It's not necessary to do rounding for alloca operations when the requested

alignment is equal to the stack alignment.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40004 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 303 insertions, 0 deletions

diff --git a/lib/Target/PowerPC/PPCInstrInfo.cpp b/lib/Target/PowerPC/PPCInstrInfo.cpp
new file mode 100644
index 0000000..d7ee5ed
--- /dev/null
+++ b/lib/Target/PowerPC/PPCInstrInfo.cpp
@@ -0,0 +1,303 @@
+//===- PPCInstrInfo.cpp - PowerPC32 Instruction Information -----*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the PowerPC implementation of the TargetInstrInfo class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "PPCInstrInfo.h"
+#include "PPCPredicates.h"
+#include "PPCGenInstrInfo.inc"
+#include "PPCTargetMachine.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+using namespace llvm;
+
+PPCInstrInfo::PPCInstrInfo(PPCTargetMachine &tm)
+  : TargetInstrInfo(PPCInsts, sizeof(PPCInsts)/sizeof(PPCInsts[0])), TM(tm),
+    RI(*TM.getSubtargetImpl(), *this) {}
+
+/// getPointerRegClass - Return the register class to use to hold pointers.
+/// This is used for addressing modes.
+const TargetRegisterClass *PPCInstrInfo::getPointerRegClass() const {
+  if (TM.getSubtargetImpl()->isPPC64())
+    return &PPC::G8RCRegClass;
+  else
+    return &PPC::GPRCRegClass;
+}
+
+
+bool PPCInstrInfo::isMoveInstr(const MachineInstr& MI,
+                               unsigned& sourceReg,
+                               unsigned& destReg) const {
+  MachineOpCode oc = MI.getOpcode();
+  if (oc == PPC::OR || oc == PPC::OR8 || oc == PPC::VOR ||
+      oc == PPC::OR4To8 || oc == PPC::OR8To4) {                // or r1, r2, r2
+    assert(MI.getNumOperands() >= 3 &&
+           MI.getOperand(0).isRegister() &&
+           MI.getOperand(1).isRegister() &&
+           MI.getOperand(2).isRegister() &&
+           "invalid PPC OR instruction!");
+    if (MI.getOperand(1).getReg() == MI.getOperand(2).getReg()) {
+      sourceReg = MI.getOperand(1).getReg();
+      destReg = MI.getOperand(0).getReg();
+      return true;
+    }
+  } else if (oc == PPC::ADDI) {             // addi r1, r2, 0
+    assert(MI.getNumOperands() >= 3 &&
+           MI.getOperand(0).isRegister() &&
+           MI.getOperand(2).isImmediate() &&
+           "invalid PPC ADDI instruction!");
+    if (MI.getOperand(1).isRegister() && MI.getOperand(2).getImmedValue()==0) {
+      sourceReg = MI.getOperand(1).getReg();
+      destReg = MI.getOperand(0).getReg();
+      return true;
+    }
+  } else if (oc == PPC::ORI) {             // ori r1, r2, 0
+    assert(MI.getNumOperands() >= 3 &&
+           MI.getOperand(0).isRegister() &&
+           MI.getOperand(1).isRegister() &&
+           MI.getOperand(2).isImmediate() &&
+           "invalid PPC ORI instruction!");
+    if (MI.getOperand(2).getImmedValue()==0) {
+      sourceReg = MI.getOperand(1).getReg();
+      destReg = MI.getOperand(0).getReg();
+      return true;
+    }
+  } else if (oc == PPC::FMRS || oc == PPC::FMRD ||
+             oc == PPC::FMRSD) {      // fmr r1, r2
+    assert(MI.getNumOperands() >= 2 &&
+           MI.getOperand(0).isRegister() &&
+           MI.getOperand(1).isRegister() &&
+           "invalid PPC FMR instruction");
+    sourceReg = MI.getOperand(1).getReg();
+    destReg = MI.getOperand(0).getReg();
+    return true;
+  } else if (oc == PPC::MCRF) {             // mcrf cr1, cr2
+    assert(MI.getNumOperands() >= 2 &&
+           MI.getOperand(0).isRegister() &&
+           MI.getOperand(1).isRegister() &&
+           "invalid PPC MCRF instruction");
+    sourceReg = MI.getOperand(1).getReg();
+    destReg = MI.getOperand(0).getReg();
+    return true;
+  }
+  return false;
+}
+
+unsigned PPCInstrInfo::isLoadFromStackSlot(MachineInstr *MI, 
+                                           int &FrameIndex) const {
+  switch (MI->getOpcode()) {
+  default: break;
+  case PPC::LD:
+  case PPC::LWZ:
+  case PPC::LFS:
+  case PPC::LFD:
+    if (MI->getOperand(1).isImmediate() && !MI->getOperand(1).getImmedValue() &&
+        MI->getOperand(2).isFrameIndex()) {
+      FrameIndex = MI->getOperand(2).getFrameIndex();
+      return MI->getOperand(0).getReg();
+    }
+    break;
+  }
+  return 0;
+}
+
+unsigned PPCInstrInfo::isStoreToStackSlot(MachineInstr *MI, 
+                                          int &FrameIndex) const {
+  switch (MI->getOpcode()) {
+  default: break;
+  case PPC::STD:
+  case PPC::STW:
+  case PPC::STFS:
+  case PPC::STFD:
+    if (MI->getOperand(1).isImmediate() && !MI->getOperand(1).getImmedValue() &&
+        MI->getOperand(2).isFrameIndex()) {
+      FrameIndex = MI->getOperand(2).getFrameIndex();
+      return MI->getOperand(0).getReg();
+    }
+    break;
+  }
+  return 0;
+}
+
+// commuteInstruction - We can commute rlwimi instructions, but only if the
+// rotate amt is zero.  We also have to munge the immediates a bit.
+MachineInstr *PPCInstrInfo::commuteInstruction(MachineInstr *MI) const {
+  // Normal instructions can be commuted the obvious way.
+  if (MI->getOpcode() != PPC::RLWIMI)
+    return TargetInstrInfo::commuteInstruction(MI);
+  
+  // Cannot commute if it has a non-zero rotate count.
+  if (MI->getOperand(3).getImmedValue() != 0)
+    return 0;
+  
+  // If we have a zero rotate count, we have:
+  //   M = mask(MB,ME)
+  //   Op0 = (Op1 & ~M) | (Op2 & M)
+  // Change this to:
+  //   M = mask((ME+1)&31, (MB-1)&31)
+  //   Op0 = (Op2 & ~M) | (Op1 & M)
+
+  // Swap op1/op2
+  unsigned Reg1 = MI->getOperand(1).getReg();
+  unsigned Reg2 = MI->getOperand(2).getReg();
+  bool Reg1IsKill = MI->getOperand(1).isKill();
+  bool Reg2IsKill = MI->getOperand(2).isKill();
+  MI->getOperand(2).setReg(Reg1);
+  MI->getOperand(1).setReg(Reg2);
+  if (Reg1IsKill)
+    MI->getOperand(2).setIsKill();
+  else
+    MI->getOperand(2).unsetIsKill();
+  if (Reg2IsKill)
+    MI->getOperand(1).setIsKill();
+  else
+    MI->getOperand(1).unsetIsKill();
+  
+  // Swap the mask around.
+  unsigned MB = MI->getOperand(4).getImmedValue();
+  unsigned ME = MI->getOperand(5).getImmedValue();
+  MI->getOperand(4).setImmedValue((ME+1) & 31);
+  MI->getOperand(5).setImmedValue((MB-1) & 31);
+  return MI;
+}
+
+void PPCInstrInfo::insertNoop(MachineBasicBlock &MBB, 
+                              MachineBasicBlock::iterator MI) const {
+  BuildMI(MBB, MI, get(PPC::NOP));
+}
+
+
+// Branch analysis.
+bool PPCInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,MachineBasicBlock *&TBB,
+                                 MachineBasicBlock *&FBB,
+                                 std::vector<MachineOperand> &Cond) const {
+  // If the block has no terminators, it just falls into the block after it.
+  MachineBasicBlock::iterator I = MBB.end();
+  if (I == MBB.begin() || !isUnpredicatedTerminator(--I))
+    return false;
+
+  // Get the last instruction in the block.
+  MachineInstr *LastInst = I;
+  
+  // If there is only one terminator instruction, process it.
+  if (I == MBB.begin() || !isUnpredicatedTerminator(--I)) {
+    if (LastInst->getOpcode() == PPC::B) {
+      TBB = LastInst->getOperand(0).getMachineBasicBlock();
+      return false;
+    } else if (LastInst->getOpcode() == PPC::BCC) {
+      // Block ends with fall-through condbranch.
+      TBB = LastInst->getOperand(2).getMachineBasicBlock();
+      Cond.push_back(LastInst->getOperand(0));
+      Cond.push_back(LastInst->getOperand(1));
+      return false;
+    }
+    // Otherwise, don't know what this is.
+    return true;
+  }
+  
+  // Get the instruction before it if it's a terminator.
+  MachineInstr *SecondLastInst = I;
+
+  // If there are three terminators, we don't know what sort of block this is.
+  if (SecondLastInst && I != MBB.begin() &&
+      isUnpredicatedTerminator(--I))
+    return true;
+  
+  // If the block ends with PPC::B and PPC:BCC, handle it.
+  if (SecondLastInst->getOpcode() == PPC::BCC && 
+      LastInst->getOpcode() == PPC::B) {
+    TBB =  SecondLastInst->getOperand(2).getMachineBasicBlock();
+    Cond.push_back(SecondLastInst->getOperand(0));
+    Cond.push_back(SecondLastInst->getOperand(1));
+    FBB = LastInst->getOperand(0).getMachineBasicBlock();
+    return false;
+  }
+  
+  // If the block ends with two PPC:Bs, handle it.  The second one is not
+  // executed, so remove it.
+  if (SecondLastInst->getOpcode() == PPC::B && 
+      LastInst->getOpcode() == PPC::B) {
+    TBB = SecondLastInst->getOperand(0).getMachineBasicBlock();
+    I = LastInst;
+    I->eraseFromParent();
+    return false;
+  }
+
+  // Otherwise, can't handle this.
+  return true;
+}
+
+unsigned PPCInstrInfo::RemoveBranch(MachineBasicBlock &MBB) const {
+  MachineBasicBlock::iterator I = MBB.end();
+  if (I == MBB.begin()) return 0;
+  --I;
+  if (I->getOpcode() != PPC::B && I->getOpcode() != PPC::BCC)
+    return 0;
+  
+  // Remove the branch.
+  I->eraseFromParent();
+  
+  I = MBB.end();
+
+  if (I == MBB.begin()) return 1;
+  --I;
+  if (I->getOpcode() != PPC::BCC)
+    return 1;
+  
+  // Remove the branch.
+  I->eraseFromParent();
+  return 2;
+}
+
+unsigned
+PPCInstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
+                           MachineBasicBlock *FBB,
+                           const std::vector<MachineOperand> &Cond) const {
+  // Shouldn't be a fall through.
+  assert(TBB && "InsertBranch must not be told to insert a fallthrough");
+  assert((Cond.size() == 2 || Cond.size() == 0) && 
+         "PPC branch conditions have two components!");
+  
+  // One-way branch.
+  if (FBB == 0) {
+    if (Cond.empty())   // Unconditional branch
+      BuildMI(&MBB, get(PPC::B)).addMBB(TBB);
+    else                // Conditional branch
+      BuildMI(&MBB, get(PPC::BCC))
+        .addImm(Cond[0].getImm()).addReg(Cond[1].getReg()).addMBB(TBB);
+    return 1;
+  }
+  
+  // Two-way Conditional Branch.
+  BuildMI(&MBB, get(PPC::BCC))
+    .addImm(Cond[0].getImm()).addReg(Cond[1].getReg()).addMBB(TBB);
+  BuildMI(&MBB, get(PPC::B)).addMBB(FBB);
+  return 2;
+}
+
+bool PPCInstrInfo::BlockHasNoFallThrough(MachineBasicBlock &MBB) const {
+  if (MBB.empty()) return false;
+  
+  switch (MBB.back().getOpcode()) {
+  case PPC::BLR:   // Return.
+  case PPC::B:     // Uncond branch.
+  case PPC::BCTR:  // Indirect branch.
+    return true;
+  default: return false;
+  }
+}
+
+bool PPCInstrInfo::
+ReverseBranchCondition(std::vector<MachineOperand> &Cond) const {
+  assert(Cond.size() == 2 && "Invalid PPC branch opcode!");
+  // Leave the CR# the same, but invert the condition.
+  Cond[0].setImm(PPC::InvertPredicate((PPC::Predicate)Cond[0].getImm()));
+  return false;
+}