1 files changed, 8 insertions, 1 deletions
diff --git a/llvm/lib/Target/X86/X86FastISel.cpp b/llvm/lib/Target/X86/X86FastISel.cpp
index a8260c2161f..c10393f0ca7 100644
--- a/llvm/lib/Target/X86/X86FastISel.cpp
+++ b/llvm/lib/Target/X86/X86FastISel.cpp
@@ -1097,6 +1097,7 @@ static unsigned X86ChooseCmpOpcode(EVT VT, const X86Subtarget *Subtarget) {
 /// If we have a comparison with RHS as the RHS  of the comparison, return an
 /// opcode that works for the compare (e.g. CMP32ri) otherwise return 0.
 static unsigned X86ChooseCmpImmediateOpcode(EVT VT, const ConstantInt *RHSC) {
+  int64_t Val = RHSC->getSExtValue();
   switch (VT.getSimpleVT().SimpleTy) {
   // Otherwise, we can't fold the immediate into this comparison.
   default:
@@ -1104,13 +1105,19 @@ static unsigned X86ChooseCmpImmediateOpcode(EVT VT, const ConstantInt *RHSC) {
   case MVT::i8:
     return X86::CMP8ri;
   case MVT::i16:
+    if (isInt<8>(Val))
+      return X86::CMP16ri8;
     return X86::CMP16ri;
   case MVT::i32:
+    if (isInt<8>(Val))
+      return X86::CMP32ri8;
     return X86::CMP32ri;
   case MVT::i64:
+    if (isInt<8>(Val))
+      return X86::CMP64ri8;
     // 64-bit comparisons are only valid if the immediate fits in a 32-bit sext
     // field.
-    if ((int)RHSC->getSExtValue() == RHSC->getSExtValue())
+    if (isInt<32>(Val))
       return X86::CMP64ri32;
     return 0;
   }