x64 support for d-to-i (truncated)

test/cctest/test-code-stubs.cc

Index: test/cctest/test-code-stubs.cc
diff --git a/test/mjsunit/double-truncation.js b/test/cctest/test-code-stubs.cc
similarity index 54%
copy from test/mjsunit/double-truncation.js
copy to test/cctest/test-code-stubs.cc
index b43e1e6c6353ae0497667312fc6956b08148efa2..405069626bec4d076173f9a1441b62b3554e0498 100644
--- a/test/mjsunit/double-truncation.js
+++ b/test/cctest/test-code-stubs.cc
@@ -1,4 +1,4 @@
-// Copyright 2012 the V8 project authors. All rights reserved.
+// Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -25,14 +25,68 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Flags: --allow-natives-syntax
+#include <stdlib.h>
 
-function RunOneTruncationTest(a, b) {
-  var temp = a | 0;
-  assertEquals(b, temp);
+#include <limits>
+
+#include "v8.h"
+
+#include "cctest.h"
+#include "code-stubs.h"
+#include "test-code-stubs.h"
+#include "factory.h"
+#include "macro-assembler.h"
+#include "platform.h"
+
+using namespace v8::internal;
+
+
+int STDCALL ConvertDToICVersion(double d) {
+  Address double_ptr = reinterpret_cast<Address>(&d);
+  uint32_t exponent_bits = Memory::uint32_at(double_ptr + kDoubleSize / 2);
+  int32_t shifted_mask = static_cast<int32_t>(Double::kExponentMask >> 32);
+  int32_t exponent = (((exponent_bits & shifted_mask) >>
+                       (Double::kPhysicalSignificandSize - 32)) -
+                      HeapNumber::kExponentBias);
+  uint32_t unsigned_exponent = static_cast<uint32_t>(exponent);
+  int result = 0;
+  uint32_t max_exponent =
+    static_cast<uint32_t>(Double::kPhysicalSignificandSize);
+  if (unsigned_exponent >= max_exponent) {
+    if ((exponent - Double::kPhysicalSignificandSize) < 32) {
+      result = Memory::uint32_at(double_ptr) <<
+        (exponent - Double::kPhysicalSignificandSize);
+    }
+  } else {
+    uint64_t big_result =
+        (BitCast<uint64_t>(d) & Double::kSignificandMask) | Double::kHiddenBit;
+    big_result = big_result >> (Double::kPhysicalSignificandSize - exponent);
+    result = static_cast<uint32_t>(big_result);
+  }
+  if (static_cast<int32_t>(exponent_bits) < 0) {
+    return (0 - result);
+  } else {
+    return result;
+  }
 }
 
-function RunAllTruncationTests() {
+
+void RunOneTruncationTestWithTest(ConvertDToIFunc func,
+                                  double from,
+                                  double raw) {
+  uint64_t to = static_cast<int64_t>(raw);
+  int result = (*func)(from);
+  CHECK_EQ(static_cast<int>(to), result);
+}
+
+
+// #define NaN and Infinity so that it's possible to cut-and-paste these tests
+// directly to a .js file and run them.
+#define NaN (OS::nan_value())
+#define Infinity (std::numeric_limits<double>::infinity())
+#define RunOneTruncationTest(p1, p2) RunOneTruncationTestWithTest(func, p1, p2)
+
+void RunAllTruncationTests(ConvertDToIFunc func) {
   RunOneTruncationTest(0, 0);
   RunOneTruncationTest(0.5, 0);
   RunOneTruncationTest(-0.5, 0);
@@ -65,14 +119,12 @@ function RunAllTruncationTests() {
   RunOneTruncationTest(4.8357078901445341e+24, -1073741824);
   RunOneTruncationTest(-4.8357078901445341e+24, 1073741824);
 
-  RunOneTruncationTest(9.6714111686030497e+24, -2147483648);
-  RunOneTruncationTest(-9.6714111686030497e+24, -2147483648);
-  RunOneTruncationTest(9.6714157802890681e+24, -2147483648);
-  RunOneTruncationTest(-9.6714157802890681e+24, -2147483648);
+  RunOneTruncationTest(9.6714111686030497e+24, -2147483648.0);
+  RunOneTruncationTest(-9.6714111686030497e+24, -2147483648.0);
+  RunOneTruncationTest(9.6714157802890681e+24, -2147483648.0);
+  RunOneTruncationTest(-9.6714157802890681e+24, -2147483648.0);
 }
 
-RunAllTruncationTests();
-RunAllTruncationTests();
-%OptimizeFunctionOnNextCall(RunOneTruncationTest);
-RunAllTruncationTests();
-RunAllTruncationTests();
+#undef NaN
+#undef Infinity
+#undef RunOneTruncationTest