2 files changed, 19 insertions, 0 deletions
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index f0d8f222104..ede29662e14 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -58,6 +58,12 @@ using namespace llvm;
 
 STATISTIC(NumTailCalls, "Number of tail calls");
 
+static cl::opt<bool> ExperimentalVectorWideningLegalization(
+    "x86-experimental-vector-widening-legalization", cl::init(false),
+    cl::desc("Enable an experimental vector type legalization through widening "
+             "rather than promotion."),
+    cl::Hidden);
+
 static cl::opt<bool> ExperimentalVectorShuffleLowering(
     "x86-experimental-vector-shuffle-lowering", cl::init(false),
     cl::desc("Enable an experimental vector shuffle lowering code path."),
@@ -1588,6 +1594,16 @@ void X86TargetLowering::resetOperationActions() {
   setPrefFunctionAlignment(4); // 2^4 bytes.
 }
 
+TargetLoweringBase::LegalizeTypeAction
+X86TargetLowering::getPreferredVectorAction(EVT VT) const {
+  if (ExperimentalVectorWideningLegalization &&
+      VT.getVectorNumElements() != 1 &&
+      VT.getVectorElementType().getSimpleVT() != MVT::i1)
+    return TypeWidenVector;
+
+  return TargetLoweringBase::getPreferredVectorAction(VT);
+}
+
 EVT X86TargetLowering::getSetCCResultType(LLVMContext &, EVT VT) const {
   if (!VT.isVector())
     return Subtarget->hasAVX512() ? MVT::i1: MVT::i8;
diff --git a/llvm/lib/Target/X86/X86ISelLowering.h b/llvm/lib/Target/X86/X86ISelLowering.h
index 10754825a6d..c8cdce7c766 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.h
+++ b/llvm/lib/Target/X86/X86ISelLowering.h
@@ -796,6 +796,9 @@ namespace llvm {
     /// \brief Reset the operation actions based on target options.
     void resetOperationActions() override;
 
+    /// \brief Customize the preferred legalization strategy for certain types.
+    LegalizeTypeAction getPreferredVectorAction(EVT VT) const override;
+
   protected:
     std::pair<const TargetRegisterClass*, uint8_t>
     findRepresentativeClass(MVT VT) const override;