[PULL 15/29] target/arm: Convert Logical (immediate) to decodetree

[Peter Maydell <peter.maydell@linaro.org>]

From: Richard Henderson <richard.henderson@linaro.org>

Convert the ADD, ORR, EOR, ANDS (immediate) instructions.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20230512144106.3608981-10-peter.maydell@linaro.org
[PMM: rebased]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/arm/tcg/a64.decode      | 15 ++++++
 target/arm/tcg/translate-a64.c | 94 +++++++++++-----------------------
 2 files changed, 44 insertions(+), 65 deletions(-)

diff --git a/target/arm/tcg/a64.decode b/target/arm/tcg/a64.decode
index ed03d9e1349..1933afa457b 100644
--- a/target/arm/tcg/a64.decode
+++ b/target/arm/tcg/a64.decode
@@ -56,3 +56,18 @@ SUBS_i          . 11 100010 1 ............ ..... .....  @addsub_imm12
 
 ADDG_i          1 00 100011 0 ...... 00 .... ..... ..... @addsub_imm_tag
 SUBG_i          1 10 100011 0 ...... 00 .... ..... ..... @addsub_imm_tag
+
+# Logical (immediate)
+
+&rri_log        rd rn sf dbm
+@logic_imm_64   1 .. ...... dbm:13 rn:5 rd:5            &rri_log sf=1
+@logic_imm_32   0 .. ...... 0 dbm:12 rn:5 rd:5          &rri_log sf=0
+
+AND_i           . 00 100100 . ...... ...... ..... ..... @logic_imm_64
+AND_i           . 00 100100 . ...... ...... ..... ..... @logic_imm_32
+ORR_i           . 01 100100 . ...... ...... ..... ..... @logic_imm_64
+ORR_i           . 01 100100 . ...... ...... ..... ..... @logic_imm_32
+EOR_i           . 10 100100 . ...... ...... ..... ..... @logic_imm_64
+EOR_i           . 10 100100 . ...... ...... ..... ..... @logic_imm_32
+ANDS_i          . 11 100100 . ...... ...... ..... ..... @logic_imm_64
+ANDS_i          . 11 100100 . ...... ...... ..... ..... @logic_imm_32
diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index c744477d71a..4192f951d48 100644
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -4288,7 +4288,12 @@ static uint64_t bitfield_replicate(uint64_t mask, unsigned int e)
     return mask;
 }
 
-/* Simplified variant of pseudocode DecodeBitMasks() for the case where we
+/*
+ * Logical (immediate)
+ */
+
+/*
+ * Simplified variant of pseudocode DecodeBitMasks() for the case where we
  * only require the wmask. Returns false if the imms/immr/immn are a reserved
  * value (ie should cause a guest UNDEF exception), and true if they are
  * valid, in which case the decoded bit pattern is written to result.
@@ -4354,78 +4359,40 @@ bool logic_imm_decode_wmask(uint64_t *result, unsigned int immn,
     return true;
 }
 
-/* Logical (immediate)
- *   31  30 29 28         23 22  21  16 15  10 9    5 4    0
- * +----+-----+-------------+---+------+------+------+------+
- * | sf | opc | 1 0 0 1 0 0 | N | immr | imms |  Rn  |  Rd  |
- * +----+-----+-------------+---+------+------+------+------+
- */
-static void disas_logic_imm(DisasContext *s, uint32_t insn)
+static bool gen_rri_log(DisasContext *s, arg_rri_log *a, bool set_cc,
+                        void (*fn)(TCGv_i64, TCGv_i64, int64_t))
 {
-    unsigned int sf, opc, is_n, immr, imms, rn, rd;
     TCGv_i64 tcg_rd, tcg_rn;
-    uint64_t wmask;
-    bool is_and = false;
+    uint64_t imm;
 
-    sf = extract32(insn, 31, 1);
-    opc = extract32(insn, 29, 2);
-    is_n = extract32(insn, 22, 1);
-    immr = extract32(insn, 16, 6);
-    imms = extract32(insn, 10, 6);
-    rn = extract32(insn, 5, 5);
-    rd = extract32(insn, 0, 5);
-
-    if (!sf && is_n) {
-        unallocated_encoding(s);
-        return;
+    /* Some immediate field values are reserved. */
+    if (!logic_imm_decode_wmask(&imm, extract32(a->dbm, 12, 1),
+                                extract32(a->dbm, 0, 6),
+                                extract32(a->dbm, 6, 6))) {
+        return false;
+    }
+    if (!a->sf) {
+        imm &= 0xffffffffull;
     }
 
-    if (opc == 0x3) { /* ANDS */
-        tcg_rd = cpu_reg(s, rd);
-    } else {
-        tcg_rd = cpu_reg_sp(s, rd);
-    }
-    tcg_rn = cpu_reg(s, rn);
+    tcg_rd = set_cc ? cpu_reg(s, a->rd) : cpu_reg_sp(s, a->rd);
+    tcg_rn = cpu_reg(s, a->rn);
 
-    if (!logic_imm_decode_wmask(&wmask, is_n, imms, immr)) {
-        /* some immediate field values are reserved */
-        unallocated_encoding(s);
-        return;
+    fn(tcg_rd, tcg_rn, imm);
+    if (set_cc) {
+        gen_logic_CC(a->sf, tcg_rd);
     }
-
-    if (!sf) {
-        wmask &= 0xffffffff;
-    }
-
-    switch (opc) {
-    case 0x3: /* ANDS */
-    case 0x0: /* AND */
-        tcg_gen_andi_i64(tcg_rd, tcg_rn, wmask);
-        is_and = true;
-        break;
-    case 0x1: /* ORR */
-        tcg_gen_ori_i64(tcg_rd, tcg_rn, wmask);
-        break;
-    case 0x2: /* EOR */
-        tcg_gen_xori_i64(tcg_rd, tcg_rn, wmask);
-        break;
-    default:
-        assert(FALSE); /* must handle all above */
-        break;
-    }
-
-    if (!sf && !is_and) {
-        /* zero extend final result; we know we can skip this for AND
-         * since the immediate had the high 32 bits clear.
-         */
+    if (!a->sf) {
         tcg_gen_ext32u_i64(tcg_rd, tcg_rd);
     }
-
-    if (opc == 3) { /* ANDS */
-        gen_logic_CC(sf, tcg_rd);
-    }
+    return true;
 }
 
+TRANS(AND_i, gen_rri_log, a, false, tcg_gen_andi_i64)
+TRANS(ORR_i, gen_rri_log, a, false, tcg_gen_ori_i64)
+TRANS(EOR_i, gen_rri_log, a, false, tcg_gen_xori_i64)
+TRANS(ANDS_i, gen_rri_log, a, true, tcg_gen_andi_i64)
+
 /*
  * Move wide (immediate)
  *
@@ -4618,9 +4585,6 @@ static void disas_extract(DisasContext *s, uint32_t insn)
 static void disas_data_proc_imm(DisasContext *s, uint32_t insn)
 {
     switch (extract32(insn, 23, 6)) {
-    case 0x24: /* Logical (immediate) */
-        disas_logic_imm(s, insn);
-        break;
     case 0x25: /* Move wide (immediate) */
         disas_movw_imm(s, insn);
         break;
-- 
2.34.1