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/* { dg-do run } */
/* { dg-options "-O2 -fdump-rtl-combine --save-temps" } */
/* Test that we don't generate BSL when in DImode with values in integer
registers, and do generate it where we have values in floating-point
registers. This is useful, as it allows us to avoid register moves
in the general case.
We want:
eor x0, x0, x1
and x0, x0, x2
eor x0, x0, x1
ret
Rather than:
fmov d2, x0
fmov d0, x2
fmov d1, x1
bsl v0.8b, v2.8b, v1.8b
fmov x0, d0
ret */
extern void abort (void);
unsigned long long __attribute__ ((noinline))
foo (unsigned long long a, unsigned long long b, unsigned long long c)
{
return ((a ^ b) & c) ^ b;
}
unsigned long long __attribute__ ((noinline))
foo2 (unsigned long long a, unsigned long long b, unsigned long long c)
{
return ((a ^ b) & c) ^ a;
}
#define force_simd(V1) asm volatile ("mov %d0, %1.d[0]" \
: "=w"(V1) \
: "w"(V1) \
: /* No clobbers */);
unsigned long long __attribute__ ((noinline))
bar (unsigned long long a, unsigned long long b, unsigned long long c)
{
force_simd (a);
force_simd (b);
force_simd (c);
c = ((a ^ b) & c) ^ b;
force_simd (c);
return c;
}
unsigned long long __attribute__ ((noinline))
bar2 (unsigned long long a, unsigned long long b, unsigned long long c)
{
force_simd (a);
force_simd (b);
force_simd (c);
c = ((a ^ b) & c) ^ a;
force_simd (c);
return c;
}
int
main (int argc, char** argv)
{
unsigned long long a = 0x0123456789abcdefULL;
unsigned long long b = 0xfedcba9876543210ULL;
unsigned long long c = 0xaabbccddeeff7777ULL;
if (foo (a, b, c) != bar (a, b, c))
abort ();
if (foo2 (a, b, c) != bar2 (a, b, c))
abort ();
return 0;
}
/* 2 BSL, 6 FMOV (to floating-point registers), and 2 FMOV (to general
purpose registers) for the "bar" tests, which should still use BSL. */
/* { dg-final { scan-assembler-times "bsl\tv\[0-9\]" 2 } } */
/* { dg-final { scan-assembler-times "fmov\td\[0-9\]" 6 } } */
/* { dg-final { scan-assembler-times "fmov\tx\[0-9\]" 2 } } */
/* { dg-final { scan-assembler-not "bif\tv\[0-9\]" } } */
/* { dg-final { scan-assembler-not "bit\tv\[0-9\]" } } */
/* We always match the idiom during combine. */
/* { dg-final { scan-rtl-dump-times "aarch64_simd_bsldi_internal" 2 "combine" } } */
/* { dg-final { scan-rtl-dump-times "aarch64_simd_bsldi_alt" 2 "combine" } } */
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