Re-reland: Remove register index/code indirection

src/ia32/lithium-gap-resolver-ia32.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_IA32
 
 #include "src/ia32/lithium-codegen-ia32.h"
 #include "src/ia32/lithium-gap-resolver-ia32.h"
+#include "src/register-configuration.h"
 
 namespace v8 {
 namespace internal {
 
 LGapResolver::LGapResolver(LCodeGen* owner)
     : cgen_(owner),
       moves_(32, owner->zone()),
       source_uses_(),
       destination_uses_(),
       spilled_register_(-1) {}
@@ skipping 139 matching lines @@
   for (int i = 0; i < moves_.length(); ++i) {
     if (!moves_[i].IsEliminated() && moves_[i].source()->Equals(operand)) {
       ++count;
     }
   }
   return count;
 }
 
 
 Register LGapResolver::GetFreeRegisterNot(Register reg) {
-  int skip_index = reg.is(no_reg) ? -1 : Register::ToAllocationIndex(reg);
-  for (int i = 0; i < Register::NumAllocatableRegisters(); ++i) {
-    if (source_uses_[i] == 0 && destination_uses_[i] > 0 && i != skip_index) {
-      return Register::FromAllocationIndex(i);
+  int skip_index = reg.is(no_reg) ? -1 : reg.code();
+  const RegisterConfiguration* config = RegisterConfiguration::ArchDefault();
+  for (int i = 0; i < config->num_allocatable_general_registers(); ++i) {
+    int code = config->GetAllocatableGeneralCode(i);
+    if (source_uses_[code] == 0 && destination_uses_[code] > 0 &&
+        code != skip_index) {
+      return Register::from_code(code);
     }
   }
   return no_reg;
 }
 
 
 bool LGapResolver::HasBeenReset() {
   if (!moves_.is_empty()) return false;
   if (spilled_register_ >= 0) return false;
-
-  for (int i = 0; i < Register::NumAllocatableRegisters(); ++i) {
-    if (source_uses_[i] != 0) return false;
-    if (destination_uses_[i] != 0) return false;
+  const RegisterConfiguration* config = RegisterConfiguration::ArchDefault();
+  for (int i = 0; i < config->num_allocatable_general_registers(); ++i) {
+    int code = config->GetAllocatableGeneralCode(i);
+    if (source_uses_[code] != 0) return false;
+    if (destination_uses_[code] != 0) return false;
   }
   return true;
 }
 
 
 void LGapResolver::Verify() {
 #ifdef ENABLE_SLOW_DCHECKS
   // No operand should be the destination for more than one move.
   for (int i = 0; i < moves_.length(); ++i) {
     LOperand* destination = moves_[i].destination();
     for (int j = i + 1; j < moves_.length(); ++j) {
       SLOW_DCHECK(!destination->Equals(moves_[j].destination()));
     }
   }
 #endif
 }
 
 
 #define __ ACCESS_MASM(cgen_->masm())
 
 void LGapResolver::Finish() {
   if (spilled_register_ >= 0) {
-    __ pop(Register::FromAllocationIndex(spilled_register_));
+    __ pop(Register::from_code(spilled_register_));
     spilled_register_ = -1;
   }
   moves_.Rewind(0);
 }
 
 
 void LGapResolver::EnsureRestored(LOperand* operand) {
   if (operand->IsRegister() && operand->index() == spilled_register_) {
-    __ pop(Register::FromAllocationIndex(spilled_register_));
+    __ pop(Register::from_code(spilled_register_));
     spilled_register_ = -1;
   }
 }
 
 
 Register LGapResolver::EnsureTempRegister() {
   // 1. We may have already spilled to create a temp register.
   if (spilled_register_ >= 0) {
-    return Register::FromAllocationIndex(spilled_register_);
+    return Register::from_code(spilled_register_);
   }
 
   // 2. We may have a free register that we can use without spilling.
   Register free = GetFreeRegisterNot(no_reg);
   if (!free.is(no_reg)) return free;
 
   // 3. Prefer to spill a register that is not used in any remaining move
   // because it will not need to be restored until the end.
-  for (int i = 0; i < Register::NumAllocatableRegisters(); ++i) {
-    if (source_uses_[i] == 0 && destination_uses_[i] == 0) {
-      Register scratch = Register::FromAllocationIndex(i);
+  const RegisterConfiguration* config = RegisterConfiguration::ArchDefault();
+  for (int i = 0; i < config->num_allocatable_general_registers(); ++i) {
+    int code = config->GetAllocatableGeneralCode(i);
+    if (source_uses_[code] == 0 && destination_uses_[code] == 0) {
+      Register scratch = Register::from_code(code);
       __ push(scratch);
-      spilled_register_ = i;
+      spilled_register_ = code;
       return scratch;
     }
   }
 
   // 4. Use an arbitrary register.  Register 0 is as arbitrary as any other.
-  Register scratch = Register::FromAllocationIndex(0);
+  spilled_register_ = config->GetAllocatableGeneralCode(0);
+  Register scratch = Register::from_code(spilled_register_);
   __ push(scratch);
-  spilled_register_ = 0;
   return scratch;
 }
 
 
 void LGapResolver::EmitMove(int index) {
   LOperand* source = moves_[index].source();
   LOperand* destination = moves_[index].destination();
   EnsureRestored(source);
   EnsureRestored(destination);
 
@@ skipping 215 matching lines @@
     source_uses_[destination->index()] = CountSourceUses(destination);
   }
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_IA32