summaryrefslogtreecommitdiffstats
path: root/lib/Target/ARM/NEONPreAllocPass.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'lib/Target/ARM/NEONPreAllocPass.cpp')
-rw-r--r--lib/Target/ARM/NEONPreAllocPass.cpp394
1 files changed, 394 insertions, 0 deletions
diff --git a/lib/Target/ARM/NEONPreAllocPass.cpp b/lib/Target/ARM/NEONPreAllocPass.cpp
new file mode 100644
index 0000000..821b872
--- /dev/null
+++ b/lib/Target/ARM/NEONPreAllocPass.cpp
@@ -0,0 +1,394 @@
+//===-- NEONPreAllocPass.cpp - Allocate adjacent NEON registers--*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "neon-prealloc"
+#include "ARM.h"
+#include "ARMInstrInfo.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+using namespace llvm;
+
+namespace {
+ class VISIBILITY_HIDDEN NEONPreAllocPass : public MachineFunctionPass {
+ const TargetInstrInfo *TII;
+
+ public:
+ static char ID;
+ NEONPreAllocPass() : MachineFunctionPass(&ID) {}
+
+ virtual bool runOnMachineFunction(MachineFunction &MF);
+
+ virtual const char *getPassName() const {
+ return "NEON register pre-allocation pass";
+ }
+
+ private:
+ bool PreAllocNEONRegisters(MachineBasicBlock &MBB);
+ };
+
+ char NEONPreAllocPass::ID = 0;
+}
+
+static bool isNEONMultiRegOp(int Opcode, unsigned &FirstOpnd, unsigned &NumRegs,
+ unsigned &Offset, unsigned &Stride) {
+ // Default to unit stride with no offset.
+ Stride = 1;
+ Offset = 0;
+
+ switch (Opcode) {
+ default:
+ break;
+
+ case ARM::VLD2d8:
+ case ARM::VLD2d16:
+ case ARM::VLD2d32:
+ case ARM::VLD2d64:
+ case ARM::VLD2LNd8:
+ case ARM::VLD2LNd16:
+ case ARM::VLD2LNd32:
+ FirstOpnd = 0;
+ NumRegs = 2;
+ return true;
+
+ case ARM::VLD2q8:
+ case ARM::VLD2q16:
+ case ARM::VLD2q32:
+ FirstOpnd = 0;
+ NumRegs = 4;
+ return true;
+
+ case ARM::VLD2LNq16a:
+ case ARM::VLD2LNq32a:
+ FirstOpnd = 0;
+ NumRegs = 2;
+ Offset = 0;
+ Stride = 2;
+ return true;
+
+ case ARM::VLD2LNq16b:
+ case ARM::VLD2LNq32b:
+ FirstOpnd = 0;
+ NumRegs = 2;
+ Offset = 1;
+ Stride = 2;
+ return true;
+
+ case ARM::VLD3d8:
+ case ARM::VLD3d16:
+ case ARM::VLD3d32:
+ case ARM::VLD3d64:
+ case ARM::VLD3LNd8:
+ case ARM::VLD3LNd16:
+ case ARM::VLD3LNd32:
+ FirstOpnd = 0;
+ NumRegs = 3;
+ return true;
+
+ case ARM::VLD3q8a:
+ case ARM::VLD3q16a:
+ case ARM::VLD3q32a:
+ FirstOpnd = 0;
+ NumRegs = 3;
+ Offset = 0;
+ Stride = 2;
+ return true;
+
+ case ARM::VLD3q8b:
+ case ARM::VLD3q16b:
+ case ARM::VLD3q32b:
+ FirstOpnd = 0;
+ NumRegs = 3;
+ Offset = 1;
+ Stride = 2;
+ return true;
+
+ case ARM::VLD3LNq16a:
+ case ARM::VLD3LNq32a:
+ FirstOpnd = 0;
+ NumRegs = 3;
+ Offset = 0;
+ Stride = 2;
+ return true;
+
+ case ARM::VLD3LNq16b:
+ case ARM::VLD3LNq32b:
+ FirstOpnd = 0;
+ NumRegs = 3;
+ Offset = 1;
+ Stride = 2;
+ return true;
+
+ case ARM::VLD4d8:
+ case ARM::VLD4d16:
+ case ARM::VLD4d32:
+ case ARM::VLD4d64:
+ case ARM::VLD4LNd8:
+ case ARM::VLD4LNd16:
+ case ARM::VLD4LNd32:
+ FirstOpnd = 0;
+ NumRegs = 4;
+ return true;
+
+ case ARM::VLD4q8a:
+ case ARM::VLD4q16a:
+ case ARM::VLD4q32a:
+ FirstOpnd = 0;
+ NumRegs = 4;
+ Offset = 0;
+ Stride = 2;
+ return true;
+
+ case ARM::VLD4q8b:
+ case ARM::VLD4q16b:
+ case ARM::VLD4q32b:
+ FirstOpnd = 0;
+ NumRegs = 4;
+ Offset = 1;
+ Stride = 2;
+ return true;
+
+ case ARM::VLD4LNq16a:
+ case ARM::VLD4LNq32a:
+ FirstOpnd = 0;
+ NumRegs = 4;
+ Offset = 0;
+ Stride = 2;
+ return true;
+
+ case ARM::VLD4LNq16b:
+ case ARM::VLD4LNq32b:
+ FirstOpnd = 0;
+ NumRegs = 4;
+ Offset = 1;
+ Stride = 2;
+ return true;
+
+ case ARM::VST2d8:
+ case ARM::VST2d16:
+ case ARM::VST2d32:
+ case ARM::VST2d64:
+ case ARM::VST2LNd8:
+ case ARM::VST2LNd16:
+ case ARM::VST2LNd32:
+ FirstOpnd = 3;
+ NumRegs = 2;
+ return true;
+
+ case ARM::VST2q8:
+ case ARM::VST2q16:
+ case ARM::VST2q32:
+ FirstOpnd = 3;
+ NumRegs = 4;
+ return true;
+
+ case ARM::VST2LNq16a:
+ case ARM::VST2LNq32a:
+ FirstOpnd = 3;
+ NumRegs = 2;
+ Offset = 0;
+ Stride = 2;
+ return true;
+
+ case ARM::VST2LNq16b:
+ case ARM::VST2LNq32b:
+ FirstOpnd = 3;
+ NumRegs = 2;
+ Offset = 1;
+ Stride = 2;
+ return true;
+
+ case ARM::VST3d8:
+ case ARM::VST3d16:
+ case ARM::VST3d32:
+ case ARM::VST3d64:
+ case ARM::VST3LNd8:
+ case ARM::VST3LNd16:
+ case ARM::VST3LNd32:
+ FirstOpnd = 3;
+ NumRegs = 3;
+ return true;
+
+ case ARM::VST3q8a:
+ case ARM::VST3q16a:
+ case ARM::VST3q32a:
+ FirstOpnd = 4;
+ NumRegs = 3;
+ Offset = 0;
+ Stride = 2;
+ return true;
+
+ case ARM::VST3q8b:
+ case ARM::VST3q16b:
+ case ARM::VST3q32b:
+ FirstOpnd = 4;
+ NumRegs = 3;
+ Offset = 1;
+ Stride = 2;
+ return true;
+
+ case ARM::VST3LNq16a:
+ case ARM::VST3LNq32a:
+ FirstOpnd = 3;
+ NumRegs = 3;
+ Offset = 0;
+ Stride = 2;
+ return true;
+
+ case ARM::VST3LNq16b:
+ case ARM::VST3LNq32b:
+ FirstOpnd = 3;
+ NumRegs = 3;
+ Offset = 1;
+ Stride = 2;
+ return true;
+
+ case ARM::VST4d8:
+ case ARM::VST4d16:
+ case ARM::VST4d32:
+ case ARM::VST4d64:
+ case ARM::VST4LNd8:
+ case ARM::VST4LNd16:
+ case ARM::VST4LNd32:
+ FirstOpnd = 3;
+ NumRegs = 4;
+ return true;
+
+ case ARM::VST4q8a:
+ case ARM::VST4q16a:
+ case ARM::VST4q32a:
+ FirstOpnd = 4;
+ NumRegs = 4;
+ Offset = 0;
+ Stride = 2;
+ return true;
+
+ case ARM::VST4q8b:
+ case ARM::VST4q16b:
+ case ARM::VST4q32b:
+ FirstOpnd = 4;
+ NumRegs = 4;
+ Offset = 1;
+ Stride = 2;
+ return true;
+
+ case ARM::VST4LNq16a:
+ case ARM::VST4LNq32a:
+ FirstOpnd = 3;
+ NumRegs = 4;
+ Offset = 0;
+ Stride = 2;
+ return true;
+
+ case ARM::VST4LNq16b:
+ case ARM::VST4LNq32b:
+ FirstOpnd = 3;
+ NumRegs = 4;
+ Offset = 1;
+ Stride = 2;
+ return true;
+
+ case ARM::VTBL2:
+ FirstOpnd = 1;
+ NumRegs = 2;
+ return true;
+
+ case ARM::VTBL3:
+ FirstOpnd = 1;
+ NumRegs = 3;
+ return true;
+
+ case ARM::VTBL4:
+ FirstOpnd = 1;
+ NumRegs = 4;
+ return true;
+
+ case ARM::VTBX2:
+ FirstOpnd = 2;
+ NumRegs = 2;
+ return true;
+
+ case ARM::VTBX3:
+ FirstOpnd = 2;
+ NumRegs = 3;
+ return true;
+
+ case ARM::VTBX4:
+ FirstOpnd = 2;
+ NumRegs = 4;
+ return true;
+ }
+
+ return false;
+}
+
+bool NEONPreAllocPass::PreAllocNEONRegisters(MachineBasicBlock &MBB) {
+ bool Modified = false;
+
+ MachineBasicBlock::iterator MBBI = MBB.begin(), E = MBB.end();
+ for (; MBBI != E; ++MBBI) {
+ MachineInstr *MI = &*MBBI;
+ unsigned FirstOpnd, NumRegs, Offset, Stride;
+ if (!isNEONMultiRegOp(MI->getOpcode(), FirstOpnd, NumRegs, Offset, Stride))
+ continue;
+
+ MachineBasicBlock::iterator NextI = next(MBBI);
+ for (unsigned R = 0; R < NumRegs; ++R) {
+ MachineOperand &MO = MI->getOperand(FirstOpnd + R);
+ assert(MO.isReg() && MO.getSubReg() == 0 && "unexpected operand");
+ unsigned VirtReg = MO.getReg();
+ assert(TargetRegisterInfo::isVirtualRegister(VirtReg) &&
+ "expected a virtual register");
+
+ // For now, just assign a fixed set of adjacent registers.
+ // This leaves plenty of room for future improvements.
+ static const unsigned NEONDRegs[] = {
+ ARM::D0, ARM::D1, ARM::D2, ARM::D3,
+ ARM::D4, ARM::D5, ARM::D6, ARM::D7
+ };
+ MO.setReg(NEONDRegs[Offset + R * Stride]);
+
+ if (MO.isUse()) {
+ // Insert a copy from VirtReg.
+ TII->copyRegToReg(MBB, MBBI, MO.getReg(), VirtReg,
+ ARM::DPRRegisterClass, ARM::DPRRegisterClass);
+ if (MO.isKill()) {
+ MachineInstr *CopyMI = prior(MBBI);
+ CopyMI->findRegisterUseOperand(VirtReg)->setIsKill();
+ }
+ MO.setIsKill();
+ } else if (MO.isDef() && !MO.isDead()) {
+ // Add a copy to VirtReg.
+ TII->copyRegToReg(MBB, NextI, VirtReg, MO.getReg(),
+ ARM::DPRRegisterClass, ARM::DPRRegisterClass);
+ }
+ }
+ }
+
+ return Modified;
+}
+
+bool NEONPreAllocPass::runOnMachineFunction(MachineFunction &MF) {
+ TII = MF.getTarget().getInstrInfo();
+
+ bool Modified = false;
+ for (MachineFunction::iterator MFI = MF.begin(), E = MF.end(); MFI != E;
+ ++MFI) {
+ MachineBasicBlock &MBB = *MFI;
+ Modified |= PreAllocNEONRegisters(MBB);
+ }
+
+ return Modified;
+}
+
+/// createNEONPreAllocPass - returns an instance of the NEON register
+/// pre-allocation pass.
+FunctionPass *llvm::createNEONPreAllocPass() {
+ return new NEONPreAllocPass();
+}
OpenPOWER on IntegriCloud