Revert of Reland: Remove register index/code indirection

test/cctest/test-code-stubs-arm.cc

Index: test/cctest/test-code-stubs-arm.cc
diff --git a/test/cctest/test-code-stubs-arm.cc b/test/cctest/test-code-stubs-arm.cc
index 385718f486c9cd037c03b2cb4fd56d35029e0373..a9856f5245be031a10ccf121a966b1ac178d99ec 100644
--- a/test/cctest/test-code-stubs-arm.cc
+++ b/test/cctest/test-code-stubs-arm.cc
@@ -76,13 +76,11 @@
   // Save registers make sure they don't get clobbered.
   int source_reg_offset = kDoubleSize;
   int reg_num = 0;
-  for (; reg_num < Register::kNumRegisters; ++reg_num) {
+  for (; reg_num < Register::NumAllocatableRegisters(); ++reg_num) {
     Register reg = Register::from_code(reg_num);
-    if (reg.IsAllocatable()) {
-      if (!reg.is(destination_reg)) {
-        __ push(reg);
-        source_reg_offset += kPointerSize;
-      }
+    if (!reg.is(destination_reg)) {
+      __ push(reg);
+      source_reg_offset += kPointerSize;
     }
   }
 
@@ -107,13 +105,11 @@
   // Make sure no registers have been unexpectedly clobbered
   for (--reg_num; reg_num >= 0; --reg_num) {
     Register reg = Register::from_code(reg_num);
-    if (reg.IsAllocatable()) {
-      if (!reg.is(destination_reg)) {
-        __ ldr(ip, MemOperand(sp, 0));
-        __ cmp(reg, ip);
-        __ Assert(eq, kRegisterWasClobbered);
-        __ add(sp, sp, Operand(kPointerSize));
-      }
+    if (!reg.is(destination_reg)) {
+      __ ldr(ip, MemOperand(sp, 0));
+      __ cmp(reg, ip);
+      __ Assert(eq, kRegisterWasClobbered);
+      __ add(sp, sp, Operand(kPointerSize));
     }
   }