[Lldb-commits] [lldb] [LLDB][Process/Utility] Introduce NativeRegisterContextDBReg class (PR #118043)

[David Spickett via lldb-commits]

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@@ -0,0 +1,90 @@
+//===-- NativeRegisterContextDBReg.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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef lldb_NativeRegisterContextDBReg_h
+#define lldb_NativeRegisterContextDBReg_h
+
+#include "Plugins/Process/Utility/NativeRegisterContextRegisterInfo.h"
+
+#include <array>
+
+namespace lldb_private {
+
+class NativeRegisterContextDBReg
+    : public virtual NativeRegisterContextRegisterInfo {
+public:
+  uint32_t NumSupportedHardwareBreakpoints() override;
+
+  uint32_t SetHardwareBreakpoint(lldb::addr_t addr, size_t size) override;
+
+  bool ClearHardwareBreakpoint(uint32_t hw_idx) override;
+
+  Status ClearAllHardwareBreakpoints() override;
+
+  Status GetHardwareBreakHitIndex(uint32_t &bp_index,
+                                  lldb::addr_t trap_addr) override;
+
+  uint32_t NumSupportedHardwareWatchpoints() override;
+
+  uint32_t SetHardwareWatchpoint(lldb::addr_t addr, size_t size,
+                                 uint32_t watch_flags) override;
+
+  bool ClearHardwareWatchpoint(uint32_t hw_index) override;
+
+  Status ClearAllHardwareWatchpoints() override;
+
+  Status GetWatchpointHitIndex(uint32_t &wp_index,
+                               lldb::addr_t trap_addr) override;
+
+  lldb::addr_t GetWatchpointHitAddress(uint32_t wp_index) override;
+
+  lldb::addr_t GetWatchpointAddress(uint32_t wp_index) override;
+
+protected:
+  // Debug register type select
+  enum DREGType { eDREGTypeWATCH = 0, eDREGTypeBREAK };
+
+  /// Debug register info for hardware breakpoints and watchpoints management.
+  struct DREG {
+    lldb::addr_t address;  // Breakpoint/watchpoint address value.
+    lldb::addr_t hit_addr; // Address at which last watchpoint trigger exception
+                           // occurred.
+    lldb::addr_t real_addr; // Address value that should cause target to stop.
+    uint32_t control;       // Breakpoint/watchpoint control value.
+  };
+
+  std::array<struct DREG, 16> m_hbp_regs; // hardware breakpoints
+  std::array<struct DREG, 16> m_hwp_regs; // hardware watchpoints
+
+  uint32_t m_max_hbp_supported;
+  uint32_t m_max_hwp_supported;
+  uint32_t m_hw_dbg_enable_bit;
+
+  bool WatchpointIsEnabled(uint32_t wp_index);
+  bool BreakpointIsEnabled(uint32_t bp_index);
+
+  // Default hardware breakpoint length size is 4.
+  // Default hardware breakpoint target address must 4-byte alignment.
+  virtual bool ValidateBreakpoint(size_t size, lldb::addr_t addr) {
+    return (size == 4) && !(addr & 0x3);
----------------
DavidSpickett wrote:

If these specific checks are common to AArch64 and LoongArch, this is fine. You could remove `virtual` if so.

If this is just the AArch64 checks, I think it might be better to make this an abstract method. Just so that future programmers are forced to confirm what their architecture requires, and they can find existing rules by looking at the arch specific class, rather than having to know that one uses the base implementation.

https://github.com/llvm/llvm-project/pull/118043