Implement some conditional moves instructions for ia32/x64. Use them in MinMax instruction implemen…

runtime/vm/assembler_x64_test.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/assembler.h"
 #include "vm/os.h"
 #include "vm/unit_test.h"
@@ skipping 2549 matching lines @@
   const char* to = new char[10];
   typedef void (*TestRepMovsBytes)(const char* from, const char* to, int count);
   reinterpret_cast<TestRepMovsBytes>(test->entry())(from, to, 10);
   EXPECT_EQ(to[0], '0');
   for (int i = 0; i < 10; i++) {
     EXPECT_EQ(from[i], to[i]);
   }
   delete [] to;
 }
 
+
+ASSEMBLER_TEST_GENERATE(ConditionalMovesCompare, assembler) {
+  // RDI: Arg0.
+  // RSI: Arg1.
+  __ movq(RDX, Immediate(1));  // Greater equal.
+  __ movq(RCX, Immediate(-1));  // Less
+  __ cmpq(RDI, RSI);
+  __ cmovlessq(RAX, RCX);
+  __ cmovgeq(RAX, RDX);
+  __ ret();
+}
+
+
+ASSEMBLER_TEST_RUN(ConditionalMovesCompare, test) {
+  typedef int (*ConditionalMovesCompareCode)(int i, int i);
+  int res = reinterpret_cast<ConditionalMovesCompareCode>(test->entry())(10, 5);
+  EXPECT_EQ(1, res);  // Greater equal.
+  res = reinterpret_cast<ConditionalMovesCompareCode>(test->entry())(5, 5);
+  EXPECT_EQ(1, res);  // Greater equal.
+  res = reinterpret_cast<ConditionalMovesCompareCode>(test->entry())(2, 5);
+  EXPECT_EQ(-1, res);  // Less.
+}
+
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64