diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c index 44f3fed17d..5af5241ab0 100644 --- a/target/ppc/fpu_helper.c +++ b/target/ppc/fpu_helper.c @@ -879,18 +879,27 @@ float64 helper_fsqrt(CPUPPCState *env, float64 arg) } /* fre - fre. */ -uint64_t helper_fre(CPUPPCState *env, uint64_t arg) +float64 helper_fre(CPUPPCState *env, float64 arg) { - CPU_DoubleU farg; + /* "Estimate" the reciprocal with actual division. */ + float64 ret = float64_div(float64_one, arg, &env->fp_status); + int status = get_float_exception_flags(&env->fp_status); - farg.ll = arg; - - if (unlikely(float64_is_signaling_nan(farg.d, &env->fp_status))) { - /* sNaN reciprocal */ - float_invalid_op_excp(env, POWERPC_EXCP_FP_VXSNAN, 1); + if (unlikely(status)) { + if (status & float_flag_invalid) { + if (float64_is_signaling_nan(arg, &env->fp_status)) { + /* sNaN reciprocal */ + float_invalid_op_excp(env, POWERPC_EXCP_FP_VXSNAN, 1); + } + } + if (status & float_flag_divbyzero) { + float_zero_divide_excp(env, GETPC()); + /* For FPSCR.ZE == 0, the result is 1/2. */ + ret = float64_set_sign(float64_half, float64_is_neg(arg)); + } } - farg.d = float64_div(float64_one, farg.d, &env->fp_status); - return farg.d; + + return ret; } /* fres - fres. */ @@ -913,27 +922,30 @@ uint64_t helper_fres(CPUPPCState *env, uint64_t arg) } /* frsqrte - frsqrte. */ -uint64_t helper_frsqrte(CPUPPCState *env, uint64_t arg) +float64 helper_frsqrte(CPUPPCState *env, float64 arg) { - CPU_DoubleU farg; + /* "Estimate" the reciprocal with actual division. */ + float64 rets = float64_sqrt(arg, &env->fp_status); + float64 retd = float64_div(float64_one, rets, &env->fp_status); + int status = get_float_exception_flags(&env->fp_status); - farg.ll = arg; - - if (unlikely(float64_is_any_nan(farg.d))) { - if (unlikely(float64_is_signaling_nan(farg.d, &env->fp_status))) { - /* sNaN reciprocal square root */ - float_invalid_op_excp(env, POWERPC_EXCP_FP_VXSNAN, 1); - farg.ll = float64_snan_to_qnan(farg.ll); + if (unlikely(status)) { + if (status & float_flag_invalid) { + if (float64_is_signaling_nan(arg, &env->fp_status)) { + /* sNaN reciprocal */ + float_invalid_op_excp(env, POWERPC_EXCP_FP_VXSNAN, 1); + } else { + /* Square root of a negative nonzero number */ + float_invalid_op_excp(env, POWERPC_EXCP_FP_VXSQRT, 1); + } + } + if (status & float_flag_divbyzero) { + /* Reciprocal of (square root of) zero. */ + float_zero_divide_excp(env, GETPC()); } - } else if (unlikely(float64_is_neg(farg.d) && !float64_is_zero(farg.d))) { - /* Reciprocal square root of a negative nonzero number */ - farg.ll = float_invalid_op_excp(env, POWERPC_EXCP_FP_VXSQRT, 1); - } else { - farg.d = float64_sqrt(farg.d, &env->fp_status); - farg.d = float64_div(float64_one, farg.d, &env->fp_status); } - return farg.ll; + return retd; } /* fsel - fsel. */