[v3,13/69] target/arm: Convert disas_add_sub_reg to decodetree

Commit Message

Richard Henderson Dec. 11, 2024, 4:29 p.m. UTC

This includes ADD, SUB, ADDS, SUBS (shifted register).

Reviewed-by: Peter Maydell <[e-mail]>
Signed-off-by: Richard Henderson <[e-mail]>
---
 target/arm/tcg/translate-a64.c | 64 ++++++++++------------------------
 target/arm/tcg/a64.decode      |  9 +++++
 2 files changed, 27 insertions(+), 46 deletions(-)

Patch

diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index 8f777875fe..d570bbb696 100644
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -7912,47 +7912,22 @@  TRANS(SUB_ext, do_addsub_ext, a, true, false)
 TRANS(ADDS_ext, do_addsub_ext, a, false, true)
 TRANS(SUBS_ext, do_addsub_ext, a, true, true)
 
-/*
- * Add/subtract (shifted register)
- *
- *  31 30 29 28       24 23 22 21 20   16 15     10 9    5 4    0
- * +--+--+--+-----------+-----+--+-------+---------+------+------+
- * |sf|op| S| 0 1 0 1 1 |shift| 0|  Rm   |  imm6   |  Rn  |  Rd  |
- * +--+--+--+-----------+-----+--+-------+---------+------+------+
- *
- *    sf: 0 -> 32bit, 1 -> 64bit
- *    op: 0 -> add  , 1 -> sub
- *     S: 1 -> set flags
- * shift: 00 -> LSL, 01 -> LSR, 10 -> ASR, 11 -> RESERVED
- *  imm6: Shift amount to apply to Rm before the add/sub
- */
-static void disas_add_sub_reg(DisasContext *s, uint32_t insn)
+static bool do_addsub_reg(DisasContext *s, arg_addsub_shift *a,
+                          bool sub_op, bool setflags)
 {
-    int rd = extract32(insn, 0, 5);
-    int rn = extract32(insn, 5, 5);
-    int imm6 = extract32(insn, 10, 6);
-    int rm = extract32(insn, 16, 5);
-    int shift_type = extract32(insn, 22, 2);
-    bool setflags = extract32(insn, 29, 1);
-    bool sub_op = extract32(insn, 30, 1);
-    bool sf = extract32(insn, 31, 1);
+    TCGv_i64 tcg_rd, tcg_rn, tcg_rm, tcg_result;
 
-    TCGv_i64 tcg_rd = cpu_reg(s, rd);
-    TCGv_i64 tcg_rn, tcg_rm;
-    TCGv_i64 tcg_result;
-
-    if ((shift_type == 3) || (!sf && (imm6 > 31))) {
-        unallocated_encoding(s);
-        return;
+    if (a->st == 3 || (!a->sf && (a->sa & 32))) {
+        return false;
     }
 
-    tcg_rn = read_cpu_reg(s, rn, sf);
-    tcg_rm = read_cpu_reg(s, rm, sf);
+    tcg_rd = cpu_reg(s, a->rd);
+    tcg_rn = read_cpu_reg(s, a->rn, a->sf);
+    tcg_rm = read_cpu_reg(s, a->rm, a->sf);
 
-    shift_reg_imm(tcg_rm, tcg_rm, sf, shift_type, imm6);
+    shift_reg_imm(tcg_rm, tcg_rm, a->sf, a->st, a->sa);
 
     tcg_result = tcg_temp_new_i64();
-
     if (!setflags) {
         if (sub_op) {
             tcg_gen_sub_i64(tcg_result, tcg_rn, tcg_rm);
@@ -7961,19 +7936,25 @@  static void disas_add_sub_reg(DisasContext *s, uint32_t insn)
         }
     } else {
         if (sub_op) {
-            gen_sub_CC(sf, tcg_result, tcg_rn, tcg_rm);
+            gen_sub_CC(a->sf, tcg_result, tcg_rn, tcg_rm);
         } else {
-            gen_add_CC(sf, tcg_result, tcg_rn, tcg_rm);
+            gen_add_CC(a->sf, tcg_result, tcg_rn, tcg_rm);
         }
     }
 
-    if (sf) {
+    if (a->sf) {
         tcg_gen_mov_i64(tcg_rd, tcg_result);
     } else {
         tcg_gen_ext32u_i64(tcg_rd, tcg_result);
     }
+    return true;
 }
 
+TRANS(ADD_r, do_addsub_reg, a, false, false)
+TRANS(SUB_r, do_addsub_reg, a, true, false)
+TRANS(ADDS_r, do_addsub_reg, a, false, true)
+TRANS(SUBS_r, do_addsub_reg, a, true, true)
+
 /* Data-processing (3 source)
  *
  *    31 30  29 28       24 23 21  20  16  15  14  10 9    5 4    0
@@ -8348,15 +8329,6 @@  static void disas_data_proc_reg(DisasContext *s, uint32_t insn)
     int op3 = extract32(insn, 10, 6);
 
     if (!op1) {
-        if (op2 & 8) {
-            if (op2 & 1) {
-                goto do_unallocated;
-            } else {
-                /* Add/sub (shifted register) */
-                disas_add_sub_reg(s, insn);
-            }
-            return;
-        }
         goto do_unallocated;
     }
 
diff --git a/target/arm/tcg/a64.decode b/target/arm/tcg/a64.decode
index 0539694506..27a3101bc6 100644
--- a/target/arm/tcg/a64.decode
+++ b/target/arm/tcg/a64.decode
@@ -726,6 +726,15 @@  EOR_r           . 10 01010 .. . ..... ...... ..... .....    @logic_shift
 ANDS_r          . 11 01010 .. . ..... ...... ..... .....    @logic_shift
 
 # Add/subtract (shifted reg)
+
+&addsub_shift    rd rn rm sf sa st
+@addsub_shift    sf:1 .. ..... st:2 . rm:5 sa:6 rn:5 rd:5   &addsub_shift
+
+ADD_r           . 00 01011 .. 0 ..... ...... ..... .....    @addsub_shift
+SUB_r           . 10 01011 .. 0 ..... ...... ..... .....    @addsub_shift
+ADDS_r          . 01 01011 .. 0 ..... ...... ..... .....    @addsub_shift
+SUBS_r          . 11 01011 .. 0 ..... ...... ..... .....    @addsub_shift
+
 # Add/subtract (extended reg)
 
 &addsub_ext     rd rn rm sf sa st