Add the Dwarf CFA handling.

Bug: 23762183

Test: Ran new unit tests.
Change-Id: I31abac1238cc671b78a505da655fb6298be072b4

1 files changed, 255 insertions, 0 deletions

diff --git a/libunwindstack/DwarfCfa.h b/libunwindstack/DwarfCfa.h
new file mode 100644
index 0000000..ce7da4a
--- /dev/null
+++ b/libunwindstack/DwarfCfa.h
@@ -0,0 +1,255 @@
+/*
+ * 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.
+ */
+
+#ifndef _LIBUNWINDSTACK_DWARF_CFA_H
+#define _LIBUNWINDSTACK_DWARF_CFA_H
+
+#include <stdint.h>
+
+#include <stack>
+#include <string>
+#include <type_traits>
+#include <vector>
+
+#include "DwarfError.h"
+#include "DwarfLocation.h"
+#include "DwarfMemory.h"
+#include "DwarfStructs.h"
+
+// DWARF Standard home: http://dwarfstd.org/
+// This code is based on DWARF 4: http://http://dwarfstd.org/doc/DWARF4.pdf
+// See section 6.4.2.1 for a description of the DW_CFA_xxx values.
+
+class DwarfCfaInfo {
+ public:
+  enum DisplayType : uint8_t {
+    DWARF_DISPLAY_NONE = 0,
+    DWARF_DISPLAY_REGISTER,
+    DWARF_DISPLAY_NUMBER,
+    DWARF_DISPLAY_SIGNED_NUMBER,
+    DWARF_DISPLAY_EVAL_BLOCK,
+    DWARF_DISPLAY_ADDRESS,
+    DWARF_DISPLAY_SET_LOC,
+    DWARF_DISPLAY_ADVANCE_LOC,
+  };
+
+  struct Info {
+    const char* name;
+    uint8_t supported_version;
+    uint8_t num_operands;
+    uint8_t operands[2];
+    uint8_t display_operands[2];
+  };
+
+  const static Info kTable[64];
+};
+
+template <typename AddressType>
+class DwarfCfa {
+  // Signed version of AddressType
+  typedef typename std::make_signed<AddressType>::type SignedType;
+
+ public:
+  DwarfCfa(DwarfMemory* memory, const DwarfFDE* fde) : memory_(memory), fde_(fde) {}
+  virtual ~DwarfCfa() = default;
+
+  bool GetLocationInfo(uint64_t pc, uint64_t start_offset, uint64_t end_offset,
+                       dwarf_loc_regs_t* loc_regs);
+
+  bool Log(uint32_t indent, uint64_t pc, uint64_t load_bias, uint64_t start_offset,
+           uint64_t end_offset);
+
+  DwarfError last_error() { return last_error_; }
+
+  AddressType cur_pc() { return cur_pc_; }
+
+  void set_cie_loc_regs(const dwarf_loc_regs_t* cie_loc_regs) { cie_loc_regs_ = cie_loc_regs; }
+
+ protected:
+  std::string GetOperandString(uint8_t operand, uint64_t value, uint64_t* cur_pc);
+
+  bool LogOffsetRegisterString(uint32_t indent, uint64_t cfa_offset, uint8_t reg);
+
+  bool LogInstruction(uint32_t indent, uint64_t cfa_offset, uint8_t op, uint64_t* cur_pc);
+
+ private:
+  DwarfError last_error_;
+  DwarfMemory* memory_;
+  const DwarfFDE* fde_;
+
+  AddressType cur_pc_;
+  const dwarf_loc_regs_t* cie_loc_regs_ = nullptr;
+  std::vector<AddressType> operands_;
+  std::stack<dwarf_loc_regs_t> loc_reg_state_;
+
+  // CFA processing functions.
+  bool cfa_nop(dwarf_loc_regs_t*);
+  bool cfa_set_loc(dwarf_loc_regs_t*);
+  bool cfa_advance_loc(dwarf_loc_regs_t*);
+  bool cfa_offset(dwarf_loc_regs_t*);
+  bool cfa_restore(dwarf_loc_regs_t*);
+  bool cfa_undefined(dwarf_loc_regs_t*);
+  bool cfa_same_value(dwarf_loc_regs_t*);
+  bool cfa_register(dwarf_loc_regs_t*);
+  bool cfa_remember_state(dwarf_loc_regs_t*);
+  bool cfa_restore_state(dwarf_loc_regs_t*);
+  bool cfa_def_cfa(dwarf_loc_regs_t*);
+  bool cfa_def_cfa_register(dwarf_loc_regs_t*);
+  bool cfa_def_cfa_offset(dwarf_loc_regs_t*);
+  bool cfa_def_cfa_expression(dwarf_loc_regs_t*);
+  bool cfa_expression(dwarf_loc_regs_t*);
+  bool cfa_offset_extended_sf(dwarf_loc_regs_t*);
+  bool cfa_def_cfa_sf(dwarf_loc_regs_t*);
+  bool cfa_def_cfa_offset_sf(dwarf_loc_regs_t*);
+  bool cfa_val_offset(dwarf_loc_regs_t*);
+  bool cfa_val_offset_sf(dwarf_loc_regs_t*);
+  bool cfa_val_expression(dwarf_loc_regs_t*);
+  bool cfa_gnu_negative_offset_extended(dwarf_loc_regs_t*);
+
+  using process_func = bool (DwarfCfa::*)(dwarf_loc_regs_t*);
+  constexpr static process_func kCallbackTable[64] = {
+      // 0x00 DW_CFA_nop
+      &DwarfCfa::cfa_nop,
+      // 0x01 DW_CFA_set_loc
+      &DwarfCfa::cfa_set_loc,
+      // 0x02 DW_CFA_advance_loc1
+      &DwarfCfa::cfa_advance_loc,
+      // 0x03 DW_CFA_advance_loc2
+      &DwarfCfa::cfa_advance_loc,
+      // 0x04 DW_CFA_advance_loc4
+      &DwarfCfa::cfa_advance_loc,
+      // 0x05 DW_CFA_offset_extended
+      &DwarfCfa::cfa_offset,
+      // 0x06 DW_CFA_restore_extended
+      &DwarfCfa::cfa_restore,
+      // 0x07 DW_CFA_undefined
+      &DwarfCfa::cfa_undefined,
+      // 0x08 DW_CFA_same_value
+      &DwarfCfa::cfa_same_value,
+      // 0x09 DW_CFA_register
+      &DwarfCfa::cfa_register,
+      // 0x0a DW_CFA_remember_state
+      &DwarfCfa::cfa_remember_state,
+      // 0x0b DW_CFA_restore_state
+      &DwarfCfa::cfa_restore_state,
+      // 0x0c DW_CFA_def_cfa
+      &DwarfCfa::cfa_def_cfa,
+      // 0x0d DW_CFA_def_cfa_register
+      &DwarfCfa::cfa_def_cfa_register,
+      // 0x0e DW_CFA_def_cfa_offset
+      &DwarfCfa::cfa_def_cfa_offset,
+      // 0x0f DW_CFA_def_cfa_expression
+      &DwarfCfa::cfa_def_cfa_expression,
+      // 0x10 DW_CFA_expression
+      &DwarfCfa::cfa_expression,
+      // 0x11 DW_CFA_offset_extended_sf
+      &DwarfCfa::cfa_offset_extended_sf,
+      // 0x12 DW_CFA_def_cfa_sf
+      &DwarfCfa::cfa_def_cfa_sf,
+      // 0x13 DW_CFA_def_cfa_offset_sf
+      &DwarfCfa::cfa_def_cfa_offset_sf,
+      // 0x14 DW_CFA_val_offset
+      &DwarfCfa::cfa_val_offset,
+      // 0x15 DW_CFA_val_offset_sf
+      &DwarfCfa::cfa_val_offset_sf,
+      // 0x16 DW_CFA_val_expression
+      &DwarfCfa::cfa_val_expression,
+      // 0x17 illegal cfa
+      nullptr,
+      // 0x18 illegal cfa
+      nullptr,
+      // 0x19 illegal cfa
+      nullptr,
+      // 0x1a illegal cfa
+      nullptr,
+      // 0x1b illegal cfa
+      nullptr,
+      // 0x1c DW_CFA_lo_user (Treat this as illegal)
+      nullptr,
+      // 0x1d illegal cfa
+      nullptr,
+      // 0x1e illegal cfa
+      nullptr,
+      // 0x1f illegal cfa
+      nullptr,
+      // 0x20 illegal cfa
+      nullptr,
+      // 0x21 illegal cfa
+      nullptr,
+      // 0x22 illegal cfa
+      nullptr,
+      // 0x23 illegal cfa
+      nullptr,
+      // 0x24 illegal cfa
+      nullptr,
+      // 0x25 illegal cfa
+      nullptr,
+      // 0x26 illegal cfa
+      nullptr,
+      // 0x27 illegal cfa
+      nullptr,
+      // 0x28 illegal cfa
+      nullptr,
+      // 0x29 illegal cfa
+      nullptr,
+      // 0x2a illegal cfa
+      nullptr,
+      // 0x2b illegal cfa
+      nullptr,
+      // 0x2c illegal cfa
+      nullptr,
+      // 0x2d DW_CFA_GNU_window_save (Treat this as illegal)
+      nullptr,
+      // 0x2e DW_CFA_GNU_args_size
+      &DwarfCfa::cfa_nop,
+      // 0x2f DW_CFA_GNU_negative_offset_extended
+      &DwarfCfa::cfa_gnu_negative_offset_extended,
+      // 0x30 illegal cfa
+      nullptr,
+      // 0x31 illegal cfa
+      nullptr,
+      // 0x32 illegal cfa
+      nullptr,
+      // 0x33 illegal cfa
+      nullptr,
+      // 0x34 illegal cfa
+      nullptr,
+      // 0x35 illegal cfa
+      nullptr,
+      // 0x36 illegal cfa
+      nullptr,
+      // 0x37 illegal cfa
+      nullptr,
+      // 0x38 illegal cfa
+      nullptr,
+      // 0x39 illegal cfa
+      nullptr,
+      // 0x3a illegal cfa
+      nullptr,
+      // 0x3b illegal cfa
+      nullptr,
+      // 0x3c illegal cfa
+      nullptr,
+      // 0x3d illegal cfa
+      nullptr,
+      // 0x3e illegal cfa
+      nullptr,
+      // 0x3f DW_CFA_hi_user (Treat this as illegal)
+      nullptr,
+  };
+};
+
+#endif  // _LIBUNWINDSTACK_DWARF_CFA_H