[turbofan] Optimize certain chains of Branch into a Switch.

test/unittests/compiler/node-test-utils.h

Index: test/unittests/compiler/node-test-utils.h
diff --git a/test/unittests/compiler/node-test-utils.h b/test/unittests/compiler/node-test-utils.h
index 99187e4cfc27d24a6ed8416a572be7b1321e4371..03011972b7c151672f32f5481e8af4880495c0b2 100644
--- a/test/unittests/compiler/node-test-utils.h
+++ b/test/unittests/compiler/node-test-utils.h
@@ -37,6 +37,9 @@ Matcher<Node*> IsBranch(const Matcher<Node*>& value_matcher,
                         const Matcher<Node*>& control_matcher);
 Matcher<Node*> IsMerge(const Matcher<Node*>& control0_matcher,
                        const Matcher<Node*>& control1_matcher);
+Matcher<Node*> IsMerge(const Matcher<Node*>& control0_matcher,
+                       const Matcher<Node*>& control1_matcher,
+                       const Matcher<Node*>& control2_matcher);
 Matcher<Node*> IsLoop(const Matcher<Node*>& control0_matcher,
                       const Matcher<Node*>& control1_matcher);
 Matcher<Node*> IsLoop(const Matcher<Node*>& control0_matcher,
@@ -44,6 +47,11 @@ Matcher<Node*> IsLoop(const Matcher<Node*>& control0_matcher,
                       const Matcher<Node*>& control2_matcher);
 Matcher<Node*> IsIfTrue(const Matcher<Node*>& control_matcher);
 Matcher<Node*> IsIfFalse(const Matcher<Node*>& control_matcher);
+Matcher<Node*> IsSwitch(const Matcher<Node*>& value_matcher,
+                        const Matcher<Node*>& control_matcher);
+Matcher<Node*> IsIfValue(const Matcher<int32_t>& value_matcher,
+                         const Matcher<Node*>& control_matcher);
+Matcher<Node*> IsIfDefault(const Matcher<Node*>& control_matcher);
 Matcher<Node*> IsValueEffect(const Matcher<Node*>& value_matcher);
 Matcher<Node*> IsFinish(const Matcher<Node*>& value_matcher,
                         const Matcher<Node*>& effect_matcher);