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kit
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ibit_long_shift_const.c (617B)

      1 /* 64-bit shifts by a constant amount on `long`/`unsigned long`. Exercises the
      2  * 64-bit immediate shift forms (LSL/LSR/ASR via the x-register UBFM/SBFM).
      3  * volatile defeats folding.
      4  *   u = 0x15 (21):  u << 1 = 42 (logical left)
      5  *   v = 0x150 (336): v >> 3 = 42 (logical right, unsigned)
      6  *   s = -336:        s >> 3 = -42 (arithmetic right, signed)
      7  *   42 + 42 + (-42) = 42. */
      8 int test_main(void) {
      9   volatile unsigned long u = 0x15;
     10   volatile unsigned long v = 0x150;
     11   volatile long s = -336;
     12   long lsl = (long)(u << 1);
     13   long lsr = (long)(v >> 3);
     14   long asr = s >> 3;
     15   return (int)(lsl + lsr + asr);
     16 }