Convert diamond shaped control flow into a single conditional instruction.

runtime/vm/disassembler_ia32.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/disassembler.h"
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_IA32.
 #if defined(TARGET_ARCH_IA32)
 #include "platform/utils.h"
 #include "vm/allocation.h"
@@ skipping 368 matching lines @@
   }
   buffer_[buffer_pos_] = '\0';
 }
 
 
 static const int kMaxCPURegisters = 8;
 static const char* cpu_regs[kMaxCPURegisters] = {
   "eax", "ecx", "edx", "ebx", "esp", "ebp", "esi", "edi"
 };
 
+static const int kMaxByteCPURegisters = 8;
+static const char* byte_cpu_regs[kMaxByteCPURegisters] = {
+  "al", "cl", "dl", "bl", "ah", "ch", "dh", "bh"
+};
+
 static const int kMaxXmmRegisters = 8;
 static const char* xmm_regs[kMaxXmmRegisters] = {
   "xmm0", "xmm1", "xmm2", "xmm3", "xmm4", "xmm5", "xmm6", "xmm7"
 };
 
-
 void X86Decoder::PrintCPURegister(int reg) {
   ASSERT(0 <= reg);
   ASSERT(reg < kMaxCPURegisters);
   Print(cpu_regs[reg]);
 }
 
 
 void X86Decoder::PrintCPUByteRegister(int reg) {
-  UNIMPLEMENTED();
+  ASSERT(0 <= reg);
+  ASSERT(reg < kMaxByteCPURegisters);
+  Print(byte_cpu_regs[reg]);
 }
 
 
 void X86Decoder::PrintXmmRegister(int reg) {
   ASSERT(0 <= reg);
   ASSERT(reg < kMaxXmmRegisters);
   Print(xmm_regs[reg]);
 }
 
 void X86Decoder::PrintXmmComparison(int comparison) {
@@ skipping 213 matching lines @@
   return PrintRightOperandHelper(modrmp, &X86Decoder::PrintCPURegister);
 }
 
 
 int X86Decoder::PrintRightXmmOperand(uint8_t* modrmp) {
   return PrintRightOperandHelper(modrmp, &X86Decoder::PrintXmmRegister);
 }
 
 
 int X86Decoder::PrintRightByteOperand(uint8_t* modrmp) {
-  UNIMPLEMENTED();
-  return 0;
+  return PrintRightOperandHelper(modrmp, &X86Decoder::PrintCPUByteRegister);
 }
 
 
 int X86Decoder::PrintOperands(const char* mnem,
                               OperandOrder op_order,
                               uint8_t* data) {
   uint8_t modrm = *data;
   int mod, regop, rm;
   GetModRm(modrm, &mod, &regop, &rm);
   int advance = 0;
@@ skipping 1148 matching lines @@
                                   pc);
     pc += instruction_length;
   }
 
   return;
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32