A program dynamic loading method, device and storage medium

Abstract

The invention provides a program dynamic loading method, a program dynamic loading device and a storage medium. The method comprises the following steps: compiling: employing compiling parameters to compile a source code into an address-independent program file; performing relocation preprocessing: calculating a relocation address and a logic address needing to be filled into the relocation address for the program file according to the relocation item type after compiling is completed, and downloading the preprocessed program file to any position of FLASH; and loading: loading data required byprogram operation based on the calculated relocation address and the logic address needing to be filled into the relocation address, and directly operating the program file in FLASH. The method avoids the process of copying the APP file from the FLASH to the RAM, increases the application starting speed, reduces the program size, does not limit the application starting address, does not limit theapplication storage address, realizes direct operation of the APP on FLASH, is suitable for being operated on small devices such as an MCU, and supports debugging of the dynamically loaded APP.

Description

technical field [0001] The invention relates to the technical field of computer program compilation, in particular to a program dynamic loading method, device and storage medium. Background technique [0002] There are mainly two technical solutions for the dynamic loading of application programs in existing operating systems: [0003] The first way is to use the overall loading method: first compile and link the application program with a fixed running address; then when the application program is dynamically loaded, copy the application executable file as a whole to the memory area at the specified address; finally execute it from the memory code. [0004] The second way is to use the dynamic link file method: first use gcc -shared -fPIC to compile the address-independent code; then dynamically load it to the address 0x00000000; at runtime, use PC + offset to obtain the internal data of the module, and PC + offset Get the GOT table address by measuring, and then get the ...

AI Technical Summary

Problems solved by technology

[0006] In the first method, because the loading process needs to copy the APP executable file to RAM, the loading speed is slow

In the second method, the code segment and data segment must be loaded into the memory as a whole and relocated. Since the APP executable file needs to be copied to RAM for execution, it is impossible to load more complex APPs on an MCU with a shortage of RAM. , when the APP executable file is large, due to memory limitations, dynamic loading cannot be realized. There are many relocation methods in the original ELF file. The loader needs to perform corresponding searches and calculations according to different methods, and then modify The data corresponding to the address in the memory has low relocation efficiency. In addition, because there is a large amount of runtime-independent information in the ELF file generated by compilation, some are related to loading data, and some are related to debugging, resulting in a large ELF size and occupying A lot of FLASH space

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