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target/ppc: change xs[n]madd[am]sp to use float64r32_muladd
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Change VSX Scalar Multiply-Add/Subtract Type-A/M Single Precision
helpers to use float64r32_muladd. This method should correctly handle
all rounding modes, so the workaround for float_round_nearest_even can
be dropped.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Message-Id: <20220304165417.1981159-3-matheus.ferst@eldorado.org.br>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
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@mferst @legoater
mferst authored and legoater committed Mar 5, 2022
1 parent d21939c commit 4e4b5a3
Showing 1 changed file with 20 additions and 38 deletions.
58 changes: 20 additions & 38 deletions target/ppc/fpu_helper.c
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Expand Up @@ -2156,9 +2156,8 @@ VSX_TSQRT(xvtsqrtsp, 4, float32, VsrW(i), -126, 23)
* maddflgs - flags for the float*muladd routine that control the
* various forms (madd, msub, nmadd, nmsub)
* sfprf - set FPRF
* r2sp - round intermediate double precision result to single precision
*/
#define VSX_MADD(op, nels, tp, fld, maddflgs, sfprf, r2sp) \
#define VSX_MADD(op, nels, tp, fld, maddflgs, sfprf) \
void helper_##op(CPUPPCState *env, ppc_vsr_t *xt, \
ppc_vsr_t *s1, ppc_vsr_t *s2, ppc_vsr_t *s3) \
{ \
Expand All @@ -2170,31 +2169,14 @@ void helper_##op(CPUPPCState *env, ppc_vsr_t *xt, \
for (i = 0; i < nels; i++) { \
float_status tstat = env->fp_status; \
set_float_exception_flags(0, &tstat); \
if (r2sp && (tstat.float_rounding_mode == float_round_nearest_even)) {\
/* \
* Avoid double rounding errors by rounding the intermediate \
* result to odd. \
*/ \
set_float_rounding_mode(float_round_to_zero, &tstat); \
t.fld = tp##_muladd(s1->fld, s3->fld, s2->fld, \
maddflgs, &tstat); \
t.fld |= (get_float_exception_flags(&tstat) & \
float_flag_inexact) != 0; \
} else { \
t.fld = tp##_muladd(s1->fld, s3->fld, s2->fld, \
maddflgs, &tstat); \
} \
t.fld = tp##_muladd(s1->fld, s3->fld, s2->fld, maddflgs, &tstat); \
env->fp_status.float_exception_flags |= tstat.float_exception_flags; \
\
if (unlikely(tstat.float_exception_flags & float_flag_invalid)) { \
float_invalid_op_madd(env, tstat.float_exception_flags, \
sfprf, GETPC()); \
} \
\
if (r2sp) { \
t.fld = do_frsp(env, t.fld, GETPC()); \
} \
\
if (sfprf) { \
helper_compute_fprf_float64(env, t.fld); \
} \
Expand All @@ -2203,24 +2185,24 @@ void helper_##op(CPUPPCState *env, ppc_vsr_t *xt, \
do_float_check_status(env, GETPC()); \
}

VSX_MADD(XSMADDDP, 1, float64, VsrD(0), MADD_FLGS, 1, 0)
VSX_MADD(XSMSUBDP, 1, float64, VsrD(0), MSUB_FLGS, 1, 0)
VSX_MADD(XSNMADDDP, 1, float64, VsrD(0), NMADD_FLGS, 1, 0)
VSX_MADD(XSNMSUBDP, 1, float64, VsrD(0), NMSUB_FLGS, 1, 0)
VSX_MADD(XSMADDSP, 1, float64, VsrD(0), MADD_FLGS, 1, 1)
VSX_MADD(XSMSUBSP, 1, float64, VsrD(0), MSUB_FLGS, 1, 1)
VSX_MADD(XSNMADDSP, 1, float64, VsrD(0), NMADD_FLGS, 1, 1)
VSX_MADD(XSNMSUBSP, 1, float64, VsrD(0), NMSUB_FLGS, 1, 1)

VSX_MADD(xvmadddp, 2, float64, VsrD(i), MADD_FLGS, 0, 0)
VSX_MADD(xvmsubdp, 2, float64, VsrD(i), MSUB_FLGS, 0, 0)
VSX_MADD(xvnmadddp, 2, float64, VsrD(i), NMADD_FLGS, 0, 0)
VSX_MADD(xvnmsubdp, 2, float64, VsrD(i), NMSUB_FLGS, 0, 0)

VSX_MADD(xvmaddsp, 4, float32, VsrW(i), MADD_FLGS, 0, 0)
VSX_MADD(xvmsubsp, 4, float32, VsrW(i), MSUB_FLGS, 0, 0)
VSX_MADD(xvnmaddsp, 4, float32, VsrW(i), NMADD_FLGS, 0, 0)
VSX_MADD(xvnmsubsp, 4, float32, VsrW(i), NMSUB_FLGS, 0, 0)
VSX_MADD(XSMADDDP, 1, float64, VsrD(0), MADD_FLGS, 1)
VSX_MADD(XSMSUBDP, 1, float64, VsrD(0), MSUB_FLGS, 1)
VSX_MADD(XSNMADDDP, 1, float64, VsrD(0), NMADD_FLGS, 1)
VSX_MADD(XSNMSUBDP, 1, float64, VsrD(0), NMSUB_FLGS, 1)
VSX_MADD(XSMADDSP, 1, float64r32, VsrD(0), MADD_FLGS, 1)
VSX_MADD(XSMSUBSP, 1, float64r32, VsrD(0), MSUB_FLGS, 1)
VSX_MADD(XSNMADDSP, 1, float64r32, VsrD(0), NMADD_FLGS, 1)
VSX_MADD(XSNMSUBSP, 1, float64r32, VsrD(0), NMSUB_FLGS, 1)

VSX_MADD(xvmadddp, 2, float64, VsrD(i), MADD_FLGS, 0)
VSX_MADD(xvmsubdp, 2, float64, VsrD(i), MSUB_FLGS, 0)
VSX_MADD(xvnmadddp, 2, float64, VsrD(i), NMADD_FLGS, 0)
VSX_MADD(xvnmsubdp, 2, float64, VsrD(i), NMSUB_FLGS, 0)

VSX_MADD(xvmaddsp, 4, float32, VsrW(i), MADD_FLGS, 0)
VSX_MADD(xvmsubsp, 4, float32, VsrW(i), MSUB_FLGS, 0)
VSX_MADD(xvnmaddsp, 4, float32, VsrW(i), NMADD_FLGS, 0)
VSX_MADD(xvnmsubsp, 4, float32, VsrW(i), NMSUB_FLGS, 0)

/*
* VSX_MADDQ - VSX floating point quad-precision muliply/add
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