From fa930961c21826d5cc5434886e762875110fa780 Mon Sep 17 00:00:00 2001
From: Stanislav Shwartsman <sshwarts@users.sourceforge.net>
Date: Tue, 23 Aug 2011 21:25:34 +0000
Subject: [PATCH] small optimization

---
 bochs/cpu/crregs.cc       | 36 ++++++++++++++++++++++++------------
 bochs/cpu/msr.cc          |  6 ++++--
 bochs/cpu/paging.cc       |  3 ++-
 bochs/cpu/proc_ctrl.cc    | 15 ++++++++++-----
 bochs/cpu/protect_ctrl.cc |  6 ++++--
 bochs/cpu/xsave.cc        |  3 ++-
 6 files changed, 46 insertions(+), 23 deletions(-)

diff --git a/bochs/cpu/crregs.cc b/bochs/cpu/crregs.cc
index 40b093eb7..c39ec9fe4 100644
--- a/bochs/cpu/crregs.cc
+++ b/bochs/cpu/crregs.cc
@@ -50,7 +50,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_DdRd(bxInstruction_c *i)
     exception(BX_DB_EXCEPTION, 0);
   }
 
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("MOV_DdRd: CPL!=0 not in real mode"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -154,7 +155,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_RdDd(bxInstruction_c *i)
     exception(BX_DB_EXCEPTION, 0);
   }
 
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("MOV_RdDd: CPL!=0 not in real mode"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -378,7 +380,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_RqDq(bxInstruction_c *i)
 
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_CR0Rd(bxInstruction_c *i)
 {
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("MOV_CR0Rd: CPL!=0 not in real mode"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -400,7 +403,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_CR0Rd(bxInstruction_c *i)
 
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_CR2Rd(bxInstruction_c *i)
 {
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("MOV_CR2Rd: CPL!=0 not in real mode"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -412,7 +416,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_CR2Rd(bxInstruction_c *i)
 
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_CR3Rd(bxInstruction_c *i)
 {
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("MOV_CR3Rd: CPL!=0 not in real mode"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -446,7 +451,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_CR3Rd(bxInstruction_c *i)
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_CR4Rd(bxInstruction_c *i)
 {
 #if BX_CPU_LEVEL >= 5
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("MOV_CR4Rd: CPL!=0 not in real mode"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -469,7 +475,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_CR4Rd(bxInstruction_c *i)
 
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_RdCR0(bxInstruction_c *i)
 {
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("MOV_RdCR0: CPL!=0 not in real mode"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -483,7 +490,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_RdCR0(bxInstruction_c *i)
 
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_RdCR2(bxInstruction_c *i)
 {
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("MOV_RdCd: CPL!=0 not in real mode"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -495,7 +503,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_RdCR2(bxInstruction_c *i)
 
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_RdCR3(bxInstruction_c *i)
 {
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("MOV_RdCd: CPL!=0 not in real mode"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -515,7 +524,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_RdCR3(bxInstruction_c *i)
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MOV_RdCR4(bxInstruction_c *i)
 {
 #if BX_CPU_LEVEL >= 5
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("MOV_RdCd: CPL!=0 not in real mode"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -765,7 +775,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::LMSW_Ew(bxInstruction_c *i)
 {
   Bit16u msw;
 
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("LMSW: CPL!=0 not in real mode"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -1219,7 +1230,8 @@ bx_bool BX_CPP_AttrRegparmN(1) BX_CPU_C::SetEFER(bx_address val_64)
 
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::CLTS(bxInstruction_c *i)
 {
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("CLTS: priveledge check failed, generate #GP(0)"));
     exception(BX_GP_EXCEPTION, 0);
   }
diff --git a/bochs/cpu/msr.cc b/bochs/cpu/msr.cc
index 1b5538f6c..d9f3f0fe2 100644
--- a/bochs/cpu/msr.cc
+++ b/bochs/cpu/msr.cc
@@ -288,7 +288,8 @@ bx_bool BX_CPP_AttrRegparmN(2) BX_CPU_C::rdmsr(Bit32u index, Bit64u *msr)
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::RDMSR(bxInstruction_c *i)
 {
 #if BX_CPU_LEVEL >= 5
-  if (!real_mode() && CPL != 0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("RDMSR: CPL != 0 not in real mode"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -739,7 +740,8 @@ bx_bool BX_CPU_C::relocate_apic(Bit64u val_64)
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::WRMSR(bxInstruction_c *i)
 {
 #if BX_CPU_LEVEL >= 5
-  if (!real_mode() && CPL != 0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("WRMSR: CPL != 0 not in real mode"));
     exception(BX_GP_EXCEPTION, 0);
   }
diff --git a/bochs/cpu/paging.cc b/bochs/cpu/paging.cc
index a0dfc0d85..fc1fdcc7f 100644
--- a/bochs/cpu/paging.cc
+++ b/bochs/cpu/paging.cc
@@ -464,7 +464,8 @@ void BX_CPU_C::TLB_invlpg(bx_address laddr)
 
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::INVLPG(bxInstruction_c* i)
 {
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("INVLPG: priveledge check failed, generate #GP(0)"));
     exception(BX_GP_EXCEPTION, 0);
   }
diff --git a/bochs/cpu/proc_ctrl.cc b/bochs/cpu/proc_ctrl.cc
index f5e8bf9ab..8e8654c1e 100644
--- a/bochs/cpu/proc_ctrl.cc
+++ b/bochs/cpu/proc_ctrl.cc
@@ -119,7 +119,8 @@ void BX_CPU_C::shutdown(void)
 
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::HLT(bxInstruction_c *i)
 {
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_DEBUG(("HLT: %s priveledge check failed, CPL=%d, generate #GP(0)",
         cpu_mode_string(BX_CPU_THIS_PTR cpu_mode), CPL));
     exception(BX_GP_EXCEPTION, 0);
@@ -163,7 +164,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::HLT(bxInstruction_c *i)
 /* 0F 08 */
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::INVD(bxInstruction_c *i)
 {
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("INVD: priveledge check failed, generate #GP(0)"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -188,7 +190,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::INVD(bxInstruction_c *i)
 /* 0F 09 */
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::WBINVD(bxInstruction_c *i)
 {
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("INVD/WBINVD: priveledge check failed, generate #GP(0)"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -553,7 +556,8 @@ void BX_CPU_C::check_monitor(bx_phy_address begin_addr, unsigned len)
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MONITOR(bxInstruction_c *i)
 {
 #if BX_SUPPORT_MONITOR_MWAIT
-  if (!real_mode() && CPL != 0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL != 0) {
     BX_DEBUG(("MWAIT instruction not recognized when CPL != 0"));
     exception(BX_UD_EXCEPTION, 0);
   }
@@ -618,7 +622,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MONITOR(bxInstruction_c *i)
 BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::MWAIT(bxInstruction_c *i)
 {
 #if BX_SUPPORT_MONITOR_MWAIT
-  if (!real_mode() && CPL != 0) {
+  // CPL is always 0 in real mode
+  if (/* !real_mode() && */ CPL != 0) {
     BX_DEBUG(("MWAIT instruction not recognized when CPL != 0"));
     exception(BX_UD_EXCEPTION, 0);
   }
diff --git a/bochs/cpu/protect_ctrl.cc b/bochs/cpu/protect_ctrl.cc
index 0557eaead..c6467c908 100644
--- a/bochs/cpu/protect_ctrl.cc
+++ b/bochs/cpu/protect_ctrl.cc
@@ -764,7 +764,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::LGDT_Ms(bxInstruction_c *i)
 {
   BX_ASSERT(BX_CPU_THIS_PTR cpu_mode != BX_MODE_LONG_64);
 
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 is real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("LGDT: CPL != 0 causes #GP"));
     exception(BX_GP_EXCEPTION, 0);
   }
@@ -792,7 +793,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::LIDT_Ms(bxInstruction_c *i)
 {
   BX_ASSERT(BX_CPU_THIS_PTR cpu_mode != BX_MODE_LONG_64);
 
-  if (!real_mode() && CPL!=0) {
+  // CPL is always 0 is real mode
+  if (/* !real_mode() && */ CPL!=0) {
     BX_ERROR(("LIDT: CPL != 0 causes #GP"));
     exception(BX_GP_EXCEPTION, 0);
   }
diff --git a/bochs/cpu/xsave.cc b/bochs/cpu/xsave.cc
index 547bafa01..4daaccca4 100644
--- a/bochs/cpu/xsave.cc
+++ b/bochs/cpu/xsave.cc
@@ -394,7 +394,8 @@ BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::XSETBV(bxInstruction_c *i)
   }
 #endif
 
-  if (v8086_mode() || CPL != 0) {
+  // CPL is always 3 in vm8086 mode
+  if (/* v8086_mode() || */ CPL != 0) {
     BX_ERROR(("XSETBV: The current priveledge level is not 0"));
     exception(BX_GP_EXCEPTION, 0);
   }