------- Comment #2 from hjl dot tools at gmail dot com 2010-03-01 13:31 -------
This is done on purpose to provide backward compatibility
since vmovq isn't in original x86-64 spec and older assemblers
don't support it. From i386-opc.tbl in binutils:
// These really shouldn't allow for Reg64 (movq is the right mnemonic for
// copying between Reg64/Mem64 and RegXMM/RegMMX, as is mandated by Intel's
// spec). AMD's spec, having been in existence for much longer, failed to
// recognize that and specified movd for 32- and 64-bit operations.
// vmovd really shouldn't allow for 64bit operand (vmovq is the right
// mnemonic for copying between Reg64/Mem64 and RegXMM, as is mandated
// by Intel AVX spec). To avoid extra template in gcc x86 backend and
// support assembler for AMD64, we accept 64bit operand on vmovd so
// that we can use one template for both SSE and AVX instructions.
--
hjl dot tools at gmail dot com changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|ASSIGNED |RESOLVED
Resolution| |WONTFIX
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43215
