[ARM] Mark VMOV with immediate: isAsCheapAsMove.

[oota-llvm.git] / lib / Target / ARM / ARMInstrNEON.td

diff --git a/lib/Target/ARM/ARMInstrNEON.td b/lib/Target/ARM/ARMInstrNEON.td
index 7020ffb41b643e8c25e7c69de6a9b7f75d587e72..defef4ea907345c55635b09becf00083d1ed3e54 100644 (file)
--- a/lib/Target/ARM/ARMInstrNEON.td
+++ b/lib/Target/ARM/ARMInstrNEON.td
@@ -5689,7 +5689,10 @@ def : NEONInstAlias<"vmov${p} $Vd, $Vm",
 
 //   VMOV     : Vector Move (Immediate)
 
-let isReMaterializable = 1 in {
+// Although VMOVs are not strictly speaking cheap, they are as expensive
+// as their copies counterpart (VORR), so we should prefer rematerialization
+// over splitting when it applies.
+let isReMaterializable = 1, isAsCheapAsAMove=1 in {
 def VMOVv8i8  : N1ModImm<1, 0b000, 0b1110, 0, 0, 0, 1, (outs DPR:$Vd),
                          (ins nImmSplatI8:$SIMM), IIC_VMOVImm,
                          "vmov", "i8", "$Vd, $SIMM", "",
@@ -5744,7 +5747,7 @@ def VMOVv4f32 : N1ModImm<1, 0b000, 0b1111, 0, 1, 0, 1, (outs QPR:$Vd),
                          (ins nImmVMOVF32:$SIMM), IIC_VMOVImm,
                          "vmov", "f32", "$Vd, $SIMM", "",
                          [(set QPR:$Vd, (v4f32 (NEONvmovFPImm timm:$SIMM)))]>;
-} // isReMaterializable
+} // isReMaterializable, isAsCheapAsAMove
 
 // Add support for bytes replication feature, so it could be GAS compatible.
 // E.g. instructions below: