done

[oota-llvm.git] / lib / Target / X86 / X86InstrBuilder.h

diff --git a/lib/Target/X86/X86InstrBuilder.h b/lib/Target/X86/X86InstrBuilder.h
index 1d9d6b9e1a7f9e38f297c8340b144d4d95b58f20..c0fa58debffc3952ae692bab45ac25d3a188e4a7 100644 (file)
--- a/lib/Target/X86/X86InstrBuilder.h
+++ b/lib/Target/X86/X86InstrBuilder.h
@@ -1,5 +1,12 @@
 //===-- X86InstrBuilder.h - Functions to aid building x86 insts -*- 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 exposes functions that may be used with BuildMI from the
 // MachineInstrBuilder.h file to handle X86'isms in a clean way.
 //
@@ -9,6 +16,9 @@
 // up behind an easier to use interface makes sense.  Descriptions of the
 // functions are included below.
 //
+// For reference, the order of operands for memory references is:
+// (Operand), Base, Scale, Index, Displacement.
+//
 //===----------------------------------------------------------------------===//
 
 #ifndef X86INSTRBUILDER_H
@@ -16,13 +26,100 @@
 
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 
+namespace llvm {
+
+/// X86AddressMode - This struct holds a generalized full x86 address mode.
+/// The base register can be a frame index, which will eventually be replaced
+/// with BP or SP and Disp being offsetted accordingly.  The displacement may
+/// also include the offset of a global value.
+struct X86AddressMode {
+  enum {
+    RegBase,
+    FrameIndexBase
+  } BaseType;
+
+  union {
+    unsigned Reg;
+    int FrameIndex;
+  } Base;
+
+  unsigned Scale;
+  unsigned IndexReg;
+  unsigned Disp;
+  GlobalValue *GV;
+
+  X86AddressMode() : BaseType(RegBase), Scale(1), IndexReg(0), Disp(0), GV(0) {
+    Base.Reg = 0;
+  }
+};
+
 /// addDirectMem - This function is used to add a direct memory reference to the
-/// current instruction.  Because memory references are always represented with
-/// four values, this adds: Reg, [1, NoReg, 0] to the instruction
+/// current instruction -- that is, a dereference of an address in a register,
+/// with no scale, index or displacement. An example is: DWORD PTR [EAX].
 ///
 inline const MachineInstrBuilder &addDirectMem(const MachineInstrBuilder &MIB,
                                                unsigned Reg) {
-  return MIB.addReg(Reg).addZImm(1).addMReg(0).addSImm(0);
+  // Because memory references are always represented with four
+  // values, this adds: Reg, [1, NoReg, 0] to the instruction.
+  return MIB.addReg(Reg).addImm(1).addReg(0).addImm(0);
+}
+
+
+/// addRegOffset - This function is used to add a memory reference of the form
+/// [Reg + Offset], i.e., one with no scale or index, but with a
+/// displacement. An example is: DWORD PTR [EAX + 4].
+///
+inline const MachineInstrBuilder &addRegOffset(const MachineInstrBuilder &MIB,
+                                               unsigned Reg, int Offset) {
+  return MIB.addReg(Reg).addImm(1).addReg(0).addImm(Offset);
+}
+
+/// addRegReg - This function is used to add a memory reference of the form:
+/// [Reg + Reg].
+inline const MachineInstrBuilder &addRegReg(const MachineInstrBuilder &MIB,
+                                            unsigned Reg1, unsigned Reg2) {
+  return MIB.addReg(Reg1).addImm(1).addReg(Reg2).addImm(0);
 }
 
+inline const MachineInstrBuilder &addFullAddress(const MachineInstrBuilder &MIB,
+                                                 const X86AddressMode &AM) {
+  assert (AM.Scale == 1 || AM.Scale == 2 || AM.Scale == 4 || AM.Scale == 8);
+
+  if (AM.BaseType == X86AddressMode::RegBase)
+    MIB.addReg(AM.Base.Reg);
+  else if (AM.BaseType == X86AddressMode::FrameIndexBase)
+    MIB.addFrameIndex(AM.Base.FrameIndex);
+  else
+    assert (0);
+  MIB.addImm(AM.Scale).addReg(AM.IndexReg);
+  if (AM.GV)
+    return MIB.addGlobalAddress(AM.GV, AM.Disp);
+  else
+    return MIB.addImm(AM.Disp);
+}
+
+/// addFrameReference - This function is used to add a reference to the base of
+/// an abstract object on the stack frame of the current function.  This
+/// reference has base register as the FrameIndex offset until it is resolved.
+/// This allows a constant offset to be specified as well...
+///
+inline const MachineInstrBuilder &
+addFrameReference(const MachineInstrBuilder &MIB, int FI, int Offset = 0) {
+  return MIB.addFrameIndex(FI).addImm(1).addReg(0).addImm(Offset);
+}
+
+/// addConstantPoolReference - This function is used to add a reference to the
+/// base of a constant value spilled to the per-function constant pool.  The
+/// reference has base register ConstantPoolIndex offset which is retained until
+/// either machine code emission or assembly output.  This allows an optional
+/// offset to be added as well.
+///
+inline const MachineInstrBuilder &
+addConstantPoolReference(const MachineInstrBuilder &MIB, unsigned CPI,
+                         int Offset = 0) {
+  return MIB.addConstantPoolIndex(CPI).addImm(1).addReg(0).addImm(Offset);
+}
+
+} // End llvm namespace
+
 #endif