Adds muls, sdiv, udiv instructions to ARM simulator, assembler, disassembler

runtime/vm/simulator_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 <math.h>  // for isnan.
 #include <setjmp.h>
 #include <stdlib.h>
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_ARM)
@@ skipping 1978 matching lines @@
       if (instr->HasL()) {
         set_register(rd, ReadW(addr, instr));
       } else {
         WriteW(addr, get_register(rd), instr);
       }
     }
   }
 }
 
 
+void Simulator::DoDivision(Instr* instr) {
+  ASSERT(CPUFeatures::integer_division_supported());
+  Register rd = instr->RdField();
+  Register rn = instr->RnField();
+  Register rm = instr->RmField();
+
+  // TODO(zra): Does the hardware trap on divide-by-zero?
+  //     Revisit when we test on ARM hardware.
+  if (get_register(rm) == 0) {
+    set_register(rd, 0);
+    return;
+  }
+
+  if (instr->Bit(21) == 1) {
+    // unsigned division.
+    uint32_t rn_val = static_cast<uint32_t>(get_register(rn));
+    uint32_t rm_val = static_cast<uint32_t>(get_register(rm));
+    uint32_t result = rn_val / rm_val;
+    set_register(rd, static_cast<int32_t>(result));
+  } else {
+    // signed division.
+    int32_t rn_val = get_register(rn);
+    int32_t rm_val = get_register(rm);
+    int32_t result;
+    if ((rn_val == static_cast<int32_t>(0x80000000)) &&
+        (rm_val == static_cast<int32_t>(0xffffffff))) {
+      result = 0x80000000;
+    } else {
+      result = rn_val / rm_val;
+    }
+    set_register(rd, result);
+  }
+}
+
+
 void Simulator::DecodeType3(Instr* instr) {
+  if (instr->IsDivision()) {
+    DoDivision(instr);
+    return;
+  }
   Register rd = instr->RdField();
   Register rn = instr->RnField();
   int32_t rn_val = get_register(rn);
   bool shifter_carry_out = 0;
   int32_t shifter_operand = GetShiftRm(instr, &shifter_carry_out);
   uword addr = 0;
   bool write_back = false;
   switch (instr->PUField()) {
     case 0: {
       // Format(instr, "'memop'cond'b 'rd, ['rn], -'shift_rm");
@@ skipping 797 matching lines @@
   // isolate->ChangeStateToGeneratedCode();
   set_register(kExceptionObjectReg, bit_cast<int32_t>(object.raw()));
   buf->Longjmp();
 }
 
 }  // namespace dart
 
 #endif  // !defined(HOST_ARCH_ARM)
 
 #endif  // defined TARGET_ARCH_ARM