[clang] Fix __has_builtin

Fix __has_builtin to return 1 only if the requested target features
of a builtin are enabled by refactoring the code for checking
required target features of a builtin and use it in evaluation
of __has_builtin.

Reviewed by: Artem Belevich

Differential Revision: https://reviews.llvm.org/D125829

1 files changed, 12 insertions, 0 deletions

diff --git a/clang/lib/Basic/Builtins.cpp b/clang/lib/Basic/Builtins.cpp
index ef8bb56..b42e8f4 100644
--- a/clang/lib/Basic/Builtins.cpp
+++ b/clang/lib/Basic/Builtins.cpp
@@ -11,6 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/Basic/Builtins.h"
+#include "BuiltinTargetFeatures.h"
 #include "clang/Basic/IdentifierTable.h"
 #include "clang/Basic/LangOptions.h"
 #include "clang/Basic/TargetInfo.h"
@@ -211,3 +212,14 @@ bool Builtin::Context::canBeRedeclared(unsigned ID) const {
          (!hasReferenceArgsOrResult(ID) && !hasCustomTypechecking(ID)) ||
          isInStdNamespace(ID);
 }
+
+bool Builtin::evaluateRequiredTargetFeatures(
+    StringRef RequiredFeatures, const llvm::StringMap<bool> &TargetFetureMap) {
+  // Return true if the builtin doesn't have any required features.
+  if (RequiredFeatures.empty())
+    return true;
+  assert(!RequiredFeatures.contains(' ') && "Space in feature list");
+
+  TargetFeatures TF(TargetFetureMap);
+  return TF.hasRequiredFeatures(RequiredFeatures);
+}