Initial checkin of codegen infrastructure for LLVM-JIT


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4282 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MFunction.cpp b/lib/CodeGen/MFunction.cpp
new file mode 100644
index 0000000..f586f4c
--- /dev/null
+++ b/lib/CodeGen/MFunction.cpp
@@ -0,0 +1,76 @@
+//===-- MFunction.cpp - Implementation code for the MFunction class -------===//
+//
+// This file contains a printer that converts from our internal representation
+// of LLVM code to a nice human readable form that is suitable for debuggging.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/MFunction.h"
+#include "llvm/Target/MInstructionInfo.h"
+#include "llvm/Target/MRegisterInfo.h"
+#include <iostream>
+
+static void printMRegister(unsigned RegNo, const MRegisterInfo &MRI,
+                           std::ostream &OS) {
+  if (RegNo < MRegisterInfo::FirstVirtualRegister) {
+    OS << "%" << MRI[RegNo].Name;  // Hard registers are prefixed with %
+  } else {
+    OS << "reg" << RegNo;  // SSA registers are printed with 'reg' prefix
+  }
+}
+
+static void printMInstruction(const MInstruction &MI, std::ostream &OS,
+                              const MInstructionInfo &MII) {
+  const MRegisterInfo &MRI = MII.getRegisterInfo();
+  OS << "\t";
+  if (MI.getDestinationReg() != MRegisterInfo::NoRegister) {// Produces a value?
+    printMRegister(MI.getDestinationReg(), MRI, OS);
+    OS << " = ";
+  }
+
+  OS << MII[MI.getOpcode()].Name << " ";
+
+  for (unsigned i = 0, e = MI.getNumOperands(); i != e; ++i) {
+    if (i != 0) OS << ", ";
+    switch (MI.getOperandInterpretation(i)) {
+    case MOperand::Register:
+      printMRegister(MI.getRegisterOperand(i), MRI, OS);
+      break;
+    case MOperand::SignExtImmediate:
+      OS << MI.getSignExtOperand(i) << "s";
+      break;
+    case MOperand::ZeroExtImmediate:
+      OS << MI.getZeroExtOperand(i) << "z";
+      break;
+    case MOperand::PCRelativeDisp:
+      if (MI.getPCRelativeOperand(i) >= 0)
+        OS << "pc+" << MI.getPCRelativeOperand(i);
+      else
+        OS << "pc" << MI.getPCRelativeOperand(i);
+      break;
+    default:
+      OS << "*UNKNOWN OPERAND INTERPRETATION*";
+      break;
+    }
+  }
+  OS << "\n";
+}
+
+/// print - Provide a way to get a simple debugging dump.  This dumps the
+/// machine code in a simple "assembly" language that is not really suitable
+/// for an assembler, but is useful for debugging.  This is completely target
+/// independant.
+///
+void MFunction::print(std::ostream &OS, const MInstructionInfo &MII) const {
+  for (const_iterator I = begin(), E = end(); I != E; ++I) {
+    for (MBasicBlock::const_iterator II = I->begin(), IE = I->end();
+         II != IE; ++II)
+      printMInstruction(*II, OS, MII);
+    OS << "\n";  // blank line between basic blocks...
+  }
+}
+
+void MFunction::dump(const MInstructionInfo &MII) const {
+  print(std::cerr, MII);
+}
+