target/arm: Decode aa32 armv8.3 2-reg-index

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180228193125.20577-15-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 61 insertions, 0 deletions

diff --git a/target/arm/translate.c b/target/arm/translate.c
index 45513c9d86..3ad8b4031c 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -7742,6 +7742,61 @@ static int disas_neon_insn_3same_ext(DisasContext *s, uint32_t insn)
     return 0;
 }
 
+/* Advanced SIMD two registers and a scalar extension.
+ *  31             24   23  22   20   16   12  11   10   9    8        3     0
+ * +-----------------+----+---+----+----+----+---+----+---+----+---------+----+
+ * | 1 1 1 1 1 1 1 0 | o1 | D | o2 | Vn | Vd | 1 | o3 | 0 | o4 | N Q M U | Vm |
+ * +-----------------+----+---+----+----+----+---+----+---+----+---------+----+
+ *
+ */
+
+static int disas_neon_insn_2reg_scalar_ext(DisasContext *s, uint32_t insn)
+{
+    int rd, rn, rm, rot, size, opr_sz;
+    TCGv_ptr fpst;
+    bool q;
+
+    q = extract32(insn, 6, 1);
+    VFP_DREG_D(rd, insn);
+    VFP_DREG_N(rn, insn);
+    VFP_DREG_M(rm, insn);
+    if ((rd | rn) & q) {
+        return 1;
+    }
+
+    if ((insn & 0xff000f10) == 0xfe000800) {
+        /* VCMLA (indexed) -- 1111 1110 S.RR .... .... 1000 ...0 .... */
+        rot = extract32(insn, 20, 2);
+        size = extract32(insn, 23, 1);
+        if (!arm_dc_feature(s, ARM_FEATURE_V8_FCMA)
+            || (!size && !arm_dc_feature(s, ARM_FEATURE_V8_FP16))) {
+            return 1;
+        }
+    } else {
+        return 1;
+    }
+
+    if (s->fp_excp_el) {
+        gen_exception_insn(s, 4, EXCP_UDEF,
+                           syn_fp_access_trap(1, 0xe, false), s->fp_excp_el);
+        return 0;
+    }
+    if (!s->vfp_enabled) {
+        return 1;
+    }
+
+    opr_sz = (1 + q) * 8;
+    fpst = get_fpstatus_ptr(1);
+    tcg_gen_gvec_3_ptr(vfp_reg_offset(1, rd),
+                       vfp_reg_offset(1, rn),
+                       vfp_reg_offset(1, rm), fpst,
+                       opr_sz, opr_sz, rot,
+                       size ? gen_helper_gvec_fcmlas_idx
+                       : gen_helper_gvec_fcmlah_idx);
+    tcg_temp_free_ptr(fpst);
+    return 0;
+}
+
 static int disas_coproc_insn(DisasContext *s, uint32_t insn)
 {
     int cpnum, is64, crn, crm, opc1, opc2, isread, rt, rt2;
@@ -8492,6 +8547,12 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn)
                 goto illegal_op;
             }
             return;
+        } else if ((insn & 0x0f000a00) == 0x0e000800
+                   && arm_dc_feature(s, ARM_FEATURE_V8)) {
+            if (disas_neon_insn_2reg_scalar_ext(s, insn)) {
+                goto illegal_op;
+            }
+            return;
         } else if ((insn & 0x0fe00000) == 0x0c400000) {
             /* Coprocessor double register transfer.  */
             ARCH(5TE);