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Altera_Forum
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19 years ago

How to use fpu custom instruction ?

I work on a NIOSII with a fpu provided by Altera (taking into account +, -, *, and / operations on float). So when I write C code : A + B (where A and B are float type), assembler code use custom ins...
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Altera_Forum
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19 years ago

I looked through the GCC source and it indeed looks like a bug in the NIOS compiler.

Search for 'nios2_output_fpu_insn_cmps' in

C:\altera\kits\nios2_60\bin\nios2-gnutools\src

Note that it is never called or referenced by any of the code. I don't know much aboug GCC, but that looks like a pretty obvious problem. Want to report this to the Nios crew? If you do make a report, also report the bug of the optimizer not using the FPU. That's a pretty seriously bug.