Revert "[Clang][LoongArch] Support target attribute for function" (#141998)

Reverts #140700

This breaks bots both in buildbot and downstream CI: 
- https://lab.llvm.org/buildbot/#/builders/11/builds/16173
- https://lab.llvm.org/buildbot/#/builders/202/builds/1531
-
https://ci.chromium.org/ui/p/fuchsia/builders/toolchain.ci/clang-host-linux-x64/b8713537585914796017/overview

Author: ilovepi

clang/lib/Basic/Targets/LoongArch.cpp

@@ -393,73 +393,6 @@ bool LoongArchTargetInfo::handleTargetFeatures(
   return true;
 }
 
-enum class AttrFeatureKind { Arch, Tune, NoFeature, Feature };
-
-static std::pair<AttrFeatureKind, llvm::StringRef>
-getAttrFeatureTypeAndValue(llvm::StringRef AttrFeature) {
-  if (auto Split = AttrFeature.split("="); !Split.second.empty()) {
-    if (Split.first.trim() == "arch")
-      return {AttrFeatureKind::Arch, Split.second.trim()};
-    if (Split.first.trim() == "tune")
-      return {AttrFeatureKind::Tune, Split.second.trim()};
-  }
-  if (AttrFeature.starts_with("no-"))
-    return {AttrFeatureKind::NoFeature, AttrFeature.drop_front(3)};
-  return {AttrFeatureKind::Feature, AttrFeature};
-}
-
-ParsedTargetAttr
-LoongArchTargetInfo::parseTargetAttr(StringRef Features) const {
-  ParsedTargetAttr Ret;
-  if (Features == "default")
-    return Ret;
-  SmallVector<StringRef, 1> AttrFeatures;
-  Features.split(AttrFeatures, ",");
-
-  for (auto &Feature : AttrFeatures) {
-    auto [Kind, Value] = getAttrFeatureTypeAndValue(Feature.trim());
-
-    switch (Kind) {
-    case AttrFeatureKind::Arch: {
-      if (llvm::LoongArch::isValidArchName(Value) || Value == "la64v1.0" ||
-          Value == "la64v1.1") {
-        std::vector<llvm::StringRef> ArchFeatures;
-        if (llvm::LoongArch::getArchFeatures(Value, ArchFeatures)) {
-          Ret.Features.insert(Ret.Features.end(), ArchFeatures.begin(),
-                              ArchFeatures.end());
-        }
-
-        if (!Ret.CPU.empty())
-          Ret.Duplicate = "arch=";
-        else if (Value == "la64v1.0" || Value == "la64v1.1")
-          Ret.CPU = "loongarch64";
-        else
-          Ret.CPU = Value;
-      } else {
-        Ret.Features.push_back("!arch=" + Value.str());
-      }
-      break;
-    }
-
-    case AttrFeatureKind::Tune:
-      if (!Ret.Tune.empty())
-        Ret.Duplicate = "tune=";
-      else
-        Ret.Tune = Value;
-      break;
-
-    case AttrFeatureKind::NoFeature:
-      Ret.Features.push_back("-" + Value.str());
-      break;
-
-    case AttrFeatureKind::Feature:
-      Ret.Features.push_back("+" + Value.str());
-      break;
-    }
-  }
-  return Ret;
-}
-
 bool LoongArchTargetInfo::isValidCPUName(StringRef Name) const {
   return llvm::LoongArch::isValidCPUName(Name);
 }
@@ -468,7 +401,3 @@ void LoongArchTargetInfo::fillValidCPUList(
     SmallVectorImpl<StringRef> &Values) const {
   llvm::LoongArch::fillValidCPUList(Values);
 }
-
-bool LoongArchTargetInfo::isValidFeatureName(StringRef Name) const {
-  return llvm::LoongArch::isValidFeatureName(Name);
-}

clang/lib/Basic/Targets/LoongArch.h

@@ -101,9 +101,6 @@ class LLVM_LIBRARY_VISIBILITY LoongArchTargetInfo : public TargetInfo {
   bool handleTargetFeatures(std::vector<std::string> &Features,
                             DiagnosticsEngine &Diags) override;
 
-  ParsedTargetAttr parseTargetAttr(StringRef Str) const override;
-  bool supportsTargetAttributeTune() const override { return true; }
-
   bool
   initFeatureMap(llvm::StringMap<bool> &Features, DiagnosticsEngine &Diags,
                  StringRef CPU,
@@ -113,7 +110,6 @@ class LLVM_LIBRARY_VISIBILITY LoongArchTargetInfo : public TargetInfo {
 
   bool isValidCPUName(StringRef Name) const override;
   void fillValidCPUList(SmallVectorImpl<StringRef> &Values) const override;
-  bool isValidFeatureName(StringRef Name) const override;
 };
 
 class LLVM_LIBRARY_VISIBILITY LoongArch32TargetInfo

clang/lib/Sema/SemaDeclAttr.cpp

@@ -3195,17 +3195,6 @@ bool Sema::checkTargetAttr(SourceLocation LiteralLoc, StringRef AttrStr) {
     }
   }
 
-  if (Context.getTargetInfo().getTriple().isLoongArch()) {
-    for (const auto &Feature : ParsedAttrs.Features) {
-      StringRef CurFeature = Feature;
-      if (CurFeature.starts_with("!arch=")) {
-        StringRef ArchValue = CurFeature.split("=").second.trim();
-        return Diag(LiteralLoc, diag::err_attribute_unsupported)
-               << "target(arch=..)" << ArchValue;
-      }
-    }
-  }
-
   if (ParsedAttrs.Duplicate != "")
     return Diag(LiteralLoc, diag::warn_unsupported_target_attribute)
            << Duplicate << None << ParsedAttrs.Duplicate << Target;

clang/test/CodeGen/LoongArch/targetattr.c

@@ -85,7 +85,6 @@ struct ArchInfo {
 };
 
 bool isValidArchName(StringRef Arch);
-bool isValidFeatureName(StringRef Feature);
 bool getArchFeatures(StringRef Arch, std::vector<StringRef> &Features);
 bool isValidCPUName(StringRef TuneCPU);
 void fillValidCPUList(SmallVectorImpl<StringRef> &Values);

clang/test/Sema/attr-target-loongarch.c

@@ -34,18 +34,6 @@ bool LoongArch::isValidArchName(StringRef Arch) {
   return false;
 }
 
-bool LoongArch::isValidFeatureName(StringRef Feature) {
-  if (Feature.starts_with("+") || Feature.starts_with("-"))
-    return false;
-  for (const auto &F : AllFeatures) {
-    StringRef CanonicalName =
-        F.Name.starts_with("+") ? F.Name.drop_front() : F.Name;
-    if (CanonicalName == Feature)
-      return true;
-  }
-  return false;
-}
-
 bool LoongArch::getArchFeatures(StringRef Arch,
                                 std::vector<StringRef> &Features) {
   for (const auto A : AllArchs) {