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The helper functions for FPATAN, FYL2XP1, and FYL2X incorrectly check for signaling NaN before checking for invalid encodings. This causes pseudo-NaNs to be treated as valid signaling NaNs and silenced, rather than being rejected as unsupported formats. Reorder the checks to test floatx80_invalid_encoding before floatx80_is_signaling_nan, matching the correct behavior already implemented in helper_fscale. Signed-off-by: Max Chou Reviewed-by: Richard Henderson Reviewed-by: Chao Liu Signed-off-by: Richard Henderson Message-ID: <20260204051756.667397-5-max.chou@sifive.com> --- target/i386/tcg/fpu_helper.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) diff --git a/target/i386/tcg/fpu_helper.c b/target/i386/tcg/fpu_helper.c index b3b23823fd..37c83ded38 100644 --- a/target/i386/tcg/fpu_helper.c +++ b/target/i386/tcg/fpu_helper.c @@ -1377,16 +1377,16 @@ void helper_fpatan(CPUX86State *env) int32_t arg1_exp =3D extractFloatx80Exp(ST1); bool arg1_sign =3D extractFloatx80Sign(ST1); =20 - if (floatx80_is_signaling_nan(ST0, &env->fp_status)) { + if (floatx80_invalid_encoding(ST0, &env->fp_status) || + floatx80_invalid_encoding(ST1, &env->fp_status)) { + float_raise(float_flag_invalid, &env->fp_status); + ST1 =3D floatx80_default_nan(&env->fp_status); + } else if (floatx80_is_signaling_nan(ST0, &env->fp_status)) { float_raise(float_flag_invalid, &env->fp_status); ST1 =3D floatx80_silence_nan(ST0, &env->fp_status); } else if (floatx80_is_signaling_nan(ST1, &env->fp_status)) { float_raise(float_flag_invalid, &env->fp_status); ST1 =3D floatx80_silence_nan(ST1, &env->fp_status); - } else if (floatx80_invalid_encoding(ST0, &env->fp_status) || - floatx80_invalid_encoding(ST1, &env->fp_status)) { - float_raise(float_flag_invalid, &env->fp_status); - ST1 =3D floatx80_default_nan(&env->fp_status); } else if (floatx80_is_any_nan(ST0)) { ST1 =3D ST0; } else if (floatx80_is_any_nan(ST1)) { @@ -2061,16 +2061,16 @@ void helper_fyl2xp1(CPUX86State *env) int32_t arg1_exp =3D extractFloatx80Exp(ST1); bool arg1_sign =3D extractFloatx80Sign(ST1); =20 - if (floatx80_is_signaling_nan(ST0, &env->fp_status)) { + if (floatx80_invalid_encoding(ST0, &env->fp_status) || + floatx80_invalid_encoding(ST1, &env->fp_status)) { + float_raise(float_flag_invalid, &env->fp_status); + ST1 =3D floatx80_default_nan(&env->fp_status); + } else if (floatx80_is_signaling_nan(ST0, &env->fp_status)) { float_raise(float_flag_invalid, &env->fp_status); ST1 =3D floatx80_silence_nan(ST0, &env->fp_status); } else if (floatx80_is_signaling_nan(ST1, &env->fp_status)) { float_raise(float_flag_invalid, &env->fp_status); ST1 =3D floatx80_silence_nan(ST1, &env->fp_status); - } else if (floatx80_invalid_encoding(ST0, &env->fp_status) || - floatx80_invalid_encoding(ST1, &env->fp_status)) { - float_raise(float_flag_invalid, &env->fp_status); - ST1 =3D floatx80_default_nan(&env->fp_status); } else if (floatx80_is_any_nan(ST0)) { ST1 =3D ST0; } else if (floatx80_is_any_nan(ST1)) { @@ -2159,16 +2159,16 @@ void helper_fyl2x(CPUX86State *env) int32_t arg1_exp =3D extractFloatx80Exp(ST1); bool arg1_sign =3D extractFloatx80Sign(ST1); =20 - if (floatx80_is_signaling_nan(ST0, &env->fp_status)) { + if (floatx80_invalid_encoding(ST0, &env->fp_status) || + floatx80_invalid_encoding(ST1, &env->fp_status)) { + float_raise(float_flag_invalid, &env->fp_status); + ST1 =3D floatx80_default_nan(&env->fp_status); + } else if (floatx80_is_signaling_nan(ST0, &env->fp_status)) { float_raise(float_flag_invalid, &env->fp_status); ST1 =3D floatx80_silence_nan(ST0, &env->fp_status); } else if (floatx80_is_signaling_nan(ST1, &env->fp_status)) { float_raise(float_flag_invalid, &env->fp_status); ST1 =3D floatx80_silence_nan(ST1, &env->fp_status); - } else if (floatx80_invalid_encoding(ST0, &env->fp_status) || - floatx80_invalid_encoding(ST1, &env->fp_status)) { - float_raise(float_flag_invalid, &env->fp_status); - ST1 =3D floatx80_default_nan(&env->fp_status); } else if (floatx80_is_any_nan(ST0)) { ST1 =3D ST0; } else if (floatx80_is_any_nan(ST1)) { --=20 2.43.0