target/arm: Split trans_WHILE to lt and gt

Use TRANS_FEAT to select the correct predicate.
Pass the helper and a boolean to do_WHILE.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20250704142112.1018902-77-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

target/arm/tcg/sve.decode

@@ -789,7 +789,9 @@ SINCDECP_z      00100101 .. 1010 d:1 u:1 10000 00 .... .....    @incdec2_pred
 CTERM           00100101 1 sf:1 1 rm:5 001000 rn:5 ne:1 0000
 
 # SVE integer compare scalar count and limit
-WHILE           00100101 esz:2 1 rm:5 000 sf:1 u:1 lt:1 rn:5 eq:1 rd:4
+&while          esz rd rn rm sf u eq
+WHILE_lt        00100101 esz:2 1 rm:5 000 sf:1 u:1 1 rn:5 eq:1 rd:4  &while
+WHILE_gt        00100101 esz:2 1 rm:5 000 sf:1 u:1 0 rn:5 eq:1 rd:4  &while
 
 # SVE2 pointer conflict compare
 WHILE_ptr       00100101 esz:2 1 rm:5 001 100 rn:5 rw:1 rd:4

target/arm/tcg/translate-sve.c

@@ -3108,7 +3108,8 @@ static bool trans_CTERM(DisasContext *s, arg_CTERM *a)
     return true;
 }
 
-static bool trans_WHILE(DisasContext *s, arg_WHILE *a)
+typedef void gen_while_fn(TCGv_i32, TCGv_ptr, TCGv_i32, TCGv_i32);
+static bool do_WHILE(DisasContext *s, arg_while *a, bool lt, gen_while_fn *fn)
 {
     TCGv_i64 op0, op1, t0, t1, tmax;
     TCGv_i32 t2;
@@ -3118,14 +3119,8 @@ static bool trans_WHILE(DisasContext *s, arg_WHILE *a)
     TCGCond cond;
     uint64_t maxval;
     /* Note that GE/HS has a->eq == 0 and GT/HI has a->eq == 1. */
-    bool eq = a->eq == a->lt;
+    bool eq = a->eq == lt;
 
-    /* The greater-than conditions are all SVE2. */
-    if (a->lt
-        ? !dc_isar_feature(aa64_sve, s)
-        : !dc_isar_feature(aa64_sve2, s)) {
-        return false;
-    }
     if (!sve_access_check(s)) {
         return true;
     }
@@ -3149,7 +3144,7 @@ static bool trans_WHILE(DisasContext *s, arg_WHILE *a)
     t0 = tcg_temp_new_i64();
     t1 = tcg_temp_new_i64();
 
-    if (a->lt) {
+    if (lt) {
         tcg_gen_sub_i64(t0, op1, op0);
         if (a->u) {
             maxval = a->sf ? UINT64_MAX : UINT32_MAX;
@@ -3204,15 +3199,15 @@ static bool trans_WHILE(DisasContext *s, arg_WHILE *a)
     ptr = tcg_temp_new_ptr();
     tcg_gen_addi_ptr(ptr, tcg_env, pred_full_reg_offset(s, a->rd));
 
-    if (a->lt) {
-        gen_helper_sve_whilel(t2, ptr, t2, tcg_constant_i32(desc));
-    } else {
-        gen_helper_sve_whileg(t2, ptr, t2, tcg_constant_i32(desc));
-    }
+    fn(t2, ptr, t2, tcg_constant_i32(desc));
+
     do_pred_flags(t2);
     return true;
 }
 
+TRANS_FEAT(WHILE_lt, aa64_sve, do_WHILE, a, true, gen_helper_sve_whilel)
+TRANS_FEAT(WHILE_gt, aa64_sve2, do_WHILE, a, false, gen_helper_sve_whileg)
+
 static bool trans_WHILE_ptr(DisasContext *s, arg_WHILE_ptr *a)
 {
     TCGv_i64 op0, op1, diff, t1, tmax;