[turbofan] Add basic support for calling to (a subset of) C functions.

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/base/utils/random-number-generator.h"
@@ skipping 5120 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);
   }
 }
 
+
+#if !USE_SIMULATOR
+
+namespace {
+
+int32_t const kMagicFoo0 = 0xdeadbeef;
+
+
+int32_t foo0() { return kMagicFoo0; }
+
+
+int32_t foo1(int32_t x) { return x; }
+
+
+int32_t foo2(int32_t x, int32_t y) { return x - y; }
+
+
+int32_t foo8(int32_t a, int32_t b, int32_t c, int32_t d, int32_t e, int32_t f,
+             int32_t g, int32_t h) {
+  return a + b + c + d + e + f + g + h;

[Sven Panne, 2015/06/25 08:35:09]

Using a non-commutative and non-associative operation would be more helpful
here: Permuted arguments can't be detected with "+".

+}
+
+}  // namespace
+
+
+TEST(RunCallCFunction0) {
+  auto* foo0_ptr = &foo0;
+  RawMachineAssemblerTester<int32_t> m;
+  Node* function = m.LoadFromPointer(&foo0_ptr, kMachPtr);
+  m.Return(m.CallCFunction0(kMachInt32, function));
+  CHECK_EQ(kMagicFoo0, m.Call());
+}
+
+
+TEST(RunCallCFunction1) {
+  auto* foo1_ptr = &foo1;
+  RawMachineAssemblerTester<int32_t> m(kMachInt32);
+  Node* function = m.LoadFromPointer(&foo1_ptr, kMachPtr);
+  m.Return(m.CallCFunction1(kMachInt32, kMachInt32, function, m.Parameter(0)));
+  FOR_INT32_INPUTS(i) {
+    int32_t const expected = *i;
+    CHECK_EQ(expected, m.Call(expected));
+  }
+}
+
+
+TEST(RunCallCFunction2) {
+  auto* foo2_ptr = &foo2;
+  RawMachineAssemblerTester<int32_t> m(kMachInt32, kMachInt32);
+  Node* function = m.LoadFromPointer(&foo2_ptr, kMachPtr);
+  m.Return(m.CallCFunction2(kMachInt32, kMachInt32, kMachInt32, function,
+                            m.Parameter(0), m.Parameter(1)));
+  FOR_INT32_INPUTS(i) {
+    int32_t const x = *i;
+    FOR_INT32_INPUTS(j) {
+      int32_t const y = *j;
+      CHECK_EQ(x - y, m.Call(x, y));
+    }
+  }
+}
+
+
+TEST(RunCallCFunction8) {
+  auto* foo8_ptr = &foo8;
+  RawMachineAssemblerTester<int32_t> m(kMachInt32);
+  Node* function = m.LoadFromPointer(&foo8_ptr, kMachPtr);
+  Node* param = m.Parameter(0);
+  m.Return(m.CallCFunction8(kMachInt32, kMachInt32, kMachInt32, kMachInt32,
+                            kMachInt32, kMachInt32, kMachInt32, kMachInt32,
+                            kMachInt32, function, param, param, param, param,

[Sven Panne, 2015/06/25 08:35:09]

Using the same actual parameter for all formal parameters might disguise bugs,
e.g. accidentally duplicating/leaving out/permuting args.

+                            param, param, param, param));
+  FOR_INT32_INPUTS(i) {
+    int32_t const x = *i;
+    CHECK_EQ(x * 8, m.Call(x));
+  }
+}
+
+#endif  // USE_SIMULATOR
+
 #endif  // V8_TURBOFAN_TARGET