Re: [PATCH RFC 3/3] target/arm: Implement SVE2 FCVTXNT

[Richard Henderson]

On 4/28/20 10:43 AM, Stephen Long wrote:
> +void HELPER(sve2_fcvtxnt)(void *vd, void *vn, void *vg,
> +  void *status, uint32_t desc)
> +{
> +set_float_rounding_mode(float_round_to_odd, status);
> +HELPER(sve2_fcvtnt_ds)(vd, vn, vg, status, desc);
> +}

This is incorrect, as it leaves the rounding mode set to odd.

I've adjusted trans_FCVTXNT to the existing do_frint_mode, which handles
switching to and back from a fixed rounding mode.


r~

[PATCH RFC 3/3] target/arm: Implement SVE2 FCVTXNT

[Stephen Long]

Signed-off-by: Stephen Long 
---
 target/arm/helper-sve.h| 2 ++
 target/arm/sve.decode  | 1 +
 target/arm/sve_helper.c| 7 +++
 target/arm/translate-sve.c | 8 
 4 files changed, 18 insertions(+)

diff --git a/target/arm/helper-sve.h b/target/arm/helper-sve.h
index 27a8cc2cbe..c18e4c01b0 100644
--- a/target/arm/helper-sve.h
+++ b/target/arm/helper-sve.h
@@ -2714,6 +2714,8 @@ DEF_HELPER_FLAGS_5(sve2_sqdmlsl_idx_s, TCG_CALL_NO_RWG,
 DEF_HELPER_FLAGS_5(sve2_sqdmlsl_idx_d, TCG_CALL_NO_RWG,
void, ptr, ptr, ptr, ptr, i32)
 
+DEF_HELPER_FLAGS_5(sve2_fcvtxnt, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, ptr, 
i32)
+
 DEF_HELPER_FLAGS_5(sve2_fcvtnt_sh, TCG_CALL_NO_RWG,
void, ptr, ptr, ptr, ptr, i32)
 DEF_HELPER_FLAGS_5(sve2_fcvtnt_ds, TCG_CALL_NO_RWG,
diff --git a/target/arm/sve.decode b/target/arm/sve.decode
index 95fc7ee32c..cb4ed70698 100644
--- a/target/arm/sve.decode
+++ b/target/arm/sve.decode
@@ -1480,6 +1480,7 @@ STNT1_zprz  1110010 .. 10 . 001 ... . . \
 @rprr_scatter_store xs=0 esz=2 scale=0
 
 ### SVE2 floating-point convert precision odd elements
+FCVTXNT 01100100 00 0010 10 101 ... . . @rd_pg_rn_e0
 FCVTNT_sh   01100100 10 0010 00 101 ... . . @rd_pg_rn_e0
 FCVTLT_hs   01100100 10 0010 01 101 ... . . @rd_pg_rn_e0
 FCVTNT_ds   01100100 11 0010 10 101 ... . . @rd_pg_rn_e0
diff --git a/target/arm/sve_helper.c b/target/arm/sve_helper.c
index 8461d84445..56836d91cc 100644
--- a/target/arm/sve_helper.c
+++ b/target/arm/sve_helper.c
@@ -7591,6 +7591,13 @@ void HELPER(NAME)(void *vd, void *vn, void *vg, void 
*status, uint32_t desc)  \
 DO_FCVTNT(sve2_fcvtnt_sh, uint32_t, uint16_t, H1_4, H1_2, sve_f32_to_f16)
 DO_FCVTNT(sve2_fcvtnt_ds, uint64_t, uint32_t, H1_4, H1_2, float64_to_float32)
 
+void HELPER(sve2_fcvtxnt)(void *vd, void *vn, void *vg,
+  void *status, uint32_t desc)
+{
+set_float_rounding_mode(float_round_to_odd, status);
+HELPER(sve2_fcvtnt_ds)(vd, vn, vg, status, desc);
+}
+
 #define DO_FCVTLT(NAME, TYPEW, TYPEN, HW, HN, OP) \
 void HELPER(NAME)(void *vd, void *vn, void *vg, void *status, uint32_t desc)  \
 { \
diff --git a/target/arm/translate-sve.c b/target/arm/translate-sve.c
index 220ff19348..b1cf24f6e7 100644
--- a/target/arm/translate-sve.c
+++ b/target/arm/translate-sve.c
@@ -8106,6 +8106,14 @@ static bool trans_SQRDCMLAH_(DisasContext *s, 
arg_CMLA_ *a)
 return do_sve2__fn(s, a->rd, a->rn, a->rm, a->ra, fns[a->esz], a->rot);
 }
 
+static bool trans_FCVTXNT(DisasContext *s, arg_rpr_esz *a)
+{
+if (!dc_isar_feature(aa64_sve2, s)) {
+return false;
+}
+return do_zpz_ptr(s, a->rd, a->rn, a->pg, false, gen_helper_sve2_fcvtxnt);
+}
+
 static bool trans_FCVTNT_sh(DisasContext *s, arg_rpr_esz *a)
 {
 if (!dc_isar_feature(aa64_sve2, s)) {
-- 
2.17.1