// Copyright 2021 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <algorithm>
#include <string>
#include <tuple>
#include <type_traits>
#include "common/div_ceil.h"
#include "common/settings.h"
#include "shader_recompiler/backend/glsl/emit_glsl.h"
#include "shader_recompiler/backend/glsl/emit_glsl_instructions.h"
#include "shader_recompiler/backend/glsl/glsl_emit_context.h"
#include "shader_recompiler/frontend/ir/ir_emitter.h"
namespace Shader::Backend::GLSL {
namespace {
template <class Func>
struct FuncTraits {};
template <class ReturnType_, class... Args>
struct FuncTraits<ReturnType_ (*)(Args...)> {
using ReturnType = ReturnType_;
static constexpr size_t NUM_ARGS = sizeof...(Args);
template <size_t I>
using ArgType = std::tuple_element_t<I, std::tuple<Args...>>;
};
template <auto func, typename... Args>
void SetDefinition(EmitContext& ctx, IR::Inst* inst, Args... args) {
inst->SetDefinition<Id>(func(ctx, std::forward<Args>(args)...));
}
template <typename ArgType>
auto Arg(EmitContext& ctx, const IR::Value& arg) {
if constexpr (std::is_same_v<ArgType, std::string_view>) {
return ctx.var_alloc.Consume(arg);
} else if constexpr (std::is_same_v<ArgType, const IR::Value&>) {
return arg;
} else if constexpr (std::is_same_v<ArgType, u32>) {
return arg.U32();
} else if constexpr (std::is_same_v<ArgType, IR::Attribute>) {
return arg.Attribute();
} else if constexpr (std::is_same_v<ArgType, IR::Patch>) {
return arg.Patch();
} else if constexpr (std::is_same_v<ArgType, IR::Reg>) {
return arg.Reg();
}
}
template <auto func, bool is_first_arg_inst, size_t... I>
void Invoke(EmitContext& ctx, IR::Inst* inst, std::index_sequence<I...>) {
using Traits = FuncTraits<decltype(func)>;
if constexpr (std::is_same_v<typename Traits::ReturnType, Id>) {
if constexpr (is_first_arg_inst) {
SetDefinition<func>(
ctx, inst, *inst,
Arg<typename Traits::template ArgType<I + 2>>(ctx, inst->Arg(I))...);
} else {
SetDefinition<func>(
ctx, inst, Arg<typename Traits::template ArgType<I + 1>>(ctx, inst->Arg(I))...);
}
} else {
if constexpr (is_first_arg_inst) {
func(ctx, *inst, Arg<typename Traits::template ArgType<I + 2>>(ctx, inst->Arg(I))...);
} else {
func(ctx, Arg<typename Traits::template ArgType<I + 1>>(ctx, inst->Arg(I))...);
}
}
}
template <auto func>
void Invoke(EmitContext& ctx, IR::Inst* inst) {
using Traits = FuncTraits<decltype(func)>;
static_assert(Traits::NUM_ARGS >= 1, "Insufficient arguments");
if constexpr (Traits::NUM_ARGS == 1) {
Invoke<func, false>(ctx, inst, std::make_index_sequence<0>{});
} else {
using FirstArgType = typename Traits::template ArgType<1>;
static constexpr bool is_first_arg_inst = std::is_same_v<FirstArgType, IR::Inst&>;
using Indices = std::make_index_sequence<Traits::NUM_ARGS - (is_first_arg_inst ? 2 : 1)>;
Invoke<func, is_first_arg_inst>(ctx, inst, Indices{});
}
}
void EmitInst(EmitContext& ctx, IR::Inst* inst) {
switch (inst->GetOpcode()) {
#define OPCODE(name, result_type, ...) \
case IR::Opcode::name: \
return Invoke<&Emit##name>(ctx, inst);
#include "shader_recompiler/frontend/ir/opcodes.inc"
#undef OPCODE
}
throw LogicError("Invalid opcode {}", inst->GetOpcode());
}
bool IsReference(IR::Inst& inst) {
return inst.GetOpcode() == IR::Opcode::Reference;
}
void PrecolorInst(IR::Inst& phi) {
// Insert phi moves before references to avoid overwritting other phis
const size_t num_args{phi.NumArgs()};
for (size_t i = 0; i < num_args; ++i) {
IR::Block& phi_block{*phi.PhiBlock(i)};
auto it{std::find_if_not(phi_block.rbegin(), phi_block.rend(), IsReference).base()};
IR::IREmitter ir{phi_block, it};
const IR::Value arg{phi.Arg(i)};
if (arg.IsImmediate()) {
ir.PhiMove(phi, arg);
} else {
ir.PhiMove(phi, IR::Value{arg.InstRecursive()});
}
}
for (size_t i = 0; i < num_args; ++i) {
IR::IREmitter{*phi.PhiBlock(i)}.Reference(IR::Value{&phi});
}
}
void Precolor(const IR::Program& program) {
for (IR::Block* const block : program.blocks) {
for (IR::Inst& phi : block->Instructions()) {
if (!IR::IsPhi(phi)) {
break;
}
PrecolorInst(phi);
}
}
}
void EmitCode(EmitContext& ctx, const IR::Program& program) {
for (const IR::AbstractSyntaxNode& node : program.syntax_list) {
switch (node.type) {
case IR::AbstractSyntaxNode::Type::Block:
for (IR::Inst& inst : node.data.block->Instructions()) {
EmitInst(ctx, &inst);
}
break;
case IR::AbstractSyntaxNode::Type::If:
ctx.Add("if({}){{", ctx.var_alloc.Consume(node.data.if_node.cond));
break;
case IR::AbstractSyntaxNode::Type::EndIf:
ctx.Add("}}");
break;
case IR::AbstractSyntaxNode::Type::Break:
if (node.data.break_node.cond.IsImmediate()) {
if (node.data.break_node.cond.U1()) {
ctx.Add("break;");
}
} else {
ctx.Add("if({}){{break;}}", ctx.var_alloc.Consume(node.data.break_node.cond));
}
break;
case IR::AbstractSyntaxNode::Type::Return:
case IR::AbstractSyntaxNode::Type::Unreachable:
ctx.Add("return;");
break;
case IR::AbstractSyntaxNode::Type::Loop:
ctx.Add("for(;;){{");
break;
case IR::AbstractSyntaxNode::Type::Repeat:
if (Settings::values.disable_shader_loop_safety_checks) {
ctx.Add("if(!{}){{break;}}}}", ctx.var_alloc.Consume(node.data.repeat.cond));
} else {
ctx.Add("if(--loop{}<0 || !{}){{break;}}}}", ctx.num_safety_loop_vars++,
ctx.var_alloc.Consume(node.data.repeat.cond));
}
break;
default:
throw NotImplementedException("AbstractSyntaxNode Type {}", node.type);
}
}
}
std::string GlslVersionSpecifier(const EmitContext& ctx) {
if (ctx.uses_y_direction || ctx.info.stores.Legacy() || ctx.info.loads.Legacy()) {
return " compatibility";
}
return "";
}
bool IsPreciseType(GlslVarType type) {
switch (type) {
case GlslVarType::PrecF32:
case GlslVarType::PrecF64:
return true;
default:
return false;
}
}
void DefineVariables(const EmitContext& ctx, std::string& header) {
for (u32 i = 0; i < static_cast<u32>(GlslVarType::Void); ++i) {
const auto type{static_cast<GlslVarType>(i)};
const auto& tracker{ctx.var_alloc.GetUseTracker(type)};
const auto type_name{ctx.var_alloc.GetGlslType(type)};
const bool has_precise_bug{ctx.stage == Stage::Fragment && ctx.profile.has_gl_precise_bug};
const auto precise{!has_precise_bug && IsPreciseType(type) ? "precise " : ""};
// Temps/return types that are never used are stored at index 0
if (tracker.uses_temp) {
header += fmt::format("{}{} t{}={}(0);", precise, type_name,
ctx.var_alloc.Representation(0, type), type_name);
}
for (u32 index = 0; index < tracker.num_used; ++index) {
header += fmt::format("{}{} {}={}(0);", precise, type_name,
ctx.var_alloc.Representation(index, type), type_name);
}
}
for (u32 i = 0; i < ctx.num_safety_loop_vars; ++i) {
header += fmt::format("int loop{}=0x2000;", i);
}
}
} // Anonymous namespace
std::string EmitGLSL(const Profile& profile, const RuntimeInfo& runtime_info, IR::Program& program,
Bindings& bindings) {
EmitContext ctx{program, bindings, profile, runtime_info};
Precolor(program);
EmitCode(ctx, program);
const std::string version{fmt::format("#version 450{}\n", GlslVersionSpecifier(ctx))};
ctx.header.insert(0, version);
if (program.shared_memory_size > 0) {
const auto requested_size{program.shared_memory_size};
const auto max_size{profile.gl_max_compute_smem_size};
const bool needs_clamp{requested_size > max_size};
if (needs_clamp) {
LOG_WARNING(Shader_GLSL, "Requested shared memory size ({}) exceeds device limit ({})",
requested_size, max_size);
}
const auto smem_size{needs_clamp ? max_size : requested_size};
ctx.header += fmt::format("shared uint smem[{}];", Common::DivCeil(smem_size, 4U));
}
ctx.header += "void main(){\n";
if (program.local_memory_size > 0) {
ctx.header += fmt::format("uint lmem[{}];", Common::DivCeil(program.local_memory_size, 4U));
}
DefineVariables(ctx, ctx.header);
if (ctx.uses_cc_carry) {
ctx.header += "uint carry;";
}
if (program.info.uses_subgroup_shuffles) {
ctx.header += "bool shfl_in_bounds;";
}
ctx.code.insert(0, ctx.header);
ctx.code += '}';
return ctx.code;
}
} // namespace Shader::Backend::GLSL
