[turbofan] Initial support for Switch.

test/cctest/compiler/test-run-machops.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <cmath>
 #include <functional>
 #include <limits>
 
 #include "src/base/bits.h"
 #include "src/codegen.h"
@@ skipping 429 matching lines @@
   phi->ReplaceInput(1, m.Float64Add(phi, m.Float64Constant(0.5)));
   m.Goto(&header);
 
   m.Bind(end);
   m.Return(m.ChangeFloat64ToInt32(phi));
 
   CHECK_EQ(10, m.Call());
 }
 
 
+TEST(RunSwitch1) {
+  RawMachineAssemblerTester<int32_t> m;
+
+  int constant = 11223344;
+
+  MLabel block0, block1, end;
+  MLabel* cases[] = {&block0, &block1};
+  m.Switch(m.IntPtrConstant(0), cases, arraysize(cases));
+  m.Bind(&block0);
+  m.Goto(&end);
+  m.Bind(&block1);
+  m.Goto(&end);
+  m.Bind(&end);
+  m.Return(m.Int32Constant(constant));
+
+  CHECK_EQ(constant, m.Call());
+}
+
+
+TEST(RunSwitch2) {
+  RawMachineAssemblerTester<int32_t> m(kMachInt32);
+
+  const size_t kNumCases = 255;
+  int32_t values[kNumCases];
+  m.main_isolate()->random_number_generator()->NextBytes(values,
+                                                         sizeof(values));
+  MLabel end;
+  MLabel* cases[kNumCases];
+  Node* results[kNumCases];
+  for (size_t i = 0; i < kNumCases; ++i) {
+    cases[i] = new (m.main_zone()->New(sizeof(MLabel))) MLabel;
+  }
+  m.Switch(m.ConvertInt32ToIntPtr(m.Parameter(0)), cases, arraysize(cases));
+  for (size_t i = 0; i < kNumCases; ++i) {
+    m.Bind(cases[i]);
+    results[i] = m.Int32Constant(values[i]);
+    m.Goto(&end);
+  }
+  m.Bind(&end);
+  const int num_results = static_cast<int>(arraysize(results));
+  Node* phi =
+      m.NewNode(m.common()->Phi(kMachInt32, num_results), num_results, results);
+  m.Return(phi);
+
+  for (size_t i = 0; i < kNumCases; ++i) {
+    CHECK_EQ(values[i], m.Call(static_cast<int>(i)));
+  }
+}
+
+
 TEST(RunLoadInt32) {
   RawMachineAssemblerTester<int32_t> m;
 
   int32_t p1 = 0;  // loads directly from this location.
   m.Return(m.LoadFromPointer(&p1, kMachInt32));
 
   FOR_INT32_INPUTS(i) {
     p1 = *i;
     CHECK_EQ(p1, m.Call());
   }
@@ skipping 4218 matching lines @@
       m.Float64RoundTiesAway(m.LoadFromPointer(&input, kMachFloat64)));
   m.Return(m.Int32Constant(0));
   for (size_t i = 0; i < arraysize(kValues); ++i) {
     input = kValues[i];
     CHECK_EQ(0, m.Call());
     double expected = round(kValues[i]);
     CHECK_EQ(expected, result);
   }
 }
 #endif  // V8_TURBOFAN_TARGET