我正在使用ARM-GCC 4.7.4编译Cortex-M4的代码。对于我们的调试工具,我需要以人类可读格式(例如.txt)了解所有变量的名称、类型和地址。地图文件提供了大部分信息,但不包括以下结构内容:
typedef struct { float32_t Ref; // Input: Reference Value
float32_t Fdb; // Variable: Feedback Value
float32_t Err; // Input: Control Error
float32_t Kp; // Parameter: Gain of the Proportional Part
float32_t Up; // Output: Output of Proportional Part
float32_t Ki; // Parameter: Gain of the Integral Part
float32_t Ui; // Output: Output of the Integral Part
float32_t OutPreSat; // Output: Not saturated Output
float32_t OutMax; // Parameter: Maximum Output
float32_t OutMin; // Parameter: Minimum Output
float32_t Out; // Output: Saturated Output
} PI_REG;
PI_REG BU_Uctrl_Udc_PI_Reg = BU_UCTRL_UDC_PI_REG_INIT;
因此,我尝试使用nm、readelf和objdump等工具来获取以dwarf-2格式编译并带有-g3参数的.elf文件的信息。只有通过objdump,我才能找到我要查找的信息:
objdump –Wi myfile.elf >symbols.txt
typedef PI_REG的以下信息可以在symbols.txt文件中找到:
<1><38883>: Abbrev Number: 2 (DW_TAG_base_type)
<38884> DW_AT_byte_size : 4
<38885> DW_AT_encoding : 4 (float)
<38886> DW_AT_name : (indirect string, offset: 0x2c63e): float
<1><38891>: Abbrev Number: 11 (DW_TAG_typedef)
<38892> DW_AT_name : (indirect string, offset: 0xb336d): float32_t
<38896> DW_AT_decl_file : 4
<38897> DW_AT_decl_line : 370
<38899> DW_AT_type : <0x38883>
<1><390d7>: Abbrev Number: 14 (DW_TAG_structure_type)
<390d8> DW_AT_byte_size : 44
<390d9> DW_AT_decl_file : 6
<390da> DW_AT_decl_line : 26
<390db> DW_AT_sibling : <0x39176>
<2><390df>: Abbrev Number: 16 (DW_TAG_member)
<390e0> DW_AT_name : Ref
<390e4> DW_AT_decl_file : 6
<390e5> DW_AT_decl_line : 26
<390e6> DW_AT_type : <0x38891>
<390ea> DW_AT_data_member_location: 2 byte block: 23 0 (DW_OP_plus_uconst: 0)
<2><390ed>: Abbrev Number: 16 (DW_TAG_member)
<390ee> DW_AT_name : Fdb
<390f2> DW_AT_decl_file : 6
<390f3> DW_AT_decl_line : 27
<390f4> DW_AT_type : <0x38891>
<390f8> DW_AT_data_member_location: 2 byte block: 23 4 (DW_OP_plus_uconst: 4)
[省略具有偏移量6-32的结构成员]
<2><39159>: Abbrev Number: 15 (DW_TAG_member)
<3915a> DW_AT_name : (indirect string, offset: 0xc1d9a): OutMin
<3915e> DW_AT_decl_file : 6
<3915f> DW_AT_decl_line : 35
<39160> DW_AT_type : <0x38891>
<39164> DW_AT_data_member_location: 2 byte block: 23 24 (DW_OP_plus_uconst: 36)
<2><39167>: Abbrev Number: 16 (DW_TAG_member)
<39168> DW_AT_name : Out
<3916c> DW_AT_decl_file : 6
<3916d> DW_AT_decl_line : 36
<3916e> DW_AT_type : <0x38891>
<39172> DW_AT_data_member_location: 2 byte block: 23 28 (DW_OP_plus_uconst: 40)
<1><39176>: Abbrev Number: 3 (DW_TAG_typedef)
<39177> DW_AT_name : (indirect string, offset: 0xc00d0): PI_REG
<3917b> DW_AT_decl_file : 6
<3917c> DW_AT_decl_line : 37
<3917d> DW_AT_type : <0x390d7>
<1><3c348>: Abbrev Number: 29 (DW_TAG_variable)
<3c349> DW_AT_name : (indirect string, offset: 0xc3ece): BU_Uctrl_Udc_PI_Reg
<3c34d> DW_AT_decl_file : 1
<3c34e> DW_AT_decl_line : 40
<3c34f> DW_AT_type : <0x39176>
<3c353> DW_AT_external : 1
<3c354> DW_AT_location : 5 byte block: 3 fc 67 0 20 (DW_OP_addr: 200067fc)
如果我想获取有关变量的信息,例如结构BU_Uctrl_Udc_PI_Reg,我需要执行以下操作:
Find an entry called “DW_TAG_variable” and gather following information:
------------------------------------------------------------------------
- DW_AT_name: The name is BU_Uctrl_Udc_PI_Reg
- DW_OP_addr: Base address is 200067fc
- DW_AT_type: The data type can be found at line 39176
Search line 39176 and gather following information:
-----------------------------------------------------
- It is a typedef (DW_TAG_typedef)
- DW_AT_name: The typedef name is PI_REG
- DW_AT_type: The definition can be found at line 390d7
Search line 390d7 and gather following information:
---------------------------------------------------
- It is a structure (DW_TAG_structure_type)
- DW_AT_byte_size: It is 44 bytes wide
Search the structure Members in upcoming lines until 44 bytes are reached:
--------------------------------------------------------
1. Member (DW_TAG_member):
- DW_AT_name: Ref
- DW_AT_data_member_location: 200067fc + 0
- DW_AT_type: The data type can be found at line 38891:
- DW_TAG_typedef: float32_t
- DW_AT_type: The data type can be found at line 38883:
- DW_TAG_base_type: float
- DW_AT_byte_size: 4 bytes
2. Member (DW_TAG_member):
- DW_AT_name: Fdb
- DW_AT_data_member_location: 200067fc + 4
- DW_AT_type: The data type can be found at line 38891:
- DW_TAG_typedef: float32_t
- DW_AT_type: The data type can be found at line 38883:
- DW_TAG_base_type: float
- DW_AT_byte_size: 4 bytes
[left out Members 3-9]
10. Member (DW_TAG_member):
- DW_AT_name: OutMin
- DW_AT_data_member_location: 200067fc + 36
- DW_AT_type: The data type can be found at line 38891:
- DW_TAG_typedef: float32_t
- DW_AT_type: The data type can be found at line 38883:
- DW_TAG_base_type: float
- DW_AT_byte_size: 4 bytes
11. Member (DW_TAG_member):
- DW_AT_name: Out
- DW_AT_data_member_location: 200067fc + 40
- DW_AT_type: The data type can be found at line 38891:
- DW_TAG_typedef: float32_t
- DW_AT_type: The data type can be found at line 38883:
- DW_TAG_base_type: float
- DW_AT_byte_size: 4 bytes
坦率地说,一个自动收集上述信息的脚本文件将比我的应用程序更加复杂。另外,我必须承认我不真正知道如何编写这样的脚本。是否有更简单的方法来获取此类型的信息?可能有一些objdump参数可以帮助我完成这项工作,尽管我认为我已经尝试了所有相关的参数?或者是否存在能够完成这项工作的工具?最终我需要像这样的表格(此外,拥有所有枚举类型也很好,当然也可以在.elf文件中找到):
0x200067fc float BU_Uctrl_Udc_PI_Reg.Ref
0x20006800 float BU_Uctrl_Udc_PI_Reg.Fdb
[…]
0x20006832 float BU_Uctrl_Udc_PI_Reg.OutMin
0x20006836 float BU_Uctrl_Udc_PI_Reg.Out
工具Fromelf (包含在Keil µVision中)使用参数--text可以准确地生成这样的表格,但不幸的是我不能使用它,因为它似乎需要使用Arm Compiler Toolchain编译的.elf或在本例中称为.axf文件才能正常工作。此外还存在许可问题。
感谢任何提示。
-S
),然后使用sed
命令处理以生成偏移列表。 - artless noise