[llvm] [Xtensa] Initial codegen support from IR (PR #78548)

[Sergei Barannikov via llvm-commits]

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@@ -0,0 +1,58 @@
+//===- XtensaISelLowering.cpp - Xtensa DAG Lowering Implementation --------===//
+//
+// 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 file defines the interfaces that Xtensa uses to lower LLVM code into a
+// selection DAG.
+//
+//===----------------------------------------------------------------------===//
+
+#include "XtensaISelLowering.h"
+#include "XtensaSubtarget.h"
+#include "XtensaTargetMachine.h"
+#include "llvm/CodeGen/CallingConvLower.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineJumpTableInfo.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+#define DEBUG_TYPE "xtensa-lower"
+
+XtensaTargetLowering::XtensaTargetLowering(const TargetMachine &tm,
+                                           const XtensaSubtarget &STI)
+    : TargetLowering(tm), Subtarget(STI) {
----------------
s-barannikov wrote:

```suggestion
XtensaTargetLowering::XtensaTargetLowering(const TargetMachine &TM,
                                           const XtensaSubtarget &STI)
    : TargetLowering(TM), Subtarget(STI) {
```

https://github.com/llvm/llvm-project/pull/78548