[Bug target/54239] Not able to generate "prefetch" (prefetch read) instruction using -m3dnow or -mprfchw

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54239

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |jakub at gcc dot gnu.org

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-08-13 12:31:52 UTC ---
Both in 4.7 (which is before the prfchw changes) and 4.8 with -m32 -m3dnow and
-m32 -m3dnow -mno-sse I get prefetch + prefetchw insn, which looks ok to me.
-mno-mmx I think disables 3dnow too, so you get no prefetch insns in that case
(which is also fine).  -mprfchw implies the SSE prefetches and PRFCHW CPUID
0x80000001 ecx bit 8 doesn't imply the prefetch insn, just prefetchw, so it is
correct that with -m32 -mprfchw prefetchnta + prefetchw is generated.
So, where exactly do you see a bug?