GCC MIPS-32 Calling Conventions / Stack Frame Definition

Question

There appears to be no definitive standardized stack frame and C language calling conventions (register usage and such) for the MIPS-32 Processor Architecture. That is, it appears to be completely up to the assembler/compiler tool chain to define their own stack frame and calling conventions. I've struggled to find a definitive reference of what conventions the GCC compiler uses for MIPS-32 instruction set. I'm specially using GCC cross-compiler on Cygwin that targets a MIPS-32 core being used in an embedded environment on the eCos open source kernel.

Any references to definitive documentation about GCC for MIPS-32 in this area would be appreciated.

Answer 1

You are right, this is a bit of a mess and is poorly documented. I would recommend:

• http://math-atlas.sourceforge.net/devel/assembly/mipsabi32.pdf
• "See MIPS Run" by Dominic Sweetman
• Examining disassembled code generated by the compiler to check for discrepancies with the above references.

Answer 2

Does this reference on MIPS EABI for RedHat Linux help?

Answer 3

I'm not into MIPS, but maybe this MIPS ABI History reference might help.