target/arm: Introduce fp_access_check_vector_hsd

Provide a simple way to check for float64, float32, and float16
support vs vector width, as well as the fpu enabled.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241211163036.2297116-22-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

target/arm/tcg/translate-a64.c

@@ -1260,6 +1260,28 @@ static int fp_access_check_scalar_hsd(DisasContext *s, MemOp esz)
     return fp_access_check(s);
 }
 
+/* Likewise, but vector MO_64 must have two elements. */
+static int fp_access_check_vector_hsd(DisasContext *s, bool is_q, MemOp esz)
+{
+    switch (esz) {
+    case MO_64:
+        if (!is_q) {
+            return -1;
+        }
+        break;
+    case MO_32:
+        break;
+    case MO_16:
+        if (!dc_isar_feature(aa64_fp16, s)) {
+            return -1;
+        }
+        break;
+    default:
+        return -1;
+    }
+    return fp_access_check(s);
+}
+
 /*
  * Check that SVE access is enabled.  If it is, return true.
  * If not, emit code to generate an appropriate exception and return false.
@@ -5420,27 +5442,14 @@ static bool do_fp3_vector(DisasContext *s, arg_qrrr_e *a, int data,
                           gen_helper_gvec_3_ptr * const fns[3])
 {
     MemOp esz = a->esz;
+    int check = fp_access_check_vector_hsd(s, a->q, esz);
 
-    switch (esz) {
+    if (check <= 0) {
-    case MO_64:
+        return check == 0;
-        if (!a->q) {
-            return false;
-        }
-        break;
-    case MO_32:
-        break;
-    case MO_16:
-        if (!dc_isar_feature(aa64_fp16, s)) {
-            return false;
-        }
-        break;
-    default:
-        return false;
-    }
-    if (fp_access_check(s)) {
-        gen_gvec_op3_fpst(s, a->q, a->rd, a->rn, a->rm,
-                          esz == MO_16, data, fns[esz - 1]);
     }
+
+    gen_gvec_op3_fpst(s, a->q, a->rd, a->rn, a->rm,
+                      esz == MO_16, data, fns[esz - 1]);
     return true;
 }
 
@@ -5768,34 +5777,24 @@ TRANS_FEAT(FCADD_270, aa64_fcma, do_fp3_vector, a, 1, f_vector_fcadd)
 
 static bool trans_FCMLA_v(DisasContext *s, arg_FCMLA_v *a)
 {
-    gen_helper_gvec_4_ptr *fn;
+    static gen_helper_gvec_4_ptr * const fn[] = {
+        [MO_16] = gen_helper_gvec_fcmlah,
+        [MO_32] = gen_helper_gvec_fcmlas,
+        [MO_64] = gen_helper_gvec_fcmlad,
+    };
+    int check;
 
     if (!dc_isar_feature(aa64_fcma, s)) {
         return false;
     }
-    switch (a->esz) {
+
-    case MO_64:
+    check = fp_access_check_vector_hsd(s, a->q, a->esz);
-        if (!a->q) {
+    if (check <= 0) {
-            return false;
+        return check == 0;
-        }
-        fn = gen_helper_gvec_fcmlad;
-        break;
-    case MO_32:
-        fn = gen_helper_gvec_fcmlas;
-        break;
-    case MO_16:
-        if (!dc_isar_feature(aa64_fp16, s)) {
-            return false;
-        }
-        fn = gen_helper_gvec_fcmlah;
-        break;
-    default:
-        return false;
-    }
-    if (fp_access_check(s)) {
-        gen_gvec_op4_fpst(s, a->q, a->rd, a->rn, a->rm, a->rd,
-                          a->esz == MO_16, a->rot, fn);
     }
+
+    gen_gvec_op4_fpst(s, a->q, a->rd, a->rn, a->rm, a->rd,
+                      a->esz == MO_16, a->rot, fn[a->esz]);
     return true;
 }
 
@@ -6337,27 +6336,14 @@ static bool do_fp3_vector_idx(DisasContext *s, arg_qrrx_e *a,
                               gen_helper_gvec_3_ptr * const fns[3])
 {
     MemOp esz = a->esz;
+    int check = fp_access_check_vector_hsd(s, a->q, esz);
 
-    switch (esz) {
+    if (check <= 0) {
-    case MO_64:
+        return check == 0;
-        if (!a->q) {
-            return false;
-        }
-        break;
-    case MO_32:
-        break;
-    case MO_16:
-        if (!dc_isar_feature(aa64_fp16, s)) {
-            return false;
-        }
-        break;
-    default:
-        g_assert_not_reached();
-    }
-    if (fp_access_check(s)) {
-        gen_gvec_op3_fpst(s, a->q, a->rd, a->rn, a->rm,
-                          esz == MO_16, a->idx, fns[esz - 1]);
     }
+
+    gen_gvec_op3_fpst(s, a->q, a->rd, a->rn, a->rm,
+                      esz == MO_16, a->idx, fns[esz - 1]);
     return true;
 }
 
@@ -6383,28 +6369,15 @@ static bool do_fmla_vector_idx(DisasContext *s, arg_qrrx_e *a, bool neg)
         gen_helper_gvec_fmla_idx_d,
     };
     MemOp esz = a->esz;
+    int check = fp_access_check_vector_hsd(s, a->q, esz);
 
-    switch (esz) {
+    if (check <= 0) {
-    case MO_64:
+        return check == 0;
-        if (!a->q) {
-            return false;
-        }
-        break;
-    case MO_32:
-        break;
-    case MO_16:
-        if (!dc_isar_feature(aa64_fp16, s)) {
-            return false;
-        }
-        break;
-    default:
-        g_assert_not_reached();
-    }
-    if (fp_access_check(s)) {
-        gen_gvec_op4_fpst(s, a->q, a->rd, a->rn, a->rm, a->rd,
-                          esz == MO_16, (a->idx << 1) | neg,
-                          fns[esz - 1]);
     }
+
+    gen_gvec_op4_fpst(s, a->q, a->rd, a->rn, a->rm, a->rd,
+                      esz == MO_16, (a->idx << 1) | neg,
+                      fns[esz - 1]);
     return true;
 }