Remove dead store.

[oota-llvm.git] / lib / CodeGen / MachineInstr.cpp

diff --git a/lib/CodeGen/MachineInstr.cpp b/lib/CodeGen/MachineInstr.cpp
index f73a5a362112f3701820b748b6a9a5164992a995..f919510525f4aa1cfd434953b70a2ebc81e8d067 100644 (file)
--- a/lib/CodeGen/MachineInstr.cpp
+++ b/lib/CodeGen/MachineInstr.cpp
@@ -555,8 +555,13 @@ void MachineInstr::addOperand(const MachineOperand &Op) {
       Operands.back().ParentMI = this;
   
       // If the operand is a register, update the operand's use list.
-      if (Op.isReg())
+      if (Op.isReg()) {
         Operands.back().AddRegOperandToRegInfo(RegInfo);
+        // If the register operand is flagged as early, mark the operand as such
+        unsigned OpNo = Operands.size() - 1;
+        if (TID->getOperandConstraint(OpNo, TOI::EARLY_CLOBBER) != -1)
+          Operands[OpNo].setIsEarlyClobber(true);
+      }
       return;
     }
   }
@@ -573,8 +578,12 @@ void MachineInstr::addOperand(const MachineOperand &Op) {
 
     // Do explicitly set the reginfo for this operand though, to ensure the
     // next/prev fields are properly nulled out.
-    if (Operands[OpNo].isReg())
+    if (Operands[OpNo].isReg()) {
       Operands[OpNo].AddRegOperandToRegInfo(0);
+      // If the register operand is flagged as early, mark the operand as such
+      if (TID->getOperandConstraint(OpNo, TOI::EARLY_CLOBBER) != -1)
+        Operands[OpNo].setIsEarlyClobber(true);
+    }
 
   } else if (Operands.size()+1 <= Operands.capacity()) {
     // Otherwise, we have to remove register operands from their register use
@@ -594,8 +603,12 @@ void MachineInstr::addOperand(const MachineOperand &Op) {
     Operands.insert(Operands.begin()+OpNo, Op);
     Operands[OpNo].ParentMI = this;
 
-    if (Operands[OpNo].isReg())
+    if (Operands[OpNo].isReg()) {
       Operands[OpNo].AddRegOperandToRegInfo(RegInfo);
+      // If the register operand is flagged as early, mark the operand as such
+      if (TID->getOperandConstraint(OpNo, TOI::EARLY_CLOBBER) != -1)
+        Operands[OpNo].setIsEarlyClobber(true);
+    }
     
     // Re-add all the implicit ops.
     for (unsigned i = OpNo+1, e = Operands.size(); i != e; ++i) {
@@ -613,6 +626,11 @@ void MachineInstr::addOperand(const MachineOperand &Op) {
   
     // Re-add all the operands.
     AddRegOperandsToUseLists(*RegInfo);
+
+      // If the register operand is flagged as early, mark the operand as such
+    if (Operands[OpNo].isReg()
+        && TID->getOperandConstraint(OpNo, TOI::EARLY_CLOBBER) != -1)
+      Operands[OpNo].setIsEarlyClobber(true);
   }
 }
 
@@ -1058,6 +1076,22 @@ bool MachineInstr::isInvariantLoad(AliasAnalysis *AA) const {
   return true;
 }
 
+/// isConstantValuePHI - If the specified instruction is a PHI that always
+/// merges together the same virtual register, return the register, otherwise
+/// return 0.
+unsigned MachineInstr::isConstantValuePHI() const {
+  if (getOpcode() != TargetInstrInfo::PHI)
+    return 0;
+  assert(getNumOperands() >= 3 &&
+         "It's illegal to have a PHI without source operands");
+
+  unsigned Reg = getOperand(1).getReg();
+  for (unsigned i = 3, e = getNumOperands(); i < e; i += 2)
+    if (getOperand(i).getReg() != Reg)
+      return 0;
+  return Reg;
+}
+
 void MachineInstr::dump() const {
   errs() << "  " << *this;
 }
@@ -1125,7 +1159,7 @@ void MachineInstr::print(raw_ostream &OS, const TargetMachine *TM) const {
 
   // Briefly indicate whether any call clobbers were omitted.
   if (OmittedAnyCallClobbers) {
-    if (FirstOp) FirstOp = false; else OS << ",";
+    if (!FirstOp) OS << ",";
     OS << " ...";
   }
 
@@ -1143,16 +1177,21 @@ void MachineInstr::print(raw_ostream &OS, const TargetMachine *TM) const {
   }
 
   if (!debugLoc.isUnknown() && MF) {
-    if (!HaveSemi) OS << ";"; HaveSemi = true;
+    if (!HaveSemi) OS << ";";
 
     // TODO: print InlinedAtLoc information
 
     DebugLocTuple DLT = MF->getDebugLocTuple(debugLoc);
     DIScope Scope(DLT.Scope);
     OS << " dbg:";
+    // Omit the directory, since it's usually long and uninteresting.
     if (!Scope.isNull())
-      OS << Scope.getDirectory() << ':' << Scope.getFilename() << ':';
-    OS << DLT.Line << ":" << DLT.Col;
+      OS << Scope.getFilename();
+    else
+      OS << "<unknown>";
+    OS << ':' << DLT.Line;
+    if (DLT.Col != 0)
+      OS << ':' << DLT.Col;
   }
 
   OS << "\n";