diff options
| author | Richard Henderson <richard.henderson@linaro.org> | 2021-12-17 17:57:16 +0100 |
|---|---|---|
| committer | Cédric Le Goater <clg@kaod.org> | 2021-12-17 17:57:16 +0100 |
| commit | dedbfda765a74c3965c5dd676e64fc3afa15e963 (patch) | |
| tree | 067d5807855f853be8ce2c4a3ba4bd34122e1d26 /target/ppc/fpu_helper.c | |
| parent | 7f87214e3b9f0d562d75f9c7315bfa53b00d29a6 (diff) | |
target/ppc: Add helper for frsqrtes
There is no double-rounding bug here, because the result is
merely an estimate to within 1 part in 32, but perform the
operation with float64r32_div for consistency.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-33-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Diffstat (limited to 'target/ppc/fpu_helper.c')
| -rw-r--r-- | target/ppc/fpu_helper.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c index 4acc557c08..83c8f2556c 100644 --- a/target/ppc/fpu_helper.c +++ b/target/ppc/fpu_helper.c @@ -896,6 +896,25 @@ float64 helper_frsqrte(CPUPPCState *env, float64 arg) return retd; } +/* frsqrtes - frsqrtes. */ +float64 helper_frsqrtes(CPUPPCState *env, float64 arg) +{ + /* "Estimate" the reciprocal with actual division. */ + float64 rets = float64_sqrt(arg, &env->fp_status); + float64 retd = float64r32_div(float64_one, rets, &env->fp_status); + int flags = get_float_exception_flags(&env->fp_status); + + if (unlikely(flags & float_flag_invalid)) { + float_invalid_op_sqrt(env, flags, 1, GETPC()); + } + if (unlikely(flags & float_flag_divbyzero)) { + /* Reciprocal of (square root of) zero. */ + float_zero_divide_excp(env, GETPC()); + } + + return retd; +} + /* fsel - fsel. */ uint64_t helper_fsel(CPUPPCState *env, uint64_t arg1, uint64_t arg2, uint64_t arg3) |