target/arm: Rebuild hflags at MSR writes

Continue setting, but not relying upon, env->hflags.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20191023150057.25731-18-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 34 insertions, 7 deletions

diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 2d6cd09..d4bebbe 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -1789,8 +1789,17 @@ static void handle_sys(DisasContext *s, uint32_t insn, bool isread,
     if ((tb_cflags(s->base.tb) & CF_USE_ICOUNT) && (ri->type & ARM_CP_IO)) {
         /* I/O operations must end the TB here (whether read or write) */
         s->base.is_jmp = DISAS_UPDATE;
-    } else if (!isread && !(ri->type & ARM_CP_SUPPRESS_TB_END)) {
-        /* We default to ending the TB on a coprocessor register write,
+    }
+    if (!isread && !(ri->type & ARM_CP_SUPPRESS_TB_END)) {
+        /*
+         * A write to any coprocessor regiser that ends a TB
+         * must rebuild the hflags for the next TB.
+         */
+        TCGv_i32 tcg_el = tcg_const_i32(s->current_el);
+        gen_helper_rebuild_hflags_a64(cpu_env, tcg_el);
+        tcg_temp_free_i32(tcg_el);
+        /*
+         * We default to ending the TB on a coprocessor register write,
          * but allow this to be suppressed by the register definition
          * (usually only necessary to work around guest bugs).
          */
diff --git a/target/arm/translate.c b/target/arm/translate.c
index 9634052..46a0bf5 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -6890,6 +6890,8 @@ static int disas_coproc_insn(DisasContext *s, uint32_t insn)
     ri = get_arm_cp_reginfo(s->cp_regs,
             ENCODE_CP_REG(cpnum, is64, s->ns, crn, crm, opc1, opc2));
     if (ri) {
+        bool need_exit_tb;
+
         /* Check access permissions */
         if (!cp_access_ok(s->current_el, ri, isread)) {
             return 1;
@@ -7068,14 +7070,30 @@ static int disas_coproc_insn(DisasContext *s, uint32_t insn)
             }
         }
 
-        if ((tb_cflags(s->base.tb) & CF_USE_ICOUNT) && (ri->type & ARM_CP_IO)) {
-            /* I/O operations must end the TB here (whether read or write) */
-            gen_lookup_tb(s);
-        } else if (!isread && !(ri->type & ARM_CP_SUPPRESS_TB_END)) {
-            /* We default to ending the TB on a coprocessor register write,
+        /* I/O operations must end the TB here (whether read or write) */
+        need_exit_tb = ((tb_cflags(s->base.tb) & CF_USE_ICOUNT) &&
+                        (ri->type & ARM_CP_IO));
+
+        if (!isread && !(ri->type & ARM_CP_SUPPRESS_TB_END)) {
+            /*
+             * A write to any coprocessor regiser that ends a TB
+             * must rebuild the hflags for the next TB.
+             */
+            TCGv_i32 tcg_el = tcg_const_i32(s->current_el);
+            if (arm_dc_feature(s, ARM_FEATURE_M)) {
+                gen_helper_rebuild_hflags_m32(cpu_env, tcg_el);
+            } else {
+                gen_helper_rebuild_hflags_a32(cpu_env, tcg_el);
+            }
+            tcg_temp_free_i32(tcg_el);
+            /*
+             * We default to ending the TB on a coprocessor register write,
              * but allow this to be suppressed by the register definition
              * (usually only necessary to work around guest bugs).
              */
+            need_exit_tb = true;
+        }
+        if (need_exit_tb) {
             gen_lookup_tb(s);
         }