Make LLVMRustHasFeature more robust

The function should accept feature strings that old LLVM might not
support.

Simplify the code using the same approach used by
LLVMRustPrintTargetFeatures.

Dummify the function for non 4.0 LLVM and update the tests accordingly.

1 files changed, 7 insertions, 13 deletions

diff --git a/src/rustllvm/PassWrapper.cpp b/src/rustllvm/PassWrapper.cpp
index 7fb1eafb30d..57e90be2774 100644
--- a/src/rustllvm/PassWrapper.cpp
+++ b/src/rustllvm/PassWrapper.cpp
@@ -181,20 +181,14 @@ extern "C" bool LLVMRustHasFeature(LLVMTargetMachineRef TM,
   TargetMachine *Target = unwrap(TM);
   const MCSubtargetInfo *MCInfo = Target->getMCSubtargetInfo();
   const FeatureBitset &Bits = MCInfo->getFeatureBits();
-  const llvm::SubtargetFeatureKV *FeatureEntry;
-
-#define SUBTARGET(x)                                                           \
-  if (MCInfo->isCPUStringValid(x##SubTypeKV[0].Key)) {                         \
-    FeatureEntry = x##FeatureKV;                                               \
-  } else
-
-  GEN_SUBTARGETS { return false; }
-#undef SUBTARGET
-
-  while (strcmp(Feature, FeatureEntry->Key) != 0)
-    FeatureEntry++;
+#if LLVM_VERSION_GE(4, 0)
+  const ArrayRef<SubtargetFeatureKV> FeatTable = MCInfo->getFeatureTable();
 
-  return (Bits & FeatureEntry->Value) == FeatureEntry->Value;
+  for (auto &FeatureEntry : FeatTable)
+    if (!strcmp(FeatureEntry.Key, Feature))
+      return (Bits & FeatureEntry.Value) == FeatureEntry.Value;
+#endif
+  return false;
 }
 
 enum class LLVMRustCodeModel {