diff options
| -rw-r--r-- | target/i386/fpu_helper.c | 4 | ||||
| -rw-r--r-- | tests/tcg/i386/test-i386-fscale.c | 37 |
2 files changed, 41 insertions, 0 deletions
diff --git a/target/i386/fpu_helper.c b/target/i386/fpu_helper.c index 568bd3b..0671de6 100644 --- a/target/i386/fpu_helper.c +++ b/target/i386/fpu_helper.c @@ -970,6 +970,10 @@ void helper_fscale(CPUX86State *env) { if (floatx80_is_any_nan(ST1)) { ST0 = ST1; + if (floatx80_is_signaling_nan(ST0, &env->fp_status)) { + float_raise(float_flag_invalid, &env->fp_status); + ST0 = floatx80_silence_nan(ST0, &env->fp_status); + } } else { int n = floatx80_to_int32_round_to_zero(ST1, &env->fp_status); ST0 = floatx80_scalbn(ST0, n, &env->fp_status); diff --git a/tests/tcg/i386/test-i386-fscale.c b/tests/tcg/i386/test-i386-fscale.c new file mode 100644 index 0000000..aecac51 --- /dev/null +++ b/tests/tcg/i386/test-i386-fscale.c @@ -0,0 +1,37 @@ +/* Test fscale instruction. */ + +#include <stdint.h> +#include <stdio.h> + +union u { + struct { uint64_t sig; uint16_t sign_exp; } s; + long double ld; +}; + +volatile long double ld_res; + +int isnan_ld(long double x) +{ + union u tmp = { .ld = x }; + return ((tmp.s.sign_exp & 0x7fff) == 0x7fff && + (tmp.s.sig >> 63) != 0 && + (tmp.s.sig << 1) != 0); +} + +int issignaling_ld(long double x) +{ + union u tmp = { .ld = x }; + return isnan_ld(x) && (tmp.s.sig & UINT64_C(0x4000000000000000)) == 0; +} + +int main(void) +{ + int ret = 0; + __asm__ volatile ("fscale" : "=t" (ld_res) : + "0" (2.5L), "u" (__builtin_nansl(""))); + if (!isnan_ld(ld_res) || issignaling_ld(ld_res)) { + printf("FAIL: fscale snan\n"); + ret = 1; + } + return ret; +} |