Implement Smi_bitLength intrinsic on mips, arm, and arm64.

runtime/vm/assembler_arm64_test.cc

 // Copyright (c) 2013, 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_ARM64)
 
 #include "vm/assembler.h"
 #include "vm/cpu.h"
 #include "vm/os.h"
@@ skipping 705 matching lines @@
   __ ret();
 }
 
 
 ASSEMBLER_TEST_RUN(EorImm, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
 }
 
 
+ASSEMBLER_TEST_GENERATE(Clz, assembler) {
+  Label error;
+
+  __ clz(R1, ZR);
+  __ cmp(R1, Operand(64));
+  __ b(&error, NE);
+  __ LoadImmediate(R2, 42, kNoPP);
+  __ clz(R2, R2);
+  __ cmp(R2, Operand(58));
+  __ b(&error, NE);
+  __ LoadImmediate(R0, -1, kNoPP);
+  __ clz(R1, R0);
+  __ cmp(R1, Operand(0));
+  __ b(&error, NE);
+  __ add(R0, ZR, Operand(R0, LSR, 3));
+  __ clz(R1, R0);
+  __ cmp(R1, Operand(3));
+  __ b(&error, NE);
+  __ mov(R0, ZR);
+  __ ret();
+  __ Bind(&error);
+  __ LoadImmediate(R0, 1, kNoPP);
+  __ ret();
+}
+
+
+ASSEMBLER_TEST_RUN(Clz, test) {
+  typedef int64_t (*Int64Return)() DART_UNUSED;
+  EXPECT_EQ(0, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+}
+
+
 // Comparisons, branching.
 ASSEMBLER_TEST_GENERATE(BranchALForward, assembler) {
   Label l;
   __ movz(R0, Immediate(42), 0);
   __ b(&l, AL);
   __ movz(R0, Immediate(0), 0);
   __ Bind(&l);
   __ ret();
 }
 
@@ skipping 2859 matching lines @@
 
   EXPECT_EQ(-1, RANGE_OF(Bool::True().raw()));
 
 #undef RANGE_OF
 }
 
 
 }  // namespace dart
 
 #endif  // defined(TARGET_ARCH_ARM64)