lib/DXIL/DxilSemantic.cpp

///////////////////////////////////////////////////////////////////////////////
//                                                                           //
// DxilSemantic.cpp                                                          //
// Copyright (C) Microsoft Corporation. All rights reserved.                 //
// This file is distributed under the University of Illinois Open Source     //
// License. See LICENSE.TXT for details.                                     //
//                                                                           //
///////////////////////////////////////////////////////////////////////////////

#include "dxc/DXIL/DxilSemantic.h"
#include "dxc/DXIL/DxilShaderModel.h"
#include "dxc/DXIL/DxilSigPoint.h"
#include "dxc/DXIL/DxilSignature.h"
#include "dxc/Support/Global.h"

#include <string>

using std::string;

namespace hlsl {

//------------------------------------------------------------------------------
//
// Semantic class methods.
//
Semantic::Semantic(Kind Kind, const char *pszName)
    : m_Kind(Kind), m_pszName(pszName) {}

const Semantic *Semantic::GetByName(llvm::StringRef name) {
  if (!HasSVPrefix(name))
    return GetArbitrary();

  // The search is a simple linear scan as it is fairly infrequent operation and
  // the list is short. The search can be improved if linear traversal has
  // inadequate performance.
  for (unsigned i = (unsigned)Kind::Arbitrary + 1; i < (unsigned)Kind::Invalid;
       i++) {
    if (name.compare_lower(ms_SemanticTable[i].m_pszName) == 0)
      return &ms_SemanticTable[i];
  }

  return GetInvalid();
}

const Semantic *Semantic::GetByName(llvm::StringRef Name,
                                    DXIL::SigPointKind sigPointKind,
                                    unsigned MajorVersion,
                                    unsigned MinorVersion) {
  return Get(GetByName(Name)->GetKind(), sigPointKind, MajorVersion,
             MinorVersion);
}

const Semantic *Semantic::Get(Kind kind) {
  if (kind < Kind::Invalid)
    return &Semantic::ms_SemanticTable[(unsigned)kind];
  return GetInvalid();
}

const Semantic *Semantic::Get(Kind kind, DXIL::SigPointKind sigPointKind,
                              unsigned MajorVersion, unsigned MinorVersion) {
  if (sigPointKind == DXIL::SigPointKind::Invalid)
    return GetInvalid();
  const Semantic *pSemantic = Get(kind);
  DXIL::SemanticInterpretationKind SI = SigPoint::GetInterpretation(
      pSemantic->GetKind(), sigPointKind, MajorVersion, MinorVersion);
  if (SI == DXIL::SemanticInterpretationKind::NA)
    return GetInvalid();
  if (SI == DXIL::SemanticInterpretationKind::Arb)
    return GetArbitrary();
  return pSemantic;
}

const Semantic *Semantic::GetInvalid() {
  return &Semantic::ms_SemanticTable[(unsigned)Kind::Invalid];
}
const Semantic *Semantic::GetArbitrary() {
  return &Semantic::ms_SemanticTable[(unsigned)Kind::Arbitrary];
}

bool Semantic::HasSVPrefix(llvm::StringRef Name) {
  return Name.size() >= 3 && (Name[0] == 'S' || Name[0] == 's') &&
         (Name[1] == 'V' || Name[1] == 'v') && Name[2] == '_';
}

void Semantic::DecomposeNameAndIndex(llvm::StringRef FullName,
                                     llvm::StringRef *pName, unsigned *pIndex) {
  unsigned L = FullName.size(), i;

  for (i = L; i > 0; i--) {
    char d = FullName[i - 1];
    if ('0' > d || d > '9')
      break;
  }

  *pName = FullName.substr(0, i);

  if (i < L)
    *pIndex = atoi(FullName.data() + i);
  else
    *pIndex = 0;
}

Semantic::Kind Semantic::GetKind() const { return m_Kind; }

const char *Semantic::GetName() const { return m_pszName; }

bool Semantic::IsArbitrary() const { return GetKind() == Kind::Arbitrary; }

bool Semantic::IsInvalid() const { return m_Kind == Kind::Invalid; }

typedef Semantic SP;
const Semantic Semantic::ms_SemanticTable[kNumSemanticRecords] = {
    // Kind                         Name
    SP(Kind::Arbitrary, nullptr),
    SP(Kind::VertexID, "SV_VertexID"),
    SP(Kind::InstanceID, "SV_InstanceID"),
    SP(Kind::Position, "SV_Position"),
    SP(Kind::RenderTargetArrayIndex, "SV_RenderTargetArrayIndex"),
    SP(Kind::ViewPortArrayIndex, "SV_ViewportArrayIndex"),
    SP(Kind::ClipDistance, "SV_ClipDistance"),
    SP(Kind::CullDistance, "SV_CullDistance"),
    SP(Kind::OutputControlPointID, "SV_OutputControlPointID"),
    SP(Kind::DomainLocation, "SV_DomainLocation"),
    SP(Kind::PrimitiveID, "SV_PrimitiveID"),
    SP(Kind::GSInstanceID, "SV_GSInstanceID"),
    SP(Kind::SampleIndex, "SV_SampleIndex"),
    SP(Kind::IsFrontFace, "SV_IsFrontFace"),
    SP(Kind::Coverage, "SV_Coverage"),
    SP(Kind::InnerCoverage, "SV_InnerCoverage"),
    SP(Kind::Target, "SV_Target"),
    SP(Kind::Depth, "SV_Depth"),
    SP(Kind::DepthLessEqual, "SV_DepthLessEqual"),
    SP(Kind::DepthGreaterEqual, "SV_DepthGreaterEqual"),
    SP(Kind::StencilRef, "SV_StencilRef"),
    SP(Kind::DispatchThreadID, "SV_DispatchThreadID"),
    SP(Kind::GroupID, "SV_GroupID"),
    SP(Kind::GroupIndex, "SV_GroupIndex"),
    SP(Kind::GroupThreadID, "SV_GroupThreadID"),
    SP(Kind::TessFactor, "SV_TessFactor"),
    SP(Kind::InsideTessFactor, "SV_InsideTessFactor"),
    SP(Kind::ViewID, "SV_ViewID"),
    SP(Kind::Barycentrics, "SV_Barycentrics"),
    SP(Kind::ShadingRate, "SV_ShadingRate"),
    SP(Kind::CullPrimitive, "SV_CullPrimitive"),
    SP(Kind::StartVertexLocation, "SV_StartVertexLocation"),
    SP(Kind::StartInstanceLocation, "SV_StartInstanceLocation"),
    SP(Kind::Invalid, nullptr),
};

} // namespace hlsl