[Bug Report] OF flag bit in fflags is not set correctly after fdiv.s instruction

rsd-devel / rsd

RSD: RISC-V Out-of-Order Superscalar Processor

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[Bug Report] OF flag bit in fflags is not set correctly after fdiv.s instruction #87

Closed zhangkanqi closed 4 months ago

zhangkanqi commented 4 months ago

Hi,

There a floating-point arithmetic instruction fdiv.s ft9, ft6, fs10, which ft6=0xfd5d363b, fs10=0x9b068cda and the original value of fflags=0x00000001. But after executing this instruction, fflags remains 0x00000001, not the expected value 0x00000005(Spike does so).

So I wonder if this is a real bug or a problem on floating-point accuracy?

zhangkanqi commented 4 months ago

Updating of fflags isn't implemented yet.