diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index ab14fd40126..159b01112c2 100644
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -229,8 +229,8 @@ def i32immSExt8  : PatLeaf<(i32 imm), [{
 }]>;
 
 // Helper fragments for loads.
-// It's always safe to treat a anyext i16 load as a i32 load. Ditto for
-// i8 to i16.
+// It's always safe to treat a anyext i16 load as a i32 load if the i16 is
+// known to be 32-bit aligned or better. Ditto for i8 to i16.
 def loadi16 : PatFrag<(ops node:$ptr), (i16 (ld node:$ptr)), [{
   if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
     if (LD->getAddressingMode() != ISD::UNINDEXED)
@@ -239,7 +239,7 @@ def loadi16 : PatFrag<(ops node:$ptr), (i16 (ld node:$ptr)), [{
     if (ExtType == ISD::NON_EXTLOAD)
       return true;
     if (ExtType == ISD::EXTLOAD)
-      return LD->getAlignment() >= 8 && !LD->isVolatile();
+      return LD->getAlignment() >= 16 && !LD->isVolatile();
   }
   return false;
 }]>;
@@ -252,7 +252,7 @@ def loadi32 : PatFrag<(ops node:$ptr), (i32 (ld node:$ptr)), [{
     if (ExtType == ISD::NON_EXTLOAD)
       return true;
     if (ExtType == ISD::EXTLOAD)
-      return LD->getAlignment() >= 16 && !LD->isVolatile();
+      return LD->getAlignment() >= 32 && !LD->isVolatile();
   }
   return false;
 }]>;