Let's start another backend :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75909 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/SystemZ/SystemZISelDAGToDAG.cpp b/lib/Target/SystemZ/SystemZISelDAGToDAG.cpp
new file mode 100644
index 0000000..9b9eeb2
--- /dev/null
+++ b/lib/Target/SystemZ/SystemZISelDAGToDAG.cpp
@@ -0,0 +1,129 @@
+//==-- SystemZISelDAGToDAG.cpp - A dag to dag inst selector for SystemZ ---===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines an instruction selector for the SystemZ target.
+//
+//===----------------------------------------------------------------------===//
+
+#include "SystemZ.h"
+#include "SystemZISelLowering.h"
+#include "SystemZTargetMachine.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Function.h"
+#include "llvm/Intrinsics.h"
+#include "llvm/CallingConv.h"
+#include "llvm/Constants.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/SelectionDAG.h"
+#include "llvm/CodeGen/SelectionDAGISel.h"
+#include "llvm/Target/TargetLowering.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/Debug.h"
+using namespace llvm;
+
+/// SystemZDAGToDAGISel - SystemZ specific code to select SystemZ machine
+/// instructions for SelectionDAG operations.
+///
+namespace {
+ class SystemZDAGToDAGISel : public SelectionDAGISel {
+ SystemZTargetLowering &Lowering;
+ const SystemZSubtarget &Subtarget;
+
+ public:
+ SystemZDAGToDAGISel(SystemZTargetMachine &TM, CodeGenOpt::Level OptLevel)
+ : SelectionDAGISel(TM, OptLevel),
+ Lowering(*TM.getTargetLowering()),
+ Subtarget(*TM.getSubtargetImpl()) { }
+
+ virtual void InstructionSelect();
+
+ virtual const char *getPassName() const {
+ return "SystemZ DAG->DAG Pattern Instruction Selection";
+ }
+
+ // Include the pieces autogenerated from the target description.
+ #include "SystemZGenDAGISel.inc"
+
+ private:
+ SDNode *Select(SDValue Op);
+
+ #ifndef NDEBUG
+ unsigned Indent;
+ #endif
+ };
+} // end anonymous namespace
+
+/// createSystemZISelDag - This pass converts a legalized DAG into a
+/// SystemZ-specific DAG, ready for instruction scheduling.
+///
+FunctionPass *llvm::createSystemZISelDag(SystemZTargetMachine &TM,
+ CodeGenOpt::Level OptLevel) {
+ return new SystemZDAGToDAGISel(TM, OptLevel);
+}
+
+
+/// InstructionSelect - This callback is invoked by
+/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
+void SystemZDAGToDAGISel::InstructionSelect() {
+ DEBUG(BB->dump());
+
+ // Codegen the basic block.
+#ifndef NDEBUG
+ DOUT << "===== Instruction selection begins:\n";
+ Indent = 0;
+#endif
+ SelectRoot(*CurDAG);
+#ifndef NDEBUG
+ DOUT << "===== Instruction selection ends:\n";
+#endif
+
+ CurDAG->RemoveDeadNodes();
+}
+
+SDNode *SystemZDAGToDAGISel::Select(SDValue Op) {
+ SDNode *Node = Op.getNode();
+ DebugLoc dl = Op.getDebugLoc();
+
+ // Dump information about the Node being selected
+ #ifndef NDEBUG
+ DOUT << std::string(Indent, ' ') << "Selecting: ";
+ DEBUG(Node->dump(CurDAG));
+ DOUT << "\n";
+ Indent += 2;
+ #endif
+
+ // If we have a custom node, we already have selected!
+ if (Node->isMachineOpcode()) {
+ #ifndef NDEBUG
+ DOUT << std::string(Indent-2, ' ') << "== ";
+ DEBUG(Node->dump(CurDAG));
+ DOUT << "\n";
+ Indent -= 2;
+ #endif
+ return NULL;
+ }
+
+ // Select the default instruction
+ SDNode *ResNode = SelectCode(Op);
+
+ #ifndef NDEBUG
+ DOUT << std::string(Indent-2, ' ') << "=> ";
+ if (ResNode == NULL || ResNode == Op.getNode())
+ DEBUG(Op.getNode()->dump(CurDAG));
+ else
+ DEBUG(ResNode->dump(CurDAG));
+ DOUT << "\n";
+ Indent -= 2;
+ #endif
+
+ return ResNode;
+}