[LLVMdev] detailed comparison of generated code size for LLVM and other compilers

Anton Korobeynikov anton at korobeynikov.info
Tue Dec 15 01:54:03 PST 2009

> This might be a very stupid question, but can we not choose to disable
> SSE code generating in a case-by-case basis, even when those
> optimizations are turned on?
> In that case, I imagine that 1.0 is considered double and would
> normally fill one or two registers, thus easy enough to return it via
> registers. Unless, of course, the ABI mandates that SSE is
> all-or-nothing...
ABI does not mandate the usage of SSE or x86 FP math exclusively.
It just requires the FP values to be *always* returned via FP stack.

With best regards, Anton Korobeynikov
Faculty of Mathematics and Mechanics, Saint Petersburg State University

More information about the llvm-dev mailing list