From 7c51048fa918f64806adf0f76166e9940d772eb1 Mon Sep 17 00:00:00 2001 From: Michael Matz Date: Fri, 31 Jan 2014 14:47:31 +0000 Subject: [PATCH] target-arm: A64: Add SIMD TBL/TBLX Add support for the SIMD TBL/TBLX instructions (group C3.6.2). Signed-off-by: Michael Matz [PMM: rewritten to do more of the decode in translate-a64.c, and to do only one 64 bit pass at a time in the helper] Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson --- target-arm/helper-a64.c | 31 +++++++++++++++++++++ target-arm/helper-a64.h | 1 + target-arm/translate-a64.c | 55 +++++++++++++++++++++++++++++++++++++- 3 files changed, 86 insertions(+), 1 deletion(-) diff --git a/target-arm/helper-a64.c b/target-arm/helper-a64.c index 4ce0d01a85..6ca958afb1 100644 --- a/target-arm/helper-a64.c +++ b/target-arm/helper-a64.c @@ -122,3 +122,34 @@ uint64_t HELPER(vfp_cmped_a64)(float64 x, float64 y, void *fp_status) { return float_rel_to_flags(float64_compare(x, y, fp_status)); } + +uint64_t HELPER(simd_tbl)(CPUARMState *env, uint64_t result, uint64_t indices, + uint32_t rn, uint32_t numregs) +{ + /* Helper function for SIMD TBL and TBX. We have to do the table + * lookup part for the 64 bits worth of indices we're passed in. + * result is the initial results vector (either zeroes for TBL + * or some guest values for TBX), rn the register number where + * the table starts, and numregs the number of registers in the table. + * We return the results of the lookups. + */ + int shift; + + for (shift = 0; shift < 64; shift += 8) { + int index = extract64(indices, shift, 8); + if (index < 16 * numregs) { + /* Convert index (a byte offset into the virtual table + * which is a series of 128-bit vectors concatenated) + * into the correct vfp.regs[] element plus a bit offset + * into that element, bearing in mind that the table + * can wrap around from V31 to V0. + */ + int elt = (rn * 2 + (index >> 3)) % 64; + int bitidx = (index & 7) * 8; + uint64_t val = extract64(env->vfp.regs[elt], bitidx, 8); + + result = deposit64(result, shift, 8, val); + } + } + return result; +} diff --git a/target-arm/helper-a64.h b/target-arm/helper-a64.h index bca19f3dea..99832ee55e 100644 --- a/target-arm/helper-a64.h +++ b/target-arm/helper-a64.h @@ -26,3 +26,4 @@ DEF_HELPER_3(vfp_cmps_a64, i64, f32, f32, ptr) DEF_HELPER_3(vfp_cmpes_a64, i64, f32, f32, ptr) DEF_HELPER_3(vfp_cmpd_a64, i64, f64, f64, ptr) DEF_HELPER_3(vfp_cmped_a64, i64, f64, f64, ptr) +DEF_HELPER_FLAGS_5(simd_tbl, TCG_CALL_NO_RWG_SE, i64, env, i64, i64, i32, i32) diff --git a/target-arm/translate-a64.c b/target-arm/translate-a64.c index 75b00392bc..7a6b00a938 100644 --- a/target-arm/translate-a64.c +++ b/target-arm/translate-a64.c @@ -4742,7 +4742,60 @@ static void disas_simd_ext(DisasContext *s, uint32_t insn) */ static void disas_simd_tb(DisasContext *s, uint32_t insn) { - unsupported_encoding(s, insn); + int op2 = extract32(insn, 22, 2); + int is_q = extract32(insn, 30, 1); + int rm = extract32(insn, 16, 5); + int rn = extract32(insn, 5, 5); + int rd = extract32(insn, 0, 5); + int is_tblx = extract32(insn, 12, 1); + int len = extract32(insn, 13, 2); + TCGv_i64 tcg_resl, tcg_resh, tcg_idx; + TCGv_i32 tcg_regno, tcg_numregs; + + if (op2 != 0) { + unallocated_encoding(s); + return; + } + + /* This does a table lookup: for every byte element in the input + * we index into a table formed from up to four vector registers, + * and then the output is the result of the lookups. Our helper + * function does the lookup operation for a single 64 bit part of + * the input. + */ + tcg_resl = tcg_temp_new_i64(); + tcg_resh = tcg_temp_new_i64(); + + if (is_tblx) { + read_vec_element(s, tcg_resl, rd, 0, MO_64); + } else { + tcg_gen_movi_i64(tcg_resl, 0); + } + if (is_tblx && is_q) { + read_vec_element(s, tcg_resh, rd, 1, MO_64); + } else { + tcg_gen_movi_i64(tcg_resh, 0); + } + + tcg_idx = tcg_temp_new_i64(); + tcg_regno = tcg_const_i32(rn); + tcg_numregs = tcg_const_i32(len + 1); + read_vec_element(s, tcg_idx, rm, 0, MO_64); + gen_helper_simd_tbl(tcg_resl, cpu_env, tcg_resl, tcg_idx, + tcg_regno, tcg_numregs); + if (is_q) { + read_vec_element(s, tcg_idx, rm, 1, MO_64); + gen_helper_simd_tbl(tcg_resh, cpu_env, tcg_resh, tcg_idx, + tcg_regno, tcg_numregs); + } + tcg_temp_free_i64(tcg_idx); + tcg_temp_free_i32(tcg_regno); + tcg_temp_free_i32(tcg_numregs); + + write_vec_element(s, tcg_resl, rd, 0, MO_64); + tcg_temp_free_i64(tcg_resl); + write_vec_element(s, tcg_resh, rd, 1, MO_64); + tcg_temp_free_i64(tcg_resh); } /* C3.6.3 ZIP/UZP/TRN