test: Add a test case for variable watchpoints

    $ uftrace -W var:mydata tests/t-watch-global
    # DURATION     TID     FUNCTION
                [238314] | __monstartup() {
                [238314] |   /* watch:var (mydata=0) */
       1.375 us [238314] | } /* __monstartup */
       0.384 us [238314] | __cxa_atexit();
                [238314] | main() {
                [238314] |   foo() {
                [238314] |     /* watch:var (mydata=1) */
       0.202 us [238314] |     bar();
                [238314] |     /* watch:var (mydata=2) */
       0.638 us [238314] |   } /* foo */
       0.902 us [238314] | } /* main */

Signed-off-by: Namhyung Kim <namhyung@gmail.com>

tests/s-watch-global.c

@@ -0,0 +1,27 @@
+#include <stdlib.h>
+
+volatile int mydata;
+
+void bar(int n)
+{
+	if (n)
+		mydata = -1;
+}
+
+void foo(int n)
+{
+	mydata = 1;
+	bar(n);
+	mydata = 2;
+}
+
+int main(int argc, char *argv[])
+{
+	int n = 0;
+
+	if (argc > 1)
+		n = atoi(argv[1]);
+
+	foo(n);
+	return 0;
+}

tests/t290_watch_global.py

@@ -0,0 +1,25 @@
+#!/usr/bin/env python3
+
+import re
+
+from runtest import TestBase
+
+class TestCase(TestBase):
+    def __init__(self):
+        TestBase.__init__(self, 'watch-global', result="""
+# DURATION     TID     FUNCTION
+            [243156] | __monstartup() {
+            [243156] |   /* watch:var (mydata=0) */
+   2.803 us [243156] | } /* __monstartup */
+   0.621 us [243156] | __cxa_atexit();
+            [243156] | main() {
+            [243156] |   foo() {
+            [243156] |     /* watch:var (mydata=1) */
+   0.117 us [243156] |     bar();
+            [243156] |     /* watch:var (mydata=2) */
+   0.643 us [243156] |   } /* foo */
+   0.938 us [243156] | } /* main */
+""")
+
+    def setup(self):
+        self.option = '-W var:mydata'