When PSTATE.ALLINT is set, an IRQ or FIQ interrupt that is targeted to
ELx, with or without superpriority is masked. As Richard suggested, place
ALLINT bit in PSTATE in env->pstate.

In the pseudocode, AArch64.ExceptionReturn() calls SetPSTATEFromPSR(), which
treats PSTATE.ALLINT as one of the bits which are reinstated from SPSR to
PSTATE regardless of whether this is an illegal exception return or not. So
handle PSTATE.ALLINT the same way as PSTATE.DAIF in the illegal_return exit
path of the exception_return helper. With the change, exception entry and
return are automatically handled.

Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
---
v13:
- Handle PSTATE.ALLINT the same way as PSTATE.DAIF in the illegal_return
  exit path.
- Update the commit message.
- Add Reviewed-by.
v5:
- Remove the ALLINT comment, as it is covered by "all other bits".
- Add Reviewed-by.
v4:
- Keep PSTATE.ALLINT in env->pstate but not env->allint.
- Update the commit message.
v3:
- Remove ALLINT dump in aarch64_cpu_dump_state().
- Update the commit message.
---
 target/arm/cpu.h            | 1 +
 target/arm/tcg/helper-a64.c | 4 ++--
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index bc0c84873f..de740d223f 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -1430,6 +1430,7 @@ void pmu_init(ARMCPU *cpu);
 #define PSTATE_D (1U << 9)
 #define PSTATE_BTYPE (3U << 10)
 #define PSTATE_SSBS (1U << 12)
+#define PSTATE_ALLINT (1U << 13)
 #define PSTATE_IL (1U << 20)
 #define PSTATE_SS (1U << 21)
 #define PSTATE_PAN (1U << 22)
diff --git a/target/arm/tcg/helper-a64.c b/target/arm/tcg/helper-a64.c
index ebaa7f00df..29f3ef274a 100644
--- a/target/arm/tcg/helper-a64.c
+++ b/target/arm/tcg/helper-a64.c
@@ -892,8 +892,8 @@ illegal_return:
      */
     env->pstate |= PSTATE_IL;
     env->pc = new_pc;
-    spsr &= PSTATE_NZCV | PSTATE_DAIF;
-    spsr |= pstate_read(env) & ~(PSTATE_NZCV | PSTATE_DAIF);
+    spsr &= PSTATE_NZCV | PSTATE_DAIF | PSTATE_ALLINT;
+    spsr |= pstate_read(env) & ~(PSTATE_NZCV | PSTATE_DAIF | PSTATE_ALLINT);
     pstate_write(env, spsr);
     if (!arm_singlestep_active(env)) {
         env->pstate &= ~PSTATE_SS;
-- 
2.34.1