[Thumb-1] Add optimized constant materialization for integers [256..512)
We can materialize these integers using a MOV; ADDi8 pair.
llvm-svn: 272007
diff --git a/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp b/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
index 0aacd67..cc835df 100644
--- a/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
+++ b/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
@@ -485,6 +485,7 @@
if (Subtarget->isThumb()) {
if (Val <= 255) return 1; // MOV
if (Subtarget->hasV6T2Ops() && Val <= 0xffff) return 1; // MOVW
+ if (Val <= 511) return 2; // MOV + ADDi8
if (~Val <= 255) return 2; // MOV + MVN
if (ARM_AM::isThumbImmShiftedVal(Val)) return 2; // MOV + LSL
} else {