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0d48b43632
The implementation of the fscale instruction returns a NaN exponent unchanged. Fix it to return a quiet NaN when the provided exponent is a signaling NaN. Signed-off-by: Joseph Myers <joseph@codesourcery.com> Message-Id: <alpine.DEB.2.21.2005070043330.18350@digraph.polyomino.org.uk> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
38 lines
794 B
C
38 lines
794 B
C
/* Test fscale instruction. */
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#include <stdint.h>
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#include <stdio.h>
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union u {
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struct { uint64_t sig; uint16_t sign_exp; } s;
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long double ld;
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};
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volatile long double ld_res;
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int isnan_ld(long double x)
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{
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union u tmp = { .ld = x };
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return ((tmp.s.sign_exp & 0x7fff) == 0x7fff &&
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(tmp.s.sig >> 63) != 0 &&
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(tmp.s.sig << 1) != 0);
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}
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int issignaling_ld(long double x)
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{
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union u tmp = { .ld = x };
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return isnan_ld(x) && (tmp.s.sig & UINT64_C(0x4000000000000000)) == 0;
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}
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int main(void)
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{
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int ret = 0;
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__asm__ volatile ("fscale" : "=t" (ld_res) :
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"0" (2.5L), "u" (__builtin_nansl("")));
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if (!isnan_ld(ld_res) || issignaling_ld(ld_res)) {
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printf("FAIL: fscale snan\n");
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ret = 1;
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}
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return ret;
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}
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