From 8065ada31f6e7d9b7a58d2e2f06fac2fb1be9c82 Mon Sep 17 00:00:00 2001
From: Stanislav Shwartsman <sshwarts@users.sourceforge.net>
Date: Thu, 18 Oct 2007 21:27:56 +0000
Subject: [PATCH] Some EIP setting cleanups. OK, currently I see big mess with
 setting of CS/EIP and SS/ESP everywhere, I have to unify it and make it
 easier !

---
 bochs/cpu/call_far.cc         | 22 +++++++++++++++++++---
 bochs/cpu/ctrl_xfer16.cc      | 22 ++++++++++------------
 bochs/cpu/ctrl_xfer32.cc      | 31 ++++++++++++++++---------------
 bochs/cpu/ctrl_xfer64.cc      |  6 +-----
 bochs/cpu/ctrl_xfer_pro.cc    |  4 ++--
 bochs/cpu/exception.cc        | 10 +++++++++-
 bochs/cpu/segment_ctrl_pro.cc |  6 +++++-
 7 files changed, 62 insertions(+), 39 deletions(-)

diff --git a/bochs/cpu/call_far.cc b/bochs/cpu/call_far.cc
index 826b42c7e..06a8e7898 100755
--- a/bochs/cpu/call_far.cc
+++ b/bochs/cpu/call_far.cc
@@ -1,5 +1,5 @@
 ////////////////////////////////////////////////////////////////////////
-// $Id: call_far.cc,v 1.15 2007-02-03 21:36:40 sshwarts Exp $
+// $Id: call_far.cc,v 1.16 2007-10-18 21:27:56 sshwarts Exp $
 /////////////////////////////////////////////////////////////////////////
 //
 //  Copyright (C) 2001  MandrakeSoft S.A.
@@ -366,7 +366,8 @@ BX_CPU_C::call_protected(bxInstruction_c *i, Bit16u cs_raw, bx_address disp)
             }
           }
 
-          // Help for OS/2
+          // The follwoing push instructions might have a page fault which cannot
+          // be detected at this stage
           BX_CPU_THIS_PTR except_chk = 1;  
           BX_CPU_THIS_PTR except_cs = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS];
           BX_CPU_THIS_PTR except_ss = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS];
@@ -540,12 +541,17 @@ BX_CPU_C::call_gate64(bx_selector_t *gate_selector)
     parse_selector(0, &ss_selector);
     parse_descriptor(0, 0, &ss_descriptor);
 
+    // The following push instructions might have a page fault which cannot
+    // be detected at this stage
+    BX_CPU_THIS_PTR except_chk = 1;  
+    BX_CPU_THIS_PTR except_cs = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS];
+    BX_CPU_THIS_PTR except_ss = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS];
+
     // load CS:RIP (guaranteed to be in 64 bit mode)
     branch_far64(&cs_selector, &cs_descriptor, new_RIP, cs_descriptor.dpl);
 
     // set up null SS descriptor
     load_ss(&ss_selector, &ss_descriptor, cs_descriptor.dpl);
-
     RSP = RSP_for_cpl_x;
 
     // push old stack long pointer onto new stack
@@ -554,6 +560,8 @@ BX_CPU_C::call_gate64(bx_selector_t *gate_selector)
     // push long pointer to return address onto new stack
     push_64(old_CS);
     push_64(old_RIP);
+
+    BX_CPU_THIS_PTR except_chk = 0;
   }
   else
   {
@@ -566,12 +574,20 @@ BX_CPU_C::call_gate64(bx_selector_t *gate_selector)
       exception(BX_GP_EXCEPTION, 0, 0);
     }
 
+    // The following push instructions might have a page fault which cannot
+    // be detected at this stage
+    BX_CPU_THIS_PTR except_chk = 1;  
+    BX_CPU_THIS_PTR except_cs = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS];
+    BX_CPU_THIS_PTR except_ss = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS];
+
     // load CS:RIP (guaranteed to be in 64 bit mode)
     branch_far64(&cs_selector, &cs_descriptor, new_RIP, CPL);
 
     // push return address onto stack
     push_64(old_CS);
     push_64(old_RIP);
+
+    BX_CPU_THIS_PTR except_chk = 0;
   }
 }
 #endif
diff --git a/bochs/cpu/ctrl_xfer16.cc b/bochs/cpu/ctrl_xfer16.cc
index bd4f32a41..af2e29f9b 100644
--- a/bochs/cpu/ctrl_xfer16.cc
+++ b/bochs/cpu/ctrl_xfer16.cc
@@ -1,5 +1,5 @@
 /////////////////////////////////////////////////////////////////////////
-// $Id: ctrl_xfer16.cc,v 1.37 2007-07-09 15:16:11 sshwarts Exp $
+// $Id: ctrl_xfer16.cc,v 1.38 2007-10-18 21:27:56 sshwarts Exp $
 /////////////////////////////////////////////////////////////////////////
 //
 //  Copyright (C) 2001  MandrakeSoft S.A.
@@ -103,8 +103,8 @@ void BX_CPU_C::RETfar16_Iw(bxInstruction_c *i)
   pop_16(&ip);
   pop_16(&cs_raw);
 
-  EIP = (Bit32u) ip;
   load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
+  EIP = (Bit32u) ip;
 
   if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b)
     ESP += imm16;
@@ -135,8 +135,9 @@ void BX_CPU_C::RETfar16(bxInstruction_c *i)
 
   pop_16(&ip);
   pop_16(&cs_raw);
-  EIP = (Bit32u) ip;
+
   load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
+  EIP = (Bit32u) ip;
 
 done:
   BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_RET,
@@ -154,13 +155,11 @@ void BX_CPU_C::CALL_Aw(bxInstruction_c *i)
   new_EIP = EIP + (Bit32s) i->Id();
   new_EIP &= 0x0000ffff;
 
-#if BX_CPU_LEVEL >= 2
   if (new_EIP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled)
   {
     BX_ERROR(("CALL_Aw: new_IP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].limit"));
     exception(BX_GP_EXCEPTION, 0, 0);
   }
-#endif
 
   /* push 16 bit EA of next instruction */
   push_16(IP);
@@ -192,8 +191,9 @@ void BX_CPU_C::CALL16_Ap(bxInstruction_c *i)
 
   push_16(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value);
   push_16((Bit16u) EIP);
-  EIP = (Bit32u) disp16;
+
   load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
+  EIP = (Bit32u) disp16;
 
 done:
   BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_CALL,
@@ -248,7 +248,7 @@ void BX_CPU_C::CALL16_Ep(bxInstruction_c *i)
   read_virtual_word(i->seg(), RMAddr(i), &op1_16);
   read_virtual_word(i->seg(), RMAddr(i)+2, &cs_raw);
 
-  if ( protected_mode() ) {
+  if (protected_mode()) {
     BX_CPU_THIS_PTR call_protected(i, cs_raw, op1_16);
     goto done;
   }
@@ -256,8 +256,8 @@ void BX_CPU_C::CALL16_Ep(bxInstruction_c *i)
   push_16(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value);
   push_16(IP);
 
-  EIP = op1_16;
   load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
+  EIP = op1_16;
 
 done:
   BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_CALL,
@@ -382,8 +382,8 @@ void BX_CPU_C::JMP16_Ep(bxInstruction_c *i)
   }
 #endif
 
-  EIP = op1_16;
   load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
+  EIP = op1_16;
 
 done:
   BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_JMP,
@@ -408,12 +408,10 @@ void BX_CPU_C::IRET16(bxInstruction_c *i)
     goto done;
   }
 
-#if BX_CPU_LEVEL >= 2
-  if (BX_CPU_THIS_PTR cr0.get_PE()) {
+  if (protected_mode()) {
     iret_protected(i);
     goto done;
   }
-#endif
 
   if (! can_pop(6)) {
     BX_ERROR(("IRET: top 6 bytes of stack not within stack limits"));
diff --git a/bochs/cpu/ctrl_xfer32.cc b/bochs/cpu/ctrl_xfer32.cc
index fb7657251..b2318aead 100644
--- a/bochs/cpu/ctrl_xfer32.cc
+++ b/bochs/cpu/ctrl_xfer32.cc
@@ -1,5 +1,5 @@
 /////////////////////////////////////////////////////////////////////////
-// $Id: ctrl_xfer32.cc,v 1.49 2006-06-09 22:29:06 sshwarts Exp $
+// $Id: ctrl_xfer32.cc,v 1.50 2007-10-18 21:27:56 sshwarts Exp $
 /////////////////////////////////////////////////////////////////////////
 //
 //  Copyright (C) 2001  MandrakeSoft S.A.
@@ -85,8 +85,9 @@ void BX_CPU_C::RETfar32_Iw(bxInstruction_c *i)
 
   pop_32(&eip);
   pop_32(&ecs_raw);
-  EIP = eip;
+
   load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], (Bit16u) ecs_raw);
+  EIP = eip;
 
   if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b)
     ESP += imm16;
@@ -115,8 +116,9 @@ void BX_CPU_C::RETfar32(bxInstruction_c *i)
 
   pop_32(&eip);
   pop_32(&ecs_raw); /* 32bit pop, MSW discarded */
-  EIP = eip;
+
   load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], (Bit16u) ecs_raw);
+  EIP = eip;
 
 done:
   BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_RET,
@@ -164,8 +166,9 @@ void BX_CPU_C::CALL32_Ap(bxInstruction_c *i)
 
   push_32(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value);
   push_32(EIP);
-  EIP = disp32;
+
   load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
+  EIP = disp32;
 
 done:
   BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_CALL,
@@ -326,13 +329,12 @@ void BX_CPU_C::JMP_Ap(bxInstruction_c *i)
 
   if (protected_mode()) {
     BX_CPU_THIS_PTR jump_protected(i, cs_raw, disp32);
-    goto done;
+  }
+  else {
+    load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
+    EIP = disp32;
   }
 
-  load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
-  EIP = disp32;
-
-done:
   BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_JMP,
                       BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value, EIP);
 }
@@ -374,15 +376,14 @@ void BX_CPU_C::JMP32_Ep(bxInstruction_c *i)
   read_virtual_dword(i->seg(), RMAddr(i), &op1_32);
   read_virtual_word(i->seg(), RMAddr(i)+4, &cs_raw);
 
-  if ( protected_mode() ) {
+  if (protected_mode()) {
     BX_CPU_THIS_PTR jump_protected(i, cs_raw, op1_32);
-    goto done;
+  }
+  else {
+    load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
+    EIP = op1_32;
   }
 
-  EIP = op1_32;
-  load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
-
-done:
   BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_JMP,
                       BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value, EIP);
 }
diff --git a/bochs/cpu/ctrl_xfer64.cc b/bochs/cpu/ctrl_xfer64.cc
index f157a7a7d..886184846 100644
--- a/bochs/cpu/ctrl_xfer64.cc
+++ b/bochs/cpu/ctrl_xfer64.cc
@@ -1,5 +1,5 @@
 /////////////////////////////////////////////////////////////////////////
-// $Id: ctrl_xfer64.cc,v 1.48 2007-09-25 16:11:32 sshwarts Exp $
+// $Id: ctrl_xfer64.cc,v 1.49 2007-10-18 21:27:56 sshwarts Exp $
 /////////////////////////////////////////////////////////////////////////
 //
 //  Copyright (C) 2001  MandrakeSoft S.A.
@@ -183,8 +183,6 @@ void BX_CPU_C::CALL64_Ep(bxInstruction_c *i)
 
   BX_ASSERT(protected_mode());
 
-  BX_INFO(("CallFar64 instruction executed ..."));
-
   BX_CPU_THIS_PTR call_protected(i, cs_raw, op1_32);
 
   BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_CALL,
@@ -274,8 +272,6 @@ void BX_CPU_C::JMP64_Ep(bxInstruction_c *i)
   read_virtual_dword(i->seg(), RMAddr(i), &op1_32);
   read_virtual_word(i->seg(), RMAddr(i)+4, &cs_raw);
 
-  BX_INFO(("JmpFar64 instruction executed ..."));
-
   BX_ASSERT(protected_mode());
   BX_CPU_THIS_PTR jump_protected(i, cs_raw, op1_32);
 
diff --git a/bochs/cpu/ctrl_xfer_pro.cc b/bochs/cpu/ctrl_xfer_pro.cc
index 0b93a8a1f..172919585 100644
--- a/bochs/cpu/ctrl_xfer_pro.cc
+++ b/bochs/cpu/ctrl_xfer_pro.cc
@@ -1,5 +1,5 @@
 ////////////////////////////////////////////////////////////////////////
-// $Id: ctrl_xfer_pro.cc,v 1.58 2007-09-25 16:11:32 sshwarts Exp $
+// $Id: ctrl_xfer_pro.cc,v 1.59 2007-10-18 21:27:56 sshwarts Exp $
 /////////////////////////////////////////////////////////////////////////
 //
 //  Copyright (C) 2001  MandrakeSoft S.A.
@@ -98,7 +98,7 @@ BX_CPU_C::load_cs(bx_selector_t *selector, bx_descriptor_t *descriptor, Bit8u cp
   /* caller may request different CPL then in selector */
   BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.rpl = cpl;
   BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.valid  = 1;
-  // Added cpl to the selector value.
+  // Add cpl to the selector value.
   BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value =
     (0xfffc & BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value) | cpl;
 
diff --git a/bochs/cpu/exception.cc b/bochs/cpu/exception.cc
index dec592100..f49350d84 100644
--- a/bochs/cpu/exception.cc
+++ b/bochs/cpu/exception.cc
@@ -1,5 +1,5 @@
 /////////////////////////////////////////////////////////////////////////
-// $Id: exception.cc,v 1.90 2007-09-27 16:22:14 sshwarts Exp $
+// $Id: exception.cc,v 1.91 2007-10-18 21:27:56 sshwarts Exp $
 /////////////////////////////////////////////////////////////////////////
 //
 //  Copyright (C) 2001  MandrakeSoft S.A.
@@ -197,6 +197,12 @@ void BX_CPU_C::long_mode_int(Bit8u vector, bx_bool is_INT, bx_bool is_error_code
     parse_selector(0, &ss_selector);
     parse_descriptor(0, 0, &ss_descriptor);
 
+    // The follwoing push instructions might have a page fault which cannot
+    // be detected at this stage
+    BX_CPU_THIS_PTR except_chk = 1;
+    BX_CPU_THIS_PTR except_cs = BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS];
+    BX_CPU_THIS_PTR except_ss = BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS];
+
     // load CS:RIP (guaranteed to be in 64 bit mode)
     branch_far64(&cs_selector, &cs_descriptor, gate_dest_offset, cs_descriptor.dpl);
 
@@ -217,6 +223,8 @@ void BX_CPU_C::long_mode_int(Bit8u vector, bx_bool is_INT, bx_bool is_error_code
     if (is_error_code)
       push_64(error_code);
 
+    BX_CPU_THIS_PTR except_chk = 0;
+
     // if INTERRUPT GATE set IF to 0
     if (!(gate_descriptor.type & 1)) // even is int-gate
       BX_CPU_THIS_PTR clear_IF();
diff --git a/bochs/cpu/segment_ctrl_pro.cc b/bochs/cpu/segment_ctrl_pro.cc
index b3ba085d3..67df4fe0e 100644
--- a/bochs/cpu/segment_ctrl_pro.cc
+++ b/bochs/cpu/segment_ctrl_pro.cc
@@ -1,5 +1,5 @@
 /////////////////////////////////////////////////////////////////////////
-// $Id: segment_ctrl_pro.cc,v 1.71 2007-09-25 16:11:32 sshwarts Exp $
+// $Id: segment_ctrl_pro.cc,v 1.72 2007-10-18 21:27:56 sshwarts Exp $
 /////////////////////////////////////////////////////////////////////////
 //
 //  Copyright (C) 2001  MandrakeSoft S.A.
@@ -643,6 +643,10 @@ BX_CPU_C::load_ss(bx_selector_t *selector, bx_descriptor_t *descriptor, Bit8u cp
   BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache = *descriptor;
   BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.rpl = cpl;
 
+  // Add cpl to the selector value.
+  BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value =
+    (0xfffc & BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value) | cpl;
+
 #if BX_SUPPORT_X86_64
   if (BX_CPU_THIS_PTR cpu_mode == BX_MODE_LONG_64) {
     loadSRegLMNominal(BX_SEG_REG_SS, selector->value, cpl);