z/Architecture Overview

• 64 bit general registers

  • Can be operated upon as 64 or 32 bit entities

#include <stdio.h>

int main(int argc, char **argv)

{

union { long x; int y[2]; } longvar;

longvar.x = -1;

printf("%08X %08X %ld\n",longvar.y[0],longvar.y[1],longvar.x);

__asm__ __volatile__ ("slr %0,%0" : "+d" (longvar.x) : : "cc");

printf("%08X %08X %ld\n",longvar.y[0],longvar.y[1],longvar.x);

__asm__ __volatile__ ("slgr %0,%0" : "+d" (longvar.x) : : "cc");

printf("%08X %08X %ld\n",longvar.y[0],longvar.y[1],longvar.x);

}

FFFFFFFF FFFFFFFF -1

FFFFFFFF 00000000 -4294967296

00000000 00000000 0

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