Binary, do you use Hard-Float or Soft-Float?

Many cost-sensitive ARM Cortex-M devices like the M0+ do not have a hardware floating point unit, and some like the M4 only has an optional single-precision floating point unit (FPU). As outlined in “Be aware: Floating Point Operations on ARM Cortex-M4F“, using floating point operations without a hardware unit can be costly.

Looking at the disassembly for sure will tell you if the hardware is handling the float or double operation or not:

Disassembly showing runtime routines

But who wants check the all the disassembly? With the GNU tools there is an easier way: readelf.

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Loading Multiple (Binary) Files with GDB

A typical debugging session involves just one ELF/Dwarf binary or executable. But what if I need to program multiple binary files with gdb? Things like loading both the bootloader and the application binary? Or I have a an on-chip file system or data section I need to program?

In this article I show how I can use gdb to load and program extra data, like a binary (.bin) file, both using command line interface and using an IDE.

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