Add support for moving pure S-register to NEON pipeline if desired
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162898 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMBaseInstrInfo.cpp b/lib/Target/ARM/ARMBaseInstrInfo.cpp
index 41d0c57..7b7b6e3 100644
--- a/lib/Target/ARM/ARMBaseInstrInfo.cpp
+++ b/lib/Target/ARM/ARMBaseInstrInfo.cpp
@@ -3377,7 +3377,8 @@
// converted.
if (Subtarget.isCortexA9() && !isPredicated(MI) &&
(MI->getOpcode() == ARM::VMOVRS ||
- MI->getOpcode() == ARM::VMOVSR))
+ MI->getOpcode() == ARM::VMOVSR ||
+ MI->getOpcode() == ARM::VMOVS))
return std::make_pair(ExeVFP, (1<<ExeVFP) | (1<<ExeNEON));
// No other instructions can be swizzled, so just determine their domain.
@@ -3490,10 +3491,78 @@
.addReg(DReg, RegState::Undef)
.addReg(SrcReg)
.addImm(Lane));
-
+
// The destination must be marked as set.
MIB.addReg(DstReg, RegState::Define | RegState::Implicit);
break;
+ case ARM::VMOVS: {
+ if (Domain != ExeNEON)
+ break;
+
+ // Source instruction is %SDst = VMOVS %SSrc, 14, %noreg (; implicits)
+ DstReg = MI->getOperand(0).getReg();
+ SrcReg = MI->getOperand(1).getReg();
+
+ for (unsigned i = MI->getDesc().getNumOperands(); i; --i)
+ MI->RemoveOperand(i-1);
+
+ unsigned DstLane = 0, SrcLane = 0, DDst, DSrc;
+ DDst = getCorrespondingDRegAndLane(TRI, DstReg, DstLane);
+ DSrc = getCorrespondingDRegAndLane(TRI, SrcReg, SrcLane);
+
+ if (DSrc == DDst) {
+ // Destination can be:
+ // %DDst = VDUPLN32d %DDst, Lane, 14, %noreg (; implicits)
+ MI->setDesc(get(ARM::VDUPLN32d));
+ AddDefaultPred(MIB.addReg(DDst, RegState::Define)
+ .addReg(DDst, RegState::Undef)
+ .addImm(SrcLane));
+
+ // Neither the source or the destination are naturally represented any
+ // more, so add them in manually.
+ MIB.addReg(DstReg, RegState::Implicit | RegState::Define);
+ MIB.addReg(SrcReg, RegState::Implicit);
+ break;
+ }
+
+ // In general there's no single instruction that can perform an S <-> S
+ // move in NEON space, but a pair of VEXT instructions *can* do the
+ // job. It turns out that the VEXTs needed will only use DSrc once, with
+ // the position based purely on the combination of lane-0 and lane-1
+ // involved. For example
+ // vmov s0, s2 -> vext.32 d0, d0, d1, #1 vext.32 d0, d0, d0, #1
+ // vmov s1, s3 -> vext.32 d0, d1, d0, #1 vext.32 d0, d0, d0, #1
+ // vmov s0, s3 -> vext.32 d0, d0, d0, #1 vext.32 d0, d1, d0, #1
+ // vmov s1, s2 -> vext.32 d0, d0, d0, #1 vext.32 d0, d0, d1, #1
+ //
+ // Pattern of the MachineInstrs is:
+ // %DDst = VEXTd32 %DSrc1, %DSrc2, Lane, 14, %noreg (;implicits)
+ MachineInstrBuilder NewMIB;
+ NewMIB = BuildMI(*MI->getParent(), MI, MI->getDebugLoc(),
+ get(ARM::VEXTd32), DDst);
+ NewMIB.addReg(SrcLane == 1 && DstLane == 1 ? DSrc : DDst, RegState::Undef);
+ NewMIB.addReg(SrcLane == 0 && DstLane == 0 ? DSrc : DDst, RegState::Undef);
+ NewMIB.addImm(1);
+ AddDefaultPred(NewMIB);
+
+ if (SrcLane == DstLane)
+ NewMIB.addReg(SrcReg, RegState::Implicit);
+
+ MI->setDesc(get(ARM::VEXTd32));
+ MIB.addReg(DDst, RegState::Define);
+ MIB.addReg(SrcLane == 1 && DstLane == 0 ? DSrc : DDst, RegState::Undef);
+ MIB.addReg(SrcLane == 0 && DstLane == 1 ? DSrc : DDst, RegState::Undef);
+ MIB.addImm(1);
+ AddDefaultPred(MIB);
+
+ if (SrcLane != DstLane)
+ MIB.addReg(SrcReg, RegState::Implicit);
+
+ // As before, the original destination is no longer represented, add it
+ // implicitly.
+ MIB.addReg(DstReg, RegState::Define | RegState::Implicit);
+ break;
+ }
}
}