target-arm: Translate with condexec bits from TB flags, not CPUState

When translating, the condexec bits for the TB are in the TB flags;
the CPUState condexec bits may be different.

This patch fixes https://bugs.launchpad.net/bugs/604872 where we might
segfault if we took an exception in the middle of a TB with an IT
block, because when we came to retranslate in cpu_restore_state()
the CPUState condexec bits would have advanced compared to the start
of the TB and we would generate different (wrong) code.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

diff --git a/target-arm/translate.c b/target-arm/translate.c
index 45f8e3e8a357e2ad0fa157f8c267b19b89095828..0e28ffd2901cdca79f7600994ca64085d3d4a854 100644 (file)
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -9096,8 +9096,8 @@ static inline void gen_intermediate_code_internal(CPUState *env,
     dc->singlestep_enabled = env->singlestep_enabled;
     dc->condjmp = 0;
     dc->thumb = ARM_TBFLAG_THUMB(tb->flags);
-    dc->condexec_mask = (env->condexec_bits & 0xf) << 1;
-    dc->condexec_cond = env->condexec_bits >> 4;
+    dc->condexec_mask = (ARM_TBFLAG_CONDEXEC(tb->flags) & 0xf) << 1;
+    dc->condexec_cond = ARM_TBFLAG_CONDEXEC(tb->flags) >> 4;
 #if !defined(CONFIG_USER_ONLY)
     if (IS_M(env)) {
         dc->user = ((env->v7m.exception == 0) && (env->v7m.control & 1));
@@ -9126,7 +9126,7 @@ static inline void gen_intermediate_code_internal(CPUState *env,
     gen_icount_start();
     /* Reset the conditional execution bits immediately. This avoids
        complications trying to do it at the end of the block.  */
-    if (env->condexec_bits)
+    if (dc->condexec_mask || dc->condexec_cond)
       {
         TCGv tmp = new_tmp();
         tcg_gen_movi_i32(tmp, 0);