From 4eae91f1ca4e86dd8bb3e70267f768c0bbb3089a Mon Sep 17 00:00:00 2001
From: Shwartsman <stanislav.shwartsman@intel.com>
Date: Sat, 20 Jan 2024 08:19:43 +0200
Subject: [PATCH] addressing issue Possible Undefined Behavior in NEG_EdR() and
 NEG_EdM() #227

---
 bochs/cpu/arith16.cc | 4 ++--
 bochs/cpu/arith32.cc | 4 ++--
 bochs/cpu/arith64.cc | 4 ++--
 bochs/cpu/arith8.cc  | 4 ++--
 4 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/bochs/cpu/arith16.cc b/bochs/cpu/arith16.cc
index 0049b5175..95598ca92 100644
--- a/bochs/cpu/arith16.cc
+++ b/bochs/cpu/arith16.cc
@@ -458,7 +458,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EwM(bxInstruction_c *i)
   bx_address eaddr = BX_CPU_RESOLVE_ADDR(i);
 
   Bit32u op1_16 = read_RMW_virtual_word(i->seg(), eaddr);
-  op1_16 = 0 - (Bit32s)(Bit16s)(op1_16);
+  op1_16 = -op1_16;
   write_RMW_linear_word(op1_16);
 
   SET_FLAGS_OSZAPC_SUB_16(0, 0 - op1_16, op1_16);
@@ -469,7 +469,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EwM(bxInstruction_c *i)
 void BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EwR(bxInstruction_c *i)
 {
   Bit32u op1_16 = BX_READ_16BIT_REG(i->dst());
-  op1_16 = 0 - (Bit32s)(Bit16s)(op1_16);
+  op1_16 = -op1_16;
   BX_WRITE_16BIT_REG(i->dst(), op1_16);
 
   SET_FLAGS_OSZAPC_SUB_16(0, 0 - op1_16, op1_16);
diff --git a/bochs/cpu/arith32.cc b/bochs/cpu/arith32.cc
index 2a3f85943..371dc8c29 100644
--- a/bochs/cpu/arith32.cc
+++ b/bochs/cpu/arith32.cc
@@ -492,7 +492,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EdM(bxInstruction_c *i)
   bx_address eaddr = BX_CPU_RESOLVE_ADDR(i);
 
   Bit32u op1_32 = read_RMW_virtual_dword(i->seg(), eaddr);
-  op1_32 = - (Bit32s)(op1_32);
+  op1_32 = -op1_32;
   write_RMW_linear_dword(op1_32);
 
   SET_FLAGS_OSZAPC_SUB_32(0, 0 - op1_32, op1_32);
@@ -503,7 +503,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EdM(bxInstruction_c *i)
 void BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EdR(bxInstruction_c *i)
 {
   Bit32u op1_32 = BX_READ_32BIT_REG(i->dst());
-  op1_32 = - (Bit32s)(op1_32);
+  op1_32 = -op1_32;
   BX_WRITE_32BIT_REGZ(i->dst(), op1_32);
 
   SET_FLAGS_OSZAPC_SUB_32(0, 0 - op1_32, op1_32);
diff --git a/bochs/cpu/arith64.cc b/bochs/cpu/arith64.cc
index 64999a962..5219fdb03 100644
--- a/bochs/cpu/arith64.cc
+++ b/bochs/cpu/arith64.cc
@@ -492,7 +492,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EqM(bxInstruction_c *i)
   bx_address eaddr = BX_CPU_RESOLVE_ADDR_64(i);
 
   Bit64u op1_64 = read_RMW_linear_qword(i->seg(), get_laddr64(i->seg(), eaddr));
-  op1_64 = - (Bit64s)(op1_64);
+  op1_64 = -op1_64;
   write_RMW_linear_qword(op1_64);
 
   SET_FLAGS_OSZAPC_SUB_64(0, -op1_64, op1_64);
@@ -503,7 +503,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EqM(bxInstruction_c *i)
 void BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EqR(bxInstruction_c *i)
 {
   Bit64u op1_64 = BX_READ_64BIT_REG(i->dst());
-  op1_64 = - (Bit64s)(op1_64);
+  op1_64 = -op1_64;
   BX_WRITE_64BIT_REG(i->dst(), op1_64);
 
   SET_FLAGS_OSZAPC_SUB_64(0, -op1_64, op1_64);
diff --git a/bochs/cpu/arith8.cc b/bochs/cpu/arith8.cc
index 1b4c7dff2..6d527f751 100644
--- a/bochs/cpu/arith8.cc
+++ b/bochs/cpu/arith8.cc
@@ -420,7 +420,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EbM(bxInstruction_c *i)
   bx_address eaddr = BX_CPU_RESOLVE_ADDR(i);
 
   Bit32u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr);
-  op1_8 = - (Bit8s)(op1_8);
+  op1_8 = -op1_8;
   write_RMW_linear_byte(op1_8);
 
   SET_FLAGS_OSZAPC_SUB_8(0, 0 - op1_8, op1_8);
@@ -431,7 +431,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EbM(bxInstruction_c *i)
 void BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EbR(bxInstruction_c *i)
 {
   Bit32u op1_8 = BX_READ_8BIT_REGx(i->dst(), i->extend8bitL());
-  op1_8 = - (Bit8s)(op1_8);
+  op1_8 = -op1_8;
   BX_WRITE_8BIT_REGx(i->dst(), i->extend8bitL(), op1_8);
 
   SET_FLAGS_OSZAPC_SUB_8(0, 0 - op1_8, op1_8);