Below is a quick idapython snippet to find specific mnemonics you may want to look for. either replace " if (mnem == 'fldcw'):" with what you're looking for, or add more to the logic to search for multiple mnemonics.
Disclaimer: a friend and I coded this VERY quickly and there may be errors, its definitely not "production" quality, probably best to use as a reference or something to build upon ;)
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mnemonics = dict()
for seg_ea in Segments():
for head in Heads(seg_ea, SegEnd(seg_ea)):
if isCode(GetFlags(head)):
mnem = GetMnem(head)
if (mnem == 'fldcw'):
print 'fldcw at: 0x%x' % head
mnemonics[mnem] = mnemonics.get(mnem,0)+1
