Assembler Floating point operation
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I'm using Assembler with AT&t syntax under linux.
I need to divide and multiply 3 numbers (a,b,c).
The operation is likely a/b*c,i've tried using idiv and imul istruction but of course those works on integer numbers so i'm getting total inaccurate results from them.
I also tried to use fidiv and fimul istruction to use float in calculation but i'm getting totally wrong results.So probably i'm doing the operation on the wrong registers.
Can someone please do me an example on how to use fidiv/fimul under AT&T? Wich registers do those istructions use?

Thanks in advance.