Fix Random_nextState intrinsic on ARM.

runtime/vm/intrinsifier_arm.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"  // Needed here to get TARGET_ARCH_ARM.
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/intrinsifier.h"
 
 #include "vm/assembler.h"
@@ skipping 1384 matching lines @@
   const int64_t disp_0 =
       FlowGraphCompiler::DataOffsetFor(kTypedDataUint32ArrayCid);
 
   const int64_t disp_1 =
       FlowGraphCompiler::ElementSizeFor(kTypedDataUint32ArrayCid) +
       FlowGraphCompiler::DataOffsetFor(kTypedDataUint32ArrayCid);
 
   __ LoadImmediate(R0, a_int32_value);
   __ LoadFromOffset(kLoadWord, R2, R1, disp_0 - kHeapObjectTag);
   __ LoadFromOffset(kLoadWord, R3, R1, disp_1 - kHeapObjectTag);
-  __ mov(R6, ShifterOperand(R3, ASR, 31));  // Sign extend into R6.
-  // 64-bit multiply and accumulate into R6:R3.
-  __ smlal(R3, R6, R0, R2);  // R6:R3 <- R6:R3 + R0 * R2.
+  __ mov(R6, ShifterOperand(0));  // Zero extend unsigned _state[kSTATE_HI].
+  // Unsigned 32-bit multiply and 64-bit accumulate into R6:R3.
+  __ umlal(R3, R6, R0, R2);  // R6:R3 <- R6:R3 + R0 * R2.
   __ StoreToOffset(kStoreWord, R3, R1, disp_0 - kHeapObjectTag);
   __ StoreToOffset(kStoreWord, R6, R1, disp_1 - kHeapObjectTag);
   __ Ret();
   return true;
 }
 
 
 bool Intrinsifier::Object_equal(Assembler* assembler) {
   __ ldr(R0, Address(SP, 0 * kWordSize));
   __ ldr(R1, Address(SP, 1 * kWordSize));
@@ skipping 279 matching lines @@
   __ Bind(&ok);
   __ Ret();
 
   __ Bind(&fall_through);
   return false;
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM