Allow esi to be an allocatable register on IA32.

src/ia32/assembler-ia32.h

Index: src/ia32/assembler-ia32.h
diff --git a/src/ia32/assembler-ia32.h b/src/ia32/assembler-ia32.h
index 20446b0085e4098c5f133b45c1f0ccf72909038b..f7f71baae58ba07d1d35dc956facb15bcd81805c 100644
--- a/src/ia32/assembler-ia32.h
+++ b/src/ia32/assembler-ia32.h
@@ -30,7 +30,7 @@
 
 // The original source code covered by the above license above has been
 // modified significantly by Google Inc.
-// Copyright 2010 the V8 project authors. All rights reserved.
+// Copyright 2011 the V8 project authors. All rights reserved.
 
 // A light-weight IA32 Assembler.
 
@@ -64,30 +64,14 @@ namespace internal {
 // and best performance in optimized code.
 //
 struct Register {
-  static const int kNumAllocatableRegisters = 5;
+  static const int kNumAllocatableRegisters = 6;
   static const int kNumRegisters = 8;
 
-  static int ToAllocationIndex(Register reg) {
-    ASSERT(reg.code() < 4 || reg.code() == 7);
-    return (reg.code() == 7) ? 4 : reg.code();
-  }
+  static inline const char* AllocationIndexToString(int index);
 
-  static Register FromAllocationIndex(int index) {
-    ASSERT(index >= 0 && index < kNumAllocatableRegisters);
-    return (index == 4) ? from_code(7) : from_code(index);
-  }
+  static inline int ToAllocationIndex(Register reg);
 
-  static const char* AllocationIndexToString(int index) {
-    ASSERT(index >= 0 && index < kNumAllocatableRegisters);
-    const char* const names[] = {
-      "eax",
-      "ecx",
-      "edx",
-      "ebx",
-      "edi"
-    };
-    return names[index];
-  }
+  static inline Register FromAllocationIndex(int index);
 
   static Register from_code(int code) {
     Register r = { code };
@@ -110,6 +94,7 @@ struct Register {
   int code_;
 };
 
+
 const Register eax = { 0 };
 const Register ecx = { 1 };
 const Register edx = { 2 };
@@ -121,6 +106,26 @@ const Register edi = { 7 };
 const Register no_reg = { -1 };
 
 
+inline const char* Register::AllocationIndexToString(int index) {
+  ASSERT(index >= 0 && index < kNumAllocatableRegisters);
+  // This is the mapping of allocation indices to registers.
+  const char* const kNames[] = { "eax", "ecx", "edx", "ebx", "esi", "edi" };
+  return kNames[index];
+}
+
+
+inline int Register::ToAllocationIndex(Register reg) {
+  ASSERT(reg.is_valid() && !reg.is(esp) && !reg.is(ebp));
+  return (reg.code() >= 6) ? reg.code() - 2 : reg.code();
+}
+
+
+inline Register Register::FromAllocationIndex(int index)  {
+  ASSERT(index >= 0 && index < kNumAllocatableRegisters);
+  return (index >= 4) ? from_code(index + 2) : from_code(index);
+}
+
+
 struct XMMRegister {
   static const int kNumAllocatableRegisters = 7;
   static const int kNumRegisters = 8;