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-rw-r--r--lib/Target/PowerPC/PPCMachineBasicBlockUtils.h198
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diff --git a/lib/Target/PowerPC/PPCMachineBasicBlockUtils.h b/lib/Target/PowerPC/PPCMachineBasicBlockUtils.h
deleted file mode 100644
index 628ea2ab9fe6..000000000000
--- a/lib/Target/PowerPC/PPCMachineBasicBlockUtils.h
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-//==-- PPCMachineBasicBlockUtils.h - Functions for common MBB operations ---==//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file defines utility functions for commonly used operations on
-// MachineBasicBlock's.
-// NOTE: Include this file after defining DEBUG_TYPE so that the debug messages
-// can be emitted for the pass that is using this.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_LIB_TARGET_PPC_MACHINE_BASIC_BLOCK_UTILS_H
-#define LLVM_LIB_TARGET_PPC_MACHINE_BASIC_BLOCK_UTILS_H
-
-#include "PPCInstrInfo.h"
-#include "llvm/CodeGen/MachineInstrBuilder.h"
-#include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
-#include "llvm/CodeGen/MachineRegisterInfo.h"
-
-#ifndef DEBUG_TYPE
-#define DEBUG_TYPE "ppc-generic-mbb-utilities"
-#endif
-
-using namespace llvm;
-
-/// Given a basic block \p Successor that potentially contains PHIs, this
-/// function will look for any incoming values in the PHIs that are supposed to
-/// be coming from \p OrigMBB but whose definition is actually in \p NewMBB.
-/// Any such PHIs will be updated to reflect reality.
-static void updatePHIs(MachineBasicBlock *Successor, MachineBasicBlock *OrigMBB,
- MachineBasicBlock *NewMBB, MachineRegisterInfo *MRI) {
- for (auto &MI : Successor->instrs()) {
- if (!MI.isPHI())
- continue;
- // This is a really ugly-looking loop, but it was pillaged directly from
- // MachineBasicBlock::transferSuccessorsAndUpdatePHIs().
- for (unsigned i = 2, e = MI.getNumOperands()+1; i != e; i += 2) {
- MachineOperand &MO = MI.getOperand(i);
- if (MO.getMBB() == OrigMBB) {
- // Check if the instruction is actualy defined in NewMBB.
- if (MI.getOperand(i-1).isReg()) {
- MachineInstr *DefMI = MRI->getVRegDef(MI.getOperand(i-1).getReg());
- if (DefMI->getParent() == NewMBB || !OrigMBB->isSuccessor(Successor)) {
- MO.setMBB(NewMBB);
- break;
- }
- }
- }
- }
- }
-}
-
-/// Given a basic block \p Successor that potentially contains PHIs, this
-/// function will look for PHIs that have an incoming value from \p OrigMBB
-/// and will add the same incoming value from \p NewMBB.
-/// NOTE: This should only be used if \p NewMBB is an immediate dominator of
-/// \p OrigMBB.
-static void addIncomingValuesToPHIs(MachineBasicBlock *Successor,
- MachineBasicBlock *OrigMBB,
- MachineBasicBlock *NewMBB,
- MachineRegisterInfo *MRI) {
- assert(OrigMBB->isSuccessor(NewMBB) && "NewMBB must be a sucessor of OrigMBB");
- for (auto &MI : Successor->instrs()) {
- if (!MI.isPHI())
- continue;
- // This is a really ugly-looking loop, but it was pillaged directly from
- // MachineBasicBlock::transferSuccessorsAndUpdatePHIs().
- for (unsigned i = 2, e = MI.getNumOperands()+1; i != e; i += 2) {
- MachineOperand &MO = MI.getOperand(i);
- if (MO.getMBB() == OrigMBB) {
- MachineInstrBuilder MIB(*MI.getParent()->getParent(), &MI);
- MIB.addReg(MI.getOperand(i-1).getReg()).addMBB(NewMBB);
- break;
- }
- }
- }
-}
-
-struct BlockSplitInfo {
- MachineInstr *OrigBranch;
- MachineInstr *SplitBefore;
- MachineInstr *SplitCond;
- bool InvertNewBranch;
- bool InvertOrigBranch;
- bool BranchToFallThrough;
- const MachineBranchProbabilityInfo *MBPI;
- MachineInstr *MIToDelete;
- MachineInstr *NewCond;
- bool allInstrsInSameMBB() {
- if (!OrigBranch || !SplitBefore || !SplitCond)
- return false;
- MachineBasicBlock *MBB = OrigBranch->getParent();
- if (SplitBefore->getParent() != MBB ||
- SplitCond->getParent() != MBB)
- return false;
- if (MIToDelete && MIToDelete->getParent() != MBB)
- return false;
- if (NewCond && NewCond->getParent() != MBB)
- return false;
- return true;
- }
-};
-
-/// Splits a MachineBasicBlock to branch before \p SplitBefore. The original
-/// branch is \p OrigBranch. The target of the new branch can either be the same
-/// as the target of the original branch or the fallthrough successor of the
-/// original block as determined by \p BranchToFallThrough. The branch
-/// conditions will be inverted according to \p InvertNewBranch and
-/// \p InvertOrigBranch. If an instruction that previously fed the branch is to
-/// be deleted, it is provided in \p MIToDelete and \p NewCond will be used as
-/// the branch condition. The branch probabilities will be set if the
-/// MachineBranchProbabilityInfo isn't null.
-static bool splitMBB(BlockSplitInfo &BSI) {
- assert(BSI.allInstrsInSameMBB() &&
- "All instructions must be in the same block.");
-
- MachineBasicBlock *ThisMBB = BSI.OrigBranch->getParent();
- MachineFunction *MF = ThisMBB->getParent();
- MachineRegisterInfo *MRI = &MF->getRegInfo();
- assert(MRI->isSSA() && "Can only do this while the function is in SSA form.");
- if (ThisMBB->succ_size() != 2) {
- DEBUG(dbgs() << "Don't know how to handle blocks that don't have exactly"
- << " two succesors.\n");
- return false;
- }
-
- const PPCInstrInfo *TII = MF->getSubtarget<PPCSubtarget>().getInstrInfo();
- unsigned OrigBROpcode = BSI.OrigBranch->getOpcode();
- unsigned InvertedOpcode =
- OrigBROpcode == PPC::BC ? PPC::BCn :
- OrigBROpcode == PPC::BCn ? PPC::BC :
- OrigBROpcode == PPC::BCLR ? PPC::BCLRn : PPC::BCLR;
- unsigned NewBROpcode = BSI.InvertNewBranch ? InvertedOpcode : OrigBROpcode;
- MachineBasicBlock *OrigTarget = BSI.OrigBranch->getOperand(1).getMBB();
- MachineBasicBlock *OrigFallThrough =
- OrigTarget == *ThisMBB->succ_begin() ? *ThisMBB->succ_rbegin() :
- *ThisMBB->succ_begin();
- MachineBasicBlock *NewBRTarget =
- BSI.BranchToFallThrough ? OrigFallThrough : OrigTarget;
- BranchProbability ProbToNewTarget =
- !BSI.MBPI ? BranchProbability::getUnknown() :
- BSI.MBPI->getEdgeProbability(ThisMBB, NewBRTarget);
-
- // Create a new basic block.
- MachineBasicBlock::iterator InsertPoint = BSI.SplitBefore;
- const BasicBlock *LLVM_BB = ThisMBB->getBasicBlock();
- MachineFunction::iterator It = ThisMBB->getIterator();
- MachineBasicBlock *NewMBB = MF->CreateMachineBasicBlock(LLVM_BB);
- MF->insert(++It, NewMBB);
-
- // Move everything after SplitBefore into the new block.
- NewMBB->splice(NewMBB->end(), ThisMBB, InsertPoint, ThisMBB->end());
- NewMBB->transferSuccessors(ThisMBB);
-
- // Add the two successors to ThisMBB. The probabilities come from the
- // existing blocks if available.
- ThisMBB->addSuccessor(NewBRTarget, ProbToNewTarget);
- ThisMBB->addSuccessor(NewMBB, ProbToNewTarget.getCompl());
-
- // Add the branches to ThisMBB.
- BuildMI(*ThisMBB, ThisMBB->end(), BSI.SplitBefore->getDebugLoc(),
- TII->get(NewBROpcode)).addReg(BSI.SplitCond->getOperand(0).getReg())
- .addMBB(NewBRTarget);
- BuildMI(*ThisMBB, ThisMBB->end(), BSI.SplitBefore->getDebugLoc(),
- TII->get(PPC::B)).addMBB(NewMBB);
- if (BSI.MIToDelete)
- BSI.MIToDelete->eraseFromParent();
-
- // Change the condition on the original branch and invert it if requested.
- auto FirstTerminator = NewMBB->getFirstTerminator();
- if (BSI.NewCond) {
- assert(FirstTerminator->getOperand(0).isReg() &&
- "Can't update condition of unconditional branch.");
- FirstTerminator->getOperand(0).setReg(BSI.NewCond->getOperand(0).getReg());
- }
- if (BSI.InvertOrigBranch)
- FirstTerminator->setDesc(TII->get(InvertedOpcode));
-
- // If any of the PHIs in the successors of NewMBB reference values that
- // now come from NewMBB, they need to be updated.
- for (auto *Succ : NewMBB->successors()) {
- updatePHIs(Succ, ThisMBB, NewMBB, MRI);
- }
- addIncomingValuesToPHIs(NewBRTarget, ThisMBB, NewMBB, MRI);
-
- DEBUG(dbgs() << "After splitting, ThisMBB:\n"; ThisMBB->dump());
- DEBUG(dbgs() << "NewMBB:\n"; NewMBB->dump());
- DEBUG(dbgs() << "New branch-to block:\n"; NewBRTarget->dump());
- return true;
-}
-
-
-#endif
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