Add the Dwarf CFA handling.

Bug: 23762183

Test: Ran new unit tests.
Change-Id: I31abac1238cc671b78a505da655fb6298be072b4
diff --git a/libunwindstack/DwarfCfa.cpp b/libunwindstack/DwarfCfa.cpp
new file mode 100644
index 0000000..006f039
--- /dev/null
+++ b/libunwindstack/DwarfCfa.cpp
@@ -0,0 +1,713 @@
+/*
+ * 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 <inttypes.h>
+#include <stdint.h>
+
+#include <string>
+#include <type_traits>
+#include <vector>
+
+#include <android-base/stringprintf.h>
+
+#include "DwarfCfa.h"
+#include "DwarfEncoding.h"
+#include "DwarfMemory.h"
+#include "DwarfOp.h"
+#include "DwarfStructs.h"
+#include "Log.h"
+
+template <typename AddressType>
+constexpr typename DwarfCfa<AddressType>::process_func DwarfCfa<AddressType>::kCallbackTable[64];
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::GetLocationInfo(uint64_t pc, uint64_t start_offset, uint64_t end_offset,
+                                            dwarf_loc_regs_t* loc_regs) {
+  if (cie_loc_regs_ != nullptr) {
+    for (const auto& entry : *cie_loc_regs_) {
+      (*loc_regs)[entry.first] = entry.second;
+    }
+  }
+  last_error_ = DWARF_ERROR_NONE;
+
+  memory_->set_cur_offset(start_offset);
+  uint64_t cfa_offset;
+  cur_pc_ = fde_->pc_start;
+  while ((cfa_offset = memory_->cur_offset()) < end_offset && cur_pc_ <= pc) {
+    operands_.clear();
+    // Read the cfa information.
+    uint8_t cfa_value;
+    if (!memory_->ReadBytes(&cfa_value, 1)) {
+      last_error_ = DWARF_ERROR_MEMORY_INVALID;
+      return false;
+    }
+    uint8_t cfa_low = cfa_value & 0x3f;
+    // Check the 2 high bits.
+    switch (cfa_value >> 6) {
+      case 1:
+        cur_pc_ += cfa_low * fde_->cie->code_alignment_factor;
+        break;
+      case 2: {
+        uint64_t offset;
+        if (!memory_->ReadULEB128(&offset)) {
+          last_error_ = DWARF_ERROR_MEMORY_INVALID;
+          return false;
+        }
+        SignedType signed_offset =
+            static_cast<SignedType>(offset) * fde_->cie->data_alignment_factor;
+        (*loc_regs)[cfa_low] = {.type = DWARF_LOCATION_OFFSET,
+                                .values = {static_cast<uint64_t>(signed_offset)}};
+        break;
+      }
+      case 3: {
+        if (cie_loc_regs_ == nullptr) {
+          log(0, "restore while processing cie");
+          last_error_ = DWARF_ERROR_ILLEGAL_STATE;
+          return false;
+        }
+
+        auto reg_entry = cie_loc_regs_->find(cfa_low);
+        if (reg_entry == cie_loc_regs_->end()) {
+          loc_regs->erase(cfa_low);
+        } else {
+          (*loc_regs)[cfa_low] = reg_entry->second;
+        }
+        break;
+      }
+      case 0: {
+        const auto handle_func = DwarfCfa<AddressType>::kCallbackTable[cfa_low];
+        if (handle_func == nullptr) {
+          last_error_ = DWARF_ERROR_ILLEGAL_VALUE;
+          return false;
+        }
+
+        const auto cfa = &DwarfCfaInfo::kTable[cfa_low];
+        for (size_t i = 0; i < cfa->num_operands; i++) {
+          if (cfa->operands[i] == DW_EH_PE_block) {
+            uint64_t block_length;
+            if (!memory_->ReadULEB128(&block_length)) {
+              last_error_ = DWARF_ERROR_MEMORY_INVALID;
+              return false;
+            }
+            operands_.push_back(block_length);
+            memory_->set_cur_offset(memory_->cur_offset() + block_length);
+            continue;
+          }
+          uint64_t value;
+          if (!memory_->ReadEncodedValue<AddressType>(cfa->operands[i], &value)) {
+            last_error_ = DWARF_ERROR_MEMORY_INVALID;
+            return false;
+          }
+          operands_.push_back(value);
+        }
+
+        if (!(this->*handle_func)(loc_regs)) {
+          return false;
+        }
+        break;
+      }
+    }
+  }
+  return true;
+}
+
+template <typename AddressType>
+std::string DwarfCfa<AddressType>::GetOperandString(uint8_t operand, uint64_t value,
+                                                    uint64_t* cur_pc) {
+  std::string string;
+  switch (operand) {
+    case DwarfCfaInfo::DWARF_DISPLAY_REGISTER:
+      string = " register(" + std::to_string(value) + ")";
+      break;
+    case DwarfCfaInfo::DWARF_DISPLAY_SIGNED_NUMBER:
+      string += " " + std::to_string(static_cast<SignedType>(value));
+      break;
+    case DwarfCfaInfo::DWARF_DISPLAY_ADVANCE_LOC:
+      *cur_pc += value;
+    // Fall through to log the value.
+    case DwarfCfaInfo::DWARF_DISPLAY_NUMBER:
+      string += " " + std::to_string(value);
+      break;
+    case DwarfCfaInfo::DWARF_DISPLAY_SET_LOC:
+      *cur_pc = value;
+    // Fall through to log the value.
+    case DwarfCfaInfo::DWARF_DISPLAY_ADDRESS:
+      if (std::is_same<AddressType, uint32_t>::value) {
+        string += android::base::StringPrintf(" 0x%" PRIx32, static_cast<uint32_t>(value));
+      } else {
+        string += android::base::StringPrintf(" 0x%" PRIx64, static_cast<uint64_t>(value));
+      }
+      break;
+    default:
+      string = " unknown";
+  }
+  return string;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::LogOffsetRegisterString(uint32_t indent, uint64_t cfa_offset,
+                                                    uint8_t reg) {
+  uint64_t offset;
+  if (!memory_->ReadULEB128(&offset)) {
+    return false;
+  }
+  uint64_t end_offset = memory_->cur_offset();
+  memory_->set_cur_offset(cfa_offset);
+
+  std::string raw_data = "Raw Data:";
+  for (uint64_t i = cfa_offset; i < end_offset; i++) {
+    uint8_t value;
+    if (!memory_->ReadBytes(&value, 1)) {
+      return false;
+    }
+    raw_data += android::base::StringPrintf(" 0x%02x", value);
+  }
+  log(indent, "DW_CFA_offset register(%d) %" PRId64, reg, offset);
+  log(indent, "%s", raw_data.c_str());
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::LogInstruction(uint32_t indent, uint64_t cfa_offset, uint8_t op,
+                                           uint64_t* cur_pc) {
+  const auto* cfa = &DwarfCfaInfo::kTable[op];
+  if (cfa->name == nullptr) {
+    log(indent, "Illegal");
+    log(indent, "Raw Data: 0x%02x", op);
+    return true;
+  }
+
+  std::string log_string(cfa->name);
+  std::vector<std::string> expression_lines;
+  for (size_t i = 0; i < cfa->num_operands; i++) {
+    if (cfa->operands[i] == DW_EH_PE_block) {
+      // This is a Dwarf Expression.
+      uint64_t end_offset;
+      if (!memory_->ReadULEB128(&end_offset)) {
+        return false;
+      }
+      log_string += " " + std::to_string(end_offset);
+      end_offset += memory_->cur_offset();
+
+      DwarfOp<AddressType> op(memory_, nullptr);
+      op.GetLogInfo(memory_->cur_offset(), end_offset, &expression_lines);
+      memory_->set_cur_offset(end_offset);
+    } else {
+      uint64_t value;
+      if (!memory_->ReadEncodedValue<AddressType>(cfa->operands[i], &value)) {
+        return false;
+      }
+      log_string += GetOperandString(cfa->display_operands[i], value, cur_pc);
+    }
+  }
+  log(indent, "%s", log_string.c_str());
+
+  // Get the raw bytes of the data.
+  uint64_t end_offset = memory_->cur_offset();
+  memory_->set_cur_offset(cfa_offset);
+  std::string raw_data("Raw Data:");
+  for (uint64_t i = 0; i < end_offset - cfa_offset; i++) {
+    uint8_t value;
+    if (!memory_->ReadBytes(&value, 1)) {
+      return false;
+    }
+
+    // Only show 10 raw bytes per line.
+    if ((i % 10) == 0 && i != 0) {
+      log(indent, "%s", raw_data.c_str());
+      raw_data.clear();
+    }
+    if (raw_data.empty()) {
+      raw_data = "Raw Data:";
+    }
+    raw_data += android::base::StringPrintf(" 0x%02x", value);
+  }
+  if (!raw_data.empty()) {
+    log(indent, "%s", raw_data.c_str());
+  }
+
+  // Log any of the expression data.
+  for (const auto line : expression_lines) {
+    log(indent + 1, "%s", line.c_str());
+  }
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::Log(uint32_t indent, uint64_t pc, uint64_t load_bias,
+                                uint64_t start_offset, uint64_t end_offset) {
+  memory_->set_cur_offset(start_offset);
+  uint64_t cfa_offset;
+  uint64_t cur_pc = fde_->pc_start;
+  uint64_t old_pc = cur_pc;
+  while ((cfa_offset = memory_->cur_offset()) < end_offset && cur_pc <= pc) {
+    // Read the cfa information.
+    uint8_t cfa_value;
+    if (!memory_->ReadBytes(&cfa_value, 1)) {
+      return false;
+    }
+
+    // Check the 2 high bits.
+    uint8_t cfa_low = cfa_value & 0x3f;
+    switch (cfa_value >> 6) {
+      case 0:
+        if (!LogInstruction(indent, cfa_offset, cfa_low, &cur_pc)) {
+          return false;
+        }
+        break;
+      case 1:
+        log(indent, "DW_CFA_advance_loc %d", cfa_low);
+        log(indent, "Raw Data: 0x%02x", cfa_value);
+        cur_pc += cfa_low * fde_->cie->code_alignment_factor;
+        break;
+      case 2:
+        if (!LogOffsetRegisterString(indent, cfa_offset, cfa_low)) {
+          return false;
+        }
+        break;
+      case 3:
+        log(indent, "DW_CFA_restore register(%d)", cfa_low);
+        log(indent, "Raw Data: 0x%02x", cfa_value);
+        break;
+    }
+    if (cur_pc != old_pc) {
+      log(indent, "");
+      log(indent, "PC 0x%" PRIx64, cur_pc + load_bias);
+    }
+    old_pc = cur_pc;
+  }
+  return true;
+}
+
+// Static data.
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_nop(dwarf_loc_regs_t*) {
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_set_loc(dwarf_loc_regs_t*) {
+  AddressType cur_pc = cur_pc_;
+  AddressType new_pc = operands_[0];
+  if (new_pc < cur_pc) {
+    if (std::is_same<AddressType, uint32_t>::value) {
+      log(0, "Warning: PC is moving backwards: old 0x%" PRIx32 " new 0x%" PRIx32, cur_pc, new_pc);
+    } else {
+      log(0, "Warning: PC is moving backwards: old 0x%" PRIx64 " new 0x%" PRIx64, cur_pc, new_pc);
+    }
+  }
+  cur_pc_ = new_pc;
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_advance_loc(dwarf_loc_regs_t*) {
+  cur_pc_ += operands_[0] * fde_->cie->code_alignment_factor;
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_offset(dwarf_loc_regs_t* loc_regs) {
+  AddressType reg = operands_[0];
+  (*loc_regs)[reg] = {.type = DWARF_LOCATION_OFFSET, .values = {operands_[1]}};
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_restore(dwarf_loc_regs_t* loc_regs) {
+  AddressType reg = operands_[0];
+  if (cie_loc_regs_ == nullptr) {
+    log(0, "restore while processing cie");
+    last_error_ = DWARF_ERROR_ILLEGAL_STATE;
+    return false;
+  }
+  auto reg_entry = cie_loc_regs_->find(reg);
+  if (reg_entry == cie_loc_regs_->end()) {
+    loc_regs->erase(reg);
+  } else {
+    (*loc_regs)[reg] = reg_entry->second;
+  }
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_undefined(dwarf_loc_regs_t* loc_regs) {
+  AddressType reg = operands_[0];
+  (*loc_regs)[reg] = {.type = DWARF_LOCATION_UNDEFINED};
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_same_value(dwarf_loc_regs_t* loc_regs) {
+  AddressType reg = operands_[0];
+  loc_regs->erase(reg);
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_register(dwarf_loc_regs_t* loc_regs) {
+  AddressType reg = operands_[0];
+  AddressType reg_dst = operands_[1];
+  (*loc_regs)[reg] = {.type = DWARF_LOCATION_REGISTER, .values = {reg_dst}};
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_remember_state(dwarf_loc_regs_t* loc_regs) {
+  loc_reg_state_.push(*loc_regs);
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_restore_state(dwarf_loc_regs_t* loc_regs) {
+  if (loc_reg_state_.size() == 0) {
+    log(0, "Warning: Attempt to restore without remember.");
+    return true;
+  }
+  *loc_regs = loc_reg_state_.top();
+  loc_reg_state_.pop();
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_def_cfa(dwarf_loc_regs_t* loc_regs) {
+  (*loc_regs)[CFA_REG] = {.type = DWARF_LOCATION_REGISTER, .values = {operands_[0], operands_[1]}};
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_def_cfa_register(dwarf_loc_regs_t* loc_regs) {
+  auto cfa_location = loc_regs->find(CFA_REG);
+  if (cfa_location == loc_regs->end() || cfa_location->second.type != DWARF_LOCATION_REGISTER) {
+    log(0, "Attempt to set new register, but cfa is not already set to a register.");
+    last_error_ = DWARF_ERROR_ILLEGAL_STATE;
+    return false;
+  }
+
+  cfa_location->second.values[0] = operands_[0];
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_def_cfa_offset(dwarf_loc_regs_t* loc_regs) {
+  // Changing the offset if this is not a register is illegal.
+  auto cfa_location = loc_regs->find(CFA_REG);
+  if (cfa_location == loc_regs->end() || cfa_location->second.type != DWARF_LOCATION_REGISTER) {
+    log(0, "Attempt to set offset, but cfa is not set to a register.");
+    last_error_ = DWARF_ERROR_ILLEGAL_STATE;
+    return false;
+  }
+  cfa_location->second.values[1] = operands_[0];
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_def_cfa_expression(dwarf_loc_regs_t* loc_regs) {
+  (*loc_regs)[CFA_REG] = {.type = DWARF_LOCATION_EXPRESSION,
+                          .values = {operands_[0], memory_->cur_offset()}};
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_expression(dwarf_loc_regs_t* loc_regs) {
+  AddressType reg = operands_[0];
+  (*loc_regs)[reg] = {.type = DWARF_LOCATION_EXPRESSION,
+                      .values = {operands_[1], memory_->cur_offset()}};
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_offset_extended_sf(dwarf_loc_regs_t* loc_regs) {
+  AddressType reg = operands_[0];
+  SignedType value = static_cast<SignedType>(operands_[1]) * fde_->cie->data_alignment_factor;
+  (*loc_regs)[reg] = {.type = DWARF_LOCATION_OFFSET, .values = {static_cast<uint64_t>(value)}};
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_def_cfa_sf(dwarf_loc_regs_t* loc_regs) {
+  SignedType offset = static_cast<SignedType>(operands_[1]) * fde_->cie->data_alignment_factor;
+  (*loc_regs)[CFA_REG] = {.type = DWARF_LOCATION_REGISTER,
+                          .values = {operands_[0], static_cast<uint64_t>(offset)}};
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_def_cfa_offset_sf(dwarf_loc_regs_t* loc_regs) {
+  // Changing the offset if this is not a register is illegal.
+  auto cfa_location = loc_regs->find(CFA_REG);
+  if (cfa_location == loc_regs->end() || cfa_location->second.type != DWARF_LOCATION_REGISTER) {
+    log(0, "Attempt to set offset, but cfa is not set to a register.");
+    last_error_ = DWARF_ERROR_ILLEGAL_STATE;
+    return false;
+  }
+  SignedType offset = static_cast<SignedType>(operands_[0]) * fde_->cie->data_alignment_factor;
+  cfa_location->second.values[1] = static_cast<uint64_t>(offset);
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_val_offset(dwarf_loc_regs_t* loc_regs) {
+  AddressType reg = operands_[0];
+  SignedType offset = static_cast<SignedType>(operands_[1]) * fde_->cie->data_alignment_factor;
+  (*loc_regs)[reg] = {.type = DWARF_LOCATION_VAL_OFFSET, .values = {static_cast<uint64_t>(offset)}};
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_val_offset_sf(dwarf_loc_regs_t* loc_regs) {
+  AddressType reg = operands_[0];
+  SignedType offset = static_cast<SignedType>(operands_[1]) * fde_->cie->data_alignment_factor;
+  (*loc_regs)[reg] = {.type = DWARF_LOCATION_VAL_OFFSET, .values = {static_cast<uint64_t>(offset)}};
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_val_expression(dwarf_loc_regs_t* loc_regs) {
+  AddressType reg = operands_[0];
+  (*loc_regs)[reg] = {.type = DWARF_LOCATION_VAL_EXPRESSION,
+                      .values = {operands_[1], memory_->cur_offset()}};
+  return true;
+}
+
+template <typename AddressType>
+bool DwarfCfa<AddressType>::cfa_gnu_negative_offset_extended(dwarf_loc_regs_t* loc_regs) {
+  AddressType reg = operands_[0];
+  SignedType offset = -static_cast<SignedType>(operands_[1]);
+  (*loc_regs)[reg] = {.type = DWARF_LOCATION_OFFSET, .values = {static_cast<uint64_t>(offset)}};
+  return true;
+}
+
+const DwarfCfaInfo::Info DwarfCfaInfo::kTable[64] = {
+    {
+        // 0x00 DW_CFA_nop
+        "DW_CFA_nop",
+        2,
+        0,
+        {},
+        {},
+    },
+    {
+        "DW_CFA_set_loc",  // 0x01 DW_CFA_set_loc
+        2,
+        1,
+        {DW_EH_PE_absptr},
+        {DWARF_DISPLAY_SET_LOC},
+    },
+    {
+        "DW_CFA_advance_loc1",  // 0x02 DW_CFA_advance_loc1
+        2,
+        1,
+        {DW_EH_PE_udata1},
+        {DWARF_DISPLAY_ADVANCE_LOC},
+    },
+    {
+        "DW_CFA_advance_loc2",  // 0x03 DW_CFA_advance_loc2
+        2,
+        1,
+        {DW_EH_PE_udata2},
+        {DWARF_DISPLAY_ADVANCE_LOC},
+    },
+    {
+        "DW_CFA_advance_loc4",  // 0x04 DW_CFA_advance_loc4
+        2,
+        1,
+        {DW_EH_PE_udata4},
+        {DWARF_DISPLAY_ADVANCE_LOC},
+    },
+    {
+        "DW_CFA_offset_extended",  // 0x05 DW_CFA_offset_extended
+        2,
+        2,
+        {DW_EH_PE_uleb128, DW_EH_PE_uleb128},
+        {DWARF_DISPLAY_REGISTER, DWARF_DISPLAY_NUMBER},
+    },
+    {
+        "DW_CFA_restore_extended",  // 0x06 DW_CFA_restore_extended
+        2,
+        1,
+        {DW_EH_PE_uleb128},
+        {DWARF_DISPLAY_REGISTER},
+    },
+    {
+        "DW_CFA_undefined",  // 0x07 DW_CFA_undefined
+        2,
+        1,
+        {DW_EH_PE_uleb128},
+        {DWARF_DISPLAY_REGISTER},
+    },
+    {
+        "DW_CFA_same_value",  // 0x08 DW_CFA_same_value
+        2,
+        1,
+        {DW_EH_PE_uleb128},
+        {DWARF_DISPLAY_REGISTER},
+    },
+    {
+        "DW_CFA_register",  // 0x09 DW_CFA_register
+        2,
+        2,
+        {DW_EH_PE_uleb128, DW_EH_PE_uleb128},
+        {DWARF_DISPLAY_REGISTER, DWARF_DISPLAY_REGISTER},
+    },
+    {
+        "DW_CFA_remember_state",  // 0x0a DW_CFA_remember_state
+        2,
+        0,
+        {},
+        {},
+    },
+    {
+        "DW_CFA_restore_state",  // 0x0b DW_CFA_restore_state
+        2,
+        0,
+        {},
+        {},
+    },
+    {
+        "DW_CFA_def_cfa",  // 0x0c DW_CFA_def_cfa
+        2,
+        2,
+        {DW_EH_PE_uleb128, DW_EH_PE_uleb128},
+        {DWARF_DISPLAY_REGISTER, DWARF_DISPLAY_NUMBER},
+    },
+    {
+        "DW_CFA_def_cfa_register",  // 0x0d DW_CFA_def_cfa_register
+        2,
+        1,
+        {DW_EH_PE_uleb128},
+        {DWARF_DISPLAY_REGISTER},
+    },
+    {
+        "DW_CFA_def_cfa_offset",  // 0x0e DW_CFA_def_cfa_offset
+        2,
+        1,
+        {DW_EH_PE_uleb128},
+        {DWARF_DISPLAY_NUMBER},
+    },
+    {
+        "DW_CFA_def_cfa_expression",  // 0x0f DW_CFA_def_cfa_expression
+        2,
+        1,
+        {DW_EH_PE_block},
+        {DWARF_DISPLAY_EVAL_BLOCK},
+    },
+    {
+        "DW_CFA_expression",  // 0x10 DW_CFA_expression
+        2,
+        2,
+        {DW_EH_PE_uleb128, DW_EH_PE_block},
+        {DWARF_DISPLAY_REGISTER, DWARF_DISPLAY_EVAL_BLOCK},
+    },
+    {
+        "DW_CFA_offset_extended_sf",  // 0x11 DW_CFA_offset_extend_sf
+        2,
+        2,
+        {DW_EH_PE_uleb128, DW_EH_PE_sleb128},
+        {DWARF_DISPLAY_REGISTER, DWARF_DISPLAY_SIGNED_NUMBER},
+    },
+    {
+        "DW_CFA_def_cfa_sf",  // 0x12 DW_CFA_def_cfa_sf
+        2,
+        2,
+        {DW_EH_PE_uleb128, DW_EH_PE_sleb128},
+        {DWARF_DISPLAY_REGISTER, DWARF_DISPLAY_SIGNED_NUMBER},
+    },
+    {
+        "DW_CFA_def_cfa_offset_sf",  // 0x13 DW_CFA_def_cfa_offset_sf
+        2,
+        1,
+        {DW_EH_PE_sleb128},
+        {DWARF_DISPLAY_SIGNED_NUMBER},
+    },
+    {
+        "DW_CFA_val_offset",  // 0x14 DW_CFA_val_offset
+        2,
+        2,
+        {DW_EH_PE_uleb128, DW_EH_PE_uleb128},
+        {DWARF_DISPLAY_REGISTER, DWARF_DISPLAY_NUMBER},
+    },
+    {
+        "DW_CFA_val_offset_sf",  // 0x15 DW_CFA_val_offset_sf
+        2,
+        2,
+        {DW_EH_PE_uleb128, DW_EH_PE_sleb128},
+        {DWARF_DISPLAY_REGISTER, DWARF_DISPLAY_SIGNED_NUMBER},
+    },
+    {
+        "DW_CFA_val_expression",  // 0x16 DW_CFA_val_expression
+        2,
+        2,
+        {DW_EH_PE_uleb128, DW_EH_PE_block},
+        {DWARF_DISPLAY_REGISTER, DWARF_DISPLAY_EVAL_BLOCK},
+    },
+    {nullptr, 0, 0, {}, {}},  // 0x17 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x18 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x19 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x1a illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x1b illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x1c DW_CFA_lo_user (Treat as illegal)
+    {nullptr, 0, 0, {}, {}},  // 0x1d illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x1e illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x1f illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x20 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x21 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x22 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x23 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x24 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x25 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x26 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x27 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x28 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x29 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x2a illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x2b illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x2c illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x2d DW_CFA_GNU_window_save (Treat as illegal)
+    {
+        "DW_CFA_GNU_args_size",  // 0x2e DW_CFA_GNU_args_size
+        2,
+        1,
+        {DW_EH_PE_uleb128},
+        {DWARF_DISPLAY_NUMBER},
+    },
+    {
+        "DW_CFA_GNU_negative_offset_extended",  // 0x2f DW_CFA_GNU_negative_offset_extended
+        2,
+        2,
+        {DW_EH_PE_uleb128, DW_EH_PE_uleb128},
+        {DWARF_DISPLAY_REGISTER, DWARF_DISPLAY_NUMBER},
+    },
+    {nullptr, 0, 0, {}, {}},  // 0x31 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x32 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x33 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x34 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x35 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x36 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x37 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x38 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x39 illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x3a illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x3b illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x3c illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x3d illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x3e illegal cfa
+    {nullptr, 0, 0, {}, {}},  // 0x3f DW_CFA_hi_user (Treat as illegal)
+};
+
+// Explicitly instantiate DwarfCfa.
+template class DwarfCfa<uint32_t>;
+template class DwarfCfa<uint64_t>;