Extract out a function onto CodeGenModule for getting the map of

features for a particular function, then use it to clean up some
code.

llvm-svn: 252819

clang/lib/CodeGen/CodeGenModule.cpp

@@ -3875,3 +3875,32 @@ llvm::MDTuple *CodeGenModule::CreateVTableBitSetEntry(
           llvm::ConstantInt::get(Int64Ty, Offset.getQuantity()))};
   return llvm::MDTuple::get(getLLVMContext(), BitsetOps);
 }
+
+// Fills in the supplied string map with the set of target features for the
+// passed in function.
+void CodeGenModule::getFunctionFeatureMap(llvm::StringMap<bool> &FeatureMap,
+                                          const FunctionDecl *FD) {
+  StringRef TargetCPU = Target.getTargetOpts().CPU;
+  if (const auto *TD = FD->getAttr<TargetAttr>()) {
+    // If we have a TargetAttr build up the feature map based on that.
+    TargetAttr::ParsedTargetAttr ParsedAttr = TD->parse();
+
+    // Make a copy of the features as passed on the command line into the
+    // beginning of the additional features from the function to override.
+    ParsedAttr.first.insert(ParsedAttr.first.begin(),
+                            Target.getTargetOpts().FeaturesAsWritten.begin(),
+                            Target.getTargetOpts().FeaturesAsWritten.end());
+
+    if (ParsedAttr.second != "")
+      TargetCPU = ParsedAttr.second;
+
+    // Now populate the feature map, first with the TargetCPU which is either
+    // the default or a new one from the target attribute string. Then we'll use
+    // the passed in features (FeaturesAsWritten) along with the new ones from
+    // the attribute.
+    Target.initFeatureMap(FeatureMap, getDiags(), TargetCPU, ParsedAttr.first);
+  } else {
+    Target.initFeatureMap(FeatureMap, getDiags(), TargetCPU,
+                          Target.getTargetOpts().Features);
+  }
+}