target-alpha: overflow condition for sublv and subqv

The conditions to detect overflow in sub operations was wrong.

This patch is necessary to boot Tru64.

Signed-off-by: Tristan Gingold <gingold@adacore.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7073 c046a42c-6fe2-441c-8c8c-71466251a162

2 files changed, 32 insertions, 0 deletions

diff --git a/tests/alpha/Makefile b/tests/alpha/Makefile
index e4e23d2d08..2b1f03d048 100644
--- a/tests/alpha/Makefile
+++ b/tests/alpha/Makefile
@@ -23,6 +23,9 @@ test-cmov.o: test-cond.c
 test-cmov: test-cmov.o crt.o
 	$(LINK)
 
+test-ovf: test-ovf.o crt.o
+	$(LINK)
+
 check: $(TESTS)
 	for f in $(TESTS); do $(SIM) $$f || exit 1; done
 
diff --git a/tests/alpha/test-ovf.c b/tests/alpha/test-ovf.c
new file mode 100644
index 0000000000..01c80e7525
--- /dev/null
+++ b/tests/alpha/test-ovf.c
@@ -0,0 +1,29 @@
+static long test_subqv (long a, long b)
+{
+  long res;
+
+  asm ("subq/v %1,%2,%0"
+       : "=r" (res) : "r" (a), "r" (b));
+  return res;
+}
+static struct {
+  long (*func)(long, long);
+  long a;
+  long b;
+  long r;
+} vectors[] =
+  {
+    {test_subqv, 0, 0x7d54000, 0xfffffffff82ac000L}
+  };
+
+int main (void)
+{
+  int i;
+
+  for (i = 0; i < sizeof (vectors)/sizeof(vectors[0]); i++)
+    if ((*vectors[i].func)(vectors[i].a, vectors[i].b) != vectors[i].r) {
+      write(1, "Failed\n", 7);
+    }
+  write(1, "OK\n", 3);
+  return 0;
+}