Change MachineBasicBlock's vector of MachineInstr pointers into an

ilist of MachineInstr objects. This allows constant time removal and
insertion of MachineInstr instances from anywhere in each
MachineBasicBlock. It also allows for constant time splicing of
MachineInstrs into or out of MachineBasicBlocks.

llvm-svn: 11340

1 files changed, 10 insertions, 11 deletions

diff --git a/llvm/lib/CodeGen/RegAllocLinearScan.cpp b/llvm/lib/CodeGen/RegAllocLinearScan.cpp
index 9df824abc31..b9d6f0846fe 100644
--- a/llvm/lib/CodeGen/RegAllocLinearScan.cpp
+++ b/llvm/lib/CodeGen/RegAllocLinearScan.cpp
@@ -396,15 +396,15 @@ bool RA::runOnMachineFunction(MachineFunction &fn) {
         for (currentInstr_ = currentMbb_->begin();
              currentInstr_ != currentMbb_->end(); ) {
             DEBUG(std::cerr << "\tinstruction: ";
-                  (*currentInstr_)->print(std::cerr, *tm_););
+                  currentInstr_->print(std::cerr, *tm_););
 
             // use our current mapping and actually replace and
             // virtual register with its allocated physical registers
             DEBUG(std::cerr << "\t\treplacing virtual registers with mapped "
                   "physical registers:\n");
-            for (unsigned i = 0, e = (*currentInstr_)->getNumOperands();
+            for (unsigned i = 0, e = currentInstr_->getNumOperands();
                  i != e; ++i) {
-                MachineOperand& op = (*currentInstr_)->getOperand(i);
+                MachineOperand& op = currentInstr_->getOperand(i);
                 if (op.isRegister() &&
                     MRegisterInfo::isVirtualRegister(op.getReg())) {
                     unsigned virtReg = op.getReg();
@@ -412,20 +412,19 @@ bool RA::runOnMachineFunction(MachineFunction &fn) {
                     if (it != v2pMap_.end()) {
                         DEBUG(std::cerr << "\t\t\t%reg" << it->first
                               << " -> " << mri_->getName(it->second) << '\n');
-                        (*currentInstr_)->SetMachineOperandReg(i, it->second);
+                        currentInstr_->SetMachineOperandReg(i, it->second);
                     }
                 }
             }
 
             unsigned srcReg, dstReg;
-            if (tii.isMoveInstr(**currentInstr_, srcReg, dstReg) &&
+            if (tii.isMoveInstr(*currentInstr_, srcReg, dstReg) &&
                 ((MRegisterInfo::isPhysicalRegister(srcReg) &&
                   MRegisterInfo::isPhysicalRegister(dstReg) &&
                   srcReg == dstReg) ||
                  (MRegisterInfo::isVirtualRegister(srcReg) &&
                   MRegisterInfo::isVirtualRegister(dstReg) &&
                   v2ssMap_[srcReg] == v2ssMap_[dstReg]))) {
-                delete *currentInstr_;
                 currentInstr_ = currentMbb_->erase(currentInstr_);
                 ++numPeep;
                 DEBUG(std::cerr << "\t\tdeleting instruction\n");
@@ -436,12 +435,12 @@ bool RA::runOnMachineFunction(MachineFunction &fn) {
             Regs toClear;
             Regs toSpill;
 
-            const unsigned numOperands = (*currentInstr_)->getNumOperands();
+            const unsigned numOperands = currentInstr_->getNumOperands();
 
             DEBUG(std::cerr << "\t\tloading temporarily used operands to "
                   "registers:\n");
             for (unsigned i = 0; i != numOperands; ++i) {
-                MachineOperand& op = (*currentInstr_)->getOperand(i);
+                MachineOperand& op = currentInstr_->getOperand(i);
                 if (op.isRegister() && op.isUse() &&
                     MRegisterInfo::isVirtualRegister(op.getReg())) {
                     unsigned virtReg = op.getAllocatedRegNum();
@@ -460,7 +459,7 @@ bool RA::runOnMachineFunction(MachineFunction &fn) {
                         else
                             toClear.push_back(it);
                     }
-                    (*currentInstr_)->SetMachineOperandReg(i, physReg);
+                    currentInstr_->SetMachineOperandReg(i, physReg);
                 }
             }
 
@@ -472,7 +471,7 @@ bool RA::runOnMachineFunction(MachineFunction &fn) {
             DEBUG(std::cerr << "\t\tassigning temporarily defined operands to "
                   "registers:\n");
             for (unsigned i = 0; i != numOperands; ++i) {
-                MachineOperand& op = (*currentInstr_)->getOperand(i);
+                MachineOperand& op = currentInstr_->getOperand(i);
                 if (op.isRegister() &&
                     MRegisterInfo::isVirtualRegister(op.getReg())) {
                     assert(!op.isUse() && "we should not have uses here!");
@@ -489,7 +488,7 @@ bool RA::runOnMachineFunction(MachineFunction &fn) {
                         // this instruction
                         toSpill.push_back(it);
                     }
-                    (*currentInstr_)->SetMachineOperandReg(i, physReg);
+                    currentInstr_->SetMachineOperandReg(i, physReg);
                 }
             }
             ++currentInstr_; // spills will go after this instruction