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-rw-r--r--contrib/llvm/lib/CodeGen/ProcessImplicitDefs.cpp165
1 files changed, 0 insertions, 165 deletions
diff --git a/contrib/llvm/lib/CodeGen/ProcessImplicitDefs.cpp b/contrib/llvm/lib/CodeGen/ProcessImplicitDefs.cpp
deleted file mode 100644
index b38987ad1c90..000000000000
--- a/contrib/llvm/lib/CodeGen/ProcessImplicitDefs.cpp
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@@ -1,165 +0,0 @@
-//===---------------------- ProcessImplicitDefs.cpp -----------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/ADT/SetVector.h"
-#include "llvm/Analysis/AliasAnalysis.h"
-#include "llvm/CodeGen/MachineFunctionPass.h"
-#include "llvm/CodeGen/MachineInstr.h"
-#include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/CodeGen/Passes.h"
-#include "llvm/CodeGen/TargetInstrInfo.h"
-#include "llvm/CodeGen/TargetSubtargetInfo.h"
-#include "llvm/Support/Debug.h"
-#include "llvm/Support/raw_ostream.h"
-
-using namespace llvm;
-
-#define DEBUG_TYPE "processimpdefs"
-
-namespace {
-/// Process IMPLICIT_DEF instructions and make sure there is one implicit_def
-/// for each use. Add isUndef marker to implicit_def defs and their uses.
-class ProcessImplicitDefs : public MachineFunctionPass {
- const TargetInstrInfo *TII;
- const TargetRegisterInfo *TRI;
- MachineRegisterInfo *MRI;
-
- SmallSetVector<MachineInstr*, 16> WorkList;
-
- void processImplicitDef(MachineInstr *MI);
- bool canTurnIntoImplicitDef(MachineInstr *MI);
-
-public:
- static char ID;
-
- ProcessImplicitDefs() : MachineFunctionPass(ID) {
- initializeProcessImplicitDefsPass(*PassRegistry::getPassRegistry());
- }
-
- void getAnalysisUsage(AnalysisUsage &au) const override;
-
- bool runOnMachineFunction(MachineFunction &MF) override;
-};
-} // end anonymous namespace
-
-char ProcessImplicitDefs::ID = 0;
-char &llvm::ProcessImplicitDefsID = ProcessImplicitDefs::ID;
-
-INITIALIZE_PASS(ProcessImplicitDefs, DEBUG_TYPE,
- "Process Implicit Definitions", false, false)
-
-void ProcessImplicitDefs::getAnalysisUsage(AnalysisUsage &AU) const {
- AU.setPreservesCFG();
- AU.addPreserved<AAResultsWrapperPass>();
- MachineFunctionPass::getAnalysisUsage(AU);
-}
-
-bool ProcessImplicitDefs::canTurnIntoImplicitDef(MachineInstr *MI) {
- if (!MI->isCopyLike() &&
- !MI->isInsertSubreg() &&
- !MI->isRegSequence() &&
- !MI->isPHI())
- return false;
- for (const MachineOperand &MO : MI->operands())
- if (MO.isReg() && MO.isUse() && MO.readsReg())
- return false;
- return true;
-}
-
-void ProcessImplicitDefs::processImplicitDef(MachineInstr *MI) {
- LLVM_DEBUG(dbgs() << "Processing " << *MI);
- unsigned Reg = MI->getOperand(0).getReg();
-
- if (TargetRegisterInfo::isVirtualRegister(Reg)) {
- // For virtual registers, mark all uses as <undef>, and convert users to
- // implicit-def when possible.
- for (MachineOperand &MO : MRI->use_nodbg_operands(Reg)) {
- MO.setIsUndef();
- MachineInstr *UserMI = MO.getParent();
- if (!canTurnIntoImplicitDef(UserMI))
- continue;
- LLVM_DEBUG(dbgs() << "Converting to IMPLICIT_DEF: " << *UserMI);
- UserMI->setDesc(TII->get(TargetOpcode::IMPLICIT_DEF));
- WorkList.insert(UserMI);
- }
- MI->eraseFromParent();
- return;
- }
-
- // This is a physreg implicit-def.
- // Look for the first instruction to use or define an alias.
- MachineBasicBlock::instr_iterator UserMI = MI->getIterator();
- MachineBasicBlock::instr_iterator UserE = MI->getParent()->instr_end();
- bool Found = false;
- for (++UserMI; UserMI != UserE; ++UserMI) {
- for (MachineOperand &MO : UserMI->operands()) {
- if (!MO.isReg())
- continue;
- unsigned UserReg = MO.getReg();
- if (!TargetRegisterInfo::isPhysicalRegister(UserReg) ||
- !TRI->regsOverlap(Reg, UserReg))
- continue;
- // UserMI uses or redefines Reg. Set <undef> flags on all uses.
- Found = true;
- if (MO.isUse())
- MO.setIsUndef();
- }
- if (Found)
- break;
- }
-
- // If we found the using MI, we can erase the IMPLICIT_DEF.
- if (Found) {
- LLVM_DEBUG(dbgs() << "Physreg user: " << *UserMI);
- MI->eraseFromParent();
- return;
- }
-
- // Using instr wasn't found, it could be in another block.
- // Leave the physreg IMPLICIT_DEF, but trim any extra operands.
- for (unsigned i = MI->getNumOperands() - 1; i; --i)
- MI->RemoveOperand(i);
- LLVM_DEBUG(dbgs() << "Keeping physreg: " << *MI);
-}
-
-/// processImplicitDefs - Process IMPLICIT_DEF instructions and turn them into
-/// <undef> operands.
-bool ProcessImplicitDefs::runOnMachineFunction(MachineFunction &MF) {
-
- LLVM_DEBUG(dbgs() << "********** PROCESS IMPLICIT DEFS **********\n"
- << "********** Function: " << MF.getName() << '\n');
-
- bool Changed = false;
-
- TII = MF.getSubtarget().getInstrInfo();
- TRI = MF.getSubtarget().getRegisterInfo();
- MRI = &MF.getRegInfo();
- assert(MRI->isSSA() && "ProcessImplicitDefs only works on SSA form.");
- assert(WorkList.empty() && "Inconsistent worklist state");
-
- for (MachineFunction::iterator MFI = MF.begin(), MFE = MF.end();
- MFI != MFE; ++MFI) {
- // Scan the basic block for implicit defs.
- for (MachineBasicBlock::instr_iterator MBBI = MFI->instr_begin(),
- MBBE = MFI->instr_end(); MBBI != MBBE; ++MBBI)
- if (MBBI->isImplicitDef())
- WorkList.insert(&*MBBI);
-
- if (WorkList.empty())
- continue;
-
- LLVM_DEBUG(dbgs() << printMBBReference(*MFI) << " has " << WorkList.size()
- << " implicit defs.\n");
- Changed = true;
-
- // Drain the WorkList to recursively process any new implicit defs.
- do processImplicitDef(WorkList.pop_back_val());
- while (!WorkList.empty());
- }
- return Changed;
-}