From e40d4fdc8ad4a1257ccb2ef0b8a78e9b035f9d78 Mon Sep 17 00:00:00 2001
From: David Green <david.green@arm.com>
Date: Mon, 9 Sep 2019 10:46:25 +0000
Subject: [PATCH] [ARM] Prevent generating NEON stack accesses under MVE.

We should not be generating Neon stack loads/stores even for these large
registers.

No test here because my understanding is we will only generate these QQPR regs
for intrinsics and VLDn's. The tests will follow once those are available.

Differential revision: https://reviews.llvm.org/D67169


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371386 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/ARM/ARMBaseInstrInfo.cpp | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/lib/Target/ARM/ARMBaseInstrInfo.cpp b/lib/Target/ARM/ARMBaseInstrInfo.cpp
index 4a7f26d4fb2..270fefed380 100644
--- a/lib/Target/ARM/ARMBaseInstrInfo.cpp
+++ b/lib/Target/ARM/ARMBaseInstrInfo.cpp
@@ -1133,7 +1133,8 @@ storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
     case 24:
       if (ARM::DTripleRegClass.hasSubClassEq(RC)) {
         // Use aligned spills if the stack can be realigned.
-        if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
+        if (Align >= 16 && getRegisterInfo().canRealignStack(MF) &&
+            Subtarget.hasNEON()) {
           BuildMI(MBB, I, DebugLoc(), get(ARM::VST1d64TPseudo))
               .addFrameIndex(FI)
               .addImm(16)
@@ -1155,7 +1156,8 @@ storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
       break;
     case 32:
       if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) {
-        if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
+        if (Align >= 16 && getRegisterInfo().canRealignStack(MF) &&
+            Subtarget.hasNEON()) {
           // FIXME: It's possible to only store part of the QQ register if the
           // spilled def has a sub-register index.
           BuildMI(MBB, I, DebugLoc(), get(ARM::VST1d64QPseudo))
@@ -1368,7 +1370,8 @@ loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
     break;
   case 24:
     if (ARM::DTripleRegClass.hasSubClassEq(RC)) {
-      if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
+      if (Align >= 16 && getRegisterInfo().canRealignStack(MF) &&
+          Subtarget.hasNEON()) {
         BuildMI(MBB, I, DL, get(ARM::VLD1d64TPseudo), DestReg)
             .addFrameIndex(FI)
             .addImm(16)
@@ -1390,7 +1393,8 @@ loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
     break;
    case 32:
     if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) {
-      if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
+      if (Align >= 16 && getRegisterInfo().canRealignStack(MF) &&
+          Subtarget.hasNEON()) {
         BuildMI(MBB, I, DL, get(ARM::VLD1d64QPseudo), DestReg)
             .addFrameIndex(FI)
             .addImm(16)
-- 
2.50.1