Index: llvm/trunk/utils/update_llc_test_checks.py
===================================================================
--- llvm/trunk/utils/update_llc_test_checks.py
+++ llvm/trunk/utils/update_llc_test_checks.py
@@ -222,8 +222,15 @@
         triple_in_ir = m.groups()[0]
         break
 
-    run_lines = [m.group(1)
+    raw_lines = [m.group(1)
                  for m in [RUN_LINE_RE.match(l) for l in input_lines] if m]
+    run_lines = [raw_lines[0]] if len(raw_lines) > 0 else []
+    for l in raw_lines[1:]:
+        if run_lines[-1].endswith("\\"):
+            run_lines[-1] = run_lines[-1].rstrip("\\") + " " + l
+        else:
+            run_lines.append(l)
+
     if args.verbose:
       print >>sys.stderr, 'Found %d RUN lines:' % (len(run_lines),)
       for l in run_lines:
Index: llvm/trunk/utils/update_test_checks.py
===================================================================
--- llvm/trunk/utils/update_test_checks.py
+++ llvm/trunk/utils/update_test_checks.py
@@ -292,8 +292,15 @@
     with open(test) as f:
       input_lines = [l.rstrip() for l in f]
 
-    run_lines = [m.group(1)
+    raw_lines = [m.group(1)
                  for m in [RUN_LINE_RE.match(l) for l in input_lines] if m]
+    run_lines = [raw_lines[0]] if len(raw_lines) > 0 else []
+    for l in raw_lines[1:]:
+        if run_lines[-1].endswith("\\"):
+            run_lines[-1] = run_lines[-1].rstrip("\\") + " " + l
+        else:
+            run_lines.append(l)
+
     if args.verbose:
       print >>sys.stderr, 'Found %d RUN lines:' % (len(run_lines),)
       for l in run_lines: