Does GHC still support x87 floating point math?

Ben Lippmeier benl at
Thu Dec 6 11:16:30 CET 2012

On 06/12/2012, at 12:12 , Johan Tibell wrote:

> I'm currently trying to implement word2Double#. Other such primops
> support both x87 and sse floating point math. Do we still support x87
> fp math? Which compiler flag enables it?

It's on by default unless you use the -sse2 flag. The x87 support is horribly slow though. I don't think anyone would notice if you deleted the x87 code and made SSE the default, especially now that we have the LLVM code generator. SSE has been the way to go for over 10 years now.


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