1 files changed, 11 insertions, 0 deletions
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 128faffd7cd..0c75fd78dd7 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -4743,6 +4743,9 @@ bool X86TargetLowering::isMaskAndCmp0FoldingBeneficial(
 }
 
 bool X86TargetLowering::hasAndNotCompare(SDValue Y) const {
+  // A mask and compare against constant is ok for an 'andn' too
+  // even though the BMI instruction doesn't have an immediate form.
+
   if (!Subtarget.hasBMI())
     return false;
 
@@ -4754,6 +4757,14 @@ bool X86TargetLowering::hasAndNotCompare(SDValue Y) const {
   return true;
 }
 
+bool X86TargetLowering::hasAndNot(SDValue Y) const {
+  // x86 can't form 'andn' with an immediate.
+  if (isa<ConstantSDNode>(Y))
+    return false;
+
+  return hasAndNotCompare(Y);
+}
+
 MVT X86TargetLowering::hasFastEqualityCompare(unsigned NumBits) const {
   MVT VT = MVT::getIntegerVT(NumBits);
   if (isTypeLegal(VT))