Initial checkin of MachineInstrBuilder class

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4360 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/CodeGen/MachineInstrBuilder.h

@@ -0,0 +1,81 @@
+//===-- CodeGen/MachineInstBuilder.h - Simplify creation of MIs -*- C++ -*-===//
+//
+// This file exposes a function named BuildMI, which is useful for dramatically
+// simplifying how MachineInstr's are created.  Instead of using code like this:
+//
+//   M = new MachineInstr(X86::ADDrr32);
+//   M->SetMachineOperandVal(0, MachineOperand::MO_VirtualRegister, argVal1);
+//   M->SetMachineOperandVal(1, MachineOperand::MO_VirtualRegister, argVal2);
+//
+// we can now use code like this:
+//
+//   M = BuildMI(X86::ADDrr8).addReg(argVal1).addReg(argVal2);
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_MACHINEINSTRBUILDER_H
+#define LLVM_CODEGEN_MACHINEINSTRBUILDER_H
+
+#include "llvm/CodeGen/MachineInstr.h"
+
+struct MachineInstrBuilder { 
+  MachineInstr *MI;
+
+  MachineInstrBuilder(MachineInstr *mi) : MI(mi) {}
+
+  /// Allow automatic conversion to the machine instruction we are working on.
+  ///
+  operator MachineInstr*() const { return MI; }
+
+  /// addReg - Add a new register operand...
+  ///
+  MachineInstrBuilder &addReg(int RegNo) {
+    MI->addRegOperand(RegNo);
+    return *this;
+  }
+
+  MachineInstrBuilder &addReg(Value *V, bool isDef = false, bool isDNU = false){
+    MI->addRegOperand(V, isDef, isDNU);
+    return *this;
+  }
+
+  MachineInstrBuilder &addPCDisp(Value *V) {
+    MI->addPCDispOperand(V);
+    return *this;
+  }
+
+  MachineInstrBuilder &addMReg(int Reg, bool isDef=false) {
+    MI->addMachineRegOperand(Reg, isDef);
+    return *this;
+  }
+
+  /// addSImm - Add a new sign extended immediate operand...
+  ///
+  MachineInstrBuilder &addSImm(int64_t val) {
+    MI->addSignExtImmOperand(val);
+    return *this;
+  }
+
+  /// addZImm - Add a new zero extended immediate operand...
+  ///
+  MachineInstrBuilder &addZImm(int64_t Val) {
+    MI->addZeroExtImmOperand(Val);
+    return *this;
+  }
+};
+
+/// BuildMI - Builder interface.  Specify how to create the initial instruction
+/// itself.
+///
+inline MachineInstrBuilder BuildMI(MachineOpCode Opcode, unsigned NumOperands) {
+  return MachineInstrBuilder(new MachineInstr(Opcode, NumOperands, true, true));
+}
+
+#if 0
+inline MachineInstrBuilder BuildMI(MBasicBlock *BB, MachineOpCode Opcode,
+                                   unsigned DestReg = 0) {
+  return MachineInstrBuilder(new MachineInstr(BB, Opcode, DestReg));
+}
+#endif
+                                
+#endif