[cleanup] Make Register::reg_code_ private

Subclasses can now access it via {code()}, even in constexpr contexts.

R=tebbi@chromium.org

Bug: v8:9810
Change-Id: I3cc6872f568f38db8cdbcda69ac0e203f839cda5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1914216Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64962}

src/codegen/arm/register-arm.h

@@ -223,7 +223,7 @@ using DoubleRegister = DwVfpRegister;
 class LowDwVfpRegister
     : public RegisterBase<LowDwVfpRegister, kDoubleCode_d16> {
  public:
-  constexpr operator DwVfpRegister() const { return DwVfpRegister(reg_code_); }
+  constexpr operator DwVfpRegister() const { return DwVfpRegister(code()); }
 
   SwVfpRegister low() const { return SwVfpRegister::from_code(code() * 2); }
   SwVfpRegister high() const {

src/codegen/arm64/assembler-arm64-inl.h

@@ -45,12 +45,12 @@ inline bool CPURegister::IsSameSizeAndType(const CPURegister& other) const {
 
 inline bool CPURegister::IsZero() const {
   DCHECK(is_valid());
-  return IsRegister() && (reg_code_ == kZeroRegCode);
+  return IsRegister() && (code() == kZeroRegCode);
 }
 
 inline bool CPURegister::IsSP() const {
   DCHECK(is_valid());
-  return IsRegister() && (reg_code_ == kSPRegInternalCode);
+  return IsRegister() && (code() == kSPRegInternalCode);
 }
 
 inline void CPURegList::Combine(const CPURegList& other) {
@@ -142,52 +142,52 @@ inline VRegister VRegister::VRegFromCode(unsigned code) {
 
 inline Register CPURegister::W() const {
   DCHECK(IsRegister());
-  return Register::WRegFromCode(reg_code_);
+  return Register::WRegFromCode(code());
 }
 
 inline Register CPURegister::Reg() const {
   DCHECK(IsRegister());
-  return Register::Create(reg_code_, reg_size_);
+  return Register::Create(code(), reg_size_);
 }
 
 inline VRegister CPURegister::VReg() const {
   DCHECK(IsVRegister());
-  return VRegister::Create(reg_code_, reg_size_);
+  return VRegister::Create(code(), reg_size_);
 }
 
 inline Register CPURegister::X() const {
   DCHECK(IsRegister());
-  return Register::XRegFromCode(reg_code_);
+  return Register::XRegFromCode(code());
 }
 
 inline VRegister CPURegister::V() const {
   DCHECK(IsVRegister());
-  return VRegister::VRegFromCode(reg_code_);
+  return VRegister::VRegFromCode(code());
 }
 
 inline VRegister CPURegister::B() const {
   DCHECK(IsVRegister());
-  return VRegister::BRegFromCode(reg_code_);
+  return VRegister::BRegFromCode(code());
 }
 
 inline VRegister CPURegister::H() const {
   DCHECK(IsVRegister());
-  return VRegister::HRegFromCode(reg_code_);
+  return VRegister::HRegFromCode(code());
 }
 
 inline VRegister CPURegister::S() const {
   DCHECK(IsVRegister());
-  return VRegister::SRegFromCode(reg_code_);
+  return VRegister::SRegFromCode(code());
 }
 
 inline VRegister CPURegister::D() const {
   DCHECK(IsVRegister());
-  return VRegister::DRegFromCode(reg_code_);
+  return VRegister::DRegFromCode(code());
 }
 
 inline VRegister CPURegister::Q() const {
   DCHECK(IsVRegister());
-  return VRegister::QRegFromCode(reg_code_);
+  return VRegister::QRegFromCode(code());
 }
 
 // Immediate.

src/codegen/arm64/macro-assembler-arm64.cc

@@ -3208,10 +3208,10 @@ void TurboAssembler::Printf(const char* format, CPURegister arg0,
     // If any of the arguments are the current stack pointer, allocate a new
     // register for them, and adjust the value to compensate for pushing the
     // caller-saved registers.
-    bool arg0_sp = sp.Aliases(arg0);
-    bool arg1_sp = sp.Aliases(arg1);
-    bool arg2_sp = sp.Aliases(arg2);
-    bool arg3_sp = sp.Aliases(arg3);
+    bool arg0_sp = arg0.is_valid() && sp.Aliases(arg0);
+    bool arg1_sp = arg1.is_valid() && sp.Aliases(arg1);
+    bool arg2_sp = arg2.is_valid() && sp.Aliases(arg2);
+    bool arg3_sp = arg3.is_valid() && sp.Aliases(arg3);
     if (arg0_sp || arg1_sp || arg2_sp || arg3_sp) {
       // Allocate a register to hold the original stack pointer value, to pass
       // to PrintfNoPreserve as an argument.

src/codegen/arm64/register-arm64.h

@@ -151,7 +151,7 @@ class CPURegister : public RegisterBase<CPURegister, kRegAfterLast> {
   }
   bool IsNone() const { return reg_type_ == kNoRegister; }
   constexpr bool Aliases(const CPURegister& other) const {
-    return (reg_code_ == other.reg_code_) && (reg_type_ == other.reg_type_);
+    return RegisterBase::operator==(other) && reg_type_ == other.reg_type_;
   }
 
   constexpr bool operator==(const CPURegister& other) const {

src/codegen/ia32/register-ia32.h

@@ -59,7 +59,7 @@ enum RegisterCode {
 
 class Register : public RegisterBase<Register, kRegAfterLast> {
  public:
-  bool is_byte_register() const { return reg_code_ <= 3; }
+  bool is_byte_register() const { return code() <= 3; }
 
  private:
   friend class RegisterBase<Register, kRegAfterLast>;

src/codegen/register.h

@@ -69,6 +69,8 @@ class RegisterBase {
 
  protected:
   explicit constexpr RegisterBase(int code) : reg_code_(code) {}
+
+ private:
   int reg_code_;
 };
 

src/codegen/x64/register-x64.h

@@ -52,13 +52,13 @@ enum RegisterCode {
 
 class Register : public RegisterBase<Register, kRegAfterLast> {
  public:
-  bool is_byte_register() const { return reg_code_ <= 3; }
+  bool is_byte_register() const { return code() <= 3; }
   // Return the high bit of the register code as a 0 or 1.  Used often
   // when constructing the REX prefix byte.
-  int high_bit() const { return reg_code_ >> 3; }
+  int high_bit() const { return code() >> 3; }
   // Return the 3 low bits of the register code.  Used when encoding registers
   // in modR/M, SIB, and opcode bytes.
-  int low_bits() const { return reg_code_ & 0x7; }
+  int low_bits() const { return code() & 0x7; }
 
  private:
   friend class RegisterBase<Register, kRegAfterLast>;
@@ -154,10 +154,10 @@ class XMMRegister : public RegisterBase<XMMRegister, kDoubleAfterLast> {
  public:
   // Return the high bit of the register code as a 0 or 1.  Used often
   // when constructing the REX prefix byte.
-  int high_bit() const { return reg_code_ >> 3; }
+  int high_bit() const { return code() >> 3; }
   // Return the 3 low bits of the register code.  Used when encoding registers
   // in modR/M, SIB, and opcode bytes.
-  int low_bits() const { return reg_code_ & 0x7; }
+  int low_bits() const { return code() & 0x7; }
 
  private:
   friend class RegisterBase<XMMRegister, kDoubleAfterLast>;