On Mon, Aug 12, 2024 at 08:48:22AM -0500, Peter Bergner wrote: > On 8/11/24 9:42 PM, Kewen.Lin wrote: > > One difference with this change is that previously users specify -mno-vsx to > > disable all vector insns (both VMX and VSX) on Power[89], now they should > > use -mno-altivec for that purpose. I think it's better as it matches the > > behaviors on Power7? > > I hope there are no users out there thinking that -mno-vsx disables all > vector, since that just has never been true. The -mno-altivec option has > always been the correct method for disabling all vector type instructions > (for -mcpu=XXX cpus that support vector).
Yup. And "TARGET_ALTIVEC" does not mean just the old AltiVec insns, but everything gated of off / endabled by MSR[VEC]. We probably should have called it TARGET_VEC instead. And we still can, bit by bit even. This is handy for people reading the ISA, like most of us: the instruction descriptions talk about MSR[VEC] and MSR[VSX] all over the place. And people will less easily understand this as being about just the old insns! Segher
