------- Comment #11 from hjl dot tools at gmail dot com 2008-11-22 15:09 ------- (In reply to comment #10) > We should have -mfma to enable a fused multiply-add instruction that is > available > when enabling either -msse5 or -mavx. -mfma should not itself enable any > of the instruction set enabling features. > > HJ, why did you need -mfma and could not have used -mfused-madd for this? > IMHO -mfma is confusing and should be removed. >
Intel FMA is a separate instruction set with its own feature bit in CPUID. Using -mfused-madd -mavx to enable an instruction set doesn't look appropriate to me. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38201
