Add X86 LZCNT instruction. Including instruction selection support.

[oota-llvm.git] / lib / Target / X86 / X86ISelLowering.cpp

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 5bd3e2b6711bb06178fb45fc2019f546f21dfd5a..251064b3bb0dc7e87db45441bba1891abaf1fe4d 100644 (file)
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -380,14 +380,19 @@ X86TargetLowering::X86TargetLowering(X86TargetMachine &TM)
   setOperationAction(ISD::FLT_ROUNDS_      , MVT::i32  , Custom);
 
   setOperationAction(ISD::CTTZ             , MVT::i8   , Custom);
-  setOperationAction(ISD::CTLZ             , MVT::i8   , Custom);
   setOperationAction(ISD::CTTZ             , MVT::i16  , Custom);
-  setOperationAction(ISD::CTLZ             , MVT::i16  , Custom);
   setOperationAction(ISD::CTTZ             , MVT::i32  , Custom);
-  setOperationAction(ISD::CTLZ             , MVT::i32  , Custom);
-  if (Subtarget->is64Bit()) {
+  if (Subtarget->is64Bit())
     setOperationAction(ISD::CTTZ           , MVT::i64  , Custom);
-    setOperationAction(ISD::CTLZ           , MVT::i64  , Custom);
+
+  if (Subtarget->hasLZCNT()) {
+    setOperationAction(ISD::CTLZ           , MVT::i8   , Promote);
+  } else {
+    setOperationAction(ISD::CTLZ           , MVT::i8   , Custom);
+    setOperationAction(ISD::CTLZ           , MVT::i16  , Custom);
+    setOperationAction(ISD::CTLZ           , MVT::i32  , Custom);
+    if (Subtarget->is64Bit())
+      setOperationAction(ISD::CTLZ         , MVT::i64  , Custom);
   }
 
   if (Subtarget->hasPOPCNT()) {