateLiteralIfNeeded(var, literal);
}
if (auto* call = builder_.Sem().Get<sem::Call>(expr)) {
if (call->Target()->IsAnyOf<sem::TypeConstructor, sem::TypeConversion>()) {
return GenerateTypeConstructorOrConversion(call, var);
}
}
error_ = "unknown constructor expression";
return 0;
}
bool Builder::IsConstructorConst(const ast::Expression* expr) {
bool is_const = true;
ast::TraverseExpressions(expr, builder_.Diagnostics(),
[&](const ast::Expression* e) {
if (e->Is<ast::LiteralExpression>()) {
return ast::TraverseAction::Descend;
}
if (auto* ce = e->As<ast::CallExpression>()) {
auto* call = builder_.Sem().Get(ce);
if (call->Target()->Is<sem::TypeConstructor>()) {
return ast::TraverseAction::Descend;
}
}
is_const = false;
return ast::TraverseAction::Stop;
});
return is_const;
}
uint32_t Builder::GenerateTypeConstructorOrConversion(
const sem::Call* call,
const ast::Variable* var) {
auto& args = call->Arguments();
auto* global_var = builder_.Sem().Get<sem::GlobalVariable>(var);
auto* result_type = call->Type();
// Generate the zero initializer if there are no values provided.
if (args.empty()) {
if (global_var && global_var->IsOverridable()) {
auto constant_id = global_var->ConstantId();
if (result_type->Is<sem::I32>()) {
return GenerateConstantIfNeeded(
ScalarConstant::I32(0).AsSpecOp(constant_id));
}
if (result_type->Is<sem::U32>()) {
return GenerateConstantIfNeeded(
ScalarConstant::U32(0).AsSpecOp(constant_id));
}
if (result_type->Is<sem::F32>()) {
return GenerateConstantIfNeeded(
ScalarConstant::F32(0).AsSpecOp(constant_id));
}
if (result_type->Is<sem::Bool>()) {
return GenerateConstantIfNeeded(
ScalarConstant::Bool(false).AsSpecOp(constant_id));
}
}
return GenerateConstantNullIfNeeded(result_type->UnwrapRef());
}
std::ostringstream out;
out << "__const_" << result_type->FriendlyName(builder_.Symbols()) << "_";
result_type = result_type->UnwrapRef();
bool constructor_is_const = IsConstructorConst(call->Declaration());
if (has_error()) {
return 0;
}
bool can_cast_or_copy = result_type->is_scalar();
if (auto* res_vec = result_type->As<sem::Vector>()) {
if (res_vec->type()->is_scalar()) {
auto* value_type = args[0]->Type()->UnwrapRef();
if (auto* val_vec = value_type->As<sem::Vector>()) {
if (val_vec->type()->is_scalar()) {
can_cast_or_copy = res_vec->Width() == val_vec->Width();
}
}
}
}
if (can_cast_or_copy) {
return GenerateCastOrCopyOrPassthrough(result_type, args[0]->Declaration(),
global_var);
}
auto type_id = GenerateTypeIfNeeded(result_type);
if (type_id == 0) {
return 0;
}
bool result_is_constant_composite = constructor_is_const;
bool result_is_spec_composite = false;
if (auto* vec = result_type->As<sem::Vector>()) {
result_type = vec->type();
}
OperandList ops;
for (auto* e : args) {
uint32_t id = 0;
id = GenerateExpressionWithLoadIfNeeded(e);
if (id == 0) {
return 0;
}
auto* value_type = e->Type()->UnwrapRef();
// If the result and value types are the same we can just use the object.
// If the result is not a vector then we should have validated that the
// value type is a correctly sized vector so we can just use it directly.
if (result_type == value_type || result_type->Is<sem::Matrix>() ||
result_type->Is<sem::Array>() || result_type->Is<sem::Struct>()) {
out << "_" << id;
ops.push_back(Operand::Int(id));
continue;
}
// Both scalars, but not the same type so we need to generate a conversion
// of the value.
if (value_type->is_scalar() && result_type->is_scalar()) {
id = GenerateCastOrCopyOrPassthrough(result_type, args[0]->Declaration(),
global_var);
out << "_" << id;
ops.push_back(Operand::Int(id));
continue;
}
// When handling vectors as the values there a few cases to take into
// consideration:
// 1. Module scoped vec3<f32>(vec2<f32>(1, 2), 3) -> OpSpecConstantOp
// 2. Function scoped vec3<f32>(vec2<f32>(1, 2), 3) -> OpCompositeExtract
// 3. Either array<vec3<f32>, 1>(vec3<f32>(1, 2, 3)) -> use the ID.
// -> handled above
//
// For cases 1 and 2, if the type is different we also may need to insert
// a type cast.
if (auto* vec = value_type->As<sem::Vector>()) {
auto* vec_type = vec->type();
auto value_type_id = GenerateTypeIfNeeded(vec_type);
if (value_type_id == 0) {
return 0;
}
for (uint32_t i = 0; i < vec->Width(); ++i) {
auto extract = result_op();
auto extract_id = extract.to_i();
if (!global_var) {
// A non-global initializer. Case 2.
if (!push_function_inst(spv::Op::OpCompositeExtract,
{Operand::Int(value_type_id), extract,
Operand::Int(id), Operand::Int(i)})) {
return false;
}
// We no longer have a constant composite, but have to do a
// composite construction as these calls are inside a function.
result_is_constant_composite = false;
} else {
// A global initializer, must use OpSpecConstantOp. Case 1.
auto idx_id = GenerateConstantIfNeeded(ScalarConstant::U32(i));
if (idx_id == 0) {
return 0;
}
push_type(spv::Op::OpSpecConstantOp,
{Operand::Int(value_type_id), extract,
Operand::Int(SpvOpCompositeExtract), Operand::Int(id),
Operand::Int(idx_id)});
result_is_spec_composite = true;
}
out << "_" << extract_id;
ops.push_back(Operand::Int(extract_id));
}
} else {
error_ = "Unhandled type cast value type";
return 0;
}
}
// For a single-value vector initializer, splat the initializer value.
auto* const init_result_type = call->Type()->UnwrapRef();
if (args.size() == 1 && init_result_type->is_scalar_vector() &&
args[0]->Type()->UnwrapRef()->is_scalar()) {
size_t vec_size = init_result_type->As<sem::Vector>()->Width();
for (size_t i = 0; i < (vec_size - 1); ++i) {
ops.push_back(ops[0]);
}
}
auto str = out.str();
auto val = type_constructor_to_id_.find(str);
if (val != type_constructor_to_id_.end()) {
return val->second;
}
auto result = result_op();
ops.insert(ops.begin(), result);
ops.insert(ops.begin(), Operand::Int(type_id));
type_constructor_to_id_[str] = result.to_i();
if (result_is_spec_composite) {
push_type(spv::Op::OpSpecConstantComposite, ops);
} else if (result_is_constant_composite) {
push_type(spv::Op::OpConstantComposite, ops);
} else {
if (!push_function_inst(spv::Op::OpCompositeConstruct, ops)) {
return 0;
}
}
return result.to_i();
}
uint32_t Builder::GenerateCastOrCopyOrPassthrough(
const sem::Type* to_type,
const ast::Expression* from_expr,
bool is_global_init) {
// This should not happen as we rely on constant folding to obviate
// casts/conversions for module-scope variables
if (is_global_init) {
TINT_ICE(Writer, builder_.Diagnostics())
<< "Module-level conversions are not supported. Conversions should "
"have already been constant-folded by the FoldConstants transform.";
return 0;
}
auto elem_type_of = [](const sem::Type* t) -> const sem::Type* {
if (t->is_scalar()) {
return t;
}
if (auto* v = t->As<sem::Vector>()) {
return v->type();
}
return nullptr;
};
auto result = result_op();
auto result_id = result.to_i();
auto result_type_id = GenerateTypeIfNeeded(to_type);
if (result_type_id == 0) {
return 0;
}
auto val_id = GenerateExpressionWithLoadIfNeeded(from_expr);
if (val_id == 0) {
return 0;
}
auto* from_type = TypeOf(from_expr)->UnwrapRef();
spv::Op op = spv::Op::OpNop;
if ((from_type->Is<sem::I32>() && to_type->Is<sem::F32>()) ||
(from_type->is_signed_integer_vector() && to_type->is_float_vector())) {
op = spv::Op::OpConvertSToF;
} else if ((from_type->Is<sem::U32>() && to_type->Is<sem::F32>()) ||
(from_type->is_unsigned_integer_vector() &&
to_type->is_float_vector())) {
op = spv::Op::OpConvertUToF;
} else if ((from_type->Is<sem::F32>() && to_type->Is<sem::I32>()) ||
(from_type->is_float_vector() &&
to_type->is_signed_integer_vector())) {
op = spv::Op::OpConvertFToS;
} else if ((from_type->Is<sem::F32>() && to_type->Is<sem::U32>()) ||
(from_type->is_float_vector() &&
to_type->is_unsigned_integer_vector())) {
op = spv::Op::OpConvertFToU;
} else if ((from_type->Is<sem::Bool>() && to_type->Is<sem::Bool>()) ||
(from_type->Is<sem::U32>() && to_type->Is<sem::U32>()) ||
(from_type->Is<sem::I32>() && to_type->Is<sem::I32>()) ||
(from_type->Is<sem::F32>() && to_type->Is<sem::F32>()) ||
(from_type->Is<sem::Vector>() && (from_type == to_type))) {
return val_id;
} else if ((from_type->Is<sem::I32>() && to_type->Is<sem::U32>()) ||
(from_type->Is<sem::U32>() && to_type->Is<sem::I32>()) ||
(from_type->is_signed_integer_vector() &&
to_type->is_unsigned_integer_vector()) ||
(from_type->is_unsigned_integer_vector() &&
to_type->is_integer_scalar_or_vector())) {
op = spv::Op::OpBitcast;
} else if ((from_type->is_numeric_scalar() && to_type->Is<sem::Bool>()) ||
(from_type->is_numeric_vector() && to_type->is_bool_vector())) {
// Convert scalar (vector) to bool (vector)
// Return the result of comparing from_expr with zero
uint32_t zero = GenerateConstantNullIfNeeded(from_type);
const auto* from_elem_type = elem_type_of(from_type);
op = from_elem_type->is_integer_scalar() ? spv::Op::OpINotEqual
: spv::Op::OpFUnordNotEqual;
if (!push_function_inst(
op, {Operand::Int(result_type_id), Operand::Int(result_id),
Operand::Int(val_id), Operand::Int(zero)})) {
return 0;
}
return result_id;
} else if (from_type->is_bool_scalar_or_vector() &&
to_type->is_numeric_scalar_or_vector()) {
// Convert bool scalar/vector to numeric scalar/vector.
// Use the bool to select between 1 (if true) and 0 (if false).
const auto* to_elem_type = elem_type_of(to_type);
uint32_t one_id;
uint32_t zero_id;
if (to_elem_type->Is<sem::F32>()) {
ast::FloatLiteralExpression one(ProgramID(), Source{}, 1.0f);
ast::FloatLiteralExpression zero(ProgramID(), Source{}, 0.0f);
one_id = GenerateLiteralIfNeeded(nullptr, &one);
zero_id = GenerateLiteralIfNeeded(nullptr, &zero);
} else if (to_elem_type->Is<sem::U32>()) {
ast::UintLiteralExpression one(ProgramID(), Source{}, 1);
ast::UintLiteralExpression zero(ProgramID(), Source{}, 0);
one_id = GenerateLiteralIfNeeded(nullptr, &one);
zero_id = GenerateLiteralIfNeeded(nullptr, &zero);
} else if (to_elem_type->Is<sem::I32>()) {
ast::SintLiteralExpression one(ProgramID(), Source{}, 1);
ast::SintLiteralExpression zero(ProgramID(), Source{}, 0);
one_id = GenerateLiteralIfNeeded(nullptr, &one);
zero_id = GenerateLiteralIfNeeded(nullptr, &zero);
} else {
error_ = "invalid destination type for bool conversion";
return false;
}
if (auto* to_vec = to_type->As<sem::Vector>()) {
// Splat the scalars into vectors.
one_id = GenerateConstantVectorSplatIfNeeded(to_vec, one_id);
zero_id = GenerateConstantVectorSplatIfNeeded(to_vec, zero_id);
}
if (!one_id || !zero_id) {
return false;
}
op = spv::Op::OpSelect;
if (!push_function_inst(
op, {Operand::Int(result_type_id), Operand::Int(result_id),
Operand::Int(val_id), Operand::Int(one_id),
Operand::Int(zero_id)})) {
return 0;
}
return result_id;
} else {
TINT_ICE(Writer, builder_.Diagnostics()) << "Invalid from_type";
}
if (op == spv::Op::OpNop) {
error_ = "unable to determine conversion type for cast, from: " +
from_type->type_name() + " to: " + to_type->type_name();
return 0;
}
if (!push_function_inst(
op, {Operand::Int(result_type_id), result, Operand::Int(val_id)})) {
return 0;
}
return result_id;
}
uint32_t Builder::GenerateLiteralIfNeeded(const ast::Variable* var,
const ast::LiteralExpression* lit) {
ScalarConstant constant;
auto* global = builder_.Sem().Get<sem::GlobalVariable>(var);
if (global && global->IsOverridable()) {
constant.is_spec_op = true;
constant.constant_id = global->ConstantId();
}
Switch(
lit,
[&](const ast::BoolLiteralExpression* l) {
constant.kind = ScalarConstant::Kind::kBool;
constant.value.b = l->value;
},
[&](const ast::SintLiteralExpression* sl) {
constant.kind = ScalarConstant::Kind::kI32;
constant.value.i32 = sl->value;
},
[&](const ast::UintLiteralExpression* ul) {
constant.kind = ScalarConstant::Kind::kU32;
constant.value.u32 = ul->value;
},
[&](const ast::FloatLiteralExpression* fl) {
constant.kind = ScalarConstant::Kind::kF32;
constant.value.f32 = fl->value;
},
[&](Default) { error_ = "unknown literal type"; });
if (!error_.empty()) {
return false;
}
return GenerateConstantIfNeeded(constant);
}
uint32_t Builder::GenerateConstantIfNeeded(const ScalarConstant& constant) {
auto it = const_to_id_.find(constant);
if (it != const_to_id_.end()) {
return it->second;
}
uint32_t type_id = 0;
switch (constant.kind) {
case ScalarConstant::Kind::kU32: {
type_id = GenerateTypeIfNeeded(builder_.create<sem::U32>());
break;
}
case ScalarConstant::Kind::kI32: {
type_id = GenerateTypeIfNeeded(builder_.create<sem::I32>());
break;
}
case ScalarConstant::Kind::kF32: {
type_id = GenerateTypeIfNeeded(builder_.create<sem::F32>());
break;
}
case ScalarConstant::Kind::kBool: {
type_id = GenerateTypeIfNeeded(builder_.create<sem::Bool>());
break;
}
}
if (type_id == 0) {
return 0;
}
auto result = result_op();
auto result_id = result.to_i();
if (constant.is_spec_op) {
push_annot(spv::Op::OpDecorate,
{Operand::Int(result_id), Operand::Int(SpvDecorationSpecId),
Operand::Int(constant.constant_id)});
}
switch (constant.kind) {
case ScalarConstant::Kind::kU32: {
push_type(
constant.is_spec_op ? spv::Op::OpSpecConstant : spv::Op::OpConstant,
{Operand::Int(type_id), result, Operand::Int(constant.value.u32)});
break;
}
case ScalarConstant::Kind::kI32: {
push_type(
constant.is_spec_op ? spv::Op::OpSpecConstant : spv::Op::OpConstant,
{Operand::Int(type_id), result, Operand::Int(constant.value.i32)});
break;
}
case ScalarConstant::Kind::kF32: {
push_type(
constant.is_spec_op ? spv::Op::OpSpecConstant : spv::Op::OpConstant,
{Operand::Int(type_id), result, Operand::Float(constant.value.f32)});
break;
}
case ScalarConstant::Kind::kBool: {
if (constant.value.b) {
push_type(constant.is_spec_op ? spv::Op::OpSpecConstantTrue
: spv::Op::OpConstantTrue,
{Operand::Int(type_id), result});
} else {
push_type(constant.is_spec_op ? spv::Op::OpSpecConstantFalse
: spv::Op::OpConstantFalse,
{Operand::Int(type_id), result});
}
break;
}
}
const_to_id_[constant] = result_id;
return result_id;
}
uint32_t Builder::GenerateConstantNullIfNeeded(const sem::Type* type) {
auto type_id = GenerateTypeIfNeeded(type);
if (type_id == 0) {
return 0;
}
auto name = type->type_name();
auto it = const_null_to_id_.find(name);
if (it != const_null_to_id_.end()) {
return it->second;
}
auto result = result_op();
auto result_id = result.to_i();
push_type(spv::Op::OpConstantNull, {Operand::Int(type_id), result});
const_null_to_id_[name] = result_id;
return result_id;
}
uint32_t Builder::GenerateConstantVectorSplatIfNeeded(const sem::Vector* type,
uint32_t value_id) {
auto type_id = GenerateTypeIfNeeded(type);
if (type_id == 0 || value_id == 0) {
return 0;
}
uint64_t key = (static_cast<uint64_t>(type->Width()) << 32) + value_id;
return utils::GetOrCreate(const_splat_to_id_, key, [&] {
auto result = result_op();
auto result_id = result.to_i();
OperandList ops;
ops.push_back(Operand::Int(type_id));
ops.push_back(result);
for (uint32_t i = 0; i < type->Width(); i++) {
ops.push_back(Operand::Int(value_id));
}
push_type(spv::Op::OpConstantComposite, ops);
const_splat_to_id_[key] = result_id;
return result_id;
});
}
uint32_t Builder::GenerateShortCircuitBinaryExpression(
const ast::BinaryExpression* expr) {
auto lhs_id = GenerateExpressionWithLoadIfNeeded(expr->lhs);
if (lhs_id == 0) {
return false;
}
// Get the ID of the basic block where control flow will diverge. It's the
// last basic block generated for the left-hand-side of the operator.
auto original_label_id = current_label_id_;
auto type_id = GenerateTypeIfNeeded(TypeOf(expr));
if (type_id == 0) {
return 0;
}
auto merge_block = result_op();
auto merge_block_id = merge_block.to_i();
auto block = result_op();
auto block_id = block.to_i();
auto true_block_id = block_id;
auto false_block_id = merge_block_id;
// For a logical or we want to only check the RHS if the LHS is failed.
if (expr->IsLogicalOr()) {
std::swap(true_block_id, false_block_id);
}
if (!push_function_inst(spv::Op::OpSelectionMerge,
{Operand::Int(merge_block_id),
Operand::Int(SpvSelectionControlMaskNone)})) {
return 0;
}
if (!push_function_inst(spv::Op::OpBranchConditional,
{Operand::Int(lhs_id), Operand::Int(true_block_id),
Operand::Int(false_block_id)})) {
return 0;
}
// Output block to check the RHS
if (!GenerateLabel(block_id)) {
return 0;
}
auto rhs_id = GenerateExpressionWithLoadIfNeeded(expr->rhs);
if (rhs_id == 0) {
return 0;
}
// Get the block ID of the last basic block generated for the right-hand-side
// expression. That block will be an immediate predecessor to the merge block.
auto rhs_block_id = current_label_id_;
if (!push_function_inst(spv::Op::OpBranch, {Operand::Int(merge_block_id)})) {
return 0;
}
// Output the merge block
if (!GenerateLabel(merge_block_id)) {
return 0;
}
auto result = result_op();
auto result_id = result.to_i();
if (!push_function_inst(spv::Op::OpPhi,
{Operand::Int(type_id), result, Operand::Int(lhs_id),
Operand::Int(original_label_id),
Operand::Int(rhs_id), Operand::Int(rhs_block_id)})) {
return 0;
}
return result_id;
}
uint32_t Builder::GenerateSplat(uint32_t scalar_id, const sem::Type* vec_type) {
// Create a new vector to splat scalar into
auto splat_vector = result_op();
auto* splat_vector_type = builder_.create<sem::Pointer>(
vec_type, ast::StorageClass::kFunction, ast::Access::kReadWrite);
push_function_var(
{Operand::Int(GenerateTypeIfNeeded(splat_vector_type)), splat_vector,
Operand::Int(ConvertStorageClass(ast::StorageClass::kFunction)),
Operand::Int(GenerateConstantNullIfNeeded(vec_type))});
// Splat scalar into vector
auto splat_result = result_op();
OperandList ops;
ops.push_back(Operand::Int(GenerateTypeIfNeeded(vec_type)));
ops.push_back(splat_result);
for (size_t i = 0; i < vec_type->As<sem::Vector>()->Width(); ++i) {
ops.push_back(Operand::Int(scalar_id));
}
if (!push_function_inst(spv::Op::OpCompositeConstruct, ops)) {
return 0;
}
return splat_result.to_i();
}
uint32_t Builder::GenerateMatrixAddOrSub(uint32_t lhs_id,
uint32_t rhs_id,
const sem::Matrix* type,
spv::Op op) {
// Example addition of two matrices:
// %31 = OpLoad %mat3v4float %m34
// %32 = OpLoad %mat3v4float %m34
// %33 = OpCompositeExtract %v4float %31 0
// %34 = OpCompositeExtract %v4float %32 0
// %35 = OpFAdd %v4float %33 %34
// %36 = OpCompositeExtract %v4float %31 1
// %37 = OpCompositeExtract %v4float %32 1
// %38 = OpFAdd %v4float %36 %37
// %39 = OpCompositeExtract %v4float %31 2
// %40 = OpCompositeExtract %v4float %32 2
// %41 = OpFAdd %v4float %39 %40
// %42 = OpCompositeConstruct %mat3v4float %35 %38 %41
auto* column_type = builder_.create<sem::Vector>(type->type(), type->rows());
auto column_type_id = GenerateTypeIfNeeded(column_type);
OperandList ops;
for (uint32_t i = 0; i < type->columns(); ++i) {
// Extract column `i` from lhs mat
auto lhs_column_id = result_op();
if (!push_function_inst(spv::Op::OpCompositeExtract,
{Operand::Int(column_type_id), lhs_column_id,
Operand::Int(lhs_id), Operand::Int(i)})) {
return 0;
}
// Extract column `i` from rhs mat
auto rhs_column_id = result_op();
if (!push_function_inst(spv::Op::OpCompositeExtract,
{Operand::Int(column_type_id), rhs_column_id,
Operand::Int(rhs_id), Operand::Int(i)})) {
return 0;
}
// Add or subtract the two columns
auto result = result_op();
if (!push_function_inst(op, {Operand::Int(column_type_id), result,
lhs_column_id, rhs_column_id})) {
return 0;
}
ops.push_back(result);
}
// Create the result matrix from the added/subtracted column vectors
auto result_mat_id = result_op();
ops.insert(ops.begin(), result_mat_id);
ops.insert(ops.begin(), Operand::Int(GenerateTypeIfNeeded(type)));
if (!push_function_inst(spv::Op::OpCompositeConstruct, ops)) {
return 0;
}
return result_mat_id.to_i();
}
uint32_t Builder::GenerateBinaryExpression(const ast::BinaryExpression* expr) {
// There is special logic for short circuiting operators.
if (expr->IsLogicalAnd() || expr->IsLogicalOr()) {
return GenerateShortCircuitBinaryExpression(expr);
}
auto lhs_id = GenerateExpressionWithLoadIfNeeded(expr->lhs);
if (lhs_id == 0) {
return 0;
}
auto rhs_id = GenerateExpressionWithLoadIfNeeded(expr->rhs);
if (rhs_id == 0) {
return 0;
}
auto result = result_op();
auto result_id = result.to_i();
auto type_id = GenerateTypeIfNeeded(TypeOf(expr));
if (type_id == 0) {
return 0;
}
// Handle int and float and the vectors of those types. Other types
// should have been rejected by validation.
auto* lhs_type = TypeOf(expr->lhs)->UnwrapRef();
auto* rhs_type = TypeOf(expr->rhs)->UnwrapRef();
// Handle matrix-matrix addition and subtraction
if ((expr->IsAdd() || expr->IsSubtract()) && lhs_type->is_float_matrix() &&
rhs_type->is_float_matrix()) {
auto* lhs_mat = lhs_type->As<sem::Matrix>();
auto* rhs_mat = rhs_type->As<sem::Matrix>();
// This should already have been validated by resolver
if (lhs_mat->rows() != rhs_mat->rows() ||
lhs_mat->columns() != rhs_mat->columns()) {
error_ = "matrices must have same dimensionality for add or subtract";
return 0;
}
return GenerateMatrixAddOrSub(
lhs_id, rhs_id, lhs_mat,
expr->IsAdd() ? spv::Op::OpFAdd : spv::Op::OpFSub);
}
// For vector-scalar arithmetic operations, splat scalar into a vector. We
// skip this for multiply as we can use OpVectorTimesScalar.
const bool is_float_scalar_vector_multiply =
expr->IsMultiply() &&
((lhs_type->is_float_scalar() && rhs_type->is_float_vector()) ||
(lhs_type->is_float_vector() && rhs_type->is_float_scalar()));
if (expr->IsArithmetic() && !is_float_scalar_vector_multiply) {
if (lhs_type->Is<sem::Vector>() && rhs_type->is_numeric_scalar()) {
uint32_t splat_vector_id = GenerateSplat(rhs_id, lhs_type);
if (splat_vector_id == 0) {
return 0;
}
rhs_id = splat_vector_id;
rhs_type = lhs_type;
} else if (lhs_type->is_numeric_scalar() && rhs_type->Is<sem::Vector>()) {
uint32_t splat_vector_id = GenerateSplat(lhs_id, rhs_type);
if (splat_vector_id == 0) {
return 0;
}
lhs_id = splat_vector_id;
lhs_type = rhs_type;
}
}
bool lhs_is_float_or_vec = lhs_type->is_float_scalar_or_vector();
bool lhs_is_bool_or_vec = lhs_type->is_bool_scalar_or_vector();
bool lhs_is_integer_or_vec = lhs_type->is_integer_scalar_or_vector();
bool lhs_is_unsigned = lhs_type->is_unsigned_scalar_or_vector();
spv::Op op = spv::Op::OpNop;
if (expr->IsAnd()) {
if (lhs_is_integer_or_vec) {
op = spv::Op::OpBitwiseAnd;
} else if (lhs_is_bool_or_vec) {
op = spv::Op::OpLogicalAnd;
} else {
error_ = "invalid and expression";
return 0;
}
} else if (expr->IsAdd()) {
op = lhs_is_float_or_vec ? spv::Op::OpFAdd : spv::Op::OpIAdd;
} else if (expr->IsDivide()) {
if (lhs_is_float_or_vec) {
op = spv::Op::OpFDiv;
} else if (lhs_is_unsigned) {
op = spv::Op::OpUDiv;
} else {
op = spv::Op::OpSDiv;
}
} else if (expr->IsEqual()) {
if (lhs_is_float_or_vec) {
op = spv::Op::OpFOrdEqual;
} else if (lhs_is_bool_or_vec) {
op = spv::Op::OpLogicalEqual;
} else if (lhs_is_integer_or_vec) {
op = spv::Op::OpIEqual;
} else {
error_ = "invalid equal expression";
return 0;
}
} else if (expr->IsGreaterThan()) {
if (lhs_is_float_or_vec) {
op = spv::Op::OpFOrdGreaterThan;
} else if (lhs_is_unsigned) {
op = spv::Op::OpUGreaterThan;
} else {
op = spv::Op::OpSGreaterThan;
}
} else if (expr->IsGreaterThanEqual()) {
if (lhs_is_float_or_vec) {
op = spv::Op::OpFOrdGreaterThanEqual;
} else if (lhs_is_unsigned) {
op = spv::Op::OpUGreaterThanEqual;
} else {
op = spv::Op::OpSGreaterThanEqual;
}
} else if (expr->IsLessThan()) {
if (lhs_is_float_or_vec) {
op = spv::Op::OpFOrdLessThan;
} else if (lhs_is_unsigned) {
op = spv::Op::OpULessThan;
} else {
op = spv::Op::OpSLessThan;
}
} else if (expr->IsLessThanEqual()) {
if (lhs_is_float_or_vec) {
op = spv::Op::OpFOrdLessThanEqual;
} else if (lhs_is_unsigned) {
op = spv::Op::OpULessThanEqual;
} else {
op = spv::Op::OpSLessThanEqual;
}
} else if (expr->IsModulo()) {
if (lhs_is_float_or_vec) {
op = spv::Op::OpFRem;
} else if (lhs_is_unsigned) {
op = spv::Op::OpUMod;
} else {
op = spv::Op::OpSMod;
}
} else if (expr->IsMultiply()) {
if (lhs_type->is_integer_scalar_or_vector()) {
// If the left hand side is an integer then this _has_ to be OpIMul as
// there there is no other integer multiplication.
op = spv::Op::OpIMul;
} else if (lhs_type->is_float_scalar() && rhs_type->is_float_scalar()) {
// Float scalars multiply with OpFMul
op = spv::Op::OpFMul;
} else if (lhs_type->is_float_vector() && rhs_type->is_float_vector()) {
// Float vectors must be validated to be the same size and then use OpFMul
op = spv::Op::OpFMul;
} else if (lhs_type->is_float_scalar() && rhs_type->is_float_vector()) {
// Scalar * Vector we need to flip lhs and rhs types
// because OpVectorTimesScalar expects <vector>, <scalar>
std::swap(lhs_id, rhs_id);
op = spv::Op::OpVectorTimesScalar;
} else if (lhs_type->is_float_vector() && rhs_type->is_float_scalar()) {
// float vector * scalar
op = spv::Op::OpVectorTimesScalar;
} else if (lhs_type->is_float_scalar() && rhs_type->is_float_matrix()) {
// Scalar * Matrix we need to flip lhs and rhs types because
// OpMatrixTimesScalar expects <matrix>, <scalar>
std::swap(lhs_id, rhs_id);
op = spv::Op::OpMatrixTimesScalar;
} else if (lhs_type->is_float_matrix() && rhs_type->is_float_scalar()) {
// float matrix * scalar
op = spv::Op::OpMatrixTimesScalar;
} else if (lhs_type->is_float_vector() && rhs_type->is_float_matrix()) {
// float vector * matrix
op = spv::Op::OpVectorTimesMatrix;
} else if (lhs_type->is_float_matrix() && rhs_type->is_float_vector()) {
// float matrix * vector
op = spv::Op::OpMatrixTimesVector;
} else if (lhs_type->is_float_matrix() && rhs_type->is_float_matrix()) {
// float matrix * matrix
op = spv::Op::OpMatrixTimesMatrix;
} else {
error_ = "invalid multiply expression";
return 0;
}
} else if (expr->IsNotEqual()) {
if (lhs_is_float_or_vec) {
op = spv::Op::OpFOrdNotEqual;
} else if (lhs_is_bool_or_vec) {
op = spv::Op::OpLogicalNotEqual;
} else if (lhs_is_integer_or_vec) {
op = spv::Op::OpINotEqual;
} else {
error_ = "invalid not-equal expression";
return 0;
}
} else if (expr->IsOr()) {
if (lhs_is_integer_or_vec) {
op = spv::Op::OpBitwiseOr;
} else if (lhs_is_bool_or_vec) {
op = spv::Op::OpLogicalOr;
} else {
error_ = "invalid and expression";
return 0;
}
} else if (expr->IsShiftLeft()) {
op = spv::Op::OpShiftLeftLogical;
} else if (expr->IsShiftRight() && lhs_type->is_signed_scalar_or_vector()) {
// A shift right with a signed LHS is an arithmetic shift.
op = spv::Op::OpShiftRightArithmetic;
} else if (expr->IsShiftRight()) {
op = spv::Op::OpShiftRightLogical;
} else if (expr->IsSubtract()) {
op = lhs_is_float_or_vec ? spv::Op::OpFSub : spv::Op::OpISub;
} else if (expr->IsXor()) {
op = spv::Op::OpBitwiseXor;
} else {
error_ = "unknown binary expression";
return 0;
}
if (!push_function_inst(op, {Operand::Int(type_id), result,
Operand::Int(lhs_id), Operand::Int(rhs_id)})) {
return 0;
}
return result_id;
}
bool Builder::GenerateBlockStatement(const ast::BlockStatement* stmt) {
scope_stack_.Push();
TINT_DEFER(scope_stack_.Pop());
return GenerateBlockStatementWithoutScoping(stmt);
}
bool Builder::GenerateBlockStatementWithoutScoping(
const ast::BlockStatement* stmt) {
for (auto* block_stmt : stmt->statements) {
if (!GenerateStatement(block_stmt)) {
return false;
}
}
return true;
}
uint32_t Builder::GenerateCallExpression(const ast::CallExpression* expr) {
auto* call = builder_.Sem().Get(expr);
auto* target = call->Target();
return Switch(
target,
[&](const sem::Function* func) {
return GenerateFunctionCall(call, func);
},
[&](const sem::Builtin* builtin) {
return GenerateBuiltinCall(call, builtin);
},
[&](const sem::TypeConversion*) {
return GenerateTypeConstructorOrConversion(call, nullptr);
},
[&](const sem::TypeConstructor*) {
return GenerateTypeConstructorOrConversion(call, nullptr);
},
[&](Default) -> uint32_t {
TINT_ICE(Writer, builder_.Diagnostics())
<< "unhandled call target: " << target->TypeInfo().name;
return 0;
});
}
uint32_t Builder::GenerateFunctionCall(const sem::Call* call,
const sem::Function*) {
auto* expr = call->Declaration();
auto* ident = expr->target.name;
auto type_id = GenerateTypeIfNeeded(call->Type());
if (type_id == 0) {
return 0;
}
auto result = result_op();
auto result_id = result.to_i();
OperandList ops = {Operand::Int(type_id), result};
auto func_id = func_symbol_to_id_[ident->symbol];
if (func_id == 0) {
error_ = "unable to find called function: " +
builder_.Symbols().NameFor(ident->symbol);
return 0;
}
ops.push_back(Operand::Int(func_id));
size_t arg_idx = 0;
for (auto* arg : expr->args) {
auto id = GenerateExpressionWithLoadIfNeeded(arg);
if (id == 0) {
return 0;
}
ops.push_back(Operand::Int(id));
arg_idx++;
}
if (!push_function_inst(spv::Op::OpFunctionCall, std::move(ops))) {
return 0;
}
return result_id;
}
uint32_t Builder::GenerateBuiltinCall(const sem::Call* call,
const sem::Builtin* builtin) {
auto result = result_op();
auto result_id = result.to_i();
auto result_type_id = GenerateTypeIfNeeded(builtin->ReturnType());
if (result_type_id == 0) {
return 0;
}
if (builtin->IsFineDerivative() || builtin->IsCoarseDerivative()) {
push_capability(SpvCapabilityDerivativeControl);
}
if (builtin->IsImageQuery()) {
push_capability(SpvCapabilityImageQuery);
}
if (builtin->IsTexture()) {
if (!GenerateTextureBuiltin(call, builtin, Operand::Int(result_type_id),
result)) {
return 0;
}
return result_id;
}
if (builtin->IsBarrier()) {
if (!GenerateControlBarrierBuiltin(builtin)) {
return 0;
}
return result_id;
}
if (builtin->IsAtomic()) {
if (!GenerateAtomicBuiltin(call, builtin, Operand::Int(result_type_id),
result)) {
return 0;
}
return result_id;
}
// Generates the SPIR-V ID for the expression for the indexed call argument,
// and loads it if necessary. Returns 0 on error.
auto get_arg_as_value_id = [&](size_t i,
bool generate_load = true) -> uint32_t {
auto* arg = call->Arguments()[i];
auto* param = builtin->Parameters()[i];
auto val_id = GenerateExpression(arg->Declaration());
if (val_id == 0) {
return 0;
}
if (generate_load && !param->Type()->Is<sem::Pointer>()) {
val_id = GenerateLoadIfNeeded(arg->Type(), val_id);
}
return val_id;
};
OperandList params = {Operand::Int(result_type_id), result};
spv::Op op = spv::Op::OpNop;
// Pushes the arguments for a GlslStd450 extended instruction, and sets op
// to OpExtInst.
auto glsl_std450 = [&](uint32_t inst_id) {
auto set_id = GetGLSLstd450Import();
params.push_back(Operand::Int(set_id));
params.push_back(Operand::Int(inst_id));
op = spv::Op::OpExtInst;
};
switch (builtin->Type()) {
case BuiltinType::kAny:
if (builtin->Parameters()[0]->Type()->Is<sem::Bool>()) {
// any(v: bool) just resolves to v.
return get_arg_as_value_id(0);
}
op = spv::Op::OpAny;
break;
case BuiltinType::kAll:
if (builtin->Parameters()[0]->Type()->Is<sem::Bool>()) {
// all(v: bool) just resolves to v.
return get_arg_as_value_id(0);
}
op = spv::Op::OpAll;
break;
case BuiltinType::kArrayLength: {
auto* address_of =
call->Arguments()[0]->Declaration()->As<ast::UnaryOpExpression>();
if (!address_of || address_of->op != ast::UnaryOp::kAddressOf) {
error_ = "arrayLength() expected pointer to member access, got " +
std::string(address_of->TypeInfo().name);
return 0;
}
auto* array_expr = address_of->expr;
auto* accessor = array_expr->As<ast::MemberAccessorExpression>();
if (!accessor) {
error_ =
"arrayLength() expected pointer to member access, got pointer to " +
std::string(array_expr->TypeInfo().name);
return 0;
}
auto struct_id = GenerateExpression(accessor->structure);
if (struct_id == 0) {
return 0;
}
params.push_back(Operand::Int(struct_id));
auto* type = TypeOf(accessor->structure)->UnwrapRef();
if (!type->Is<sem::Struct>()) {
error_ =
"invalid type (" + type->type_name() + ") for runtime array length";
return 0;
}
// Runtime array must be the last member in the structure
params.push_back(Operand::Int(uint32_t(
type->As<sem::Struct>()->Declaration()->members.size() - 1)));
if (!push_function_inst(spv::Op::OpArrayLength, params)) {
return 0;
}
return result_id;
}
case BuiltinType::kCountOneBits:
op = spv::Op::OpBitCount;
break;
case BuiltinType::kDot: {
op = spv::Op::OpDot;
auto* vec_ty = builtin->Parameters()[0]->Type()->As<sem::Vector>();
if (vec_ty->type()->is_integer_scalar()) {
// TODO(crbug.com/tint/1267): OpDot requires floating-point types, but
// WGSL also supports integer types. SPV_KHR_integer_dot_product adds
// support for integer vectors. Use it if it is available.
auto el_ty = Operand::Int(GenerateTypeIfNeeded(vec_ty->type()));
auto vec_a = Operand::Int(get_arg_as_value_id(0));
auto vec_b = Operand::Int(get_arg_as_value_id(1));
if (vec_a.to_i() == 0 || vec_b.to_i() == 0) {
return 0;
}
auto sum = Operand::Int(0);
for (uint32_t i = 0; i < vec_ty->Width(); i++) {
auto a = result_op();
auto b = result_op();
auto mul = result_op();
if (!push_function_inst(spv::Op::OpCompositeExtract,
{el_ty, a, vec_a, Operand::Int(i)}) ||
!push_function_inst(spv::Op::OpCompositeExtract,
{el_ty, b, vec_b, Operand::Int(i)}) ||
!push_function_inst(spv::Op::OpIMul, {el_ty, mul, a, b})) {
return 0;
}
if (i == 0) {
sum = mul;
} else {
auto prev_sum = sum;
auto is_last_el = i == (vec_ty->Width() - 1);
sum = is_last_el ? Operand::Int(result_id) : result_op();
if (!push_function_inst(spv::Op::OpIAdd,
{el_ty, sum, prev_sum, mul})) {
return 0;
}
}
}
return result_id;
}
break;
}
case BuiltinType::kDpdx:
op = spv::Op::OpDPdx;
break;
case BuiltinType::kDpdxCoarse:
op = spv::Op::OpDPdxCoarse;
break;
case BuiltinType::kDpdxFine:
op = spv::Op::OpDPdxFine;
break;
case BuiltinType::kDpdy:
op = spv::Op::OpDPdy;
break;
case BuiltinType::kDpdyCoarse:
op = spv::Op::OpDPdyCoarse;
break;
case BuiltinType::kDpdyFine:
op = spv::Op::OpDPdyFine;
break;
case BuiltinType::kFwidth:
op = spv::Op::OpFwidth;
break;
case BuiltinType::kFwidthCoarse:
op = spv::Op::OpFwidthCoarse;
break;
case BuiltinType::kFwidthFine:
op = spv::Op::OpFwidthFine;
break;
case BuiltinType::kIsInf:
op = spv::Op::OpIsInf;
break;
case BuiltinType::kIsNan:
op = spv::Op::OpIsNan;
break;
case BuiltinType::kIsFinite: {
// Implemented as: not(IsInf or IsNan)
auto val_id = get_arg_as_value_id(0);
if (!val_id) {
return 0;
}
auto inf_result = result_op();
auto nan_result = result_op();
auto or_result = result_op();
if (push_function_inst(spv::Op::OpIsInf,
{Operand::Int(result_type_id), inf_result,
Operand::Int(val_id)}) &&
push_function_inst(spv::Op::OpIsNan,
{Operand::Int(result_type_id), nan_result,
Operand::Int(val_id)}) &&
push_function_inst(spv::Op::OpLogicalOr,
{Operand::Int(result_type_id), or_result,
Operand::Int(inf_result.to_i()),
Operand::Int(nan_result.to_i())}) &&
push_function_inst(spv::Op::OpLogicalNot,
{Operand::Int(result_type_id), result,
Operand::Int(or_result.to_i())})) {
return result_id;
}
return 0;
}
case BuiltinType::kIsNormal: {
// A normal number is finite, non-zero, and not subnormal.
// Its exponent is neither of the extreme possible values.
// Implemented as:
// exponent_bits = bitcast<u32>(f);
// clamped = uclamp(1,254,exponent_bits);
// result = (clamped == exponent_bits);
//
auto val_id = get_arg_as_value_id(0);
if (!val_id) {
return 0;
}
// These parameters are valid for IEEE 754 binary32
const uint32_t kExponentMask = 0x7f80000;
const uint32_t kMinNormalExponent = 0x0080000;
const uint32_t kMaxNormalExponent = 0x7f00000;
auto set_id = GetGLSLstd450Import();
auto* u32 = builder_.create<sem::U32>();
auto unsigned_id = GenerateTypeIfNeeded(u32);
auto exponent_mask_id =
GenerateConstantIfNeeded(ScalarConstant::U32(kExponentMask));
auto min_exponent_id =
GenerateConstantIfNeeded(ScalarConstant::U32(kMinNormalExponent));
auto max_exponent_id =
GenerateConstantIfNeeded(ScalarConstant::U32(kMaxNormalExponent));
if (auto* fvec_ty = builtin->ReturnType()->As<sem::Vector>()) {
// In the vector case, update the unsigned type to a vector type of the
// same size, and create vector constants by replicating the scalars.
// I expect backend compilers to fold these into unique constants, so
// there is no loss of efficiency.
auto* uvec_ty = builder_.create<sem::Vector>(u32, fvec_ty->Width());
unsigned_id = GenerateTypeIfNeeded(uvec_ty);
auto splat = [&](uint32_t scalar_id) -> uint32_t {
auto splat_result = result_op();
OperandList splat_params{Operand::Int(unsigned_id), splat_result};
for (size_t i = 0; i < fvec_ty->Width(); i++) {
splat_params.emplace_back(Operand::Int(scalar_id));
}
if (!push_function_inst(spv::Op::OpCompositeConstruct,
std::move(splat_params))) {
return 0;
}
return splat_result.to_i();
};
exponent_mask_id = splat(exponent_mask_id);
min_exponent_id = splat(min_exponent_id);
max_exponent_id = splat(max_exponent_id);
}
auto cast_result = result_op();
auto exponent_bits_result = result_op();
auto clamp_result = result_op();
if (set_id && unsigned_id && exponent_mask_id && min_exponent_id &&
max_exponent_id &&
push_function_inst(
spv::Op::OpBitcast,
{Operand::Int(unsigned_id), cast_result, Operand::Int(val_id)}) &&
push_function_inst(spv::Op::OpBitwiseAnd,
{Operand::Int(unsigned_id), exponent_bits_result,
Operand::Int(cast_result.to_i()),
Operand::Int(exponent_mask_id)}) &&
push_function_inst(
spv::Op::OpExtInst,
{Operand::Int(unsigned_id), clamp_result, Operand::Int(set_id),
Operand::Int(GLSLstd450UClamp),
Operand::Int(exponent_bits_result.to_i()),
Operand::Int(min_exponent_id), Operand::Int(max_exponent_id)}) &&
push_function_inst(spv::Op::OpIEqual,
{Operand::Int(result_type_id), result,
Operand::Int(exponent_bits_result.to_i()),
Operand::Int(clamp_result.to_i())})) {
return result_id;
}
return 0;
}
case BuiltinType::kMix: {
auto std450 = Operand::Int(GetGLSLstd450Import());
auto a_id = get_arg_as_value_id(0);
auto b_id = get_arg_as_value_id(1);
auto f_id = get_arg_as_value_id(2);
if (!a_id || !b_id || !f_id) {
return 0;
}
// If the interpolant is scalar but the objects are vectors, we need to
// splat the interpolant into a vector of the same size.
auto* result_vector_type = builtin->ReturnType()->As<sem::Vector>();
if (result_vector_type && builtin->Parameters()[2]->Type()->is_scalar()) {
f_id = GenerateSplat(f_id, builtin->Parameters()[0]->Type());
if (f_id == 0) {
return 0;
}
}
if (!push_function_inst(spv::Op::OpExtInst,
{Operand::Int(result_type_id), result, std450,
Operand::Int(GLSLstd450FMix), Operand::Int(a_id),
Operand::Int(b_id), Operand::Int(f_id)})) {
return 0;
}
return result_id;
}
case BuiltinType::kReverseBits:
op = spv::Op::OpBitReverse;
break;
case BuiltinType::kSelect: {
// Note: Argument order is different in WGSL and SPIR-V
auto cond_id = get_arg_as_value_id(2);
auto true_id = get_arg_as_value_id(1);
auto false_id = get_arg_as_value_id(0);
if (!cond_id || !true_id || !false_id) {
return 0;
}
// If the condition is scalar but the objects are vectors, we need to
// splat the condition into a vector of the same size.
// TODO(jrprice): If we're targeting SPIR-V 1.4, we don't need to do this.
auto* result_vector_type = builtin->ReturnType()->As<sem::Vector>();
if (result_vector_type && builtin->Parameters()[2]->Type()->is_scalar()) {
auto* bool_vec_ty = builder_.create<sem::Vector>(
builder_.create<sem::Bool>(), result_vector_type->Width());
if (!GenerateTypeIfNeeded(bool_vec_ty)) {
return 0;
}
cond_id = GenerateSplat(cond_id, bool_vec_ty);
if (cond_id == 0) {
return 0;
}
}
if (!push_function_inst(
spv::Op::OpSelect,
{Operand::Int(result_type_id), result, Operand::Int(cond_id),
Operand::Int(true_id), Operand::Int(false_id)})) {
return 0;
}
return result_id;
}
case BuiltinType::kTranspose:
op = spv::Op::OpTranspose;
break;
case BuiltinType::kAbs:
if (builtin->ReturnType()->is_unsigned_scalar_or_vector()) {
// abs() only operates on *signed* integers.
// This is a no-op for unsigned integers.
return get_arg_as_value_id(0);
}
if (builtin->ReturnType()->is_float_scalar_or_vector()) {
glsl_std450(GLSLstd450FAbs);
} else {
glsl_std450(GLSLstd450SAbs);
}
break;
default: {
auto inst_id = builtin_to_glsl_method(builtin);
if (inst_id == 0) {
error_ = "unknown method " + std::string(builtin->str());
return 0;
}
glsl_std450(inst_id);
break;
}
}
if (op == spv::Op::OpNop) {
error_ = "unable to determine operator for: " + std::string(builtin->str());
return 0;
}
for (size_t i = 0; i < call->Arguments().size(); i++) {
if (auto val_id = get_arg_as_value_id(i)) {
params.emplace_back(Operand::Int(val_id));
} else {
return 0;
}
}
if (!push_function_inst(op, params)) {
return 0;
}
return result_id;
}
bool Builder::GenerateTextureBuiltin(const sem::Call* call,
const sem::Builtin* builtin,
Operand result_type,
Operand result_id) {
using Usage = sem::ParameterUsage;
auto& signature = builtin->Signature();
auto& arguments = call->Arguments();
// Generates the given expression, returning the operand ID
auto gen = [&](const sem::Expression* expr) {
const auto val_id = GenerateExpressionWithLoadIfNeeded(expr);
return Operand::Int(val_id);
};
// Returns the argument with the given usage
auto arg = [&](Usage usage) {
int idx = signature.IndexOf(usage);
return (idx >= 0) ? arguments[idx] : nullptr;
};
// Generates the argument with the given usage, returning the operand ID
auto gen_arg = [&](Usage usage) {
auto* argument = arg(usage);
if (!argument) {
TINT_ICE(Writer, builder_.Diagnostics())
<< "missing argument " << static_cast<int>(usage);
}
return gen(argument);
};
auto* texture = arg(Usage::kTexture);
if (!texture) {
TINT_ICE(Writer, builder_.Diagnostics()) << "missing texture argument";
}
auto* texture_type = texture->Type()->UnwrapRef()->As<sem::Texture>();
auto op = spv::Op::OpNop;
// Custom function to call after the texture-builtin op has been generated.
std::function<bool()> post_emission = [] { return true; };
// Populate the spirv_params with common parameters
OperandList spirv_params;
spirv_params.reserve(8); // Enough to fit most parameter lists
// Extra image operands, appended to spirv_params.
struct ImageOperand {
SpvImageOperandsMask mask;
Operand operand;
};
std::vector<ImageOperand> image_operands;
image_operands.reserve(4); // Enough to fit most parameter lists
// Appends `result_type` and `result_id` to `spirv_params`
auto append_result_type_and_id_to_spirv_params = [&]() {
spirv_params.emplace_back(std::move(result_type));
spirv_params.emplace_back(std::move(result_id));
};
// Appends a result type and id to `spirv_params`, possibly adding a
// post_emission step.
//
// If the texture is a depth texture, then this function wraps the result of
// the op with a OpCompositeExtract to evaluate to the first element of the
// returned vector. This is done as the WGSL texture reading functions for
// depths return a single float scalar instead of a vector.
//
// If the texture is not a depth texture, then this function simply delegates
// to calling append_result_type_and_id_to_spirv_params().
auto append_result_type_and_id_to_spirv_params_for_read = [&]() {
if (texture_type
->IsAnyOf<sem::DepthTexture, sem::DepthMultisampledTexture>()) {
auto* f32 = builder_.create<sem::F32>();
auto* spirv_result_type = builder_.create<sem::Vector>(f32, 4);
auto spirv_result = result_op();
post_emission = [=] {
return push_function_inst(
spv::Op::OpCompositeExtract,
{result_type, result_id, spirv_result, Operand::Int(0)});
};
auto spirv_result_type_id = GenerateTypeIfNeeded(spirv_result_type);
if (spirv_result_type_id == 0) {
return false;
}
spirv_params.emplace_back(Operand::Int(spirv_result_type_id));
spirv_params.emplace_back(spirv_result);
return true;
}
append_result_type_and_id_to_spirv_params();
return true;
};
// Appends a result type and id to `spirv_params`, by first swizzling the
// result of the op with `swizzle`.
auto append_result_type_and_id_to_spirv_params_swizzled =
[&](uint32_t spirv_result_width, std::vector<uint32_t> swizzle) {
if (swizzle.empty()) {
append_result_type_and_id_to_spirv_params();
} else {
// Assign post_emission to swizzle the result of the call to
// OpImageQuerySize[Lod].
auto* element_type = ElementTypeOf(call->Type());
auto spirv_result = result_op();
auto* spirv_result_type =
builder_.create<sem::Vector>(element_type, spirv_result_width);
if (swizzle.size() > 1) {
post_emission = [=] {
OperandList operands{
result_type,
result_id,
spirv_result,
spirv_result,
};
for (auto idx : swizzle) {
operands.emplace_back(Operand::Int(idx));
}
return push_function_inst(spv::Op::OpVectorShuffle, operands);
};
} else {
post_emission = [=] {
return push_function_inst(spv::Op::OpCompositeExtract,
{result_type, result_id, spirv_result,
Operand::Int(swizzle[0])});
};
}
auto spirv_result_type_id = GenerateTypeIfNeeded(spirv_result_type);
if (spirv_result_type_id == 0) {
return false;
}
spirv_params.emplace_back(Operand::Int(spirv_result_type_id));
spirv_params.emplace_back(spirv_result);
}
return true;
};
auto append_coords_to_spirv_params = [&]() -> bool {
if (auto* array_index = arg(Usage::kArrayIndex)) {
// Array index needs to be appended to the coordinates.
auto* packed = AppendVector(&builder_, arg(Usage::kCoords)->Declaration(),
array_index->Declaration());
auto param = GenerateExpression(packed->Declaration());
if (param == 0) {
return false;
}
spirv_params.emplace_back(Operand::Int(param));
} else {
spirv_params.emplace_back(gen_arg(Usage::kCoords)); // coordinates
}
return true;
};
auto append_image_and_coords_to_spirv_params = [&]() -> bool {
auto sampler_param = gen_arg(Usage::kSampler);
auto texture_param = gen_arg(Usage::kTexture);
auto sampled_image =
GenerateSampledImage(texture_type, texture_param, sampler_param);
// Populate the spirv_params with the common parameters
spirv_params.emplace_back(Operand::Int(sampled_image)); // sampled image
return append_coords_to_spirv_params();
};
switch (builtin->Type()) {
case BuiltinType::kTextureDimensions: {
// Number of returned elements from OpImageQuerySize[Lod] may not match
// those of textureDimensions().
// This might be due to an extra vector scalar describing the number of
// array elements or textureDimensions() returning a vec3 for cubes
// when only width / height is returned by OpImageQuerySize[Lod]
// (see https://github.com/gpuweb/gpuweb/issues/1345).
// Handle these mismatches by swizzling the returned vector.
std::vector<uint32_t> swizzle;
uint32_t spirv_dims = 0;
switch (texture_type->dim()) {
case ast::TextureDimension::kNone:
error_ = "texture dimension is kNone";
return false;
case ast::TextureDimension::k1d:
case ast::TextureDimension::k2d:
case ast::TextureDimension::k3d:
case ast::TextureDimension::kCube:
break; // No swizzle needed
case ast::TextureDimension::kCubeArray:
case ast::TextureDimension::k2dArray:
swizzle = {0, 1}; // Strip array index
spirv_dims = 3; // [width, height, array_count]
break;
}
if (!append_result_type_and_id_to_spirv_params_swizzled(spirv_dims,
swizzle)) {
return false;
}
spirv_params.emplace_back(gen_arg(Usage::kTexture));
if (texture_type->IsAnyOf<sem::MultisampledTexture, //
sem::DepthMultisampledTexture, //
sem::StorageTexture>()) {
op = spv::Op::OpImageQuerySize;
} else if (auto* level = arg(Usage::kLevel)) {
op = spv::Op::OpImageQuerySizeLod;
spirv_params.emplace_back(gen(level));
} else {
ast::SintLiteralExpression i32_0(ProgramID(), Source{}, 0);
op = spv::Op::OpImageQuerySizeLod;
spirv_params.emplace_back(
Operand::Int(GenerateLiteralIfNeeded(nullptr, &i32_0)));
}
break;
}
case BuiltinType::kTextureNumLayers: {
uint32_t spirv_dims = 0;
switch (texture_type->dim()) {
default:
error_ = "texture is not arrayed";
return false;
case ast::TextureDimension::k2dArray:
case ast::TextureDimension::kCubeArray:
spirv_dims = 3;
break;
}
// OpImageQuerySize[Lod] packs the array count as the last element of the
// returned vector. Extract this.
if (!append_result_type_and_id_to_spirv_params_swizzled(
spirv_dims, {spirv_dims - 1})) {
return false;
}
spirv_params.emplace_back(gen_arg(Usage::kTexture));
if (texture_type->Is<sem::MultisampledTexture>() ||
texture_type->Is<sem::StorageTexture>()) {
op = spv::Op::OpImageQuerySize;
} else {
ast::SintLiteralExpression i32_0(ProgramID(), Source{}, 0);
op = spv::Op::OpImageQuerySizeLod;
spirv_params.emplace_back(
Operand::Int(GenerateLiteralIfNeeded(nullptr, &i32_0)));
}
break;
}
case BuiltinType::kTextureNumLevels: {
op = spv::Op::OpImageQueryLevels;
append_result_type_and_id_to_spirv_params();
spirv_params.emplace_back(gen_arg(Usage::kTexture));
break;
}
case BuiltinType::kTextureNumSamples: {
op = spv::Op::OpImageQuerySamples;
append_result_type_and_id_to_spirv_params();
spirv_params.emplace_back(gen_arg(Usage::kTexture));
break;
}
case BuiltinType::kTextureLoad: {
op = texture_type->Is<sem::StorageTexture>() ? spv::Op::OpImageRead
: spv::Op::OpImageFetch;
append_result_type_and_id_to_spirv_params_for_read();
spirv_params.emplace_back(gen_arg(Usage::kTexture));
if (!append_coords_to_spirv_params()) {
return false;
}
if (auto* level = arg(Usage::kLevel)) {
image_operands.emplace_back(
ImageOperand{SpvImageOperandsLodMask, gen(level)});
}
if (auto* sample_index = arg(Usage::kSampleIndex)) {
image_operands.emplace_back(
ImageOperand{SpvImageOperandsSampleMask, gen(sample_index)});
}
break;
}
case BuiltinType::kTextureStore: {
op = spv::Op::OpImageWrite;
spirv_params.emplace_back(gen_arg(Usage::kTexture));
if (!append_coords_to_spirv_params()) {
return false;
}
spirv_params.emplace_back(gen_arg(Usage::kValue));
break;
}
case BuiltinType::kTextureGather: {
op = spv::Op::OpImageGather;
append_result_type_and_id_to_spirv_params();
if (!append_image_and_coords_to_spirv_params()) {
return false;
}
if (signature.IndexOf(Usage::kComponent) < 0) {
spirv_params.emplace_back(
Operand::Int(GenerateConstantIfNeeded(ScalarConstant::I32(0))));
} else {
spirv_params.emplace_back(gen_arg(Usage::kComponent));
}
break;
}
case BuiltinType::kTextureGatherCompare: {
op = spv::Op::OpImageDrefGather;
append_result_type_and_id_to_spirv_params();
if (!append_image_and_coords_to_spirv_params()) {
return false;
}
spirv_params.emplace_back(gen_arg(Usage::kDepthRef));
break;
}
case BuiltinType::kTextureSample: {
op = spv::Op::OpImageSampleImplicitLod;
append_result_type_and_id_to_spirv_params_for_read();
if (!append_image_and_coords_to_spirv_params()) {
return false;
}
break;
}
case BuiltinType::kTextureSampleBias: {
op = spv::Op::OpImageSampleImplicitLod;
append_result_type_and_id_to_spirv_params_for_read();
if (!append_image_and_coords_to_spirv_params()) {
return false;
}
image_operands.emplace_back(
ImageOperand{SpvImageOperandsBiasMask, gen_arg(Usage::kBias)});
break;
}
case BuiltinType::kTextureSampleLevel: {
op = spv::Op::OpImageSampleExplicitLod;
append_result_type_and_id_to_spirv_params_for_read();
if (!append_image_and_coords_to_spirv_params()) {
return false;
}
auto level = Operand::Int(0);
if (arg(Usage::kLevel)->Type()->UnwrapRef()->Is<sem::I32>()) {
// Depth textures have i32 parameters for the level, but SPIR-V expects
// F32. Cast.
auto f32_type_id = GenerateTypeIfNeeded(builder_.create<sem::F32>());
if (f32_type_id == 0) {
return 0;
}
level = result_op();
if (!push_function_inst(
spv::Op::OpConvertSToF,
{Operand::Int(f32_type_id), level, gen_arg(Usage::kLevel)})) {
return 0;
}
} else {
level = gen_arg(Usage::kLevel);
}
image_operands.emplace_back(ImageOperand{SpvImageOperandsLodMask, level});
break;
}
case BuiltinType::kTextureSampleGrad: {
op = spv::Op::OpImageSampleExplicitLod;
append_result_type_and_id_to_spirv_params_for_read();
if (!append_image_and_coords_to_spirv_params()) {
return false;
}
image_operands.emplace_back(
ImageOperand{SpvImageOperandsGradMask, gen_arg(Usage::kDdx)});
image_operands.emplace_back(
ImageOperand{SpvImageOperandsGradMask, gen_arg(Usage::kDdy)});
break;
}
case BuiltinType::kTextureSampleCompare: {
op = spv::Op::OpImageSampleDrefImplicitLod;
append_result_type_and_id_to_spirv_params();
if (!append_image_and_coords_to_spirv_params()) {
return false;
}
spirv_params.emplace_back(gen_arg(Usage::kDepthRef));
break;
}
case BuiltinType::kTextureSampleCompareLevel: {
op = spv::Op::OpImageSampleDrefExplicitLod;
append_result_type_and_id_to_spirv_params();
if (!append_image_and_coords_to_spirv_params()) {
return false;
}
spirv_params.emplace_back(gen_arg(Usage::kDepthRef));
ast::FloatLiteralExpression float_0(ProgramID(), Source{}, 0.0);
image_operands.emplace_back(ImageOperand{
SpvImageOperandsLodMask,
Operand::Int(GenerateLiteralIfNeeded(nullptr, &float_0))});
break;
}
default:
TINT_UNREACHABLE(Writer, builder_.Diagnostics());
return false;
}
if (auto* offset = arg(Usage::kOffset)) {
image_operands.emplace_back(
ImageOperand{SpvImageOperandsConstOffsetMask, gen(offset)});
}
if (!image_operands.empty()) {
std::sort(image_operands.begin(), image_operands.end(),
[](auto& a, auto& b) { return a.mask < b.mask; });
uint32_t mask = 0;
for (auto& image_operand : image_operands) {
mask |= image_operand.mask;
}
spirv_params.emplace_back(Operand::Int(mask));
for (auto& image_operand : image_operands) {
spirv_params.emplace_back(image_operand.operand);
}
}
if (op == spv::Op::OpNop) {
error_ = "unable to determine operator for: " + std::string(builtin->str());
return false;
}
if (!push_function_inst(op, spirv_params)) {
return false;
}
return post_emission();
}
bool Builder::GenerateControlBarrierBuiltin(const sem::Builtin* builtin) {
auto const op = spv::Op::OpControlBarrier;
uint32_t execution = 0;
uint32_t memory = 0;
uint32_t semantics = 0;
// TODO(crbug.com/tint/661): Combine sequential barriers to a single
// instruction.
if (builtin->Type() == sem::BuiltinType::kWorkgroupBarrier) {
execution = static_cast<uint32_t>(spv::Scope::Workgroup);
memory = static_cast<uint32_t>(spv::Scope::Workgroup);
semantics =
static_cast<uint32_t>(spv::MemorySemanticsMask::AcquireRelease) |
static_cast<uint32_t>(spv::MemorySemanticsMask::WorkgroupMemory);
} else if (builtin->Type() == sem::BuiltinType::kStorageBarrier) {
execution = static_cast<uint32_t>(spv::Scope::Workgroup);
memory = static_cast<uint32_t>(spv::Scope::Workgroup);
semantics =
static_cast<uint32_t>(spv::MemorySemanticsMask::AcquireRelease) |
static_cast<uint32_t>(spv::MemorySemanticsMask::UniformMemory);
} else {
error_ = "unexpected barrier builtin type ";
error_ += sem::str(builtin->Type());
return false;
}
auto execution_id = GenerateConstantIfNeeded(ScalarConstant::U32(execution));
auto memory_id = GenerateConstantIfNeeded(ScalarConstant::U32(memory));
auto semantics_id = GenerateConstantIfNeeded(ScalarConstant::U32(semantics));
if (execution_id == 0 || memory_id == 0 || semantics_id == 0) {
return false;
}
return push_function_inst(op, {
Operand::Int(execution_id),
Operand::Int(memory_id),
Operand::Int(semantics_id),
});
}
bool Builder::GenerateAtomicBuiltin(const sem::Call* call,
const sem::Builtin* builtin,
Operand result_type,
Operand result_id) {
auto is_value_signed = [&] {
return builtin->Parameters()[1]->Type()->Is<sem::I32>();
};
auto storage_class =
builtin->Parameters()[0]->Type()->As<sem::Pointer>()->StorageClass();
uint32_t memory_id = 0;
switch (
builtin->Parameters()[0]->Type()->As<sem::Pointer>()->StorageClass()) {
case ast::StorageClass::kWorkgroup:
memory_id = GenerateConstantIfNeeded(
ScalarConstant::U32(static_cast<uint32_t>(spv::Scope::Workgroup)));
break;
case ast::StorageClass::kStorage:
memory_id = GenerateConstantIfNeeded(
ScalarConstant::U32(static_cast<uint32_t>(spv::Scope::Device)));
break;
default:
TINT_UNREACHABLE(Writer, builder_.Diagnostics())
<< "unhandled atomic storage class " << storage_class;
return false;
}
if (memory_id == 0) {
return false;
}
uint32_t semantics_id = GenerateConstantIfNeeded(ScalarConstant::U32(
static_cast<uint32_t>(spv::MemorySemanticsMask::MaskNone)));
if (semantics_id == 0) {
return false;
}
uint32_t pointer_id = GenerateExpression(call->Arguments()[0]->Declaration());
if (pointer_id == 0) {
return false;
}
uint32_t value_id = 0;
if (call->Arguments().size() > 1) {
value_id = GenerateExpressionWithLoadIfNeeded(call->Arguments().back());
if (value_id == 0) {
return false;
}
}
Operand pointer = Operand::Int(pointer_id);
Operand value = Operand::Int(value_id);
Operand memory = Operand::Int(memory_id);
Operand semantics = Operand::Int(semantics_id);
switch (builtin->Type()) {
case sem::BuiltinType::kAtomicLoad:
return push_function_inst(spv::Op::OpAtomicLoad, {
result_type,
result_id,
pointer,
memory,
semantics,
});
case sem::BuiltinType::kAtomicStore:
return push_function_inst(spv::Op::OpAtomicStore, {
pointer,
memory,
semantics,
value,
});
case sem::BuiltinType::kAtomicAdd:
return push_function_inst(spv::Op::OpAtomicIAdd, {
result_type,
result_id,
pointer,
memory,
semantics,
value,
});
case sem::BuiltinType::kAtomicSub:
return push_function_inst(spv::Op::OpAtomicISub, {
result_type,
result_id,
pointer,
memory,
semantics,
value,
});
case sem::BuiltinType::kAtomicMax:
return push_function_inst(
is_value_signed() ? spv::Op::OpAtomicSMax : spv::Op::OpAtomicUMax,
{
result_type,
result_id,
pointer,
memory,
semantics,
value,
});
case sem::BuiltinType::kAtomicMin:
return push_function_inst(
is_value_signed() ? spv::Op::OpAtomicSMin : spv::Op::OpAtomicUMin,
{
result_type,
result_id,
pointer,
memory,
semantics,
value,
});
case sem::BuiltinType::kAtomicAnd:
return push_function_inst(spv::Op::OpAtomicAnd, {
result_type,
result_id,
pointer,
memory,
semantics,
value,
});
case sem::BuiltinType::kAtomicOr:
return push_function_inst(spv::Op::OpAtomicOr, {
result_type,
result_id,
pointer,
memory,
semantics,
value,
});
case sem::BuiltinType::kAtomicXor:
return push_function_inst(spv::Op::OpAtomicXor, {
result_type,
result_id,
pointer,
memory,
semantics,
value,
});
case sem::BuiltinType::kAtomicExchange:
return push_function_inst(spv::Op::OpAtomicExchange, {
result_type,
result_id,
pointer,
memory,
semantics,
value,
});
case sem::BuiltinType::kAtomicCompareExchangeWeak: {
auto comparator = GenerateExpression(call->Arguments()[1]->Declaration());
if (comparator == 0) {
return false;
}
auto* value_sem_type = TypeOf(call->Arguments()[2]->Declaration());
auto value_type = GenerateTypeIfNeeded(value_sem_type);
if (value_type == 0) {
return false;
}
auto* bool_sem_ty = builder_.create<sem::Bool>();
auto bool_type = GenerateTypeIfNeeded(bool_sem_ty);
if (bool_type == 0) {
return false;
}
// original_value := OpAtomicCompareExchange(pointer, memory, semantics,
// semantics, value, comparator)
auto original_value = result_op();
if (!push_function_inst(spv::Op::OpAtomicCompareExchange,
{
Operand::Int(value_type),
original_value,
pointer,
memory,
semantics,
semantics,
value,
Operand::Int(comparator),
})) {
return false;
}
// values_equal := original_value == value
auto values_equal = result_op();
if (!push_function_inst(spv::Op::OpIEqual, {
Operand::Int(bool_type),
values_equal,
original_value,
value,
})) {
return false;
}
// zero := T(0)
// one := T(1)
uint32_t zero = 0;
uint32_t one = 0;
if (value_sem_type->Is<sem::I32>()) {
zero = GenerateConstantIfNeeded(ScalarConstant::I32(0u));
one = GenerateConstantIfNeeded(ScalarConstant::I32(1u));
} else if (value_sem_type->Is<sem::U32>()) {
zero = GenerateConstantIfNeeded(ScalarConstant::U32(0u));
one = GenerateConstantIfNeeded(ScalarConstant::U32(1u));
} else {
TINT_UNREACHABLE(Writer, builder_.Diagnostics())
<< "unsupported atomic type " << value_sem_type->TypeInfo().name;
}
if (zero == 0 || one == 0) {
return false;
}
// xchg_success := values_equal ? one : zero
auto xchg_success = result_op();
if (!push_function_inst(spv::Op::OpSelect, {
Operand::Int(value_type),
xchg_success,
values_equal,
Operand::Int(one),
Operand::Int(zero),
})) {
return false;
}
// result := vec2<T>(original_value, xchg_success)
return push_function_inst(spv::Op::OpCompositeConstruct,
{
result_type,
result_id,
original_value,
xchg_success,
});
}
default:
TINT_UNREACHABLE(Writer, builder_.Diagnostics())
<< "unhandled atomic builtin " << builtin->Type();
return false;
}
}
uint32_t Builder::GenerateSampledImage(const sem::Type* texture_type,
Operand texture_operand,
Operand sampler_operand) {
uint32_t sampled_image_type_id = 0;
auto val = texture_type_name_to_sampled_image_type_id_.find(
texture_type->type_name());
if (val != texture_type_name_to_sampled_image_type_id_.end()) {
// The sampled image type is already created.
sampled_image_type_id = val->second;
} else {
// We need to create the sampled image type and cache the result.
auto sampled_image_type = result_op();
sampled_image_type_id = sampled_image_type.to_i();
auto texture_type_id = GenerateTypeIfNeeded(texture_type);
push_type(spv::Op::OpTypeSampledImage,
{sampled_image_type, Operand::Int(texture_type_id)});
texture_type_name_to_sampled_image_type_id_[texture_type->type_name()] =
sampled_image_type_id;
}
auto sampled_image = result_op();
if (!push_function_inst(spv::Op::OpSampledImage,
{Operand::Int(sampled_image_type_id), sampled_image,
texture_operand, sampler_operand})) {
return 0;
}
return sampled_image.to_i();
}
uint32_t Builder::GenerateBitcastExpression(
const ast::BitcastExpression* expr) {
auto result = result_op();
auto result_id = result.to_i();
auto result_type_id = GenerateTypeIfNeeded(TypeOf(expr));
if (result_type_id == 0) {
return 0;
}
auto val_id = GenerateExpressionWithLoadIfNeeded(expr->expr);
if (val_id == 0) {
return 0;
}
// Bitcast does not allow same types, just emit a CopyObject
auto* to_type = TypeOf(expr)->UnwrapRef();
auto* from_type = TypeOf(expr->expr)->UnwrapRef();
if (to_type->type_name() == from_type->type_name()) {
if (!push_function_inst(
spv::Op::OpCopyObject,
{Operand::Int(result_type_id), result, Operand::Int(val_id)})) {
return 0;
}
return result_id;
}
if (!push_function_inst(spv::Op::OpBitcast, {Operand::Int(result_type_id),
result, Operand::Int(val_id)})) {
return 0;
}
return result_id;
}
bool Builder::GenerateConditionalBlock(
const ast::Expression* cond,
const ast::BlockStatement* true_body,
size_t cur_else_idx,
const ast::ElseStatementList& else_stmts) {
auto cond_id = GenerateExpressionWithLoadIfNeeded(cond);
if (cond_id == 0) {
return false;
}
auto merge_block = result_op();
auto merge_block_id = merge_block.to_i();
if (!push_function_inst(spv::Op::OpSelectionMerge,
{Operand::Int(merge_block_id),
Operand::Int(SpvSelectionControlMaskNone)})) {
return false;
}
auto true_block = result_op();
auto true_block_id = true_block.to_i();
// if there are no more else statements we branch on false to the merge
// block otherwise we branch to the false block
auto false_block_id =
cur_else_idx < else_stmts.size() ? next_id() : merge_block_id;
if (!push_function_inst(spv::Op::OpBranchConditional,
{Operand::Int(cond_id), Operand::Int(true_block_id),
Operand::Int(false_block_id)})) {
return false;
}
// Output true block
if (!GenerateLabel(true_block_id)) {
return false;
}
if (!GenerateBlockStatement(true_body)) {
return false;
}
// We only branch if the last element of the body didn't already branch.
if (InsideBasicBlock()) {
if (!push_function_inst(spv::Op::OpBranch,
{Operand::Int(merge_block_id)})) {
return false;
}
}
// Start the false block if needed
if (false_block_id != merge_block_id) {
if (!GenerateLabel(false_block_id)) {
return false;
}
auto* else_stmt = else_stmts[cur_else_idx];
// Handle the else case by just outputting the statements.
if (!else_stmt->condition) {
if (!GenerateBlockStatement(else_stmt->body)) {
return false;
}
} else {
if (!GenerateConditionalBlock(else_stmt->condition, else_stmt->body,
cur_else_idx + 1, else_stmts)) {
return false;
}
}
if (InsideBasicBlock()) {
if (!push_function_inst(spv::Op::OpBranch,
{Operand::Int(merge_block_id)})) {
return false;
}
}
}
// Output the merge block
return GenerateLabel(merge_block_id);
}
bool Builder::GenerateIfStatement(const ast::IfStatement* stmt) {
if (!continuing_stack_.empty() &&
stmt == continuing_stack_.back().last_statement->As<ast::IfStatement>()) {
const ContinuingInfo& ci = continuing_stack_.back();
// Match one of two patterns: the break-if and break-unless patterns.
//
// The break-if pattern:
// continuing { ...
// if (cond) { break; }
// }
//
// The break-unless pattern:
// continuing { ...
// if (cond) {} else {break;}
// }
auto is_just_a_break = [](const ast::BlockStatement* block) {
return block && (block->statements.size() == 1) &&
block->Last()->Is<ast::BreakStatement>();
};
if (is_just_a_break(stmt->body) && stmt->else_statements.empty()) {
// It's a break-if.
TINT_ASSERT(Writer, !backedge_stack_.empty());
const auto cond_id = GenerateExpressionWithLoadIfNeeded(stmt->condition);
if (!cond_id) {
return false;
}
backedge_stack_.back() =
Backedge(spv::Op::OpBranchConditional,
{Operand::Int(cond_id), Operand::Int(ci.break_target_id),
Operand::Int(ci.loop_header_id)});
return true;
} else if (stmt->body->Empty()) {
const auto& es = stmt->else_statements;
if (es.size() == 1 && !es.back()->condition &&
is_just_a_break(es.back()->body)) {
// It's a break-unless.
TINT_ASSERT(Writer, !backedge_stack_.empty());
const auto cond_id =
GenerateExpressionWithLoadIfNeeded(stmt->condition);
if (!cond_id) {
return false;
}
backedge_stack_.back() =
Backedge(spv::Op::OpBranchConditional,
{Operand::Int(cond_id), Operand::Int(ci.loop_header_id),
Operand::Int(ci.break_target_id)});
return true;
}
}
}
if (!GenerateConditionalBlock(stmt->condition, stmt->body, 0,
stmt->else_statements)) {
return false;
}
return true;
}
bool Builder::GenerateSwitchStatement(const ast::SwitchStatement* stmt) {
auto merge_block = result_op();
auto merge_block_id = merge_block.to_i();
merge_stack_.push_back(merge_block_id);
auto cond_id = GenerateExpressionWithLoadIfNeeded(stmt->condition);
if (cond_id == 0) {
return false;
}
auto default_block = result_op();
auto default_block_id = default_block.to_i();
OperandList params = {Operand::Int(cond_id), Operand::Int(default_block_id)};
std::vector<uint32_t> case_ids;
for (const auto* item : stmt->body) {
if (item->IsDefault()) {
case_ids.push_back(default_block_id);
continue;
}
auto block = result_op();
auto block_id = block.to_i();
case_ids.push_back(block_id);
for (auto* selector : item->selectors) {
auto* int_literal = selector->As<ast::IntLiteralExpression>();
if (!int_literal) {
error_ = "expected integer literal for switch case label";
return false;
}
params.push_back(Operand::Int(int_literal->ValueAsU32()));
params.push_back(Operand::Int(block_id));
}
}
if (!push_function_inst(spv::Op::OpSelectionMerge,
{Operand::Int(merge_block_id),
Operand::Int(SpvSelectionControlMaskNone)})) {
return false;
}
if (!push_function_inst(spv::Op::OpSwitch, params)) {
return false;
}
bool generated_default = false;
auto& body = stmt->body;
// We output the case statements in order they were entered in the original
// source. Each fallthrough goes to the next case entry, so is a forward
// branch, otherwise the branch is to the merge block which comes after
// the switch statement.
for (uint32_t i = 0; i < body.size(); i++) {
auto* item = body[i];
if (item->IsDefault()) {
generated_default = true;
}
if (!GenerateLabel(case_ids[i])) {
return false;
}
if (!GenerateBlockStatement(item->body)) {
return false;
}
if (LastIsFallthrough(item->body)) {
if (i == (body.size() - 1)) {
// This case is caught by Resolver validation
TINT_UNREACHABLE(Writer, builder_.Diagnostics());
return false;
}
if (!push_function_inst(spv::Op::OpBranch,
{Operand::Int(case_ids[i + 1])})) {
return false;
}
} else if (InsideBasicBlock()) {
if (!push_function_inst(spv::Op::OpBranch,
{Operand::Int(merge_block_id)})) {
return false;
}
}
}
if (!generated_default) {
if (!GenerateLabel(default_block_id)) {
return false;
}
if (!push_function_inst(spv::Op::OpBranch,
{Operand::Int(merge_block_id)})) {
return false;
}
}
merge_stack_.pop_back();
return GenerateLabel(merge_block_id);
}
bool Builder::GenerateReturnStatement(const ast::ReturnStatement* stmt) {
if (stmt->value) {
auto val_id = GenerateExpressionWithLoadIfNeeded(stmt->value);
if (val_id == 0) {
return false;
}
if (!push_function_inst(spv::Op::OpReturnValue, {Operand::Int(val_id)})) {
return false;
}
} else {
if (!push_function_inst(spv::Op::OpReturn, {})) {
return false;
}
}
return true;
}
bool Builder::GenerateLoopStatement(const ast::LoopStatement* stmt) {
auto loop_header = result_op();
auto loop_header_id = loop_header.to_i();
if (!push_function_inst(spv::Op::OpBranch, {Operand::Int(loop_header_id)})) {
return false;
}
if (!GenerateLabel(loop_header_id)) {
return false;
}
auto merge_block = result_op();
auto merge_block_id = merge_block.to_i();
auto continue_block = result_op();
auto continue_block_id = continue_block.to_i();
auto body_block = result_op();
auto body_block_id = body_block.to_i();
if (!push_function_inst(
spv::Op::OpLoopMerge,
{Operand::Int(merge_block_id), Operand::Int(continue_block_id),
Operand::Int(SpvLoopControlMaskNone)})) {
return false;
}
continue_stack_.push_back(continue_block_id);
merge_stack_.push_back(merge_block_id);
// Usually, the backedge is a simple branch. This will be modified if the
// backedge block in the continuing construct has an exiting edge.
backedge_stack_.emplace_back(spv::Op::OpBranch,
OperandList{Operand::Int(loop_header_id)});
if (!push_function_inst(spv::Op::OpBranch, {Operand::Int(body_block_id)})) {
return false;
}
if (!GenerateLabel(body_block_id)) {
return false;
}
// We need variables from the body to be visible in the continuing block, so
// manage scope outside of GenerateBlockStatement.
{
scope_stack_.Push();
TINT_DEFER(scope_stack_.Pop());
if (!GenerateBlockStatementWithoutScoping(stmt->body)) {
return false;
}
// We only branch if the last element of the body didn't already branch.
if (InsideBasicBlock()) {
if (!push_function_inst(spv::Op::OpBranch,
{Operand::Int(continue_block_id)})) {
return false;
}
}
if (!GenerateLabel(continue_block_id)) {
return false;
}
if (stmt->continuing && !stmt->continuing->Empty()) {
continuing_stack_.emplace_back(stmt->continuing->Last(), loop_header_id,
merge_block_id);
if (!GenerateBlockStatementWithoutScoping(stmt->continuing)) {
return false;
}
continuing_stack_.pop_back();
}
}
// Generate the backedge.
TINT_ASSERT(Writer, !backedge_stack_.empty());
const Backedge& backedge = backedge_stack_.back();
if (!push_function_inst(backedge.opcode, backedge.operands)) {
return false;
}
backedge_stack_.pop_back();
merge_stack_.pop_back();
continue_stack_.pop_back();
return GenerateLabel(merge_block_id);
}
bool Builder::GenerateStatement(const ast::Statement* stmt) {
return Switch(
stmt,
[&](const ast::AssignmentStatement* a) {
return GenerateAssignStatement(a);
},
[&](const ast::BlockStatement* b) { //
return GenerateBlockStatement(b);
},
[&](const ast::BreakStatement* b) { //
return GenerateBreakStatement(b);
},
[&](const ast::CallStatement* c) {
return GenerateCallExpression(c->expr) != 0;
},
[&](const ast::ContinueStatement* c) {
return GenerateContinueStatement(c);
},
[&](const ast::DiscardStatement* d) {
return GenerateDiscardStatement(d);
},
[&](const ast::FallthroughStatement*) {
// Do nothing here, the fallthrough gets handled by the switch code.
return true;
},
[&](const ast::IfStatement* i) { //
return GenerateIfStatement(i);
},
[&](const ast::LoopStatement* l) { //
return GenerateLoopStatement(l);
},
[&](const ast::ReturnStatement* r) { //
return GenerateReturnStatement(r);
},
[&](const ast::SwitchStatement* s) { //
return GenerateSwitchStatement(s);
},
[&](const ast::VariableDeclStatement* v) {
return GenerateVariableDeclStatement(v);
},
[&](Default) {
error_ = "Unknown statement: " + std::string(stmt->TypeInfo().name);
return false;
});
}
bool Builder::GenerateVariableDeclStatement(
const ast::VariableDeclStatement* stmt) {
return GenerateFunctionVariable(stmt->variable);
}
uint32_t Builder::GenerateTypeIfNeeded(const sem::Type* type) {
if (type == nullptr) {
error_ = "attempting to generate type from null type";
return 0;
}
// Atomics are a type in WGSL, but aren't a distinct type in SPIR-V.
// Just emit the type inside the atomic.
if (auto* atomic = type->As<sem::Atomic>()) {
return GenerateTypeIfNeeded(atomic->Type());
}
// Pointers and references with differing accesses should not result in a
// different SPIR-V types, so we explicitly ignore the access.
// Pointers and References both map to a SPIR-V pointer type.
// Transform a Reference to a Pointer to prevent these having duplicated
// definitions in the generated SPIR-V. Note that nested pointers and
// references are not legal in WGSL, so only considering the top-level type is
// fine.
std::string type_name;
if (auto* ptr = type->As<sem::Pointer>()) {
type_name =
sem::Pointer(ptr->StoreType(), ptr->StorageClass(), ast::kReadWrite)
.type_name();
} else if (auto* ref = type->As<sem::Reference>()) {
type_name =
sem::Pointer(ref->StoreType(), ref->StorageClass(), ast::kReadWrite)
.type_name();
} else {
type_name = type->type_name();
}
return utils::GetOrCreate(type_name_to_id_, type_name, [&]() -> uint32_t {
auto result = result_op();
auto id = result.to_i();
bool ok = Switch(
type,
[&](const sem::Array* arr) { //
return GenerateArrayType(arr, result);
},
[&](const sem::Bool*) {
push_type(spv::Op::OpTypeBool, {result});
return true;
},
[&](const sem::F32*) {
push_type(spv::Op::OpTypeFloat, {result, Operand::Int(32)});
return true;
},
[&](const sem::I32*) {
push_type(spv::Op::OpTypeInt,
{result, Operand::Int(32), Operand::Int(1)});
return true;
},
[&](const sem::Matrix* mat) { //
return GenerateMatrixType(mat, result);
},
[&](const sem::Pointer* ptr) { //
return GeneratePointerType(ptr, result);
},
[&](const sem::Reference* ref) { //
return GenerateReferenceType(ref, result);
},
[&](const sem::Struct* str) { //
return GenerateStructType(str, result);
},
[&](const sem::U32*) {
push_type(spv::Op::OpTypeInt,
{result, Operand::Int(32), Operand::Int(0)});
return true;
},
[&](const sem::Vector* vec) { //
return GenerateVectorType(vec, result);
},
[&](const sem::Void*) {
push_type(spv::Op::OpTypeVoid, {result});
return true;
},
[&](const sem::StorageTexture* tex) {
if (!GenerateTextureType(tex, result)) {
return false;
}
// Register all three access types of StorageTexture names. In
// SPIR-V, we must output a single type, while the variable is
// annotated with the access type. Doing this ensures we de-dupe.
type_name_to_id_[builder_
.create<sem::StorageTexture>(
tex->dim(), tex->texel_format(),
ast::Access::kRead, tex->type())
->type_name()] = id;
type_name_to_id_[builder_
.create<sem::StorageTexture>(
tex->dim(), tex->texel_format(),
ast::Access::kWrite, tex->type())
->type_name()] = id;
type_name_to_id_[builder_
.create<sem::StorageTexture>(
tex->dim(), tex->texel_format(),
ast::Access::kReadWrite, tex->type())
->type_name()] = id;
return true;
},
[&](const sem::Texture* tex) {
return GenerateTextureType(tex, result);
},
[&](const sem::Sampler*) {
push_type(spv::Op::OpTypeSampler, {result});
// Register both of the sampler type names. In SPIR-V they're the same
// sampler type, so we need to match that when we do the dedup check.
type_name_to_id_["__sampler_sampler"] = id;
type_name_to_id_["__sampler_comparison"] = id;
return true;
},
[&](Default) {
error_ = "unable to convert type: " + type->type_name();
return false;
});
if (!ok) {
return 0;
}
return id;
});
}
bool Builder::GenerateTextureType(const sem::Texture* texture,
const Operand& result) {
uint32_t array_literal = 0u;
const auto dim = texture->dim();
if (dim == ast::TextureDimension::k2dArray ||
dim == ast::TextureDimension::kCubeArray) {
array_literal = 1u;
}
uint32_t dim_literal = SpvDim2D;
if (dim == ast::TextureDimension::k1d) {
dim_literal = SpvDim1D;
if (texture->Is<sem::SampledTexture>()) {
push_capability(SpvCapabilitySampled1D);
} else if (texture->Is<sem::StorageTexture>()) {
push_capability(SpvCapabilityImage1D);
}
}
if (dim == ast::TextureDimension::k3d) {
dim_literal = SpvDim3D;
}
if (dim == ast::TextureDimension::kCube ||
dim == ast::TextureDimension::kCubeArray) {
dim_literal = SpvDimCube;
}
uint32_t ms_literal = 0u;
if (texture->IsAnyOf<sem::MultisampledTexture,
sem::DepthMultisampledTexture>()) {
ms_literal = 1u;
}
uint32_t depth_literal = 0u;
if (texture->IsAnyOf<sem::DepthTexture, sem::DepthMultisampledTexture>()) {
depth_literal = 1u;
}
uint32_t sampled_literal = 2u;
if (texture->IsAnyOf<sem::MultisampledTexture, sem::SampledTexture,
sem::DepthTexture, sem::DepthMultisampledTexture>()) {
sampled_literal = 1u;
}
if (dim == ast::TextureDimension::kCubeArray) {
if (texture->IsAnyOf<sem::SampledTexture, sem::DepthTexture>()) {
push_capability(SpvCapabilitySampledCubeArray);
}
}
uint32_t type_id = Switch(
texture,
[&](const sem::DepthTexture*) {
return GenerateTypeIfNeeded(builder_.create<sem::F32>());
},
[&](const sem::DepthMultisampledTexture*) {
return GenerateTypeIfNeeded(builder_.create<sem::F32>());
},
[&](const sem::SampledTexture* t) {
return GenerateTypeIfNeeded(t->type());
},
[&](const sem::MultisampledTexture* t) {
return GenerateTypeIfNeeded(t->type());
},
[&](const sem::StorageTexture* t) {
return GenerateTypeIfNeeded(t->type());
},
[&](Default) -> uint32_t { //
return 0u;
});
if (type_id == 0u) {
return false;
}
uint32_t format_literal = SpvImageFormat_::SpvImageFormatUnknown;
if (auto* t = texture->As<sem::StorageTexture>()) {
format_literal = convert_texel_format_to_spv(t->texel_format());
}
push_type(spv::Op::OpTypeImage,
{result, Operand::Int(type_id), Operand::Int(dim_literal),
Operand::Int(depth_literal), Operand::Int(array_literal),
Operand::Int(ms_literal), Operand::Int(sampled_literal),
Operand::Int(format_literal)});
return true;
}
bool Builder::GenerateArrayType(const sem::Array* ary, const Operand& result) {
auto elem_type = GenerateTypeIfNeeded(ary->ElemType());
if (elem_type == 0) {
return false;
}
auto result_id = result.to_i();
if (ary->IsRuntimeSized()) {
push_type(spv::Op::OpTypeRuntimeArray, {result, Operand::Int(elem_type)});
} else {
auto len_id = GenerateConstantIfNeeded(ScalarConstant::U32(ary->Count()));
if (len_id == 0) {
return false;
}
push_type(spv::Op::OpTypeArray,
{result, Operand::Int(elem_type), Operand::Int(len_id)});
}
push_annot(spv::Op::OpDecorate,
{Operand::Int(result_id), Operand::Int(SpvDecorationArrayStride),
Operand::Int(ary->Stride())});
return true;
}
bool Builder::GenerateMatrixType(const sem::Matrix* mat,
const Operand& result) {
auto* col_type = builder_.create<sem::Vector>(mat->type(), mat->rows());
auto col_type_id = GenerateTypeIfNeeded(col_type);
if (has_error()) {
return false;
}
push_type(spv::Op::OpTypeMatrix,
{result, Operand::Int(col_type_id), Operand::Int(mat->columns())});
return true;
}
bool Builder::GeneratePointerType(const sem::Pointer* ptr,
const Operand& result) {
auto subtype_id = GenerateTypeIfNeeded(ptr->StoreType());
if (subtype_id == 0) {
return false;
}
auto stg_class = ConvertStorageClass(ptr->StorageClass());
if (stg_class == SpvStorageClassMax) {
error_ = "invalid storage class for pointer";
return false;
}
push_type(spv::Op::OpTypePointer,
{result, Operand::Int(stg_class), Operand::Int(subtype_id)});
return true;
}
bool Builder::GenerateReferenceType(const sem::Reference* ref,
const Operand& result) {
auto subtype_id = GenerateTypeIfNeeded(ref->StoreType());
if (subtype_id == 0) {
return false;
}
auto stg_class = ConvertStorageClass(ref->StorageClass());
if (stg_class == SpvStorageClassMax) {
error_ = "invalid storage class for reference";
return false;
}
push_type(spv::Op::OpTypePointer,
{result, Operand::Int(stg_class), Operand::Int(subtype_id)});
return true;
}
bool Builder::GenerateStructType(const sem::Struct* struct_type,
const Operand& result) {
auto struct_id = result.to_i();
if (struct_type->Name().IsValid()) {
push_debug(
spv::Op::OpName,
{Operand::Int(struct_id),
Operand::String(builder_.Symbols().NameFor(struct_type->Name()))});
}
OperandList ops;
ops.push_back(result);
auto* decl = struct_type->Declaration();
if (decl &&
ast::HasAttribute<transform::AddSpirvBlockAttribute::SpirvBlockAttribute>(
decl->attributes)) {
push_annot(spv::Op::OpDecorate,
{Operand::Int(struct_id), Operand::Int(SpvDecorationBlock)});
}
for (uint32_t i = 0; i < struct_type->Members().size(); ++i) {
auto mem_id = GenerateStructMember(struct_id, i, struct_type->Members()[i]);
if (mem_id == 0) {
return false;
}
ops.push_back(Operand::Int(mem_id));
}
push_type(spv::Op::OpTypeStruct, std::move(ops));
return true;
}
uint32_t Builder::GenerateStructMember(uint32_t struct_id,
uint32_t idx,
const sem::StructMember* member) {
push_debug(spv::Op::OpMemberName,
{Operand::Int(struct_id), Operand::Int(idx),
Operand::String(builder_.Symbols().NameFor(member->Name()))});
// Note: This will generate layout annotations for *all* structs, whether or
// not they are used in host-shareable variables. This is officially ok in
// SPIR-V 1.0 through 1.3. If / when we migrate to using SPIR-V 1.4 we'll have
// to only generate the layout info for structs used for certain storage
// classes.
push_annot(
spv::Op::OpMemberDecorate,
{Operand::Int(struct_id), Operand::Int(idx),
Operand::Int(SpvDecorationOffset), Operand::Int(member->Offset())});
// Infer and emit matrix layout.
auto* matrix_type = GetNestedMatrixType(member->Type());
if (matrix_type) {
push_annot(spv::Op::OpMemberDecorate,
{Operand::Int(struct_id), Operand::Int(idx),
Operand::Int(SpvDecorationColMajor)});
if (!matrix_type->type()->Is<sem::F32>()) {
error_ = "matrix scalar element type must be f32";
return 0;
}
const auto scalar_elem_size = 4;
const auto effective_row_count = (matrix_type->rows() == 2) ? 2 : 4;
push_annot(spv::Op::OpMemberDecorate,
{Operand::Int(struct_id), Operand::Int(idx),
Operand::Int(SpvDecorationMatrixStride),
Operand::Int(effective_row_count * scalar_elem_size)});
}
return GenerateTypeIfNeeded(member->Type());
}
bool Builder::GenerateVectorType(const sem::Vector* vec,
const Operand& result) {
auto type_id = GenerateTypeIfNeeded(vec->type());
if (has_error()) {
return false;
}
push_type(spv::Op::OpTypeVector,
{result, Operand::Int(type_id), Operand::Int(vec->Width())});
return true;
}
SpvStorageClass Builder::ConvertStorageClass(ast::StorageClass klass) const {
switch (klass) {
case ast::StorageClass::kInvalid:
return SpvStorageClassMax;
case ast::StorageClass::kInput:
return SpvStorageClassInput;
case ast::StorageClass::kOutput:
return SpvStorageClassOutput;
case ast::StorageClass::kUniform:
return SpvStorageClassUniform;
case ast::StorageClass::kWorkgroup:
return SpvStorageClassWorkgroup;
case ast::StorageClass::kUniformConstant:
return SpvStorageClassUniformConstant;
case ast::StorageClass::kStorage:
return SpvStorageClassStorageBuffer;
case ast::StorageClass::kPrivate:
return SpvStorageClassPrivate;
case ast::StorageClass::kFunction:
return SpvStorageClassFunction;
case ast::StorageClass::kNone:
break;
}
return SpvStorageClassMax;
}
SpvBuiltIn Builder::ConvertBuiltin(ast::Builtin builtin,
ast::StorageClass storage) {
switch (builtin) {
case ast::Builtin::kPosition:
if (storage == ast::StorageClass::kInput) {
return SpvBuiltInFragCoord;
} else if (storage == ast::StorageClass::kOutput) {
return SpvBuiltInPosition;
} else {
TINT_ICE(Writer, builder_.Diagnostics())
<< "invalid storage class for builtin";
break;
}
case ast::Builtin::kVertexIndex:
return SpvBuiltInVertexIndex;
case ast::Builtin::kInstanceIndex:
return SpvBuiltInInstanceIndex;
case ast::Builtin::kFrontFacing:
return SpvBuiltInFrontFacing;
case ast::Builtin::kFragDepth:
return SpvBuiltInFragDepth;
case ast::Builtin::kLocalInvocationId:
return SpvBuiltInLocalInvocationId;
case ast::Builtin::kLocalInvocationIndex:
return SpvBuiltInLocalInvocationIndex;
case ast::Builtin::kGlobalInvocationId:
return SpvBuiltInGlobalInvocationId;
case ast::Builtin::kPointSize:
return SpvBuiltInPointSize;
case ast::Builtin::kWorkgroupId:
return SpvBuiltInWorkgroupId;
case ast::Builtin::kNumWorkgroups:
return SpvBuiltInNumWorkgroups;
case ast::Builtin::kSampleIndex:
push_capability(SpvCapabilitySampleRateShading);
return SpvBuiltInSampleId;
case ast::Builtin::kSampleMask:
return SpvBuiltInSampleMask;
case ast::Builtin::kNone:
break;
}
return SpvBuiltInMax;
}
void Builder::AddInterpolationDecorations(uint32_t id,
ast::InterpolationType type,
ast::InterpolationSampling sampling) {
switch (type) {
case ast::InterpolationType::kLinear:
push_annot(spv::Op::OpDecorate,
{Operand::Int(id), Operand::Int(SpvDecorationNoPerspective)});
break;
case ast::InterpolationType::kFlat:
push_annot(spv::Op::OpDecorate,
{Operand::Int(id), Operand::Int(SpvDecorationFlat)});
break;
case ast::InterpolationType::kPerspective:
break;
}
switch (sampling) {
case ast::InterpolationSampling::kCentroid:
push_annot(spv::Op::OpDecorate,
{Operand::Int(id), Operand::Int(SpvDecorationCentroid)});
break;
case ast::InterpolationSampling::kSample:
push_capability(SpvCapabilitySampleRateShading);
push_annot(spv::Op::OpDecorate,
{Operand::Int(id), Operand::Int(SpvDecorationSample)});
break;
case ast::InterpolationSampling::kCenter:
case ast::InterpolationSampling::kNone:
break;
}
}
SpvImageFormat Builder::convert_texel_format_to_spv(
const ast::TexelFormat format) {
switch (format) {
case ast::TexelFormat::kR32Uint:
return SpvImageFormatR32ui;
case ast::TexelFormat::kR32Sint:
return SpvImageFormatR32i;
case ast::TexelFormat::kR32Float:
return SpvImageFormatR32f;
case ast::TexelFormat::kRgba8Unorm:
return SpvImageFormatRgba8;
case ast::TexelFormat::kRgba8Snorm:
return SpvImageFormatRgba8Snorm;
case ast::TexelFormat::kRgba8Uint:
return SpvImageFormatRgba8ui;
case ast::TexelFormat::kRgba8Sint:
return SpvImageFormatRgba8i;
case ast::TexelFormat::kRg32Uint:
push_capability(SpvCapabilityStorageImageExtendedFormats);
return SpvImageFormatRg32ui;
case ast::TexelFormat::kRg32Sint:
push_capability(SpvCapabilityStorageImageExtendedFormats);
return SpvImageFormatRg32i;
case ast::TexelFormat::kRg32Float:
push_capability(SpvCapabilityStorageImageExtendedFormats);
return SpvImageFormatRg32f;
case ast::TexelFormat::kRgba16Uint:
return SpvImageFormatRgba16ui;
case ast::TexelFormat::kRgba16Sint:
return SpvImageFormatRgba16i;
case ast::TexelFormat::kRgba16Float:
return SpvImageFormatRgba16f;
case ast::TexelFormat::kRgba32Uint:
return SpvImageFormatRgba32ui;
case ast::TexelFormat::kRgba32Sint:
return SpvImageFormatRgba32i;
case ast::TexelFormat::kRgba32Float:
return SpvImageFormatRgba32f;
case ast::TexelFormat::kNone:
return SpvImageFormatUnknown;
}
return SpvImageFormatUnknown;
}
bool Builder::push_function_inst(spv::Op op, const OperandList& operands) {
if (functions_.empty()) {
std::ostringstream ss;
ss << "Internal error: trying to add SPIR-V instruction " << int(op)
<< " outside a function";
error_ = ss.str();
return false;
}
functions_.back().push_inst(op, operands);
return true;
}
bool Builder::InsideBasicBlock() const {
if (functions_.empty()) {
return false;
}
const auto& instructions = functions_.back().instructions();
if (instructions.empty()) {
// The Function object does not explicitly represent its entry block
// label. So return *true* because an empty list means the only
// thing in the function is that entry block label.
return true;
}
const auto& inst = instructions.back();
switch (inst.opcode()) {
case spv::Op::OpBranch:
case spv::Op::OpBranchConditional:
case spv::Op::OpSwitch:
case spv::Op::OpReturn:
case spv::Op::OpReturnValue:
case spv::Op::OpUnreachable:
case spv::Op::OpKill:
case spv::Op::OpTerminateInvocation:
return false;
default:
break;
}
return true;
}
Builder::ContinuingInfo::ContinuingInfo(
const ast::Statement* the_last_statement,
uint32_t loop_id,
uint32_t break_id)
: last_statement(the_last_statement),
loop_header_id(loop_id),
break_target_id(break_id) {
TINT_ASSERT(Writer, last_statement != nullptr);
TINT_ASSERT(Writer, loop_header_id != 0u);
TINT_ASSERT(Writer, break_target_id != 0u);
}
Builder::Backedge::Backedge(spv::Op the_opcode, OperandList the_operands)
: opcode(the_opcode), operands(the_operands) {}
Builder::Backedge::Backedge(const Builder::Backedge& other) = default;
Builder::Backedge& Builder::Backedge::operator=(
const Builder::Backedge& other) = default;
Builder::Backedge::~Backedge() = default;
} // namespace spirv
} // namespace writer
} // namespace tint