[llvm] [AMDGPU] MCExpr-ify MC layer kernel descriptor (PR #80855)

[Janek van Oirschot via llvm-commits]

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@@ -0,0 +1,68 @@
+//===--- AMDGPUMCKernelDescriptor.h ---------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+/// \file
+/// AMDHSA kernel descriptor MCExpr struct for use in MC layer. Uses
+/// AMDHSAKernelDescriptor.h for sizes and constants.
+///
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_TARGET_AMDGPU_MCTARGETDESC_AMDGPUMCKERNELDESCRIPTOR_H
+#define LLVM_LIB_TARGET_AMDGPU_MCTARGETDESC_AMDGPUMCKERNELDESCRIPTOR_H
+
+#include "llvm/Support/AMDHSAKernelDescriptor.h"
+
+namespace llvm {
+class MCExpr;
+class MCContext;
+namespace AMDGPU {
+
+struct MCKernelDescriptor {
+  const MCExpr *group_segment_fixed_size = nullptr;
+  const MCExpr *private_segment_fixed_size = nullptr;
+  const MCExpr *kernarg_size = nullptr;
+  const MCExpr *compute_pgm_rsrc3 = nullptr;
+  const MCExpr *compute_pgm_rsrc1 = nullptr;
+  const MCExpr *compute_pgm_rsrc2 = nullptr;
+  const MCExpr *kernel_code_properties = nullptr;
+  const MCExpr *kernarg_preload = nullptr;
+
+  static void bits_set(const MCExpr *&Dst, const MCExpr *Value, uint32_t Shift,
+                       uint32_t Mask, MCContext &Ctx);
+  static const MCExpr *bits_get(const MCExpr *Src, uint32_t Shift,
+                                uint32_t Mask, MCContext &Ctx);
+};
+
+enum : uint32_t {
+  SIZEOF_GROUP_SEGMENT_FIXED_SIZE =
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JanekvO wrote:

You're right in that they weren't needed anymore after moving the MCExpr kernel descriptor into its own struct. I've opted to removed them altogether and replace all with the sizeof of the original struct members (albeit, some sizeofs are very namespace-verbose).

https://github.com/llvm/llvm-project/pull/80855