From 47810f99e846501c817fb77ebd03b6914342f7e5 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Fri, 4 Jul 2025 08:20:50 -0600 Subject: [PATCH] target/arm: Implement CNTP (predicate as counter) for SME2/SVE2p1 Reviewed-by: Peter Maydell Signed-off-by: Richard Henderson Message-id: 20250704142112.1018902-88-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- target/arm/tcg/helper-sve.h | 1 + target/arm/tcg/sve.decode | 3 ++- target/arm/tcg/sve_helper.c | 21 +++++++++++++++++++++ target/arm/tcg/translate-sve.c | 30 ++++++++++++++++++++++++++++++ 4 files changed, 54 insertions(+), 1 deletion(-) diff --git a/target/arm/tcg/helper-sve.h b/target/arm/tcg/helper-sve.h index 906da384dc4..733828a8806 100644 --- a/target/arm/tcg/helper-sve.h +++ b/target/arm/tcg/helper-sve.h @@ -937,6 +937,7 @@ DEF_HELPER_FLAGS_4(sve_brkn, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, i32) DEF_HELPER_FLAGS_4(sve_brkns, TCG_CALL_NO_RWG, i32, ptr, ptr, ptr, i32) DEF_HELPER_FLAGS_3(sve_cntp, TCG_CALL_NO_RWG, i64, ptr, ptr, i32) +DEF_HELPER_FLAGS_2(sve2p1_cntp_c, TCG_CALL_NO_RWG_SE, i64, i32, i32) DEF_HELPER_FLAGS_3(sve_whilel, TCG_CALL_NO_RWG, i32, ptr, i32, i32) DEF_HELPER_FLAGS_3(sve_whileg, TCG_CALL_NO_RWG, i32, ptr, i32, i32) diff --git a/target/arm/tcg/sve.decode b/target/arm/tcg/sve.decode index 0df33127395..db16849731d 100644 --- a/target/arm/tcg/sve.decode +++ b/target/arm/tcg/sve.decode @@ -784,7 +784,8 @@ BRKN 00100101 0. 01100001 .... 0 .... 0 .... @pd_pg_pn_s ### SVE Predicate Count Group # SVE predicate count -CNTP 00100101 .. 100 000 10 .... 0 .... ..... @rd_pg4_pn +CNTP 00100101 .. 100 000 10 .... 0 .... ..... @rd_pg4_pn +CNTP_c 00100101 esz:2 100 000 10 000 vl:1 1 rn:4 rd:5 # SVE inc/dec register by predicate count INCDECP_r 00100101 .. 10110 d:1 10001 00 .... ..... @incdec_pred u=1 diff --git a/target/arm/tcg/sve_helper.c b/target/arm/tcg/sve_helper.c index 6512df54e60..def841fd52f 100644 --- a/target/arm/tcg/sve_helper.c +++ b/target/arm/tcg/sve_helper.c @@ -4178,6 +4178,27 @@ uint64_t HELPER(sve_cntp)(void *vn, void *vg, uint32_t pred_desc) return sum; } +uint64_t HELPER(sve2p1_cntp_c)(uint32_t png, uint32_t desc) +{ + int pl = FIELD_EX32(desc, PREDDESC, OPRSZ); + int vl = pl * 8; + unsigned v_esz = FIELD_EX32(desc, PREDDESC, ESZ); + int lg2_width = FIELD_EX32(desc, PREDDESC, DATA) + 1; + DecodeCounter p = decode_counter(png, vl, v_esz); + unsigned maxelem = (vl << lg2_width) >> v_esz; + unsigned count = p.count; + + if (p.invert) { + if (count >= maxelem) { + return 0; + } + count = maxelem - count; + } else { + count = MIN(count, maxelem); + } + return count >> p.lg2_stride; +} + /* C.f. Arm pseudocode EncodePredCount */ static uint64_t encode_pred_count(uint32_t elements, uint32_t count, uint32_t esz, bool invert) diff --git a/target/arm/tcg/translate-sve.c b/target/arm/tcg/translate-sve.c index 079d3109607..53db8851bf4 100644 --- a/target/arm/tcg/translate-sve.c +++ b/target/arm/tcg/translate-sve.c @@ -3052,6 +3052,36 @@ static bool trans_CNTP(DisasContext *s, arg_CNTP *a) return true; } +static bool trans_CNTP_c(DisasContext *s, arg_CNTP_c *a) +{ + TCGv_i32 t_png; + uint32_t desc = 0; + + if (dc_isar_feature(aa64_sve2p1, s)) { + if (!sve_access_check(s)) { + return true; + } + } else if (dc_isar_feature(aa64_sme2, s)) { + if (!sme_sm_enabled_check(s)) { + return true; + } + } else { + return false; + } + + t_png = tcg_temp_new_i32(); + tcg_gen_ld16u_i32(t_png, tcg_env, + pred_full_reg_offset(s, a->rn) ^ + (HOST_BIG_ENDIAN ? 6 : 0)); + + desc = FIELD_DP32(desc, PREDDESC, OPRSZ, pred_full_reg_size(s)); + desc = FIELD_DP32(desc, PREDDESC, ESZ, a->esz); + desc = FIELD_DP32(desc, PREDDESC, DATA, a->vl); + + gen_helper_sve2p1_cntp_c(cpu_reg(s, a->rd), t_png, tcg_constant_i32(desc)); + return true; +} + static bool trans_INCDECP_r(DisasContext *s, arg_incdec_pred *a) { if (!dc_isar_feature(aa64_sve, s)) { -- 2.47.2