From c00f7378b78ec5545de0af179d1a84acb26b94ee Mon Sep 17 00:00:00 2001
From: tuz358 <orca00358@gmail.com>
Date: Sun, 18 Mar 2018 15:51:14 +0900
Subject: [PATCH] Add sub_rm32_imm(0x81,0x83) instruction

---
 include/instructions.h |  1 +
 instructions.cpp       | 22 ++++++++++++++++++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/include/instructions.h b/include/instructions.h
index 8e81bff..1fa0e79 100644
--- a/include/instructions.h
+++ b/include/instructions.h
@@ -137,5 +137,6 @@ public:
   void adc_rm32_imm(int imm_flag);
   void sbb_rm32_imm(int imm_flag);
   void and_rm32_imm(int imm_flag);
+  void sub_rm32_imm(int imm_flag);
   void cmp_rm32_imm8();
 };
diff --git a/instructions.cpp b/instructions.cpp
index a5dc016..e969b35 100644
--- a/instructions.cpp
+++ b/instructions.cpp
@@ -487,7 +487,7 @@ void Instructions::opcode_81(){
       and_rm32_imm(IMM32);
       break;
     case 5:
-      // TODO: sub_rm32_imm32();
+      sub_rm32_imm(IMM32);
       break;
     case 6:
       // TODO: xor_rm32_imm32();
@@ -523,7 +523,7 @@ void Instructions::opcode_83(){
       and_rm32_imm(IMM8);
       break;
     case 5:
-      // TODO: sub_rm32_imm8();
+      sub_rm32_imm(IMM8);
       break;
     case 6:
       // TODO: xor_rm32_imm8();
@@ -874,6 +874,24 @@ void Instructions::and_rm32_imm(int imm_flag){
   this->eip++;
 }
 
+void Instructions::sub_rm32_imm(int imm_flag){
+  //printf("sub_rm32_imm called.\n");
+
+  this->eip++;
+
+  if(imm_flag == IMM8){
+    uint8_t imm8 = memory.read_uint8(this->eip);
+    this->registers[this->M] -= imm8;
+  } else if(imm_flag == IMM32){
+    uint32_t imm32 = memory.read_uint32(this->eip);
+    imm32 = swap_endian32(imm32);
+    this->registers[this->M] -= imm32;
+  } else {
+  }
+
+  this->eip++;
+}
+
 void Instructions::cmp_rm32_imm8(){
   //printf("cmp_rm32_imm8 called.\n");