target/arm: Add PAuth active bit to tbflags

There are 5 bits of state that could be added, but to save
space within tbflags, add only a single enable bit.
Helpers will determine the rest of the state at runtime.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20190108223129.5570-4-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 19 insertions, 0 deletions

diff --git a/target/arm/helper.c b/target/arm/helper.c
index 9bf8fbd8f9..caea722c9b 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -12983,6 +12983,25 @@ void cpu_get_tb_cpu_state(CPUARMState *env, target_ulong *pc,
             flags = FIELD_DP32(flags, TBFLAG_A64, SVEEXC_EL, sve_el);
             flags = FIELD_DP32(flags, TBFLAG_A64, ZCR_LEN, zcr_len);
         }
+
+        if (cpu_isar_feature(aa64_pauth, cpu)) {
+            /*
+             * In order to save space in flags, we record only whether
+             * pauth is "inactive", meaning all insns are implemented as
+             * a nop, or "active" when some action must be performed.
+             * The decision of which action to take is left to a helper.
+             */
+            uint64_t sctlr;
+            if (current_el == 0) {
+                /* FIXME: ARMv8.1-VHE S2 translation regime.  */
+                sctlr = env->cp15.sctlr_el[1];
+            } else {
+                sctlr = env->cp15.sctlr_el[current_el];
+            }
+            if (sctlr & (SCTLR_EnIA | SCTLR_EnIB | SCTLR_EnDA | SCTLR_EnDB)) {
+                flags = FIELD_DP32(flags, TBFLAG_A64, PAUTH_ACTIVE, 1);
+            }
+        }
     } else {
         *pc = env->regs[15];
         flags = FIELD_DP32(flags, TBFLAG_A32, THUMB, env->thumb);