[llvm] [Xtensa] Implement base CallConvention. (PR #83280)

[Sergei Barannikov via llvm-commits]

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@@ -0,0 +1,60 @@
+//===--- XtensaUtils.cpp ---- Xtensa Utility Functions ----------*- 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 file contains miscellaneous utility functions.
+//
+//===----------------------------------------------------------------------===//
+
+#include "XtensaUtils.h"
+
+namespace llvm {
+
+// Check address offset for load/store instructions
+// The offset should be multiple of scale
+bool isValidAddrOffset(int Scale, int64_t OffsetVal) {
+  bool Valid = false;
+
+  switch (Scale) {
+  case 1:
+    Valid = (OffsetVal >= 0 && OffsetVal <= 255);
+    break;
+  case 2:
+    Valid = (OffsetVal >= 0 && OffsetVal <= 510) && ((OffsetVal & 0x1) == 0);
+    break;
+  case 4:
+    Valid = (OffsetVal >= 0 && OffsetVal <= 1020) && ((OffsetVal & 0x3) == 0);
+    break;
+  default:
+    break;
+  }
+  return Valid;
+}
+
+// Check address offset for load/store instructions
+bool isValidAddrOffset(MachineInstr &MI, int64_t Offset) {
+  int Scale = 0;
+
+  switch (MI.getOpcode()) {
+  case Xtensa::L8UI:
+  case Xtensa::S8I:
+    Scale = 1;
+    break;
+  case Xtensa::L16SI:
+  case Xtensa::L16UI:
+  case Xtensa::S16I:
+    Scale = 2;
+    break;
+  default:
+    // assume that MI is 32-bit load/store operation
+    Scale = 4;
+    break;
+  }
+  return isValidAddrOffset(Scale, Offset);
+}
+
+} // namespace llvm
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s-barannikov wrote:

newline at end of file

https://github.com/llvm/llvm-project/pull/83280