Out-of-line constant pool on Arm: Stage 1 - Free up r7 for use as constant pool pointer register

src/arm/frames-arm.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
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@@ skipping 46 matching lines @@
 // Return the code of the n-th caller-saved register available to JavaScript
 // e.g. JSCallerSavedReg(0) returns r0.code() == 0
 int JSCallerSavedCode(int n);
 
 
 // Callee-saved registers preserved when switching from C to JavaScript
 const RegList kCalleeSaved =
   1 <<  4 |  //  r4 v1
   1 <<  5 |  //  r5 v2
   1 <<  6 |  //  r6 v3
-  1 <<  7 |  //  r7 v4
+  1 <<  7 |  //  r7 v4 (pp in JavaScript code)
   1 <<  8 |  //  r8 v5 (cp in JavaScript code)
   kR9Available <<  9 |  //  r9 v6
   1 << 10 |  // r10 v7
   1 << 11;   // r11 v8 (fp in JavaScript code)
 
 // When calling into C++ (only for C++ calls that can't cause a GC).
 // The call code will take care of lr, fp, etc.
 const RegList kCallerSaved =
   1 <<  0 |  // r0
   1 <<  1 |  // r1
@@ skipping 94 matching lines @@
 
 
 inline void StackHandler::SetFp(Address slot, Address fp) {
   Memory::Address_at(slot) = fp;
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_ARM_FRAMES_ARM_H_