[gen]: Generate basic SVE loads and stores

SVE pseudo-relaxation are grouped under `Sv` suffix:

 - `SvV` command a SVE gather load and scatter store
 - `Sv{1,2,3,4}` command a SVE interleave loads and stores'

Generated tests set predicates in such way that single access won't
exceed 128 bit (which is minimal allowed vector length) which allow
them tolerate difference in implemented vector length when run on the
target. Also it aligns with herd's implementation choice of 128 bit
vector length.

Please note that predicate register require another allocator which
implemented via newly introduced `special2` allocator

Signed-off-by: Vladimir Murzin <[email protected]>

gen/AArch64Arch_gen.ml

@@ -35,6 +35,7 @@ let do_morello = C.variant Variant_gen.Morello
 let do_fullkvm = C.variant Variant_gen.FullKVM
 let do_kvm = do_fullkvm || C.variant Variant_gen.KVM
 let do_neon = C.variant Variant_gen.Neon
+let do_sve = C.variant Variant_gen.SVE
 let do_mixed = Variant_gen.is_mixed  C.variant
 let do_cu = C.variant Variant_gen.ConstrainedUnpredictable
 
@@ -60,7 +61,7 @@ module Mixed =
 let bellatom = false
 module SIMD = struct
 
-  type atom = NeP|NeAcqPc|NeRel|Ne1|Ne2|Ne3|Ne4|Ne2i|Ne3i|Ne4i|NePa|NePaN
+  type atom = SvV|Sv1|Sv2i|Sv3i|Sv4i|NeP|NeAcqPc|NeRel|Ne1|Ne2|Ne3|Ne4|Ne2i|Ne3i|Ne4i|NePa|NePaN
 
   let fold_neon f r = r |>
     f NeAcqPc |> f NeRel |>
@@ -69,26 +70,35 @@ module SIMD = struct
     f Ne1 |> f Ne2 |> f Ne3 |> f Ne4 |>
     f Ne2i |> f Ne3i |> f Ne4i
 
+  let fold_sve f r = r |>
+    f SvV  |> f Sv1 |>
+    f Sv2i |> f Sv3i |> f Sv4i
+
   let nregs = function
-    | Ne1 -> 1
-    | Ne2 | Ne2i -> 2
-    | Ne3 | Ne3i -> 3
-    | Ne4 | Ne4i -> 4
+    | SvV | Sv1 | Ne1 -> 1
+    | Sv2i | Ne2 | Ne2i -> 2
+    | Sv3i | Ne3 | Ne3i -> 3
+    | Sv4i | Ne4 | Ne4i -> 4
     | _ -> 1
 
   let nelements = function
+    | SvV|Sv1|Sv2i|Sv3i|Sv4i
     | Ne1|Ne2|Ne2i|Ne3|Ne3i|Ne4|Ne4i -> 4
     | NePa|NePaN -> 2
     | NeP | NeAcqPc | NeRel -> 1
 
   let pp_opt = function
+    | Sv2i | Sv3i | Sv4i
     | Ne2i | Ne3i | Ne4i -> "i"
     | _ -> ""
 
   let pp n =
     match n with
     | Ne1 | Ne2 | Ne3 | Ne4 | Ne2i | Ne3i | Ne4i ->
        Printf.sprintf "Ne%i%s" (nregs n) (pp_opt n)
+    | Sv1 | Sv2i | Sv3i | Sv4i ->
+       Printf.sprintf "Sv%i%s" (nregs n) (pp_opt n)
+    | SvV -> "SvV"
     | NePa -> "NePa"
     | NePaN -> "NePaN"
     | NeP -> "NeP"
@@ -107,9 +117,10 @@ module SIMD = struct
     for k = 0 to sz-1 do
       for i=0 to el-1 do
         let j = match n with
-          | Ne2i | Ne3i | Ne4i -> k+i*sz
+          | Sv2i | Sv3i | Sv4i | Ne2i | Ne3i | Ne4i -> k+i*sz
           | NeP | NeAcqPc | NeRel | NePa | NePaN
-          | Ne1 | Ne2 | Ne3 | Ne4 -> i+k*el
+          | Ne1 | Ne2 | Ne3 | Ne4
+          | SvV | Sv1 -> i+k*el
         in
        v.(j) <- start+k
       done
@@ -120,9 +131,10 @@ module SIMD = struct
     let el = nelements n in
     let sz = nregs n in
     let access r k = match n with
-      | Ne2i | Ne3i | Ne4i -> sz*k + r
+      | Sv2i | Sv3i | Sv4i | Ne2i | Ne3i | Ne4i -> sz*k + r
       | NeP | NeAcqPc | NeRel | NePa | NePaN
-      | Ne1 | Ne2 | Ne3 | Ne4 -> el*r + k
+      | Ne1 | Ne2 | Ne3 | Ne4
+      | SvV | Sv1 -> el*r + k
     in
     let rec reg r k =
       if k >= el then []
@@ -335,6 +347,12 @@ let is_ifetch a = match a with
      else
        fun _ r -> r
 
+   let fold_sve =
+     if do_sve then
+       fun f -> SIMD.fold_sve (fun n -> f (Neon n))
+     else
+       fun _ r -> r
+
       let fold_pair f r =
         if do_mixed then r
         else
@@ -357,6 +375,7 @@ let is_ifetch a = match a with
      let r = fold_morello f r in
      let r = fold_tag f r in
      let r = fold_neon f r in
+     let r = fold_sve f r in
      let r = fold_pair f r in
      let r = fold_acc_opt None f r in
      let r =
@@ -456,10 +475,10 @@ let is_ifetch a = match a with
      function
      | NeP | NeAcqPc | NeRel -> 1
      | NePa | NePaN -> 2
-     | Ne1 -> 4
-     | Ne2 | Ne2i -> 8
-     | Ne3 | Ne3i -> 12
-     | Ne4 | Ne4i -> 16
+     | SvV | Sv1  | Ne1 -> 4
+     | Sv2i | Ne2 | Ne2i -> 8
+     | Sv3i | Ne3 | Ne3i -> 12
+     | Sv4i | Ne4 | Ne4i -> 16
 
    let atom_to_bank = function
    | Tag,None -> Code.Tag
@@ -866,6 +885,7 @@ include
 
       type special = reg
       let specials = vregs
+      let specials2 = pregs
     end)
 
 end