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diff --git a/contrib/llvm/lib/CodeGen/ExpandPostRAPseudos.cpp b/contrib/llvm/lib/CodeGen/ExpandPostRAPseudos.cpp
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+//===-- ExpandPostRAPseudos.cpp - Pseudo instruction expansion pass -------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines a pass that expands COPY and SUBREG_TO_REG pseudo
+// instructions after register allocation.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "postrapseudos"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/Function.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+using namespace llvm;
+
+namespace {
+struct ExpandPostRA : public MachineFunctionPass {
+private:
+ const TargetRegisterInfo *TRI;
+ const TargetInstrInfo *TII;
+
+public:
+ static char ID; // Pass identification, replacement for typeid
+ ExpandPostRA() : MachineFunctionPass(ID) {}
+
+ const char *getPassName() const {
+ return "Post-RA pseudo instruction expansion pass";
+ }
+
+ virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.setPreservesCFG();
+ AU.addPreservedID(MachineLoopInfoID);
+ AU.addPreservedID(MachineDominatorsID);
+ MachineFunctionPass::getAnalysisUsage(AU);
+ }
+
+ /// runOnMachineFunction - pass entry point
+ bool runOnMachineFunction(MachineFunction&);
+
+private:
+ bool LowerSubregToReg(MachineInstr *MI);
+ bool LowerCopy(MachineInstr *MI);
+
+ void TransferDeadFlag(MachineInstr *MI, unsigned DstReg,
+ const TargetRegisterInfo *TRI);
+ void TransferImplicitDefs(MachineInstr *MI);
+};
+} // end anonymous namespace
+
+char ExpandPostRA::ID = 0;
+
+FunctionPass *llvm::createExpandPostRAPseudosPass() {
+ return new ExpandPostRA();
+}
+
+/// TransferDeadFlag - MI is a pseudo-instruction with DstReg dead,
+/// and the lowered replacement instructions immediately precede it.
+/// Mark the replacement instructions with the dead flag.
+void
+ExpandPostRA::TransferDeadFlag(MachineInstr *MI, unsigned DstReg,
+ const TargetRegisterInfo *TRI) {
+ for (MachineBasicBlock::iterator MII =
+ prior(MachineBasicBlock::iterator(MI)); ; --MII) {
+ if (MII->addRegisterDead(DstReg, TRI))
+ break;
+ assert(MII != MI->getParent()->begin() &&
+ "copyPhysReg output doesn't reference destination register!");
+ }
+}
+
+/// TransferImplicitDefs - MI is a pseudo-instruction, and the lowered
+/// replacement instructions immediately precede it. Copy any implicit-def
+/// operands from MI to the replacement instruction.
+void
+ExpandPostRA::TransferImplicitDefs(MachineInstr *MI) {
+ MachineBasicBlock::iterator CopyMI = MI;
+ --CopyMI;
+
+ for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
+ MachineOperand &MO = MI->getOperand(i);
+ if (!MO.isReg() || !MO.isImplicit() || MO.isUse())
+ continue;
+ CopyMI->addOperand(MachineOperand::CreateReg(MO.getReg(), true, true));
+ }
+}
+
+bool ExpandPostRA::LowerSubregToReg(MachineInstr *MI) {
+ MachineBasicBlock *MBB = MI->getParent();
+ assert((MI->getOperand(0).isReg() && MI->getOperand(0).isDef()) &&
+ MI->getOperand(1).isImm() &&
+ (MI->getOperand(2).isReg() && MI->getOperand(2).isUse()) &&
+ MI->getOperand(3).isImm() && "Invalid subreg_to_reg");
+
+ unsigned DstReg = MI->getOperand(0).getReg();
+ unsigned InsReg = MI->getOperand(2).getReg();
+ assert(!MI->getOperand(2).getSubReg() && "SubIdx on physreg?");
+ unsigned SubIdx = MI->getOperand(3).getImm();
+
+ assert(SubIdx != 0 && "Invalid index for insert_subreg");
+ unsigned DstSubReg = TRI->getSubReg(DstReg, SubIdx);
+
+ assert(TargetRegisterInfo::isPhysicalRegister(DstReg) &&
+ "Insert destination must be in a physical register");
+ assert(TargetRegisterInfo::isPhysicalRegister(InsReg) &&
+ "Inserted value must be in a physical register");
+
+ DEBUG(dbgs() << "subreg: CONVERTING: " << *MI);
+
+ if (DstSubReg == InsReg) {
+ // No need to insert an identify copy instruction.
+ // Watch out for case like this:
+ // %RAX<def> = SUBREG_TO_REG 0, %EAX<kill>, 3
+ // We must leave %RAX live.
+ if (DstReg != InsReg) {
+ MI->setDesc(TII->get(TargetOpcode::KILL));
+ MI->RemoveOperand(3); // SubIdx
+ MI->RemoveOperand(1); // Imm
+ DEBUG(dbgs() << "subreg: replace by: " << *MI);
+ return true;
+ }
+ DEBUG(dbgs() << "subreg: eliminated!");
+ } else {
+ TII->copyPhysReg(*MBB, MI, MI->getDebugLoc(), DstSubReg, InsReg,
+ MI->getOperand(2).isKill());
+ // Transfer the kill/dead flags, if needed.
+ if (MI->getOperand(0).isDead())
+ TransferDeadFlag(MI, DstSubReg, TRI);
+ DEBUG({
+ MachineBasicBlock::iterator dMI = MI;
+ dbgs() << "subreg: " << *(--dMI);
+ });
+ }
+
+ DEBUG(dbgs() << '\n');
+ MBB->erase(MI);
+ return true;
+}
+
+bool ExpandPostRA::LowerCopy(MachineInstr *MI) {
+ MachineOperand &DstMO = MI->getOperand(0);
+ MachineOperand &SrcMO = MI->getOperand(1);
+
+ if (SrcMO.getReg() == DstMO.getReg()) {
+ DEBUG(dbgs() << "identity copy: " << *MI);
+ // No need to insert an identity copy instruction, but replace with a KILL
+ // if liveness is changed.
+ if (DstMO.isDead() || SrcMO.isUndef() || MI->getNumOperands() > 2) {
+ // We must make sure the super-register gets killed. Replace the
+ // instruction with KILL.
+ MI->setDesc(TII->get(TargetOpcode::KILL));
+ DEBUG(dbgs() << "replaced by: " << *MI);
+ return true;
+ }
+ // Vanilla identity copy.
+ MI->eraseFromParent();
+ return true;
+ }
+
+ DEBUG(dbgs() << "real copy: " << *MI);
+ TII->copyPhysReg(*MI->getParent(), MI, MI->getDebugLoc(),
+ DstMO.getReg(), SrcMO.getReg(), SrcMO.isKill());
+
+ if (DstMO.isDead())
+ TransferDeadFlag(MI, DstMO.getReg(), TRI);
+ if (MI->getNumOperands() > 2)
+ TransferImplicitDefs(MI);
+ DEBUG({
+ MachineBasicBlock::iterator dMI = MI;
+ dbgs() << "replaced by: " << *(--dMI);
+ });
+ MI->eraseFromParent();
+ return true;
+}
+
+/// runOnMachineFunction - Reduce subregister inserts and extracts to register
+/// copies.
+///
+bool ExpandPostRA::runOnMachineFunction(MachineFunction &MF) {
+ DEBUG(dbgs() << "Machine Function\n"
+ << "********** EXPANDING POST-RA PSEUDO INSTRS **********\n"
+ << "********** Function: "
+ << MF.getFunction()->getName() << '\n');
+ TRI = MF.getTarget().getRegisterInfo();
+ TII = MF.getTarget().getInstrInfo();
+
+ bool MadeChange = false;
+
+ for (MachineFunction::iterator mbbi = MF.begin(), mbbe = MF.end();
+ mbbi != mbbe; ++mbbi) {
+ for (MachineBasicBlock::iterator mi = mbbi->begin(), me = mbbi->end();
+ mi != me;) {
+ MachineInstr *MI = mi;
+ // Advance iterator here because MI may be erased.
+ ++mi;
+
+ // Only expand pseudos.
+ if (!MI->getDesc().isPseudo())
+ continue;
+
+ // Give targets a chance to expand even standard pseudos.
+ if (TII->expandPostRAPseudo(MI)) {
+ MadeChange = true;
+ continue;
+ }
+
+ // Expand standard pseudos.
+ switch (MI->getOpcode()) {
+ case TargetOpcode::SUBREG_TO_REG:
+ MadeChange |= LowerSubregToReg(MI);
+ break;
+ case TargetOpcode::COPY:
+ MadeChange |= LowerCopy(MI);
+ break;
+ case TargetOpcode::DBG_VALUE:
+ continue;
+ case TargetOpcode::INSERT_SUBREG:
+ case TargetOpcode::EXTRACT_SUBREG:
+ llvm_unreachable("Sub-register pseudos should have been eliminated.");
+ }
+ }
+ }
+
+ return MadeChange;
+}
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