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// Copyright 2023 The Dawn & Tint Authors
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this
// list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "src/tint/lang/glsl/writer/printer/printer.h"
#include <string>
#include <utility>
#include "src/tint/lang/core/builtin_fn.h"
#include "src/tint/lang/core/constant/splat.h"
#include "src/tint/lang/core/ir/access.h"
#include "src/tint/lang/core/ir/bitcast.h"
#include "src/tint/lang/core/ir/break_if.h"
#include "src/tint/lang/core/ir/construct.h"
#include "src/tint/lang/core/ir/continue.h"
#include "src/tint/lang/core/ir/convert.h"
#include "src/tint/lang/core/ir/core_binary.h"
#include "src/tint/lang/core/ir/core_builtin_call.h"
#include "src/tint/lang/core/ir/core_unary.h"
#include "src/tint/lang/core/ir/discard.h"
#include "src/tint/lang/core/ir/exit_if.h"
#include "src/tint/lang/core/ir/exit_loop.h"
#include "src/tint/lang/core/ir/exit_switch.h"
#include "src/tint/lang/core/ir/function.h"
#include "src/tint/lang/core/ir/if.h"
#include "src/tint/lang/core/ir/let.h"
#include "src/tint/lang/core/ir/load.h"
#include "src/tint/lang/core/ir/load_vector_element.h"
#include "src/tint/lang/core/ir/loop.h"
#include "src/tint/lang/core/ir/module.h"
#include "src/tint/lang/core/ir/multi_in_block.h"
#include "src/tint/lang/core/ir/next_iteration.h"
#include "src/tint/lang/core/ir/return.h"
#include "src/tint/lang/core/ir/store.h"
#include "src/tint/lang/core/ir/store_vector_element.h"
#include "src/tint/lang/core/ir/switch.h"
#include "src/tint/lang/core/ir/swizzle.h"
#include "src/tint/lang/core/ir/terminate_invocation.h"
#include "src/tint/lang/core/ir/unreachable.h"
#include "src/tint/lang/core/ir/user_call.h"
#include "src/tint/lang/core/ir/validator.h"
#include "src/tint/lang/core/ir/var.h"
#include "src/tint/lang/core/texel_format.h"
#include "src/tint/lang/core/type/array.h"
#include "src/tint/lang/core/type/bool.h"
#include "src/tint/lang/core/type/depth_multisampled_texture.h"
#include "src/tint/lang/core/type/depth_texture.h"
#include "src/tint/lang/core/type/f16.h"
#include "src/tint/lang/core/type/f32.h"
#include "src/tint/lang/core/type/i32.h"
#include "src/tint/lang/core/type/matrix.h"
#include "src/tint/lang/core/type/multisampled_texture.h"
#include "src/tint/lang/core/type/pointer.h"
#include "src/tint/lang/core/type/sampled_texture.h"
#include "src/tint/lang/core/type/storage_texture.h"
#include "src/tint/lang/core/type/u32.h"
#include "src/tint/lang/core/type/vector.h"
#include "src/tint/lang/core/type/void.h"
#include "src/tint/lang/glsl/ir/builtin_call.h"
#include "src/tint/lang/glsl/ir/member_builtin_call.h"
#include "src/tint/lang/glsl/ir/ternary.h"
#include "src/tint/lang/glsl/writer/common/printer_support.h"
#include "src/tint/lang/glsl/writer/common/version.h"
#include "src/tint/utils/containers/map.h"
#include "src/tint/utils/generator/text_generator.h"
#include "src/tint/utils/macros/scoped_assignment.h"
#include "src/tint/utils/rtti/switch.h"
#include "src/tint/utils/text/string.h"
using namespace tint::core::fluent_types; // NOLINT
namespace tint::glsl::writer {
namespace {
constexpr const char* kAMDGpuShaderHalfFloat = "GL_AMD_gpu_shader_half_float";
constexpr const char* kOESSampleVariables = "GL_OES_sample_variables";
constexpr const char* kEXTBlendFuncExtended = "GL_EXT_blend_func_extended";
constexpr const char* kEXTTextureShadowLod = "GL_EXT_texture_shadow_lod";
enum class LayoutFormat : uint8_t {
kStd140,
kStd430,
};
/// PIMPL class for the MSL generator
class Printer : public tint::TextGenerator {
public:
/// Constructor
/// @param module the Tint IR module to generate
/// @param version the GLSL version information
Printer(core::ir::Module& module, const Version& version) : ir_(module), version_(version) {}
/// @returns the generated GLSL shader
tint::Result<std::string> Generate() {
auto valid = core::ir::ValidateAndDumpIfNeeded(
ir_, "GLSL writer",
core::ir::Capabilities{core::ir::Capability::kAllowHandleVarsWithoutBindings});
if (valid != Success) {
return std::move(valid.Failure());
}
{
TINT_SCOPED_ASSIGNMENT(current_buffer_, &header_buffer_);
auto out = Line();
out << "#version " << version_.major_version << version_.minor_version << "0";
if (version_.IsES()) {
out << " es";
}
}
EmitRootBlock();
// Emit functions.
for (auto& func : ir_.DependencyOrderedFunctions()) {
EmitFunction(func);
}
StringStream ss;
auto header = header_buffer_.String();
if (!header.empty()) {
ss << header << "\n";
}
auto preamble = preamble_buffer_.String();
if (!preamble.empty()) {
ss << preamble << "\n";
}
ss << main_buffer_.String();
return ss.str();
}
private:
core::ir::Module& ir_;
const Version& version_;
/// The buffer holding header text
TextBuffer header_buffer_;
/// The buffer holding preamble text
TextBuffer preamble_buffer_;
/// The current function being emitted
const core::ir::Function* current_function_ = nullptr;
/// The current block being emitted
const core::ir::Block* current_block_ = nullptr;
Hashset<std::string, 4> emitted_extensions_;
/// A hashmap of value to name
Hashmap<const core::ir::Value*, std::string, 32> names_;
/// Map of builtin structure to unique generated name
Hashmap<const core::type::Struct*, std::string, 4> builtin_struct_names_;
// The set of emitted structs
Hashset<const core::type::Struct*, 4> emitted_structs_;
/// Block to emit for a continuing
std::function<void()> emit_continuing_;
/// @returns the name of the given value, creating a new unique name if the value is unnamed in
/// the module.
std::string NameOf(const core::ir::Value* value) {
return names_.GetOrAdd(value, [&] {
auto sym = ir_.NameOf(value);
return sym.IsValid() ? sym.Name() : UniqueIdentifier("v");
});
}
/// @return a new, unique identifier with the given prefix.
/// @param prefix optional prefix to apply to the generated identifier. If empty
/// "tint_symbol" will be used.
std::string UniqueIdentifier(const std::string& prefix /* = "" */) {
return ir_.symbols.New(prefix).Name();
}
/// @param s the structure
/// @returns the name of the structure, taking special care of builtin structures that start
/// with double underscores. If the structure is a builtin, then the returned name will be a
/// unique name without the leading underscores.
std::string StructName(const core::type::Struct* s) {
auto name = s->Name().Name();
if (HasPrefix(name, "__")) {
name =
builtin_struct_names_.GetOrAdd(s, [&] { return UniqueIdentifier(name.substr(2)); });
}
return name;
}
void EmitRootBlock() {
TINT_SCOPED_ASSIGNMENT(current_block_, ir_.root_block);
for (auto* inst : *ir_.root_block) {
tint::Switch(
inst, //
[&](core::ir::Var* v) { EmitGlobalVar(v); },
TINT_ICE_ON_NO_MATCH);
}
}
/// Emit the function
/// @param func the function to emit
void EmitFunction(const core::ir::Function* func) {
TINT_SCOPED_ASSIGNMENT(current_function_, func);
{
auto out = Line();
if (func->Stage() == core::ir::Function::PipelineStage::kCompute) {
auto wg_opt = func->WorkgroupSize();
TINT_ASSERT(wg_opt.has_value());
auto& wg = wg_opt.value();
Line() << "layout(local_size_x = " << wg[0] << ", local_size_y = " << wg[1]
<< ", local_size_z = " << wg[2] << ") in;";
}
EmitType(out, func->ReturnType());
out << " ";
// Fragment shaders need a precision statement
if (func->Stage() == core::ir::Function::PipelineStage::kFragment) {
auto pre = Line(&header_buffer_);
pre << "precision highp float;\n";
pre << "precision highp int;";
}
// Switch the entry point name to `main`. This makes the assumption that single entry
// point is always run for GLSL, which is has to be, there can be only one entry point.
// So, we swap the entry point name to `main` which is required for GLSL.
if (func->Stage() != core::ir::Function::PipelineStage::kUndefined) {
out << "main";
} else {
out << ir_.NameOf(func).Name();
}
out << "(";
size_t i = 0;
for (auto* param : func->Params()) {
if (i > 0) {
out << ", ";
}
++i;
const core::type::Type* type = param->Type();
if (auto* ptr = type->As<core::type::Pointer>()) {
// Transform pointer parameters in to `inout` parameters.
out << "inout ";
type = ptr->StoreType();
}
EmitTypeAndName(out, type, NameOf(param));
}
out << ") {";
}
{
ScopedIndent si(current_buffer_);
EmitBlock(func->Block());
}
Line() << "}";
}
/// Emit a block
/// @param block the block to emit
void EmitBlock(const core::ir::Block* block) {
TINT_SCOPED_ASSIGNMENT(current_block_, block);
for (auto* inst : *block) {
tint::Switch(
inst, //
// TerminateInvocation must come before Call.
[&](const core::ir::TerminateInvocation*) { EmitDiscard(); }, //
[&](const core::ir::BreakIf* i) { EmitBreakIf(i); }, //
[&](const core::ir::Call* i) { EmitCallStmt(i); }, //
[&](const core::ir::Continue*) { EmitContinue(); }, //
[&](const core::ir::ExitIf*) { /* do nothing handled by transform */ }, //
[&](const core::ir::ExitLoop*) { EmitExitLoop(); }, //
[&](const core::ir::ExitSwitch*) { EmitExitSwitch(); }, //
[&](const core::ir::If* i) { EmitIf(i); }, //
[&](const core::ir::Let* i) { EmitLet(i); }, //
[&](const core::ir::Loop* l) { EmitLoop(l); }, //
[&](const core::ir::Return* r) { EmitReturn(r); }, //
[&](const core::ir::Store* s) { EmitStore(s); }, //
[&](const core::ir::StoreVectorElement* s) { EmitStoreVectorElement(s); }, //
[&](const core::ir::Switch* i) { EmitSwitch(i); }, //
[&](const core::ir::Unreachable*) { EmitUnreachable(); }, //
[&](const core::ir::Var* v) { EmitVar(Line(), v); }, //
[&](const core::ir::NextIteration*) { /* do nothing */ }, //
[&](const core::ir::ExitIf*) { /* do nothing handled by transform */ }, //
//
[&](const core::ir::Access*) { /* inlined */ }, //
[&](const core::ir::Bitcast*) { /* inlined */ }, //
[&](const core::ir::Construct*) { /* inlined */ }, //
[&](const core::ir::CoreBinary*) { /* inlined */ }, //
[&](const core::ir::CoreUnary*) { /* inlined */ }, //
[&](const core::ir::Load*) { /* inlined */ }, //
[&](const core::ir::LoadVectorElement*) { /* inlined */ }, //
[&](const core::ir::Swizzle*) { /* inlined */ }, //
TINT_ICE_ON_NO_MATCH);
}
}
void EmitStoreVectorElement(const core::ir::StoreVectorElement* l) {
auto out = Line();
EmitValue(out, l->To());
out << "[";
EmitValue(out, l->Index());
out << "] = ";
EmitValue(out, l->Value());
out << ";";
}
void IdxToComponent(StringStream& out, uint32_t idx) {
switch (idx) {
case 0:
out << "x";
break;
case 1:
out << "y";
break;
case 2:
out << "z";
break;
case 3:
out << "w";
break;
default:
TINT_UNREACHABLE() << "invalid index for component";
}
}
void EmitLoadVectorElement(StringStream& out, const core::ir::LoadVectorElement* l) {
EmitValue(out, l->From());
if (auto* cnst = l->Index()->As<core::ir::Constant>()) {
out << ".";
IdxToComponent(out, cnst->Value()->ValueAs<uint32_t>());
} else {
out << "[";
EmitValue(out, l->Index());
out << "]";
}
}
void EmitSwizzle(StringStream& out, const core::ir::Swizzle* swizzle) {
EmitValue(out, swizzle->Object());
out << ".";
for (const auto i : swizzle->Indices()) {
IdxToComponent(out, i);
}
}
void EmitDiscard() { Line() << "discard;"; }
void EmitContinue() {
if (emit_continuing_) {
emit_continuing_();
}
Line() << "continue;";
}
void EmitExitLoop() { Line() << "break;"; }
void EmitLoop(const core::ir::Loop* l) {
// Note, we can't just emit the continuing inside a conditional at the top of the loop
// because any variable declared in the block must be visible to the continuing.
//
// loop {
// var a = 3;
// continue {
// let y = a;
// }
// }
auto emit_continuing = [&] {
Line() << "{";
{
const ScopedIndent si(current_buffer_);
EmitBlock(l->Continuing());
}
Line() << "}";
};
TINT_SCOPED_ASSIGNMENT(emit_continuing_, emit_continuing);
Line() << "{";
{
ScopedIndent init(current_buffer_);
EmitBlock(l->Initializer());
Line() << "while(true) {";
{
ScopedIndent si(current_buffer_);
EmitBlock(l->Body());
}
Line() << "}";
}
Line() << "}";
}
/// Emit an if instruction
/// @param if_ the if instruction
void EmitIf(const core::ir::If* if_) {
{
auto out = Line();
out << "if (";
EmitValue(out, if_->Condition());
out << ") {";
}
{
const ScopedIndent si(current_buffer_);
EmitBlock(if_->True());
}
if (if_->False() && !if_->False()->IsEmpty()) {
Line() << "} else {";
const ScopedIndent si(current_buffer_);
EmitBlock(if_->False());
}
Line() << "}";
}
void EmitBreakIf(const core::ir::BreakIf* b) {
auto out = Line();
out << "if (";
EmitValue(out, b->Condition());
out << ") { break; }";
}
void EmitExitSwitch() { Line() << "break;"; }
void EmitSwitch(const core::ir::Switch* s) {
{
auto out = Line();
out << "switch(";
EmitValue(out, s->Condition());
out << ") {";
}
{
const ScopedIndent blk(current_buffer_);
for (auto& case_ : s->Cases()) {
for (auto& sel : case_.selectors) {
if (sel.IsDefault()) {
Line() << "default:";
} else {
auto out = Line();
out << "case ";
EmitValue(out, sel.val);
out << ":";
}
}
Line() << "{";
{
const ScopedIndent ci(current_buffer_);
EmitBlock(case_.block);
}
Line() << "}";
}
}
Line() << "}";
}
/// Emit an access instruction
void EmitAccess(StringStream& out, const core::ir::Access* a) {
EmitValue(out, a->Object());
auto* current_type = a->Object()->Type()->UnwrapPtr();
for (auto* index : a->Indices()) {
TINT_ASSERT(current_type);
Switch(
current_type, //
[&](const core::type::Struct* s) {
auto* c = index->As<core::ir::Constant>();
auto* member = s->Members()[c->Value()->ValueAs<uint32_t>()];
out << "." << member->Name().Name();
current_type = member->Type();
},
[&](Default) {
out << "[";
EmitValue(out, index);
out << "]";
current_type = current_type->Element(0);
});
}
}
void EmitLet(const core::ir::Let* l) {
TINT_ASSERT(!l->Result(0)->Type()->Is<core::type::Pointer>());
auto out = Line();
// TODO(dsinclair): Investigate using `const` here as well, the AST printer doesn't emit
// const with a let, but we should be able to.
EmitTypeAndName(out, l->Result(0)->Type(), NameOf(l->Result(0)));
out << " = ";
EmitValue(out, l->Value());
out << ";";
}
void EmitCallStmt(const core::ir::Call* c) {
if (!c->Result(0)->IsUsed()) {
auto out = Line();
EmitValue(out, c->Result(0));
out << ";";
}
}
void EmitExtension(std::string name) {
if (emitted_extensions_.Contains(name)) {
return;
}
emitted_extensions_.Add(name);
TINT_SCOPED_ASSIGNMENT(current_buffer_, &header_buffer_);
Line() << "#extension " << name << ": require";
}
void EmitTypeAndName(StringStream& out, const core::type::Type* type, const std::string& name) {
bool name_printed = false;
EmitType(out, type, name, &name_printed);
if (!name.empty() && !name_printed) {
out << " " << name;
}
}
/// Emit a type
/// @param out the stream to emit too
/// @param type the type to emit
void EmitType(StringStream& out,
const core::type::Type* type,
[[maybe_unused]] const std::string& name = "",
bool* name_printed = nullptr) {
if (name_printed) {
*name_printed = false;
}
if (auto* ptr = type->As<core::type::MemoryView>()) {
switch (ptr->AddressSpace()) {
case core::AddressSpace::kIn: {
out << "in ";
break;
}
case core::AddressSpace::kOut: {
out << "out ";
break;
}
case core::AddressSpace::kUniform:
case core::AddressSpace::kPushConstant:
case core::AddressSpace::kHandle: {
out << "uniform ";
break;
}
default:
break;
}
}
tint::Switch(
type, //
[&](const core::type::Array* ary) { EmitArrayType(out, ary, name, name_printed); },
[&](const core::type::Atomic* a) { EmitType(out, a->Type(), name, name_printed); },
[&](const core::type::Bool*) { out << "bool"; },
[&](const core::type::I32*) { out << "int"; },
[&](const core::type::U32*) { out << "uint"; },
[&](const core::type::Void*) { out << "void"; },
[&](const core::type::F32*) { out << "float"; },
[&](const core::type::F16*) {
EmitExtension(kAMDGpuShaderHalfFloat);
out << "float16_t";
},
[&](const core::type::Pointer* p) {
EmitType(out, p->StoreType(), name, name_printed);
},
[&](const core::type::Vector* v) { EmitVectorType(out, v); },
[&](const core::type::Matrix* m) { EmitMatrixType(out, m); },
[&](const core::type::Struct* s) {
EmitStructType(s);
out << StructName(s);
},
[&](const core::type::Texture* t) { EmitTextureType(out, t); },
TINT_ICE_ON_NO_MATCH);
}
void EmitStructType(const core::type::Struct* str) {
if (!emitted_structs_.Add(str)) {
return;
}
// This does not append directly to the preamble because a struct may require other
// structs to get emitted before it. So, the struct emits into a temporary text buffer, then
// anything it depends on will emit to the preamble first, and then it copies the text
// buffer into the preamble.
TextBuffer str_buf;
Line(&str_buf) << "\n" << "struct " << StructName(str) << " {";
str_buf.IncrementIndent();
for (auto* mem : str->Members()) {
auto out = Line(&str_buf);
EmitTypeAndName(out, mem->Type(), mem->Name().Name());
out << ";";
}
str_buf.DecrementIndent();
Line(&str_buf) << "};";
preamble_buffer_.Append(str_buf);
}
void EmitVectorType(StringStream& out, const core::type::Vector* v) {
tint::Switch(
v->Type(), //
[&](const core::type::F32*) {}, //
[&](const core::type::F16*) {
EmitExtension(kAMDGpuShaderHalfFloat);
out << "f16";
},
[&](const core::type::I32*) { out << "i"; },
[&](const core::type::U32*) { out << "u"; },
[&](const core::type::Bool*) { out << "b"; }, //
TINT_ICE_ON_NO_MATCH);
out << "vec" << v->Width();
}
void EmitMatrixType(StringStream& out, const core::type::Matrix* m) {
if (m->Type()->Is<core::type::F16>()) {
EmitExtension(kAMDGpuShaderHalfFloat);
out << "f16";
}
out << "mat" << m->Columns();
if (m->Rows() != m->Columns()) {
out << "x" << m->Rows();
}
}
void EmitArrayType(StringStream& out,
const core::type::Array* ary,
const std::string& name,
bool* name_printed) {
std::stringstream args;
const core::type::Type* ty = ary;
while (auto* arr = ty->As<core::type::Array>()) {
if (arr->Count()->Is<core::type::RuntimeArrayCount>()) {
args << "[]";
} else {
auto count = arr->ConstantCount();
TINT_ASSERT(count.has_value());
args << "[" << count.value() << "]";
}
ty = arr->ElemType();
}
EmitType(out, ty);
if (!name.empty()) {
out << " " << name;
if (name_printed) {
*name_printed = true;
}
}
out << args.str();
}
void EmitTextureType(StringStream& out, const core::type::Texture* t) {
TINT_ASSERT(!t->Is<core::type::ExternalTexture>());
auto* storage = t->As<core::type::StorageTexture>();
auto* sampled = t->As<core::type::SampledTexture>();
auto* ms = t->As<core::type::MultisampledTexture>();
auto* depth_ms = t->As<core::type::DepthMultisampledTexture>();
out << "highp ";
if (storage) {
switch (storage->Access()) {
case core::Access::kRead:
out << "readonly ";
break;
case core::Access::kWrite:
out << "writeonly ";
break;
case core::Access::kReadWrite: {
if (version_.IsES()) {
// ESSL 3.1 SPEC (chapter 4.9, Memory Access Qualifiers):
// Except for image variables qualified with the format qualifiers r32f,
// r32i, and r32ui, image variables must specify either memory qualifier
// readonly or the memory qualifier writeonly.
switch (storage->TexelFormat()) {
case core::TexelFormat::kR32Float:
case core::TexelFormat::kR32Sint:
case core::TexelFormat::kR32Uint:
break;
default:
TINT_UNREACHABLE() << "invalid texel format for read-write";
}
}
break;
}
default:
TINT_UNREACHABLE() << "invalid storage access";
}
}
auto* subtype = sampled ? sampled->Type()
: storage ? storage->Type()
: ms ? ms->Type()
: nullptr;
if (subtype) {
tint::Switch(
subtype, //
[&](const core::type::F32*) {}, //
[&](const core::type::I32*) { out << "i"; },
[&](const core::type::U32*) { out << "u"; }, //
TINT_ICE_ON_NO_MATCH);
}
out << (storage ? "image" : "sampler");
switch (t->Dim()) {
case core::type::TextureDimension::k2d:
out << "2D";
if (ms || depth_ms) {
out << "MS";
}
break;
case core::type::TextureDimension::k2dArray:
out << "2D";
if (ms) {
out << "MS";
}
out << "Array";
break;
case core::type::TextureDimension::k3d:
out << "3D";
break;
case core::type::TextureDimension::kCube:
out << "Cube";
break;
case core::type::TextureDimension::kCubeArray:
out << "CubeArray";
break;
default:
TINT_UNREACHABLE() << "unknown texture dimension: " << t->Dim();
}
if (t->Is<core::type::DepthTexture>()) {
out << "Shadow";
}
}
/// Emit a return instruction
/// @param r the return instruction
void EmitReturn(const core::ir::Return* r) {
// If this return has no arguments and the current block is for the function which is
// being returned, skip the return.
if (current_block_ == current_function_->Block() && r->Args().IsEmpty()) {
return;
}
auto out = Line();
out << "return";
if (!r->Args().IsEmpty()) {
out << " ";
EmitValue(out, r->Args().Front());
}
out << ";";
}
void EmitVar(StringStream& out, const core::ir::Var* var) {
auto* ptr = var->Result(0)->Type()->As<core::type::Pointer>();
auto space = ptr->AddressSpace();
EmitTypeAndName(out, var->Result(0)->Type(), NameOf(var->Result(0)));
if (var->Initializer()) {
out << " = ";
EmitValue(out, var->Initializer());
} else if (space == core::AddressSpace::kPrivate ||
space == core::AddressSpace::kFunction) {
TINT_ASSERT(ptr);
out << " = ";
EmitZeroValue(out, ptr->UnwrapPtr());
}
out << ";";
}
void EmitGlobalVar(core::ir::Var* var) {
auto* ptr = var->Result(0)->Type()->As<core::type::Pointer>();
auto space = ptr->AddressSpace();
switch (space) {
case core::AddressSpace::kStorage:
EmitStorageVar(var);
break;
case core::AddressSpace::kUniform:
EmitUniformVar(var);
break;
case core::AddressSpace::kWorkgroup:
EmitWorkgroupVar(var);
break;
case core::AddressSpace::kHandle:
EmitHandleVar(var);
break;
case core::AddressSpace::kPushConstant:
EmitPushConstantVar(var);
break;
case core::AddressSpace::kIn:
case core::AddressSpace::kOut:
EmitIOVar(var);
break;
case core::AddressSpace::kPixelLocal:
TINT_UNREACHABLE() << "PixelLocal not supported";
default: {
auto out = Line();
EmitVar(out, var);
break;
}
}
}
void EmitStorageVar(core::ir::Var* var) {
const auto& bp = var->BindingPoint();
TINT_ASSERT(bp.has_value());
EmitLayoutBinding(Line(), bp.value(), std::nullopt, {LayoutFormat::kStd430});
auto* ptr = var->Result(0)->Type()->As<core::type::Pointer>();
EmitVarStruct("buffer", NameOf(var->Result(0)), "ssbo",
ptr->UnwrapPtr()->As<core::type::Struct>());
}
void EmitUniformVar(core::ir::Var* var) {
const auto& bp = var->BindingPoint();
TINT_ASSERT(bp.has_value());
EmitLayoutBinding(Line(), bp.value(), std::nullopt, {LayoutFormat::kStd140});
auto* ptr = var->Result(0)->Type()->As<core::type::Pointer>();
EmitVarStruct("uniform", NameOf(var->Result(0)), "ubo",
ptr->UnwrapPtr()->As<core::type::Struct>());
}
void EmitWorkgroupVar(core::ir::Var* var) {
auto out = Line();
out << "shared ";
EmitVar(out, var);
}
void EmitHandleVar(core::ir::Var* var) {
auto* ptr = var->Result(0)->Type()->As<core::type::Pointer>();
// GLSL ignores sampler variables.
if (ptr->UnwrapPtr()->Is<core::type::Sampler>()) {
return;
}
auto out = Line();
if (auto* storage = ptr->UnwrapPtr()->As<core::type::StorageTexture>()) {
const auto& bp = var->BindingPoint();
TINT_ASSERT(bp.has_value());
EmitLayoutBinding(out, bp.value(), {storage->TexelFormat()}, std::nullopt);
out << " ";
}
EmitVar(out, var);
}
void EmitPushConstantVar(core::ir::Var* var) {
auto out = Line();
EmitLayoutLocation(out, {0}, std::nullopt);
EmitVar(out, var);
}
void EmitIOVar(core::ir::Var* var) {
auto& attrs = var->Attributes();
if (attrs.builtin.has_value()) {
if (version_.IsES() && (attrs.builtin == tint::core::BuiltinValue::kSampleIndex ||
attrs.builtin == tint::core::BuiltinValue::kSampleMask)) {
EmitExtension(kOESSampleVariables);
}
// Do not emit builtin (gl_) variables.
return;
}
auto out = Line();
EmitLayoutLocation(out, attrs.location, attrs.blend_src);
if (attrs.interpolation.has_value()) {
EmitInterpolation(out, attrs.interpolation.value());
}
EmitVar(out, var);
}
void EmitVarStruct(std::string_view kind,
std::string_view name,
std::string_view type_suffix,
const core::type::Struct* str) {
TINT_ASSERT(str);
Line() << kind << " " << UniqueIdentifier(StructName(str)) << "_" << type_suffix << " {";
{
ScopedIndent si(current_buffer_);
for (auto* mem : str->Members()) {
auto out = Line();
EmitTypeAndName(out, mem->Type(), mem->Name().Name());
out << ";";
}
}
Line() << "} " << name << ";";
}
void EmitLayoutLocation(StringStream& out,
std::optional<uint32_t> location,
std::optional<uint32_t> blend_src) {
if (location.has_value()) {
out << "layout(location = " << location.value();
if (blend_src.has_value()) {
EmitExtension(kEXTBlendFuncExtended);
out << ", index = " << blend_src.value();
}
out << ") ";
}
}
void EmitLayoutBinding(StringStream& out,
const tint::BindingPoint& bp,
std::optional<core::TexelFormat> texel_format,
std::optional<LayoutFormat> layout_format) {
TINT_ASSERT(!(texel_format.has_value() && layout_format.has_value()));
out << "layout(binding = " << bp.binding;
if (layout_format.has_value()) {
out << ", ";
switch (layout_format.value()) {
case LayoutFormat::kStd140:
out << "std140";
break;
case LayoutFormat::kStd430:
out << "std430";
break;
}
}
if (texel_format.has_value()) {
out << ", ";
switch (texel_format.value()) {
case core::TexelFormat::kBgra8Unorm:
TINT_ICE() << "bgra8unorm should have been polyfilled to rgba8unorm";
case core::TexelFormat::kR32Uint:
out << "r32ui";
break;
case core::TexelFormat::kR32Sint:
out << "r32i";
break;
case core::TexelFormat::kR32Float:
out << "r32f";
break;
case core::TexelFormat::kRgba8Unorm:
out << "rgba8";
break;
case core::TexelFormat::kRgba8Snorm:
out << "rgba8_snorm";
break;
case core::TexelFormat::kRgba8Uint:
out << "rgba8ui";
break;
case core::TexelFormat::kRgba8Sint:
out << "rgba8i";
break;
case core::TexelFormat::kRg32Uint:
out << "rg32ui";
break;
case core::TexelFormat::kRg32Sint:
out << "rg32i";
break;
case core::TexelFormat::kRg32Float:
out << "rg32f";
break;
case core::TexelFormat::kRgba16Uint:
out << "rgba16ui";
break;
case core::TexelFormat::kRgba16Sint:
out << "rgba16i";
break;
case core::TexelFormat::kRgba16Float:
out << "rgba16f";
break;
case core::TexelFormat::kRgba32Uint:
out << "rgba32ui";
break;
case core::TexelFormat::kRgba32Sint:
out << "rgba32i";
break;
case core::TexelFormat::kRgba32Float:
out << "rgba32f";
break;
case core::TexelFormat::kR8Unorm:
out << "r8";
break;
case core::TexelFormat::kUndefined:
TINT_UNREACHABLE() << "invalid texel format";
}
}
out << ")";
}
void EmitInterpolation(StringStream& out, const core::Interpolation& interp) {
switch (interp.type) {
case core::InterpolationType::kPerspective:
case core::InterpolationType::kLinear:
case core::InterpolationType::kUndefined:
break;
case core::InterpolationType::kFlat:
out << "flat ";
break;
}
switch (interp.sampling) {
case core::InterpolationSampling::kCentroid:
out << "centroid ";
break;
case core::InterpolationSampling::kSample:
case core::InterpolationSampling::kCenter:
case core::InterpolationSampling::kFirst:
case core::InterpolationSampling::kEither:
case core::InterpolationSampling::kUndefined:
break;
}
}
/// Emits the zero value for the given type
/// @param out the stream to emit too
/// @param ty the type
void EmitZeroValue(StringStream& out, const core::type::Type* ty) {
EmitConstant(out, ir_.constant_values.Zero(ty));
}
void EmitValue(StringStream& out, const core::ir::Value* v) {
tint::Switch(
v, //
[&](const core::ir::Constant* c) { EmitConstant(out, c); },
[&](const core::ir::InstructionResult* r) {
tint::Switch(
r->Instruction(), //
[&](const core::ir::Access* a) { EmitAccess(out, a); },
[&](const core::ir::Construct* c) { EmitConstruct(out, c); },
[&](const core::ir::Convert* c) { EmitConvert(out, c); }, //
[&](const core::ir::CoreBinary* b) { EmitBinary(out, b); },
[&](const core::ir::CoreBuiltinCall* c) { EmitCoreBuiltinCall(out, c); },
[&](const core::ir::CoreUnary* u) { EmitUnary(out, u); },
[&](const core::ir::Let* l) { out << NameOf(l->Result(0)); },
[&](const core::ir::Load* l) { EmitLoad(out, l); },
[&](const core::ir::LoadVectorElement* l) { EmitLoadVectorElement(out, l); },
[&](const core::ir::Store* s) { EmitStore(s); },
[&](const core::ir::Swizzle* s) { EmitSwizzle(out, s); }, //
[&](const core::ir::UserCall* c) { EmitUserCall(out, c); },
[&](const core::ir::Var* var) { out << NameOf(var->Result(0)); },
[&](const glsl::ir::BuiltinCall* c) { EmitGlslBuiltinCall(out, c); }, //
[&](const glsl::ir::MemberBuiltinCall* mbc) {
EmitGlslMemberBuiltinCall(out, mbc);
},
[&](const glsl::ir::Ternary* t) { EmitTernary(out, t); }, //
TINT_ICE_ON_NO_MATCH);
},
[&](const core::ir::FunctionParam* p) { out << NameOf(p); }, //
TINT_ICE_ON_NO_MATCH);
}
void EmitGlslMemberBuiltinCall(StringStream& out, const glsl::ir::MemberBuiltinCall* c) {
EmitValue(out, c->Object());
out << "." << c->Func() << "(";
bool needs_comma = false;
for (const auto* arg : c->Args()) {
if (needs_comma) {
out << ", ";
}
EmitValue(out, arg);
needs_comma = true;
}
out << ")";
}
bool RequiresEXTTextureShadowLod(glsl::BuiltinFn fn) {
return fn == glsl::BuiltinFn::kExtTextureLod || fn == glsl::BuiltinFn::kExtTextureLodOffset;
}
glsl::BuiltinFn EXTToNonEXT(glsl::BuiltinFn fn) {
switch (fn) {
case glsl::BuiltinFn::kExtTextureLod:
return glsl::BuiltinFn::kTextureLod;
case glsl::BuiltinFn::kExtTextureLodOffset:
return glsl::BuiltinFn::kTextureLodOffset;
default:
TINT_UNREACHABLE() << "invalid function for conversion: " << fn;
}
}
void EmitGlslBuiltinCall(StringStream& out, const glsl::ir::BuiltinCall* c) {
// The atomic subtract is an add in GLSL. If the value is a u32, it just negates the u32 and
// GLSL handles it. We don't have u32 negation in the IR, so fake it in the printer.
if (c->Func() == glsl::BuiltinFn::kAtomicSub) {
out << "atomicAdd";
{
ScopedParen sp(out);
EmitValue(out, c->Args()[0]);
out << ", -";
{
ScopedParen argSP(out);
EmitValue(out, c->Args()[1]);
}
}
return;
}
auto fn = c->Func();
if (RequiresEXTTextureShadowLod(fn)) {
EmitExtension(kEXTTextureShadowLod);
fn = EXTToNonEXT(fn);
}
out << fn << "(";
bool needs_comma = false;
for (const auto* arg : c->Args()) {
if (needs_comma) {
out << ", ";
}
EmitValue(out, arg);
needs_comma = true;
}
out << ")";
}
void EmitTernary(StringStream& out, const glsl::ir::Ternary* t) {
out << "((";
EmitValue(out, t->Cmp());
out << ") ? (";
EmitValue(out, t->True());
out << ") : (";
EmitValue(out, t->False());
out << "))";
return;
}
/// Emit a convert instruction
void EmitConvert(StringStream& out, const core::ir::Convert* c) {
EmitType(out, c->Result(0)->Type());
out << "(";
EmitValue(out, c->Operand(0));
out << ")";
}
/// Emit a constructor
void EmitConstruct(StringStream& out, const core::ir::Construct* c) {
if (c->Args().IsEmpty()) {
EmitZeroValue(out, c->Result(0)->Type());
return;
}
auto emit_args = [&]() {
out << "(";
size_t i = 0;
for (auto* arg : c->Args()) {
if (i > 0) {
out << ", ";
}
EmitValue(out, arg);
i++;
}
out << ")";
};
Switch(
c->Result(0)->Type(),
[&](const core::type::Struct* struct_ty) {
EmitStructType(struct_ty);
out << StructName(struct_ty);
emit_args();
},
[&](Default) {
EmitType(out, c->Result(0)->Type());
emit_args();
});
}
/// Emit Load
/// @param out the output stream to write to
/// @param load the load
void EmitLoad(StringStream& out, const core::ir::Load* load) { EmitValue(out, load->From()); }
/// Emit a store
void EmitStore(const core::ir::Store* s) {
auto out = Line();
EmitValue(out, s->To());
out << " = ";
EmitValue(out, s->From());
out << ";";
}
void EmitUnary(StringStream& out, const core::ir::CoreUnary* u) {
switch (u->Op()) {
case core::UnaryOp::kNegation:
out << "-";
break;
case core::UnaryOp::kComplement:
out << "~";
break;
case core::UnaryOp::kNot:
if (u->Val()->Type()->Is<core::type::Scalar>()) {
out << "!";
} else {
out << "not";
}
break;
default:
TINT_UNIMPLEMENTED() << u->Op();
}
out << "(";
EmitValue(out, u->Val());
out << ")";
}
/// Emit a binary instruction
/// @param b the binary instruction
void EmitBinary(StringStream& out, const core::ir::CoreBinary* b) {
auto kind = [&] {
switch (b->Op()) {
case core::BinaryOp::kAdd:
return "+";
case core::BinaryOp::kSubtract:
return "-";
case core::BinaryOp::kMultiply:
return "*";
case core::BinaryOp::kDivide:
return "/";
case core::BinaryOp::kModulo:
return "%";
case core::BinaryOp::kAnd:
return "&";
case core::BinaryOp::kOr:
return "|";
case core::BinaryOp::kXor:
return "^";
case core::BinaryOp::kEqual:
return "==";
case core::BinaryOp::kNotEqual:
return "!=";
case core::BinaryOp::kLessThan:
return "<";
case core::BinaryOp::kGreaterThan:
return ">";
case core::BinaryOp::kLessThanEqual:
return "<=";
case core::BinaryOp::kGreaterThanEqual:
return ">=";
case core::BinaryOp::kShiftLeft:
return "<<";
case core::BinaryOp::kShiftRight:
return ">>";
case core::BinaryOp::kLogicalAnd:
case core::BinaryOp::kLogicalOr:
// These should have been replaced by if statements as GLSL is not
// short-circuting.
TINT_UNREACHABLE() << "logical and/or should not be present";
}
return "<error>";
};
ScopedParen sp(out);
EmitValue(out, b->LHS());
out << " " << kind() << " ";
EmitValue(out, b->RHS());
}
void EmitCoreBuiltinCall(StringStream& out, const core::ir::CoreBuiltinCall* c) {
EmitCoreBuiltinName(out, c->Func());
ScopedParen sp(out);
size_t i = 0;
for (const auto* arg : c->Args()) {
if (i > 0) {
out << ", ";
}
++i;
EmitValue(out, arg);
}
}
void EmitCoreBuiltinName(StringStream& out, core::BuiltinFn func) {
switch (func) {
case core::BuiltinFn::kAbs:
case core::BuiltinFn::kAcos:
case core::BuiltinFn::kAcosh:
case core::BuiltinFn::kAsin:
case core::BuiltinFn::kAsinh:
case core::BuiltinFn::kAtan:
case core::BuiltinFn::kAtanh:
case core::BuiltinFn::kAtomicAdd:
case core::BuiltinFn::kAtomicAnd:
case core::BuiltinFn::kAtomicExchange:
case core::BuiltinFn::kAtomicMax:
case core::BuiltinFn::kAtomicMin:
case core::BuiltinFn::kAtomicOr:
case core::BuiltinFn::kAtomicXor:
case core::BuiltinFn::kCeil:
case core::BuiltinFn::kClamp:
case core::BuiltinFn::kCos:
case core::BuiltinFn::kCosh:
case core::BuiltinFn::kCross:
case core::BuiltinFn::kDegrees:
case core::BuiltinFn::kDeterminant:
case core::BuiltinFn::kDistance:
case core::BuiltinFn::kExp:
case core::BuiltinFn::kExp2:
case core::BuiltinFn::kFloor:
case core::BuiltinFn::kFrexp:
case core::BuiltinFn::kLdexp:
case core::BuiltinFn::kLength:
case core::BuiltinFn::kLog:
case core::BuiltinFn::kLog2:
case core::BuiltinFn::kMax:
case core::BuiltinFn::kMin:
case core::BuiltinFn::kNormalize:
case core::BuiltinFn::kPow:
case core::BuiltinFn::kRadians:
case core::BuiltinFn::kReflect:
case core::BuiltinFn::kRefract:
case core::BuiltinFn::kRound:
case core::BuiltinFn::kSign:
case core::BuiltinFn::kSin:
case core::BuiltinFn::kSinh:
case core::BuiltinFn::kSqrt:
case core::BuiltinFn::kStep:
case core::BuiltinFn::kTan:
case core::BuiltinFn::kTanh:
case core::BuiltinFn::kTranspose:
case core::BuiltinFn::kTrunc:
out << func;
break;
case core::BuiltinFn::kAtan2:
out << "atan";
break;
case core::BuiltinFn::kAtomicStore:
// GLSL does not have an atomicStore, so we emulate it with
// atomicExchange.
out << "atomicExchange";
break;
case core::BuiltinFn::kDpdx:
out << "dFdx";
break;
case core::BuiltinFn::kDpdxCoarse:
out << "dFdx";
if (version_.IsDesktop()) {
out << "Coarse";
}
break;
case core::BuiltinFn::kDpdxFine:
out << "dFdx";
if (version_.IsDesktop()) {
out << "Fine";
}
break;
case core::BuiltinFn::kDpdy:
out << "dFdy";
break;
case core::BuiltinFn::kDpdyCoarse:
out << "dFdy";
if (version_.IsDesktop()) {
out << "Coarse";
}
break;
case core::BuiltinFn::kDpdyFine:
out << "dFdy";
if (version_.IsDesktop()) {
out << "Fine";
}
break;
case core::BuiltinFn::kFaceForward:
out << "faceforward";
break;
case core::BuiltinFn::kFract:
out << "fract";
break;
case core::BuiltinFn::kFma:
out << "fma";
break;
case core::BuiltinFn::kFwidth:
case core::BuiltinFn::kFwidthCoarse:
case core::BuiltinFn::kFwidthFine:
out << "fwidth";
break;
case core::BuiltinFn::kInverseSqrt:
out << "inversesqrt";
break;
case core::BuiltinFn::kMix:
out << "mix";
break;
case core::BuiltinFn::kPack2X16Float:
out << "packHalf2x16";
break;
case core::BuiltinFn::kPack2X16Snorm:
out << "packSnorm2x16";
break;
case core::BuiltinFn::kPack2X16Unorm:
out << "packUnorm2x16";
break;
case core::BuiltinFn::kPack4X8Snorm:
out << "packSnorm4x8";
break;
case core::BuiltinFn::kPack4X8Unorm:
out << "packUnorm4x8";
break;
case core::BuiltinFn::kReverseBits:
out << "bitfieldReverse";
break;
case core::BuiltinFn::kSmoothstep:
out << "smoothstep";
break;
case core::BuiltinFn::kUnpack2X16Float:
out << "unpackHalf2x16";
break;
case core::BuiltinFn::kUnpack2X16Snorm:
out << "unpackSnorm2x16";
break;
case core::BuiltinFn::kUnpack2X16Unorm:
out << "unpackUnorm2x16";
break;
case core::BuiltinFn::kUnpack4X8Snorm:
out << "unpackSnorm4x8";
break;
case core::BuiltinFn::kUnpack4X8Unorm:
out << "unpackUnorm4x8";
break;
default:
TINT_UNREACHABLE() << "unhandled core builtin: " << func;
}
}
/// Emits a user call instruction
void EmitUserCall(StringStream& out, const core::ir::UserCall* c) {
out << NameOf(c->Target()) << "(";
size_t i = 0;
for (const auto* arg : c->Args()) {
if (i > 0) {
out << ", ";
}
++i;
EmitValue(out, arg);
}
out << ")";
}
void EmitConstant(StringStream& out, const core::ir::Constant* c) {
EmitConstant(out, c->Value());
}
void EmitConstant(StringStream& out, const core::constant::Value* c) {
tint::Switch(
c->Type(), //
[&](const core::type::Array* ary) { EmitConstantArray(out, ary, c); },
[&](const core::type::Bool*) { out << (c->ValueAs<AInt>() ? "true" : "false"); },
[&](const core::type::I32*) { PrintI32(out, c->ValueAs<i32>()); },
[&](const core::type::U32*) { out << c->ValueAs<AInt>() << "u"; },
[&](const core::type::F32*) { PrintF32(out, c->ValueAs<f32>()); },
[&](const core::type::F16*) { PrintF16(out, c->ValueAs<f16>()); },
[&](const core::type::Vector* v) { EmitConstantVector(out, v, c); },
[&](const core::type::Matrix* m) { EmitConstantMatrix(out, m, c); },
[&](const core::type::Struct* s) { EmitConstantStruct(out, s, c); },
TINT_ICE_ON_NO_MATCH);
}
void EmitConstantStruct(StringStream& out,
const core::type::Struct* s,
const core::constant::Value* c) {
EmitType(out, s);
ScopedParen sp(out);
for (size_t i = 0; i < s->Members().Length(); ++i) {
if (i > 0) {
out << ", ";
}
EmitConstant(out, c->Index(i));
}
}
void EmitConstantVector(StringStream& out,
const core::type::Vector* v,
const core::constant::Value* c) {
EmitType(out, v);
ScopedParen sp(out);
if (auto* splat = c->As<core::constant::Splat>()) {
EmitConstant(out, splat->el);
return;
}
for (size_t i = 0; i < v->Width(); ++i) {
if (i > 0) {
out << ", ";
}
EmitConstant(out, c->Index(i));
}
}
void EmitConstantMatrix(StringStream& out,
const core::type::Matrix* m,
const core::constant::Value* c) {
EmitType(out, m);
ScopedParen sp(out);
for (size_t col_idx = 0; col_idx < m->Columns(); ++col_idx) {
if (col_idx > 0) {
out << ", ";
}
EmitConstant(out, c->Index(col_idx));
}
}
void EmitConstantArray(StringStream& out,
const core::type::Array* ary,
const core::constant::Value* c) {
EmitType(out, ary);
ScopedParen sp(out);
auto count = ary->ConstantCount();
TINT_ASSERT(count.has_value());
for (size_t i = 0; i < count; ++i) {
if (i > 0) {
out << ", ";
}
EmitConstant(out, c->Index(i));
}
}
/// Emit an unreachable instruction
void EmitUnreachable() { Line() << "/* unreachable */"; }
};
} // namespace
Result<std::string> Print(core::ir::Module& module, const Version& version) {
return Printer{module, version}.Generate();
}
} // namespace tint::glsl::writer