Floating point instructions not used

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Floating point instructions not used

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I followed the guideline for adding floating point HW support into the Nios, but when I compile my code, the object dump reveals that the custom instructions (252-255) are not called at all

After genration, the system.h defines this line:# define __ALTERA_NIOS_CUSTOM_INSTR_FLOATING_POINT. No other references to floating point here

The compile option does NOT include any def of FP usage as I would expect: -mcustom_.....

Example of generated code:

float f1,f2

f2 = f1 + 7.56F;

402c4: d1202117 ldw r4,-32636(gp)

402c8: 01503cb4 movhi r5,16626

402cc: 297ae144 addi r5,r5,-5243

402d0: 00405f00 call 405f0 <__addsf3>

402d4: d0a02215 stw r2,-32632(gp)

__addsf3 makes a lot, but no custom 252 for sure

I have tried with NIOS IDE 8.0 and 11.0. The project is built using SOPC at 12.1. The only thing changed was the adding of the floating point into the CPU. No files is supposed to be added?

Jan

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