[LLVMdev] possible PowerPC (32bits) backend bug

Chris Lattner clattner at apple.com
Wed Jun 17 09:15:51 PDT 2009

On Jun 16, 2009, at 11:52 PM, seventh moon wrote:
> At a glance, it looks right. Line 12 is, indeed the "fnmsubs"  
> command, so
> the pattern did work. But look at Line 9. Here we see that the "fmuls"
> also happened! In effect, this means that the fmul happens TWICE.
> That can't be right can it? Unfortunately, I don't have a PPC  
> emulator,
> so I can't run the code and see if it actually works or not.
> But it does not look right to me.

The code is correct.  The mul is being multiply evaluated because  
you're looking at -O0 code, try an equivalent example with -O2 or  


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