[PATCH 16/20] target/arm: Convert load (pointer auth) insns to decodetree

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

Convert the instructions in the load/store register (pointer
authentication) group ot decodetree: LDRAA, LDRAB.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/arm/tcg/a64.decode      |  7 +++
 target/arm/tcg/translate-a64.c | 83 +++++++---------------------------
 2 files changed, 23 insertions(+), 67 deletions(-)

diff --git a/target/arm/tcg/a64.decode b/target/arm/tcg/a64.decode
index 69635586718..2ea85312bba 100644
--- a/target/arm/tcg/a64.decode
+++ b/target/arm/tcg/a64.decode
@@ -457,3 +457,10 @@ LDUMIN          .. 111 0 00 . . 1 ..... 0111 00 ..... ..... @atomic
 SWP             .. 111 0 00 . . 1 ..... 1000 00 ..... ..... @atomic
 
 LDAPR           sz:2 111 0 00 1 0 1 11111 1100 00 rn:5 rt:5
+
+# Load/store register (pointer authentication)
+
+# LDRA immediate is 10 bits signed and scaled, but the bits aren't all contiguous
+%ldra_imm       22:s1 12:9 !function=times_2
+
+LDRA            11 111 0 00 m:1 . 1 ......... w:1 1 rn:5 rt:5 imm=%ldra_imm
diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index 4e3bebab8e0..10a6fc4efb7 100644
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -3150,42 +3150,22 @@ static bool trans_LDAPR(DisasContext *s, arg_LDAPR *a)
     return true;
 }
 
-/*
- * PAC memory operations
- *
- *  31  30      27  26    24    22  21       12  11  10    5     0
- * +------+-------+---+-----+-----+---+--------+---+---+----+-----+
- * | size | 1 1 1 | V | 0 0 | M S | 1 |  imm9  | W | 1 | Rn |  Rt |
- * +------+-------+---+-----+-----+---+--------+---+---+----+-----+
- *
- * Rt: the result register
- * Rn: base address or SP
- * V: vector flag (always 0 as of v8.3)
- * M: clear for key DA, set for key DB
- * W: pre-indexing flag
- * S: sign for imm9.
- */
-static void disas_ldst_pac(DisasContext *s, uint32_t insn,
-                           int size, int rt, bool is_vector)
+static bool trans_LDRA(DisasContext *s, arg_LDRA *a)
 {
-    int rn = extract32(insn, 5, 5);
-    bool is_wback = extract32(insn, 11, 1);
-    bool use_key_a = !extract32(insn, 23, 1);
-    int offset;
     TCGv_i64 clean_addr, dirty_addr, tcg_rt;
 
-    if (size != 3 || is_vector || !dc_isar_feature(aa64_pauth, s)) {
-        unallocated_encoding(s);
-        return;
+    /* Load with pointer authentication */
+    if (!dc_isar_feature(aa64_pauth, s)) {
+        return false;
     }
 
-    if (rn == 31) {
+    if (a->rn == 31) {
         gen_check_sp_alignment(s);
     }
-    dirty_addr = read_cpu_reg_sp(s, rn, 1);
+    dirty_addr = read_cpu_reg_sp(s, a->rn, 1);
 
     if (s->pauth_active) {
-        if (use_key_a) {
+        if (!a->m) {
             gen_helper_autda(dirty_addr, cpu_env, dirty_addr,
                              tcg_constant_i64(0));
         } else {
@@ -3194,23 +3174,21 @@ static void disas_ldst_pac(DisasContext *s, uint32_t insn,
         }
     }
 
-    /* Form the 10-bit signed, scaled offset.  */
-    offset = (extract32(insn, 22, 1) << 9) | extract32(insn, 12, 9);
-    offset = sextract32(offset << size, 0, 10 + size);
-    tcg_gen_addi_i64(dirty_addr, dirty_addr, offset);
+    tcg_gen_addi_i64(dirty_addr, dirty_addr, a->imm);
 
     /* Note that "clean" and "dirty" here refer to TBI not PAC.  */
     clean_addr = gen_mte_check1(s, dirty_addr, false,
-                                is_wback || rn != 31, size);
+                                a->w || a->rn != 31, 3);
 
-    tcg_rt = cpu_reg(s, rt);
-    do_gpr_ld(s, tcg_rt, clean_addr, size,
-              /* extend */ false, /* iss_valid */ !is_wback,
-              /* iss_srt */ rt, /* iss_sf */ true, /* iss_ar */ false);
+    tcg_rt = cpu_reg(s, a->rt);
+    do_gpr_ld(s, tcg_rt, clean_addr, 3,
+              /* extend */ false, /* iss_valid */ !a->w,
+              /* iss_srt */ a->rt, /* iss_sf */ true, /* iss_ar */ false);
 
-    if (is_wback) {
-        tcg_gen_mov_i64(cpu_reg_sp(s, rn), dirty_addr);
+    if (a->w) {
+        tcg_gen_mov_i64(cpu_reg_sp(s, a->rn), dirty_addr);
     }
+    return true;
 }
 
 /*
@@ -3298,31 +3276,6 @@ static void disas_ldst_ldapr_stlr(DisasContext *s, uint32_t insn)
     }
 }
 
-/* Load/store register (all forms) */
-static void disas_ldst_reg(DisasContext *s, uint32_t insn)
-{
-    int rt = extract32(insn, 0, 5);
-    bool is_vector = extract32(insn, 26, 1);
-    int size = extract32(insn, 30, 2);
-
-    switch (extract32(insn, 24, 2)) {
-    case 0:
-        if (extract32(insn, 21, 1) == 0) {
-            break;
-        }
-        switch (extract32(insn, 10, 2)) {
-        case 0:
-        case 2:
-            break;
-        default:
-            disas_ldst_pac(s, insn, size, rt, is_vector);
-            return;
-        }
-        break;
-    }
-    unallocated_encoding(s);
-}
-
 /* AdvSIMD load/store multiple structures
  *
  *  31  30  29           23 22  21         16 15    12 11  10 9    5 4    0
@@ -3832,10 +3785,6 @@ static void disas_ldst_tag(DisasContext *s, uint32_t insn)
 static void disas_ldst(DisasContext *s, uint32_t insn)
 {
     switch (extract32(insn, 24, 6)) {
-    case 0x38: case 0x39:
-    case 0x3c: case 0x3d: /* Load/store register (all forms) */
-        disas_ldst_reg(s, insn);
-        break;
     case 0x0c: /* AdvSIMD load/store multiple structures */
         disas_ldst_multiple_struct(s, insn);
         break;
-- 
2.34.1