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

[Sergei Barannikov via llvm-commits]

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@@ -0,0 +1,72 @@
+//===-- XtensaSubtarget.h - Define Subtarget for the Xtensa ----*- C++ -*--===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// 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 declares the Xtensa specific subclass of TargetSubtargetInfo.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_TARGET_XTENSA_XTENSASUBTARGET_H
+#define LLVM_LIB_TARGET_XTENSA_XTENSASUBTARGET_H
+
+#include "XtensaFrameLowering.h"
+#include "XtensaISelLowering.h"
+#include "XtensaInstrInfo.h"
+#include "XtensaRegisterInfo.h"
+#include "llvm/CodeGen/SelectionDAGTargetInfo.h"
+#include "llvm/CodeGen/TargetSubtargetInfo.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/Target/TargetMachine.h"
+
+#define GET_SUBTARGETINFO_HEADER
+#include "XtensaGenSubtargetInfo.inc"
+
+namespace llvm {
+class StringRef;
+
+class XtensaSubtarget : public XtensaGenSubtargetInfo {
+private:
+  Triple TargetTriple;
+  XtensaInstrInfo InstrInfo;
+  XtensaTargetLowering TLInfo;
+  SelectionDAGTargetInfo TSInfo;
+  XtensaFrameLowering FrameLowering;
+
+  // Enabled Xtensa Density extension
+  bool HasDensity;
+
+  XtensaSubtarget &initializeSubtargetDependencies(StringRef CPU, StringRef FS);
+
+public:
+  XtensaSubtarget(const Triple &TT, const std::string &CPU,
+                  const std::string &FS, const TargetMachine &TM);
+
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s-barannikov wrote:

Yes, but this is a very minor issue. Most backends pass it anyway.

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