Which POWER implementations need the HWCAP_DFP check?

Florian Weimer fweimer@redhat.com
Mon May 14 09:42:00 GMT 2018


I think this run-time check is unnecessary on POWER6 and later:

	  double d = (env); \
	  if(GLRO(dl_hwcap) & PPC_FEATURE_HAS_DFP) \
	    asm volatile (".machine push; " \
			  ".machine \"power6\"; " \
			  "mtfsf 0xff,%0,1,0; " \
			  ".machine pop" : : "f" (d)); \
	  else \
	    asm volatile ("mtfsf 0xff,%0" : : "f" (d)); \

In particularly, we do not need it on ppc64le.  Correct?

It's one of the GLIBC_PRIVATE references in libm.so.6, which is why I'm 
asking.

Thanks,
Florian



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