1 files changed, 32 insertions, 10 deletions

diff --git a/clang/lib/Basic/TargetID.cpp b/clang/lib/Basic/TargetID.cpp
index abfbe49e1a91..7cc4d67e3a52 100644
--- a/clang/lib/Basic/TargetID.cpp
+++ b/clang/lib/Basic/TargetID.cpp
@@ -12,6 +12,7 @@
 #include "llvm/Support/TargetParser.h"
 #include "llvm/Support/raw_ostream.h"
 #include <map>
+#include <optional>
 
 namespace clang {
 
@@ -62,7 +63,7 @@ llvm::StringRef getProcessorFromTargetID(const llvm::Triple &T,
 // A target ID is a processor name followed by a list of target features
 // delimited by colon. Each target feature is a string post-fixed by a plus
 // or minus sign, e.g. gfx908:sramecc+:xnack-.
-static llvm::Optional<llvm::StringRef>
+static std::optional<llvm::StringRef>
 parseTargetIDWithFormatCheckingOnly(llvm::StringRef TargetID,
                                     llvm::StringMap<bool> *FeatureMap) {
   llvm::StringRef Processor;
@@ -73,7 +74,7 @@ parseTargetIDWithFormatCheckingOnly(llvm::StringRef TargetID,
   auto Split = TargetID.split(':');
   Processor = Split.first;
   if (Processor.empty())
-    return llvm::None;
+    return std::nullopt;
 
   auto Features = Split.second;
   if (Features.empty())
@@ -88,30 +89,30 @@ parseTargetIDWithFormatCheckingOnly(llvm::StringRef TargetID,
     auto Sign = Splits.first.back();
     auto Feature = Splits.first.drop_back();
     if (Sign != '+' && Sign != '-')
-      return llvm::None;
+      return std::nullopt;
     bool IsOn = Sign == '+';
     auto Loc = FeatureMap->find(Feature);
     // Each feature can only show up at most once in target ID.
     if (Loc != FeatureMap->end())
-      return llvm::None;
+      return std::nullopt;
     (*FeatureMap)[Feature] = IsOn;
     Features = Splits.second;
   }
   return Processor;
 }
 
-llvm::Optional<llvm::StringRef>
+std::optional<llvm::StringRef>
 parseTargetID(const llvm::Triple &T, llvm::StringRef TargetID,
               llvm::StringMap<bool> *FeatureMap) {
   auto OptionalProcessor =
       parseTargetIDWithFormatCheckingOnly(TargetID, FeatureMap);
 
   if (!OptionalProcessor)
-    return llvm::None;
+    return std::nullopt;
 
   llvm::StringRef Processor = getCanonicalProcessorName(T, *OptionalProcessor);
   if (Processor.empty())
-    return llvm::None;
+    return std::nullopt;
 
   llvm::SmallSet<llvm::StringRef, 4> AllFeatures;
   for (auto &&F : getAllPossibleTargetIDFeatures(T, Processor))
@@ -119,7 +120,7 @@ parseTargetID(const llvm::Triple &T, llvm::StringRef TargetID,
 
   for (auto &&F : *FeatureMap)
     if (!AllFeatures.count(F.first()))
-      return llvm::None;
+      return std::nullopt;
 
   return Processor;
 }
@@ -140,7 +141,7 @@ std::string getCanonicalTargetID(llvm::StringRef Processor,
 // For a specific processor, a feature either shows up in all target IDs, or
 // does not show up in any target IDs. Otherwise the target ID combination
 // is invalid.
-llvm::Optional<std::pair<llvm::StringRef, llvm::StringRef>>
+std::optional<std::pair<llvm::StringRef, llvm::StringRef>>
 getConflictTargetIDCombination(const std::set<llvm::StringRef> &TargetIDs) {
   struct Info {
     llvm::StringRef TargetID;
@@ -161,7 +162,28 @@ getConflictTargetIDCombination(const std::set<llvm::StringRef> &TargetIDs) {
         return std::make_pair(Loc->second.TargetID, ID);
     }
   }
-  return llvm::None;
+  return std::nullopt;
+}
+
+bool isCompatibleTargetID(llvm::StringRef Provided, llvm::StringRef Requested) {
+  llvm::StringMap<bool> ProvidedFeatures, RequestedFeatures;
+  llvm::StringRef ProvidedProc =
+      *parseTargetIDWithFormatCheckingOnly(Provided, &ProvidedFeatures);
+  llvm::StringRef RequestedProc =
+      *parseTargetIDWithFormatCheckingOnly(Requested, &RequestedFeatures);
+  if (ProvidedProc != RequestedProc)
+    return false;
+  for (const auto &F : ProvidedFeatures) {
+    auto Loc = RequestedFeatures.find(F.first());
+    // The default (unspecified) value of a feature is 'All', which can match
+    // either 'On' or 'Off'.
+    if (Loc == RequestedFeatures.end())
+      return false;
+    // If a feature is specified, it must have exact match.
+    if (Loc->second != F.second)
+      return false;
+  }
+  return true;
 }
 
 } // namespace clang