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Altera_Forum
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15 years ago

Do I need to set compile flag for Hardware Floating Point Custom Instruction Divider?

I added the hardware FPU into SOPC including divider. In the public.mk file the compile flag is: ALT_CFLAGS += -mcustom-fpu-cfg=60-1 ALT_LDFLAGS += -mcustom-fpu-cfg=60-1 So I have to set ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

I've just look at the gcc sources and done some quick tests (gcc3).

Setting -mcustom-cpu-cfg=60-2 or 73-2 does cause a custom instruction to be generated for divide, 60-1 doesn't.

Adding -mcustom-fdivs=nnn is also enough.