From ccca22e9e2e03bdd782b1d4bf880ebf79e7b7e77 Mon Sep 17 00:00:00 2001 From: Jakob Stoklund Olesen Date: Thu, 29 Mar 2012 22:54:32 +0000 Subject: Prefer even-odd D-register pairs. We are sometimes allocatinog from the DPair register class which contains odd-even pairs in addition to the Q registers. Place the Q registers first in the DPair allocation order as they can be copied with a single instruction. The odd-even pairs should only be allocated as a last resort. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153699 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/ARM/ARMRegisterInfo.td | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/lib/Target/ARM/ARMRegisterInfo.td b/lib/Target/ARM/ARMRegisterInfo.td index 1327fb840e..1466e983f3 100644 --- a/lib/Target/ARM/ARMRegisterInfo.td +++ b/lib/Target/ARM/ARMRegisterInfo.td @@ -314,7 +314,8 @@ def TuplesOE2D : RegisterTuples<[dsub_0, dsub_1], def DPair : RegisterClass<"ARM", [v16i8, v8i16, v4i32, v2i64, v4f32, v2f64], 128, (interleave QPR, TuplesOE2D)> { // Allocate starting at non-VFP2 registers D16-D31 first. - let AltOrders = [(rotl DPair, 16)]; + // Prefer even-odd pairs as they are easier to copy. + let AltOrders = [(add (rotl QPR, 8), (rotl DPair, 16))]; let AltOrderSelect = [{ return 1; }]; } -- cgit v1.2.3