[LoongArch 4/6] Add basic tablegen infra for LoongArch

This patch introduces basic tablegen infra such as
LoongArch{InstrFormats,InstrInfo,RegisterInfo,CallingConv,}.td.

For now, only add instruction definitions for LoongArch basic integer
operations.
Our initial target is a working MC layer rather than codegen,
so appropriate SelectionDAG patterns will come later.

Differential revision: https://reviews.llvm.org/D115861

1 files changed, 38 insertions, 0 deletions

diff --git a/llvm/lib/Target/LoongArch/LoongArchFrameLowering.h b/llvm/lib/Target/LoongArch/LoongArchFrameLowering.h
new file mode 100644
index 0000000..25c53efc
--- /dev/null
+++ b/llvm/lib/Target/LoongArch/LoongArchFrameLowering.h
@@ -0,0 +1,38 @@
+//=- LoongArchFrameLowering.h - TargetFrameLowering for LoongArch -*- C++ -*--//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This class implements LoongArch-specific bits of TargetFrameLowering class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_TARGET_LOONGARCH_LOONGARCHFRAMELOWERING_H
+#define LLVM_LIB_TARGET_LOONGARCH_LOONGARCHFRAMELOWERING_H
+
+#include "llvm/CodeGen/TargetFrameLowering.h"
+
+namespace llvm {
+class LoongArchSubtarget;
+
+class LoongArchFrameLowering : public TargetFrameLowering {
+  const LoongArchSubtarget &STI;
+
+public:
+  explicit LoongArchFrameLowering(const LoongArchSubtarget &STI)
+      : TargetFrameLowering(StackGrowsDown,
+                            /*StackAlignment=*/Align(16),
+                            /*LocalAreaOffset=*/0),
+        STI(STI) {}
+
+  void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
+  void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
+
+  bool hasFP(const MachineFunction &MF) const override;
+  bool hasBP(const MachineFunction &MF) const;
+};
+} // namespace llvm
+#endif // LLVM_LIB_TARGET_LOONGARCH_LOONGARCHFRAMELOWERING_H