[Lldb-commits] [lldb] [lldb][FreeBSDKernel] Implement trapframe unwinding (PR #192184)

[David Spickett via lldb-commits]

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@@ -0,0 +1,60 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "PlatformFreeBSDKernel.h"
+
+#include <cstddef>
+#if defined(__FreeBSD__) && defined(__aarch64__)
+#include <machine/frame.h>
+#endif
+
+using namespace lldb_private::platform_freebsdkernel;
+
+// DWARF register numbers for AArch64.
+static constexpr uint32_t kDwarfSP = 31;
+static constexpr uint32_t kDwarfPC = 32;
+static constexpr uint32_t kDwarfLR = 30;   // x30
+static constexpr uint32_t kDwarfCPSR = 33; // PSTATE / CPSR
+
+// Trapframe byte offsets.
+// struct trapframe layout (sys/arm64/include/frame.h, FreeBSD 14+):
+static constexpr int32_t kTfSP = 0;
+static constexpr int32_t kTfLR = 8;
+static constexpr int32_t kTfELR = 16;    // saved PC
+static constexpr int32_t kTfSPSR = 24;   // cpsr
+static constexpr int32_t kTfX0Base = 48; // tf_x[0]; tf_x[n] = kTfX0Base + n*8
+
+#if defined(__FreeBSD__) && defined(__aarch64__)
+static_assert(offsetof(struct trapframe, tf_sp) == (size_t)kTfSP,
+              "tf_sp offset mismatch");
+static_assert(offsetof(struct trapframe, tf_lr) == (size_t)kTfLR,
+              "tf_lr offset mismatch");
+static_assert(offsetof(struct trapframe, tf_elr) == (size_t)kTfELR,
+              "tf_elr offset mismatch");
+static_assert(offsetof(struct trapframe, tf_spsr) == (size_t)kTfSPSR,
+              "tf_spsr offset mismatch");
+static_assert(offsetof(struct trapframe, tf_x[0]) == (size_t)kTfX0Base,
+              "tf_x[0] offset mismatch");
+#endif
+
+lldb::UnwindPlanSP
+PlatformFreeBSDKernel::GetTrapframeUnwindPlan_arm64(ConstString name) {
+  std::vector<std::pair<uint32_t, int32_t>> regs;
+  regs.reserve(33);
+
+  regs.push_back({kDwarfSP, kTfSP});
+  regs.push_back({kDwarfLR, kTfLR});
+  regs.push_back({kDwarfPC, kTfELR});
+  regs.push_back({kDwarfCPSR, kTfSPSR});
+
+  for (int i = 0; i <= 29; i++)
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DavidSpickett wrote:

`uint32_t i`, and then you don't need to cast.

https://github.com/llvm/llvm-project/pull/192184