loop-1.c

来自「Mac OS X 10.4.9 for x86 Source Code gcc」· C语言 代码 · 共 37 行

/* { dg-do compile } */
/* { dg-options "-O1 -ftree-loop-ivcanon -funroll-loops -fdump-tree-ivcanon-details -fdump-tree-cunroll-details -fdump-tree-vars" } */

/* On 31-bit S/390 the function address will be stored (once) in the literal pool,
   so scan-assembler-times "foo" will return 1 even if the loop is fully unrolled.
   -msmall-exec avoids this by enabling a call instruction with immediate operand.  */
/* { dg-options "-O1 -ftree-loop-ivcanon -funroll-loops -fdump-tree-ivcanon-details -fdump-tree-cunroll-details -fdump-tree-vars -msmall-exec" { target s390-*-* } } */

/* On Darwin, we call extern functions via a stub in PIC mode which is default and
   the stub is named after the function.  To avoid this we use -static to go out
   of PIC mode.  */
/* { dg-options "-O1 -ftree-loop-ivcanon -funroll-loops -fdump-tree-ivcanon-details -fdump-tree-cunroll-details -fdump-tree-vars -static" { target *-*-darwin* } } */

void xxx(void)
{
  int x = 45;

  while (x >>= 1)
    foo ();
}

/* We should be able to find out that the loop iterates four times and unroll it completely.  */

/* { dg-final { scan-tree-dump-times "Added canonical iv to loop 1, 4 iterations" 1 "ivcanon"} } */
/* { dg-final { scan-tree-dump-times "Unrolled loop 1 completely" 1 "cunroll"} } */
/* { dg-final { scan-tree-dump-times "foo" 5 "vars"} } */

/* Because hppa and ia64 targets include an external declaration for foo as
   well as the calls we need to look for something more specific then just
   foo in order to count only the calls and not the declaration.  */

/* { dg-final { scan-assembler-times "foo" 5 { xfail hppa*-*-* ia64*-*-* } } } */
/* { dg-final { scan-assembler-times "foo,%r" 5 { target hppa*-*-* } } } */
/* { dg-final { scan-assembler-times "= foo"  5 { target ia64*-*-* } } } */