Add support for i1 compare operations to X86 FastISel, and ignore llvm.assume()

intrinsics in the target-independent FastISel.

Author: pcwalton

lib/CodeGen/SelectionDAG/FastISel.cpp

@@ -1100,6 +1100,8 @@ bool FastISel::selectIntrinsicCall(const IntrinsicInst *II) {
   // At -O0 we don't care about the lifetime intrinsics.
   case Intrinsic::lifetime_start:
   case Intrinsic::lifetime_end:
+  // At -O0 we don't care about assumptions.
+  case Intrinsic::assume:
   // The donothing intrinsic does, well, nothing.
   case Intrinsic::donothing:
     return true;

lib/Target/X86/X86FastISel.cpp

@@ -1164,6 +1164,7 @@ static unsigned X86ChooseCmpOpcode(EVT VT, const X86Subtarget *Subtarget) {
 
   switch (VT.getSimpleVT().SimpleTy) {
   default:       return 0;
+  case MVT::i1:  return X86::CMP8rr;
   case MVT::i8:  return X86::CMP8rr;
   case MVT::i16: return X86::CMP16rr;
   case MVT::i32: return X86::CMP32rr;