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target/arm: Implement fp16 for Neon VRECPS

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Convert the Neon VRECPS insn to using a gvec helper, and
use this to implement the fp16 case.

The phrasing of the new float32_recps_nf() is slightly different from
the old recps_f32() so that it parallels the f16 version; for f16 we
can't assume that flush-to-zero is always enabled.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200828183354.27913-34-peter.maydell@linaro.org
This commit is contained in:
Peter Maydell 2020-08-28 19:33:42 +01:00
parent 635187aaa9
commit ac8c62c4e5
4 changed files with 35 additions and 34 deletions
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4
target/arm/helper.h
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@ -225,7 +225,6 @@ DEF_HELPER_4(vfp_muladdd, f64, f64, f64, f64, ptr)
DEF_HELPER_4(vfp_muladds, f32, f32, f32, f32, ptr)
DEF_HELPER_4(vfp_muladdh, f16, f16, f16, f16, ptr)
DEF_HELPER_3(recps_f32, f32, env, f32, f32)
DEF_HELPER_3(rsqrts_f32, f32, env, f32, f32)
DEF_HELPER_FLAGS_2(recpe_f16, TCG_CALL_NO_RWG, f16, f16, ptr)
DEF_HELPER_FLAGS_2(recpe_f32, TCG_CALL_NO_RWG, f32, f32, ptr)
@ -674,6 +673,9 @@ DEF_HELPER_FLAGS_5(gvec_fmaxnum_s, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, ptr, i3
DEF_HELPER_FLAGS_5(gvec_fminnum_h, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, ptr, i32)
DEF_HELPER_FLAGS_5(gvec_fminnum_s, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, ptr, i32)
DEF_HELPER_FLAGS_5(gvec_recps_nf_h, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, ptr, i32)
DEF_HELPER_FLAGS_5(gvec_recps_nf_s, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, ptr, i32)
DEF_HELPER_FLAGS_5(gvec_fmla_h, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, ptr, i32)
DEF_HELPER_FLAGS_5(gvec_fmla_s, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, ptr, i32)

21
target/arm/translate-neon.c.inc
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@ -1074,6 +1074,7 @@ DO_3S_FP_GVEC(VMLA, gen_helper_gvec_fmla_s, gen_helper_gvec_fmla_h)
DO_3S_FP_GVEC(VMLS, gen_helper_gvec_fmls_s, gen_helper_gvec_fmls_h)
DO_3S_FP_GVEC(VFMA, gen_helper_gvec_vfma_s, gen_helper_gvec_vfma_h)
DO_3S_FP_GVEC(VFMS, gen_helper_gvec_vfms_s, gen_helper_gvec_vfms_h)
DO_3S_FP_GVEC(VRECPS, gen_helper_gvec_recps_nf_s, gen_helper_gvec_recps_nf_h)
WRAP_FP_GVEC(gen_VMAXNM_fp32_3s, FPST_STD, gen_helper_gvec_fmaxnum_s)
WRAP_FP_GVEC(gen_VMAXNM_fp16_3s, FPST_STD_F16, gen_helper_gvec_fmaxnum_h)
@ -1110,26 +1111,6 @@ static bool trans_VMINNM_fp_3s(DisasContext *s, arg_3same *a)
return do_3same(s, a, gen_VMINNM_fp32_3s);
}
WRAP_ENV_FN(gen_VRECPS_tramp, gen_helper_recps_f32)
static void gen_VRECPS_fp_3s(unsigned vece, uint32_t rd_ofs,
uint32_t rn_ofs, uint32_t rm_ofs,
uint32_t oprsz, uint32_t maxsz)
{
static const GVecGen3 ops = { .fni4 = gen_VRECPS_tramp };
tcg_gen_gvec_3(rd_ofs, rn_ofs, rm_ofs, oprsz, maxsz, &ops);
}
static bool trans_VRECPS_fp_3s(DisasContext *s, arg_3same *a)
{
if (a->size != 0) {
/* TODO fp16 support */
return false;
}
return do_3same(s, a, gen_VRECPS_fp_3s);
}
WRAP_ENV_FN(gen_VRSQRTS_tramp, gen_helper_rsqrts_f32)
static void gen_VRSQRTS_fp_3s(unsigned vece, uint32_t rd_ofs,

31
target/arm/vec_helper.c
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@ -797,6 +797,34 @@ static float32 float32_abd(float32 op1, float32 op2, float_status *stat)
return float32_abs(float32_sub(op1, op2, stat));
}
/*
* Reciprocal step. These are the AArch32 version which uses a
* non-fused multiply-and-subtract.
*/
static float16 float16_recps_nf(float16 op1, float16 op2, float_status *stat)
{
op1 = float16_squash_input_denormal(op1, stat);
op2 = float16_squash_input_denormal(op2, stat);
if ((float16_is_infinity(op1) && float16_is_zero(op2)) ||
(float16_is_infinity(op2) && float16_is_zero(op1))) {
return float16_two;
}
return float16_sub(float16_two, float16_mul(op1, op2, stat), stat);
}
static float32 float32_recps_nf(float32 op1, float32 op2, float_status *stat)
{
op1 = float32_squash_input_denormal(op1, stat);
op2 = float32_squash_input_denormal(op2, stat);
if ((float32_is_infinity(op1) && float32_is_zero(op2)) ||
(float32_is_infinity(op2) && float32_is_zero(op1))) {
return float32_two;
}
return float32_sub(float32_two, float32_mul(op1, op2, stat), stat);
}
#define DO_3OP(NAME, FUNC, TYPE) \
void HELPER(NAME)(void *vd, void *vn, void *vm, void *stat, uint32_t desc) \
{ \
@ -854,6 +882,9 @@ DO_3OP(gvec_fmaxnum_s, float32_maxnum, float32)
DO_3OP(gvec_fminnum_h, float16_minnum, float16)
DO_3OP(gvec_fminnum_s, float32_minnum, float32)
DO_3OP(gvec_recps_nf_h, float16_recps_nf, float16)
DO_3OP(gvec_recps_nf_s, float32_recps_nf, float32)
#ifdef TARGET_AARCH64
DO_3OP(gvec_recps_h, helper_recpsf_f16, float16)

13
target/arm/vfp_helper.c
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@ -529,19 +529,6 @@ uint32_t HELPER(vfp_fcvt_f64_to_f16)(float64 a, void *fpstp, uint32_t ahp_mode)
return r;
}
float32 HELPER(recps_f32)(CPUARMState *env, float32 a, float32 b)
{
float_status *s = &env->vfp.standard_fp_status;
if ((float32_is_infinity(a) && float32_is_zero_or_denormal(b)) ||
(float32_is_infinity(b) && float32_is_zero_or_denormal(a))) {
if (!(float32_is_zero(a) || float32_is_zero(b))) {
float_raise(float_flag_input_denormal, s);
}
return float32_two;
}
return float32_sub(float32_two, float32_mul(a, b, s), s);
}
float32 HELPER(rsqrts_f32)(CPUARMState *env, float32 a, float32 b)
{
float_status *s = &env->vfp.standard_fp_status;