Split arch data into separate files.

Add an ArchEnum to express the arch of the Elf objects and Reg objects.

Split out the regs code into per arch pieces and generic parts.
Also, split out the header files for each arch.

Do not break out the test code yet, there isn't enough and it doesn't
help to maintain the tests.

Test: libunwindstack/libbacktrace/debuggerd unit tests pass.
Test: Running debuggerd -b <PIDS> yields valid data on bullhead.
Change-Id: If61f6c730c9ff2249f986b41de8c4d62f7158325

1 files changed, 148 insertions, 0 deletions

diff --git a/libunwindstack/RegsArm64.cpp b/libunwindstack/RegsArm64.cpp
new file mode 100644
index 000000000..2077bc5ff
--- /dev/null
+++ b/libunwindstack/RegsArm64.cpp
@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdint.h>
+
+#include <functional>
+
+#include <unwindstack/Elf.h>
+#include <unwindstack/MapInfo.h>
+#include <unwindstack/Memory.h>
+#include <unwindstack/RegsArm64.h>
+
+#include "MachineArm64.h"
+#include "UcontextArm64.h"
+#include "UserArm64.h"
+
+namespace unwindstack {
+
+RegsArm64::RegsArm64()
+    : RegsImpl<uint64_t>(ARM64_REG_LAST, ARM64_REG_SP, Location(LOCATION_REGISTER, ARM64_REG_LR)) {}
+
+ArchEnum RegsArm64::Arch() {
+  return ARCH_ARM64;
+}
+
+uint64_t RegsArm64::GetAdjustedPc(uint64_t rel_pc, Elf* elf) {
+  if (!elf->valid()) {
+    return rel_pc;
+  }
+
+  if (rel_pc < 4) {
+    return rel_pc;
+  }
+  return rel_pc - 4;
+}
+
+void RegsArm64::SetFromRaw() {
+  set_pc(regs_[ARM64_REG_PC]);
+  set_sp(regs_[ARM64_REG_SP]);
+}
+
+bool RegsArm64::SetPcFromReturnAddress(Memory*) {
+  if (pc() == regs_[ARM64_REG_LR]) {
+    return false;
+  }
+
+  set_pc(regs_[ARM64_REG_LR]);
+  return true;
+}
+
+void RegsArm64::IterateRegisters(std::function<void(const char*, uint64_t)> fn) {
+  fn("x0", regs_[ARM64_REG_R0]);
+  fn("x1", regs_[ARM64_REG_R1]);
+  fn("x2", regs_[ARM64_REG_R2]);
+  fn("x3", regs_[ARM64_REG_R3]);
+  fn("x4", regs_[ARM64_REG_R4]);
+  fn("x5", regs_[ARM64_REG_R5]);
+  fn("x6", regs_[ARM64_REG_R6]);
+  fn("x7", regs_[ARM64_REG_R7]);
+  fn("x8", regs_[ARM64_REG_R8]);
+  fn("x9", regs_[ARM64_REG_R9]);
+  fn("x10", regs_[ARM64_REG_R10]);
+  fn("x11", regs_[ARM64_REG_R11]);
+  fn("x12", regs_[ARM64_REG_R12]);
+  fn("x13", regs_[ARM64_REG_R13]);
+  fn("x14", regs_[ARM64_REG_R14]);
+  fn("x15", regs_[ARM64_REG_R15]);
+  fn("x16", regs_[ARM64_REG_R16]);
+  fn("x17", regs_[ARM64_REG_R17]);
+  fn("x18", regs_[ARM64_REG_R18]);
+  fn("x19", regs_[ARM64_REG_R19]);
+  fn("x20", regs_[ARM64_REG_R20]);
+  fn("x21", regs_[ARM64_REG_R21]);
+  fn("x22", regs_[ARM64_REG_R22]);
+  fn("x23", regs_[ARM64_REG_R23]);
+  fn("x24", regs_[ARM64_REG_R24]);
+  fn("x25", regs_[ARM64_REG_R25]);
+  fn("x26", regs_[ARM64_REG_R26]);
+  fn("x27", regs_[ARM64_REG_R27]);
+  fn("x28", regs_[ARM64_REG_R28]);
+  fn("x29", regs_[ARM64_REG_R29]);
+  fn("sp", regs_[ARM64_REG_SP]);
+  fn("lr", regs_[ARM64_REG_LR]);
+  fn("pc", regs_[ARM64_REG_PC]);
+}
+
+Regs* RegsArm64::Read(void* remote_data) {
+  arm64_user_regs* user = reinterpret_cast<arm64_user_regs*>(remote_data);
+
+  RegsArm64* regs = new RegsArm64();
+  memcpy(regs->RawData(), &user->regs[0], (ARM64_REG_R31 + 1) * sizeof(uint64_t));
+  uint64_t* reg_data = reinterpret_cast<uint64_t*>(regs->RawData());
+  reg_data[ARM64_REG_PC] = user->pc;
+  reg_data[ARM64_REG_SP] = user->sp;
+  regs->SetFromRaw();
+  return regs;
+}
+
+Regs* RegsArm64::CreateFromUcontext(void* ucontext) {
+  arm64_ucontext_t* arm64_ucontext = reinterpret_cast<arm64_ucontext_t*>(ucontext);
+
+  RegsArm64* regs = new RegsArm64();
+  memcpy(regs->RawData(), &arm64_ucontext->uc_mcontext.regs[0], ARM64_REG_LAST * sizeof(uint64_t));
+  regs->SetFromRaw();
+  return regs;
+}
+
+bool RegsArm64::StepIfSignalHandler(uint64_t rel_pc, Elf* elf, Memory* process_memory) {
+  uint64_t data;
+  Memory* elf_memory = elf->memory();
+  // Read from elf memory since it is usually more expensive to read from
+  // process memory.
+  if (!elf_memory->ReadFully(rel_pc, &data, sizeof(data))) {
+    return false;
+  }
+
+  // Look for the kernel sigreturn function.
+  // __kernel_rt_sigreturn:
+  // 0xd2801168     mov x8, #0x8b
+  // 0xd4000001     svc #0x0
+  if (data != 0xd4000001d2801168ULL) {
+    return false;
+  }
+
+  // SP + sizeof(siginfo_t) + uc_mcontext offset + X0 offset.
+  if (!process_memory->ReadFully(sp() + 0x80 + 0xb0 + 0x08, regs_.data(),
+                                 sizeof(uint64_t) * ARM64_REG_LAST)) {
+    return false;
+  }
+
+  SetFromRaw();
+  return true;
+}
+
+}  // namespace unwindstack