_asm and or one of those pseudo-assembler/library routines like __tr() for
more machine instructions.

Yes, overhead is definitely a negative for calls, especially if (like some
of us) you have not exactly gotten around to embracing XPLINK.

Charles

-----Original Message-----
From: IBM Mainframe Discussion List [mailto:[email protected]] On
Behalf Of David Crayford
Sent: Tuesday, July 23, 2013 7:59 PM
To: [email protected]
Subject: Re: Is there a "reverse bits" hardware instruction?

There's a RLLG instruction to rotate the bits in a 64-bit integer. I know
that you want to call such a routine from C/C++. If you need to write
ffs64() in assembler you may find the linkage overhead of calling the
routine is far greater than a slower implementation that has been inlined.
It's about time IBM enhanced C/C++ to support __asm for non-Metal/C
compiles.

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