From 5e572e462215ae46a0a1d547c2c36830acac8518 Mon Sep 17 00:00:00 2001
From: "kaznacheev@chromium.org"
 <kaznacheev@chromium.org@ce2b1a6d-e550-0410-aec6-3dcde31c8c00>
Date: Thu, 23 Sep 2010 19:01:56 +0000
Subject: [PATCH] Support dec_b instruction in ia32 and x64 disassembler.

Review URL: http://codereview.chromium.org/3412028

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5515 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
---
 src/ia32/disasm-ia32.cc         | 6 +++---
 src/x64/disasm-x64.cc           | 6 +++---
 test/cctest/test-disasm-ia32.cc | 2 ++
 3 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/ia32/disasm-ia32.cc b/src/ia32/disasm-ia32.cc
index 207648b..d499ab2 100644
--- a/src/ia32/disasm-ia32.cc
+++ b/src/ia32/disasm-ia32.cc
@@ -1194,12 +1194,12 @@ int DisassemblerIA32::InstructionDecode(v8::internal::Vector<char> out_buffer,
         { data++;
           int mod, regop, rm;
           get_modrm(*data, &mod, &regop, &rm);
-          if (mod == 3 && regop == ecx) {
-            AppendToBuffer("dec_b %s", NameOfCPURegister(rm));
+          if (regop == ecx) {
+            AppendToBuffer("dec_b ");
+            data += PrintRightOperand(data);
           } else {
             UnimplementedInstruction();
           }
-          data++;
         }
         break;
 
diff --git a/src/x64/disasm-x64.cc b/src/x64/disasm-x64.cc
index 7c9dfc1..26fe39e 100644
--- a/src/x64/disasm-x64.cc
+++ b/src/x64/disasm-x64.cc
@@ -1450,12 +1450,12 @@ int DisassemblerX64::InstructionDecode(v8::internal::Vector<char> out_buffer,
         data++;
         int mod, regop, rm;
         get_modrm(*data, &mod, &regop, &rm);
-        if (mod == 3 && regop == 1) {
-          AppendToBuffer("decb %s", NameOfCPURegister(rm));
+        if (regop == 1) {
+          AppendToBuffer("decb ");
+          data += PrintRightOperand(data);
         } else {
           UnimplementedInstruction();
         }
-        data++;
       }
         break;
 
diff --git a/test/cctest/test-disasm-ia32.cc b/test/cctest/test-disasm-ia32.cc
index 71735bc..18bc435 100644
--- a/test/cctest/test-disasm-ia32.cc
+++ b/test/cctest/test-disasm-ia32.cc
@@ -165,6 +165,8 @@ TEST(DisasmIa320) {
   __ mov(Operand(ebx, ecx, times_4, 10000), edx);
   __ nop();
   __ dec_b(edx);
+  __ dec_b(Operand(eax, 10));
+  __ dec_b(Operand(ebx, ecx, times_4, 10000));
   __ dec(edx);
   __ cdq();
 
-- 
2.7.4