X86InstrInfo.td

def : Pat<(i16 (anyext R8 :$src)), (MOVZX16rr8  R8 :$src)>;
def : Pat<(i32 (anyext R8 :$src)), (MOVZX32rr8  R8 :$src)>;
def : Pat<(i32 (anyext R16:$src)), (MOVZX32rr16 R16:$src)>;

// Required for RET of f32 / f64 values.
def : Pat<(X86fld addr:$src, f32), (FpLD32m addr:$src)>;
def : Pat<(X86fld addr:$src, f64), (FpLD64m addr:$src)>;

// Required for CALL which return f32 / f64 values.
def : Pat<(X86fst RFP:$src, addr:$op, f32), (FpST32m addr:$op, RFP:$src)>;
def : Pat<(X86fst RFP:$src, addr:$op, f64), (FpST64m addr:$op, RFP:$src)>;

// Floatin point constant -0.0 and -1.0
def : Pat<(f64 fp64immneg0), (FpCHS (FpLD0))>, Requires<[FPStack]>;
def : Pat<(f64 fp64immneg1), (FpCHS (FpLD1))>, Requires<[FPStack]>;

// RFP undef
def : Pat<(f64 (undef)), (FpLD0)>,  Requires<[FPStack]>;


//===----------------------------------------------------------------------===//
// Some peepholes
//===----------------------------------------------------------------------===//

// (shl x, 1) ==> (add x, x)
def : Pat<(shl R8 :$src1, (i8 1)), (ADD8rr  R8 :$src1, R8 :$src1)>;
def : Pat<(shl R16:$src1, (i8 1)), (ADD16rr R16:$src1, R16:$src1)>;
def : Pat<(shl R32:$src1, (i8 1)), (ADD32rr R32:$src1, R32:$src1)>;