================ @@ -0,0 +1,194 @@ +//===- RootSignatureMetadata.h - HLSL Root Signature helpers --------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +/// +/// \file This file implements a library for working with HLSL Root Signatures +/// and their metadata representation. +/// +//===----------------------------------------------------------------------===// + +#include "llvm/Frontend/HLSL/RootSignatureMetadata.h" +#include "llvm/IR/IRBuilder.h" +#include "llvm/IR/Metadata.h" +#include "llvm/Support/ScopedPrinter.h" + +namespace llvm { +namespace hlsl { +namespace rootsig { + +static const EnumEntry<dxil::ResourceClass> ResourceClassNames[] = { + {"CBV", dxil::ResourceClass::CBuffer}, + {"SRV", dxil::ResourceClass::SRV}, + {"UAV", dxil::ResourceClass::UAV}, + {"Sampler", dxil::ResourceClass::Sampler}, +}; + +static std::optional<StringRef> getResourceName(dxil::ResourceClass Class) { + for (const auto &ClassEnum : ResourceClassNames) + if (ClassEnum.Value == Class) + return ClassEnum.Name; + return std::nullopt; +} + +namespace { + +// We use the OverloadVisit with std::visit to ensure the compiler catches if a +// new RootElement variant type is added but it's metadata generation isn't +// handled. +template <class... Ts> struct OverloadedVisit : Ts... { + using Ts::operator()...; +}; +template <class... Ts> OverloadedVisit(Ts...) -> OverloadedVisit<Ts...>; + +} // namespace + +MDNode *MetadataBuilder::BuildRootSignature() { + const auto Visitor = OverloadedVisit{ + [this](const dxbc::RootFlags &Flags) -> MDNode * { + return BuildRootFlags(Flags); + }, + [this](const RootConstants &Constants) -> MDNode * { + return BuildRootConstants(Constants); + }, + [this](const RootDescriptor &Descriptor) -> MDNode * { + return BuildRootDescriptor(Descriptor); + }, + [this](const DescriptorTableClause &Clause) -> MDNode * { + return BuildDescriptorTableClause(Clause); + }, + [this](const DescriptorTable &Table) -> MDNode * { + return BuildDescriptorTable(Table); + }, + [this](const StaticSampler &Sampler) -> MDNode * { + return BuildStaticSampler(Sampler); + }, + }; + + for (const RootElement &Element : Elements) { + MDNode *ElementMD = std::visit(Visitor, Element); + assert(ElementMD != nullptr && + "Root Element must be initialized and validated"); + GeneratedMetadata.push_back(ElementMD); + } + + return MDNode::get(Ctx, GeneratedMetadata); +} + +MDNode *MetadataBuilder::BuildRootFlags(const dxbc::RootFlags &Flags) { + IRBuilder<> Builder(Ctx); + Metadata *Operands[] = { + MDString::get(Ctx, "RootFlags"), + ConstantAsMetadata::get(Builder.getInt32(llvm::to_underlying(Flags))), + }; + return MDNode::get(Ctx, Operands); +} + +MDNode *MetadataBuilder::BuildRootConstants(const RootConstants &Constants) { + IRBuilder<> Builder(Ctx); + Metadata *Operands[] = { + MDString::get(Ctx, "RootConstants"), + ConstantAsMetadata::get( + Builder.getInt32(llvm::to_underlying(Constants.Visibility))), + ConstantAsMetadata::get(Builder.getInt32(Constants.Reg.Number)), + ConstantAsMetadata::get(Builder.getInt32(Constants.Space)), + ConstantAsMetadata::get(Builder.getInt32(Constants.Num32BitConstants)), + }; + return MDNode::get(Ctx, Operands); +} + +MDNode *MetadataBuilder::BuildRootDescriptor(const RootDescriptor &Descriptor) { + IRBuilder<> Builder(Ctx); + std::optional<StringRef> ResName = getResourceName( + dxil::ResourceClass(llvm::to_underlying(Descriptor.Type))); + assert(ResName && "Provided an invalid Resource Class"); + llvm::SmallString<7> Name({"Root", *ResName}); ---------------- alsepkow wrote:
Is 7 a sufficient size here? Copilot tells me this class uses that size for its default stack allocation size and falls back to the heap if its larger. Do you think it would be worth it to just add a bigger buffer to that to avoid future issues? 7 seems really small to me. https://github.com/llvm/llvm-project/pull/146124 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
