Add skeleton of simple basic block instruction selector.

llvm-svn: 54522

1 files changed, 29 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SimpleBBISel.cpp b/llvm/lib/CodeGen/SelectionDAG/SimpleBBISel.cpp
new file mode 100644
index 00000000000..1200cd3b0d5
--- /dev/null
+++ b/llvm/lib/CodeGen/SelectionDAG/SimpleBBISel.cpp
@@ -0,0 +1,29 @@
+//===-- SimpleBBISel.cpp - Implement the SimpleBBISel class ---------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This implements simple basic block instruction selection. If the given
+// BasicBlock is considered "simple", i.e. all operations are supported by
+// the target and their types are legal, it does instruction directly from
+// LLVM BasicBlock to MachineInstr's.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "simple-isel"
+#include "SimpleBBISel.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/SelectionDAG.h"
+using namespace llvm;
+
+/// SelectBasicBlock - Try to convert a LLVM basic block into a
+/// MachineBasicBlock using simple instruction selection. Returns false if it
+/// is not able to do so.
+bool SimpleBBISel::SelectBasicBlock(BasicBlock *BB, MachineBasicBlock *MBB) {
+  return false;
+}