target/arm: Load gcs record for RET

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20251008215613.300150-59-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index 9c3de0cf71771867076777295579eb67088429b0..dfd5b17831759fa2b7d29baf917120cf511f5646 100644 (file)
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -444,6 +444,27 @@ static void gen_add_gcs_record(DisasContext *s, TCGv_i64 value)
     tcg_gen_mov_i64(gcspr, addr);
 }
 
+static void gen_load_check_gcs_record(DisasContext *s, TCGv_i64 target,
+                                      GCSInstructionType it, int rt)
+{
+    TCGv_i64 gcspr = cpu_gcspr[s->current_el];
+    int mmuidx = core_gcs_mem_index(s->mmu_idx);
+    MemOp mop = finalize_memop(s, MO_64 | MO_ALIGN);
+    TCGv_i64 rec_va = tcg_temp_new_i64();
+
+    tcg_gen_qemu_ld_i64(rec_va, clean_data_tbi(s, gcspr), mmuidx, mop);
+
+    if (s->gcs_rvcen) {
+        TCGLabel *fail_label =
+            delay_exception(s, EXCP_UDEF, syn_gcs_data_check(it, rt));
+
+        tcg_gen_brcond_i64(TCG_COND_NE, rec_va, target, fail_label);
+    }
+
+    gen_a64_set_pc(s, rec_va);
+    tcg_gen_addi_i64(gcspr, gcspr, 8);
+}
+
 typedef struct DisasCompare64 {
     TCGCond cond;
     TCGv_i64 value;
@@ -1798,7 +1819,13 @@ static bool trans_BLR(DisasContext *s, arg_r *a)
 
 static bool trans_RET(DisasContext *s, arg_r *a)
 {
-    gen_a64_set_pc(s, cpu_reg(s, a->rn));
+    TCGv_i64 target = cpu_reg(s, a->rn);
+
+    if (s->gcs_en) {
+        gen_load_check_gcs_record(s, target, GCS_IT_RET_nPauth, a->rn);
+    } else {
+        gen_a64_set_pc(s, target);
+    }
     s->base.is_jmp = DISAS_JUMP;
     return true;
 }