mirror of
https://github.com/c64scene-ar/llvm-6502.git
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Revert "Convert liveness tracking to work on a sub-register level instead of just register units."
This reverts commit r197253. This was a great change, but Juergen should be the commit author. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197262 91177308-0d34-0410-b5e6-96231b3b80d8
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@ -1,119 +0,0 @@
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//===- llvm/CodeGen/LivePhysRegs.h - Live Physical Register Set -*- C++ -*-===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements a set of live physical registers. This can be used for
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// ad hoc liveness tracking after register allocation. You can start with the
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// live-ins/live-outs at the beginning/end of a block and update the information
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// while walking the instructions inside the block.
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_CODEGEN_LIVE_PHYS_REGS_H
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#define LLVM_CODEGEN_LIVE_PHYS_REGS_H
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#include "llvm/ADT/SparseSet.h"
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#include "llvm/CodeGen/MachineBasicBlock.h"
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#include "llvm/Target/TargetRegisterInfo.h"
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#include <cassert>
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namespace llvm {
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class MachineInstr;
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/// \brief A set of live physical registers with functions to track liveness
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/// when walking backward/forward through a basic block.
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class LivePhysRegs {
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const TargetRegisterInfo *TRI;
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SparseSet<unsigned> LiveRegs;
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LivePhysRegs(const LivePhysRegs&) LLVM_DELETED_FUNCTION;
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LivePhysRegs &operator=(const LivePhysRegs&) LLVM_DELETED_FUNCTION;
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public:
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/// \brief Constructs a new empty LivePhysRegs set.
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LivePhysRegs() : TRI(0), LiveRegs() {}
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/// \brief Constructs and initialize an empty LivePhysRegs set.
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LivePhysRegs(const TargetRegisterInfo *TRI) : TRI(TRI) {
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LiveRegs.setUniverse(TRI->getNumRegs());
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}
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/// \brief Clear and initialize the LivePhysRegs set.
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void init(const TargetRegisterInfo *_TRI) {
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TRI = _TRI;
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LiveRegs.clear();
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LiveRegs.setUniverse(TRI->getNumRegs());
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}
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/// \brief Clears the LivePhysRegs set.
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void clear() { LiveRegs.clear(); }
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/// \brief Returns true if the set is empty.
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bool empty() const { return LiveRegs.empty(); }
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/// \brief Adds a physical register and all its sub-registers to the set.
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void addReg(unsigned Reg) {
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assert(TRI && "LivePhysRegs is not initialized.");
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for (MCSubRegIterator SubRegs(Reg, TRI, /*IncludeSelf=*/true);
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SubRegs.isValid(); ++SubRegs)
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LiveRegs.insert(*SubRegs);
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}
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/// \brief Removes a physical register, all its sub-registers, and all its
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/// super-registers from the set.
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void removeReg(unsigned Reg) {
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assert(TRI && "LivePhysRegs is not initialized.");
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for (MCSubRegIterator SubRegs(Reg, TRI, /*IncludeSelf=*/true);
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SubRegs.isValid(); ++SubRegs)
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LiveRegs.erase(*SubRegs);
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for (MCSuperRegIterator SuperRegs(Reg, TRI, /*IncludeSelf=*/false);
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SuperRegs.isValid(); ++SuperRegs)
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LiveRegs.erase(*SuperRegs);
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}
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/// \brief Removes physical registers clobbered by the regmask operand @p MO.
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void removeRegsInMask(const MachineOperand &MO);
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/// \brief Returns true if register @p Reg is contained in the set. This also
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/// works if only the super register of @p Reg has been defined, because we
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/// always add also all sub-registers to the set.
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bool contains(unsigned Reg) const { return LiveRegs.count(Reg); }
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/// \brief Simulates liveness when stepping backwards over an
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/// instruction(bundle): Remove Defs, add uses. This is the recommended way of
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/// calculating liveness.
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void stepBackward(const MachineInstr &MI);
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/// \brief Simulates liveness when stepping forward over an
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/// instruction(bundle): Remove killed-uses, add defs. This is the not
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/// recommended way, because it depends on accurate kill flags. If possible
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/// use stepBackwards() instead of this function.
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void stepForward(const MachineInstr &MI);
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/// \brief Adds all live-in registers of basic block @p MBB.
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void addLiveIns(const MachineBasicBlock *MBB) {
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for (MachineBasicBlock::livein_iterator LI = MBB->livein_begin(),
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LE = MBB->livein_end(); LI != LE; ++LI)
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addReg(*LI);
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}
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/// \brief Adds all live-out registers of basic block @p MBB.
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void addLiveOuts(const MachineBasicBlock *MBB) {
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for (MachineBasicBlock::const_succ_iterator SI = MBB->succ_begin(),
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SE = MBB->succ_end(); SI != SE; ++SI)
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addLiveIns(*SI);
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}
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typedef SparseSet<unsigned>::const_iterator const_iterator;
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const_iterator begin() const { return LiveRegs.begin(); }
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const_iterator end() const { return LiveRegs.end(); }
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};
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} // namespace llvm
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#endif
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88
include/llvm/CodeGen/LiveRegUnits.h
Normal file
88
include/llvm/CodeGen/LiveRegUnits.h
Normal file
@ -0,0 +1,88 @@
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//===-- llvm/CodeGen/LiveRegUnits.h - Live register unit set ----*- C++ -*-===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements a Set of live register units. This can be used for ad
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// hoc liveness tracking after register allocation. You can start with the
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// live-ins/live-outs at the beginning/end of a block and update the information
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// while walking the instructions inside the block.
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_CODEGEN_LIVEREGUNITS_H
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#define LLVM_CODEGEN_LIVEREGUNITS_H
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#include "llvm/ADT/SparseSet.h"
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#include "llvm/CodeGen/MachineBasicBlock.h"
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#include "llvm/Target/TargetRegisterInfo.h"
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#include <cassert>
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namespace llvm {
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class MachineInstr;
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/// A set of live register units with functions to track liveness when walking
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/// backward/forward through a basic block.
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class LiveRegUnits {
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SparseSet<unsigned> LiveUnits;
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LiveRegUnits(const LiveRegUnits&) LLVM_DELETED_FUNCTION;
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LiveRegUnits &operator=(const LiveRegUnits&) LLVM_DELETED_FUNCTION;
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public:
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/// \brief Constructs a new empty LiveRegUnits set.
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LiveRegUnits() {}
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void init(const TargetRegisterInfo *TRI) {
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LiveUnits.clear();
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LiveUnits.setUniverse(TRI->getNumRegs());
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}
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void clear() { LiveUnits.clear(); }
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bool empty() const { return LiveUnits.empty(); }
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/// \brief Adds a register to the set.
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void addReg(unsigned Reg, const MCRegisterInfo &MCRI) {
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for (MCRegUnitIterator RUnits(Reg, &MCRI); RUnits.isValid(); ++RUnits)
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LiveUnits.insert(*RUnits);
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}
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/// \brief Removes a register from the set.
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void removeReg(unsigned Reg, const MCRegisterInfo &MCRI) {
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for (MCRegUnitIterator RUnits(Reg, &MCRI); RUnits.isValid(); ++RUnits)
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LiveUnits.erase(*RUnits);
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}
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/// \brief Removes registers clobbered by the regmask operand @p Op.
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void removeRegsInMask(const MachineOperand &Op, const MCRegisterInfo &MCRI);
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/// \brief Returns true if register @p Reg (or one of its super register) is
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/// contained in the set.
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bool contains(unsigned Reg, const MCRegisterInfo &MCRI) const {
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for (MCRegUnitIterator RUnits(Reg, &MCRI); RUnits.isValid(); ++RUnits) {
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if (LiveUnits.count(*RUnits))
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return true;
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}
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return false;
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}
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/// \brief Simulates liveness when stepping backwards over an
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/// instruction(bundle): Remove Defs, add uses.
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void stepBackward(const MachineInstr &MI, const MCRegisterInfo &MCRI);
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/// \brief Simulates liveness when stepping forward over an
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/// instruction(bundle): Remove killed-uses, add defs.
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void stepForward(const MachineInstr &MI, const MCRegisterInfo &MCRI);
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/// \brief Adds all registers in the live-in list of block @p BB.
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void addLiveIns(const MachineBasicBlock *MBB, const MCRegisterInfo &MCRI);
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};
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} // namespace llvm
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#endif
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@ -35,7 +35,7 @@ add_llvm_library(LLVMCodeGen
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LiveRangeCalc.cpp
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LiveRangeEdit.cpp
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LiveRegMatrix.cpp
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LivePhysRegs.cpp
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LiveRegUnits.cpp
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LiveStackAnalysis.cpp
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LiveVariables.cpp
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LocalStackSlotAllocation.cpp
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@ -23,7 +23,7 @@
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#define DEBUG_TYPE "execution-fix"
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#include "llvm/CodeGen/Passes.h"
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#include "llvm/ADT/PostOrderIterator.h"
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#include "llvm/CodeGen/LivePhysRegs.h"
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#include "llvm/CodeGen/LiveRegUnits.h"
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#include "llvm/CodeGen/MachineFunctionPass.h"
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#include "llvm/CodeGen/MachineRegisterInfo.h"
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#include "llvm/Support/Allocator.h"
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@ -141,7 +141,7 @@ class ExeDepsFix : public MachineFunctionPass {
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std::vector<std::pair<MachineInstr*, unsigned> > UndefReads;
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/// Storage for register unit liveness.
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LivePhysRegs LiveRegSet;
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LiveRegUnits LiveUnits;
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/// Current instruction number.
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/// The first instruction in each basic block is 0.
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@ -352,7 +352,7 @@ void ExeDepsFix::enterBasicBlock(MachineBasicBlock *MBB) {
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// Set up UndefReads to track undefined register reads.
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UndefReads.clear();
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LiveRegSet.clear();
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LiveUnits.clear();
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// Set up LiveRegs to represent registers entering MBB.
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if (!LiveRegs)
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@ -547,19 +547,21 @@ void ExeDepsFix::processUndefReads(MachineBasicBlock *MBB) {
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return;
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// Collect this block's live out register units.
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LiveRegSet.init(TRI);
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LiveRegSet.addLiveOuts(MBB);
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LiveUnits.init(TRI);
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for (MachineBasicBlock::const_succ_iterator SI = MBB->succ_begin(),
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SE = MBB->succ_end(); SI != SE; ++SI) {
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LiveUnits.addLiveIns(*SI, *TRI);
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}
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MachineInstr *UndefMI = UndefReads.back().first;
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unsigned OpIdx = UndefReads.back().second;
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for (MachineBasicBlock::reverse_iterator I = MBB->rbegin(), E = MBB->rend();
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I != E; ++I) {
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// Update liveness, including the current instrucion's defs.
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LiveRegSet.stepBackward(*I);
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LiveUnits.stepBackward(*I, *TRI);
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if (UndefMI == &*I) {
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if (!LiveRegSet.contains(UndefMI->getOperand(OpIdx).getReg()))
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if (!LiveUnits.contains(UndefMI->getOperand(OpIdx).getReg(), *TRI))
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TII->breakPartialRegDependency(UndefMI, OpIdx, TRI);
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UndefReads.pop_back();
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@ -23,7 +23,7 @@
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#include "llvm/CodeGen/MachineModuleInfo.h"
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#include "llvm/CodeGen/MachineRegisterInfo.h"
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#include "llvm/CodeGen/TargetSchedule.h"
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#include "llvm/CodeGen/LivePhysRegs.h"
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#include "llvm/CodeGen/LiveRegUnits.h"
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#include "llvm/MC/MCInstrItineraries.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/Debug.h"
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@ -162,8 +162,8 @@ namespace {
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const MachineBranchProbabilityInfo *MBPI;
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MachineRegisterInfo *MRI;
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LivePhysRegs Redefs;
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LivePhysRegs DontKill;
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LiveRegUnits Redefs;
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LiveRegUnits DontKill;
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bool PreRegAlloc;
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bool MadeChange;
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@ -968,22 +968,23 @@ void IfConverter::RemoveExtraEdges(BBInfo &BBI) {
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/// Behaves like LiveRegUnits::StepForward() but also adds implicit uses to all
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/// values defined in MI which are not live/used by MI.
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static void UpdatePredRedefs(MachineInstr *MI, LivePhysRegs &Redefs) {
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static void UpdatePredRedefs(MachineInstr *MI, LiveRegUnits &Redefs,
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const TargetRegisterInfo *TRI) {
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for (ConstMIBundleOperands Ops(MI); Ops.isValid(); ++Ops) {
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if (!Ops->isReg() || !Ops->isKill())
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continue;
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unsigned Reg = Ops->getReg();
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if (Reg == 0)
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continue;
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Redefs.removeReg(Reg);
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Redefs.removeReg(Reg, *TRI);
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}
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for (MIBundleOperands Ops(MI); Ops.isValid(); ++Ops) {
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if (!Ops->isReg() || !Ops->isDef())
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continue;
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unsigned Reg = Ops->getReg();
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if (Reg == 0 || Redefs.contains(Reg))
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if (Reg == 0 || Redefs.contains(Reg, *TRI))
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continue;
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Redefs.addReg(Reg);
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Redefs.addReg(Reg, *TRI);
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MachineOperand &Op = *Ops;
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MachineInstr *MI = Op.getParent();
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@ -995,11 +996,12 @@ static void UpdatePredRedefs(MachineInstr *MI, LivePhysRegs &Redefs) {
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/**
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* Remove kill flags from operands with a registers in the @p DontKill set.
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*/
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static void RemoveKills(MachineInstr &MI, const LivePhysRegs &DontKill) {
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static void RemoveKills(MachineInstr &MI, const LiveRegUnits &DontKill,
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const MCRegisterInfo &MCRI) {
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for (MIBundleOperands O(&MI); O.isValid(); ++O) {
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if (!O->isReg() || !O->isKill())
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continue;
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if (DontKill.contains(O->getReg()))
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if (DontKill.contains(O->getReg(), MCRI))
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O->setIsKill(false);
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}
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}
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@ -1010,10 +1012,10 @@ static void RemoveKills(MachineInstr &MI, const LivePhysRegs &DontKill) {
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*/
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static void RemoveKills(MachineBasicBlock::iterator I,
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MachineBasicBlock::iterator E,
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const LivePhysRegs &DontKill,
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const LiveRegUnits &DontKill,
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const MCRegisterInfo &MCRI) {
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for ( ; I != E; ++I)
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RemoveKills(*I, DontKill);
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RemoveKills(*I, DontKill, MCRI);
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}
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/// IfConvertSimple - If convert a simple (split, no rejoin) sub-CFG.
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@ -1047,13 +1049,13 @@ bool IfConverter::IfConvertSimple(BBInfo &BBI, IfcvtKind Kind) {
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// Initialize liveins to the first BB. These are potentiall redefined by
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// predicated instructions.
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Redefs.init(TRI);
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Redefs.addLiveIns(CvtBBI->BB);
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Redefs.addLiveIns(NextBBI->BB);
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Redefs.addLiveIns(CvtBBI->BB, *TRI);
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Redefs.addLiveIns(NextBBI->BB, *TRI);
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// Compute a set of registers which must not be killed by instructions in
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// BB1: This is everything live-in to BB2.
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DontKill.init(TRI);
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DontKill.addLiveIns(NextBBI->BB);
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DontKill.addLiveIns(NextBBI->BB, *TRI);
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if (CvtBBI->BB->pred_size() > 1) {
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BBI.NonPredSize -= TII->RemoveBranch(*BBI.BB);
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@ -1152,8 +1154,8 @@ bool IfConverter::IfConvertTriangle(BBInfo &BBI, IfcvtKind Kind) {
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// Initialize liveins to the first BB. These are potentially redefined by
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// predicated instructions.
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Redefs.init(TRI);
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Redefs.addLiveIns(CvtBBI->BB);
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Redefs.addLiveIns(NextBBI->BB);
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Redefs.addLiveIns(CvtBBI->BB, *TRI);
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Redefs.addLiveIns(NextBBI->BB, *TRI);
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DontKill.clear();
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@ -1282,7 +1284,7 @@ bool IfConverter::IfConvertDiamond(BBInfo &BBI, IfcvtKind Kind,
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// Initialize liveins to the first BB. These are potentially redefined by
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// predicated instructions.
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Redefs.init(TRI);
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Redefs.addLiveIns(BBI1->BB);
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Redefs.addLiveIns(BBI1->BB, *TRI);
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// Remove the duplicated instructions at the beginnings of both paths.
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MachineBasicBlock::iterator DI1 = BBI1->BB->begin();
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@ -1315,12 +1317,12 @@ bool IfConverter::IfConvertDiamond(BBInfo &BBI, IfcvtKind Kind,
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DontKill.init(TRI);
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for (MachineBasicBlock::reverse_iterator I = BBI2->BB->rbegin(),
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E = MachineBasicBlock::reverse_iterator(DI2); I != E; ++I) {
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DontKill.stepBackward(*I);
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DontKill.stepBackward(*I, *TRI);
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}
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for (MachineBasicBlock::const_iterator I = BBI1->BB->begin(), E = DI1; I != E;
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++I) {
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Redefs.stepForward(*I);
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Redefs.stepForward(*I, *TRI);
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}
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BBI.BB->splice(BBI.BB->end(), BBI1->BB, BBI1->BB->begin(), DI1);
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BBI2->BB->erase(BBI2->BB->begin(), DI2);
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@ -1504,7 +1506,7 @@ void IfConverter::PredicateBlock(BBInfo &BBI,
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// If the predicated instruction now redefines a register as the result of
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// if-conversion, add an implicit kill.
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UpdatePredRedefs(I, Redefs);
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UpdatePredRedefs(I, Redefs, TRI);
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}
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std::copy(Cond.begin(), Cond.end(), std::back_inserter(BBI.Predicate));
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@ -1550,11 +1552,11 @@ void IfConverter::CopyAndPredicateBlock(BBInfo &ToBBI, BBInfo &FromBBI,
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// If the predicated instruction now redefines a register as the result of
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// if-conversion, add an implicit kill.
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UpdatePredRedefs(MI, Redefs);
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UpdatePredRedefs(MI, Redefs, TRI);
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|
||||
// Some kill flags may not be correct anymore.
|
||||
if (!DontKill.empty())
|
||||
RemoveKills(*MI, DontKill);
|
||||
RemoveKills(*MI, DontKill, *TRI);
|
||||
}
|
||||
|
||||
if (!IgnoreBr) {
|
||||
|
@ -1,91 +0,0 @@
|
||||
//===--- LivePhysRegs.cpp - Live Physical Register Set --------------------===//
|
||||
//
|
||||
// The LLVM Compiler Infrastructure
|
||||
//
|
||||
// This file is distributed under the University of Illinois Open Source
|
||||
// License. See LICENSE.TXT for details.
|
||||
//
|
||||
//===----------------------------------------------------------------------===//
|
||||
//
|
||||
// This file implements the LivePhysRegs utility for tracking liveness of
|
||||
// physical registers across machine instructions in forward or backward order.
|
||||
//
|
||||
//===----------------------------------------------------------------------===//
|
||||
|
||||
#include "llvm/CodeGen/LivePhysRegs.h"
|
||||
#include "llvm/CodeGen/MachineInstrBundle.h"
|
||||
using namespace llvm;
|
||||
|
||||
|
||||
/// We assume the high bits of a physical super-register are not preserved
|
||||
/// unless the instruction has an implicit-use operand reading the
|
||||
/// super-register.
|
||||
|
||||
/// \brief Remove all registers from the set that get clobbered by the register
|
||||
/// mask.
|
||||
void LivePhysRegs::removeRegsInMask(const MachineOperand &MO) {
|
||||
SparseSet<unsigned>::iterator LRI = LiveRegs.begin();
|
||||
while (LRI != LiveRegs.end()) {
|
||||
if (MO.clobbersPhysReg(*LRI))
|
||||
LRI = LiveRegs.erase(LRI);
|
||||
else
|
||||
++LRI;
|
||||
}
|
||||
}
|
||||
|
||||
/// Simulates liveness when stepping backwards over an instruction(bundle):
|
||||
/// Remove Defs, add uses. This is the recommended way of calculating liveness.
|
||||
void LivePhysRegs::stepBackward(const MachineInstr &MI) {
|
||||
// Remove defined registers and regmask kills from the set.
|
||||
for (ConstMIBundleOperands O(&MI); O.isValid(); ++O) {
|
||||
if (O->isReg()) {
|
||||
if (!O->isDef())
|
||||
continue;
|
||||
unsigned Reg = O->getReg();
|
||||
if (Reg == 0)
|
||||
continue;
|
||||
removeReg(Reg);
|
||||
} else if (O->isRegMask())
|
||||
removeRegsInMask(*O);
|
||||
}
|
||||
|
||||
// Add uses to the set.
|
||||
for (ConstMIBundleOperands O(&MI); O.isValid(); ++O) {
|
||||
if (!O->isReg() || !O->readsReg() || O->isUndef())
|
||||
continue;
|
||||
unsigned Reg = O->getReg();
|
||||
if (Reg == 0)
|
||||
continue;
|
||||
addReg(Reg);
|
||||
}
|
||||
}
|
||||
|
||||
/// Simulates liveness when stepping forward over an instruction(bundle): Remove
|
||||
/// killed-uses, add defs. This is the not recommended way, because it depends
|
||||
/// on accurate kill flags. If possible use stepBackwards() instead of this
|
||||
/// function.
|
||||
void LivePhysRegs::stepForward(const MachineInstr &MI) {
|
||||
SmallVector<unsigned, 4> Defs;
|
||||
// Remove killed registers from the set.
|
||||
for (ConstMIBundleOperands O(&MI); O.isValid(); ++O) {
|
||||
if (O->isReg()) {
|
||||
unsigned Reg = O->getReg();
|
||||
if (Reg == 0)
|
||||
continue;
|
||||
if (O->isDef()) {
|
||||
if (!O->isDead())
|
||||
Defs.push_back(Reg);
|
||||
} else {
|
||||
if (!O->isKill())
|
||||
continue;
|
||||
assert(O->isUse());
|
||||
removeReg(Reg);
|
||||
}
|
||||
} else if (O->isRegMask())
|
||||
removeRegsInMask(*O);
|
||||
}
|
||||
|
||||
// Add defs to the set.
|
||||
for (unsigned i = 0, e = Defs.size(); i != e; ++i)
|
||||
addReg(Defs[i]);
|
||||
}
|
111
lib/CodeGen/LiveRegUnits.cpp
Normal file
111
lib/CodeGen/LiveRegUnits.cpp
Normal file
@ -0,0 +1,111 @@
|
||||
//===-- LiveInterval.cpp - Live Interval Representation -------------------===//
|
||||
//
|
||||
// The LLVM Compiler Infrastructure
|
||||
//
|
||||
// This file is distributed under the University of Illinois Open Source
|
||||
// License. See LICENSE.TXT for details.
|
||||
//
|
||||
//===----------------------------------------------------------------------===//
|
||||
//
|
||||
// This file implements the LiveRegUnits utility for tracking liveness of
|
||||
// physical register units across machine instructions in forward or backward
|
||||
// order.
|
||||
//
|
||||
//===----------------------------------------------------------------------===//
|
||||
|
||||
#include "llvm/CodeGen/LiveRegUnits.h"
|
||||
#include "llvm/CodeGen/MachineInstrBundle.h"
|
||||
using namespace llvm;
|
||||
|
||||
/// Return true if the given MachineOperand clobbers the given register unit.
|
||||
/// A register unit is only clobbered if all its super-registers are clobbered.
|
||||
static bool operClobbersUnit(const MachineOperand *MO, unsigned Unit,
|
||||
const MCRegisterInfo *MCRI) {
|
||||
for (MCRegUnitRootIterator RI(Unit, MCRI); RI.isValid(); ++RI) {
|
||||
for (MCSuperRegIterator SI(*RI, MCRI, true); SI.isValid(); ++SI) {
|
||||
if (!MO->clobbersPhysReg(*SI))
|
||||
return false;
|
||||
}
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
/// We assume the high bits of a physical super register are not preserved
|
||||
/// unless the instruction has an implicit-use operand reading the
|
||||
/// super-register or a register unit for the upper bits is available.
|
||||
void LiveRegUnits::removeRegsInMask(const MachineOperand &Op,
|
||||
const MCRegisterInfo &MCRI) {
|
||||
SparseSet<unsigned>::iterator LUI = LiveUnits.begin();
|
||||
while (LUI != LiveUnits.end()) {
|
||||
if (operClobbersUnit(&Op, *LUI, &MCRI))
|
||||
LUI = LiveUnits.erase(LUI);
|
||||
else
|
||||
++LUI;
|
||||
}
|
||||
}
|
||||
|
||||
void LiveRegUnits::stepBackward(const MachineInstr &MI,
|
||||
const MCRegisterInfo &MCRI) {
|
||||
// Remove defined registers and regmask kills from the set.
|
||||
for (ConstMIBundleOperands O(&MI); O.isValid(); ++O) {
|
||||
if (O->isReg()) {
|
||||
if (!O->isDef())
|
||||
continue;
|
||||
unsigned Reg = O->getReg();
|
||||
if (Reg == 0)
|
||||
continue;
|
||||
removeReg(Reg, MCRI);
|
||||
} else if (O->isRegMask()) {
|
||||
removeRegsInMask(*O, MCRI);
|
||||
}
|
||||
}
|
||||
// Add uses to the set.
|
||||
for (ConstMIBundleOperands O(&MI); O.isValid(); ++O) {
|
||||
if (!O->isReg() || !O->readsReg() || O->isUndef())
|
||||
continue;
|
||||
unsigned Reg = O->getReg();
|
||||
if (Reg == 0)
|
||||
continue;
|
||||
addReg(Reg, MCRI);
|
||||
}
|
||||
}
|
||||
|
||||
/// Uses with kill flag get removed from the set, defs added. If possible
|
||||
/// use StepBackward() instead of this function because some kill flags may
|
||||
/// be missing.
|
||||
void LiveRegUnits::stepForward(const MachineInstr &MI,
|
||||
const MCRegisterInfo &MCRI) {
|
||||
SmallVector<unsigned, 4> Defs;
|
||||
// Remove killed registers from the set.
|
||||
for (ConstMIBundleOperands O(&MI); O.isValid(); ++O) {
|
||||
if (O->isReg()) {
|
||||
unsigned Reg = O->getReg();
|
||||
if (Reg == 0)
|
||||
continue;
|
||||
if (O->isDef()) {
|
||||
if (!O->isDead())
|
||||
Defs.push_back(Reg);
|
||||
} else {
|
||||
if (!O->isKill())
|
||||
continue;
|
||||
assert(O->isUse());
|
||||
removeReg(Reg, MCRI);
|
||||
}
|
||||
} else if (O->isRegMask()) {
|
||||
removeRegsInMask(*O, MCRI);
|
||||
}
|
||||
}
|
||||
// Add defs to the set.
|
||||
for (unsigned i = 0, e = Defs.size(); i != e; ++i) {
|
||||
addReg(Defs[i], MCRI);
|
||||
}
|
||||
}
|
||||
|
||||
/// Adds all registers in the live-in list of block @p BB.
|
||||
void LiveRegUnits::addLiveIns(const MachineBasicBlock *MBB,
|
||||
const MCRegisterInfo &MCRI) {
|
||||
for (MachineBasicBlock::livein_iterator L = MBB->livein_begin(),
|
||||
LE = MBB->livein_end(); L != LE; ++L) {
|
||||
addReg(*L, MCRI);
|
||||
}
|
||||
}
|
Loading…
Reference in New Issue
Block a user