[PULL 10/29] target/arm: Convert PC-rel addressing to decodetree

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

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

Convert the ADR and ADRP instructions.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20230512144106.3608981-5-peter.maydell@linaro.org
[PMM: Rebased]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/arm/tcg/a64.decode      | 13 ++++++++++++
 target/arm/tcg/translate-a64.c | 38 +++++++++++++---------------------
 2 files changed, 27 insertions(+), 24 deletions(-)

diff --git a/target/arm/tcg/a64.decode b/target/arm/tcg/a64.decode
index 43321bbbb05..bcf46fc37d7 100644
--- a/target/arm/tcg/a64.decode
+++ b/target/arm/tcg/a64.decode
@@ -18,3 +18,16 @@
 #
 # This file is processed by scripts/decodetree.py
 #
+
+&ri              rd imm
+
+
+### Data Processing - Immediate
+
+# PC-rel addressing
+
+%imm_pcrel      5:s19 29:2
+@pcrel          . .. ..... ................... rd:5     &ri imm=%imm_pcrel
+
+ADR             0 .. 10000 ................... .....    @pcrel
+ADRP            1 .. 10000 ................... .....    @pcrel
diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index 1fd6f97b641..ffcd05eb38a 100644
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -4179,31 +4179,24 @@ static void disas_ldst(DisasContext *s, uint32_t insn)
     }
 }
 
-/* PC-rel. addressing
- *   31  30   29 28       24 23                5 4    0
- * +----+-------+-----------+-------------------+------+
- * | op | immlo | 1 0 0 0 0 |       immhi       |  Rd  |
- * +----+-------+-----------+-------------------+------+
+/*
+ * PC-rel. addressing
  */
-static void disas_pc_rel_adr(DisasContext *s, uint32_t insn)
+
+static bool trans_ADR(DisasContext *s, arg_ri *a)
 {
-    unsigned int page, rd;
-    int64_t offset;
+    gen_pc_plus_diff(s, cpu_reg(s, a->rd), a->imm);
+    return true;
+}
 
-    page = extract32(insn, 31, 1);
-    /* SignExtend(immhi:immlo) -> offset */
-    offset = sextract64(insn, 5, 19);
-    offset = offset << 2 | extract32(insn, 29, 2);
-    rd = extract32(insn, 0, 5);
+static bool trans_ADRP(DisasContext *s, arg_ri *a)
+{
+    int64_t offset = (int64_t)a->imm << 12;
 
-    if (page) {
-        /* ADRP (page based) */
-        offset <<= 12;
-        /* The page offset is ok for CF_PCREL. */
-        offset -= s->pc_curr & 0xfff;
-    }
-
-    gen_pc_plus_diff(s, cpu_reg(s, rd), offset);
+    /* The page offset is ok for CF_PCREL. */
+    offset -= s->pc_curr & 0xfff;
+    gen_pc_plus_diff(s, cpu_reg(s, a->rd), offset);
+    return true;
 }
 
 /*
@@ -4656,9 +4649,6 @@ 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 0x20: case 0x21: /* PC-rel. addressing */
-        disas_pc_rel_adr(s, insn);
-        break;
     case 0x22: /* Add/subtract (immediate) */
         disas_add_sub_imm(s, insn);
         break;
-- 
2.34.1