DR6 single step exception status bit, by Juergen Keil.

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3024 c046a42c-6fe2-441c-8c8c-71466251a162

1 files changed, 6 insertions, 0 deletions

diff --git a/target-i386/helper.c b/target-i386/helper.c
index 951fdc5732..3c051b9ea3 100644
--- a/target-i386/helper.c
+++ b/target-i386/helper.c
@@ -1622,6 +1622,12 @@ void helper_cmpxchg8b(void)
     CC_SRC = eflags;
 }
 
+void helper_single_step()
+{
+    env->dr[6] |= 0x4000;
+    raise_exception(EXCP01_SSTP);
+}
+
 void helper_cpuid(void)
 {
     uint32_t index;