improve performance by asserting async_event for debugger instead of …

…checking for bx_dbg.debugger_active every instruction
bochs-emu · Nov 23, 2024 · aa215ce · aa215ce
1 parent dcf961d
commit aa215ce
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Showing 4 changed files with 26 additions and 24 deletions.
diff --git a/bochs/cpu/cpu.cc b/bochs/cpu/cpu.cc
@@ -75,11 +75,15 @@ void BX_CPU_C::cpu_loop_debugger(void)
   BX_CPU_THIS_PTR prev_rip = RIP; // commit new EIP
   BX_CPU_THIS_PTR speculative_rsp = false;
 
+  // stop tracing after every instruction to handle in internal debugger
+  BX_CPU_THIS_PTR async_event |= BX_ASYNC_EVENT_STOP_TRACE;
+
   while (1) {
 
     // check on events which occurred for previous instructions (traps)
     // and ones which are asynchronous to the CPU (hardware interrupts)
-    if (BX_CPU_THIS_PTR async_event) {
+    Bit32u handle_event = BX_CPU_THIS_PTR async_event & ~BX_ASYNC_EVENT_STOP_TRACE;
+    if (handle_event) {
       if (handleAsyncEvent()) {
         // If request to return to caller ASAP.
         return;
@@ -116,10 +120,6 @@ void BX_CPU_C::cpu_loop_debugger(void)
         last = i + (entry->tlen);
       }
     }
-
-    // clear stop trace magic indication that probably was set by repeat or branch32/64
-    BX_CPU_THIS_PTR async_event &= ~BX_ASYNC_EVENT_STOP_TRACE;
-
   }  // while (1)
 }
 #endif // BX_DEBUGGER
@@ -413,6 +413,8 @@ void BX_CPP_AttrRegparmN(2) BX_CPU_C::repeat(bxInstruction_c *i, BxRepIterationP
     return;
   }
 
+  BX_ASSERT(! bx_dbg.debugger_active || BX_CPU_THIS_PTR async_event);
+
   BX_CPU_THIS_PTR clear_RF();
 
 #if BX_SUPPORT_X86_64
@@ -425,7 +427,7 @@ void BX_CPP_AttrRegparmN(2) BX_CPU_C::repeat(bxInstruction_c *i, BxRepIterationP
       }
       if (RCX == 0) return;
 
-      if (BX_CPU_THIS_PTR async_event || bx_dbg.debugger_active)
+      if (BX_CPU_THIS_PTR async_event)
         break; // exit always if debugger enabled
 
       BX_CPU_THIS_PTR icount++;
@@ -444,7 +446,7 @@ void BX_CPP_AttrRegparmN(2) BX_CPU_C::repeat(bxInstruction_c *i, BxRepIterationP
       }
       if (ECX == 0) return;
 
-      if (BX_CPU_THIS_PTR async_event || bx_dbg.debugger_active)
+      if (BX_CPU_THIS_PTR async_event)
         break; // exit always if debugger enabled
 
       BX_CPU_THIS_PTR icount++;
@@ -462,7 +464,7 @@ void BX_CPP_AttrRegparmN(2) BX_CPU_C::repeat(bxInstruction_c *i, BxRepIterationP
       }
       if (CX == 0) return;
 
-      if (BX_CPU_THIS_PTR async_event || bx_dbg.debugger_active)
+      if (BX_CPU_THIS_PTR async_event)
         break; // exit always if debugger enabled
 
       BX_CPU_THIS_PTR icount++;
@@ -502,7 +504,7 @@ void BX_CPP_AttrRegparmN(2) BX_CPU_C::repeat_ZF(bxInstruction_c *i, BxRepIterati
         }
         if (! get_ZF() || RCX == 0) return;
 
-        if (BX_CPU_THIS_PTR async_event || bx_dbg.debugger_active)
+        if (BX_CPU_THIS_PTR async_event)
           break; // exit always if debugger enabled
 
         BX_CPU_THIS_PTR icount++;
@@ -521,7 +523,7 @@ void BX_CPP_AttrRegparmN(2) BX_CPU_C::repeat_ZF(bxInstruction_c *i, BxRepIterati
         }
         if (! get_ZF() || ECX == 0) return;
 
-        if (BX_CPU_THIS_PTR async_event || bx_dbg.debugger_active)
+        if (BX_CPU_THIS_PTR async_event)
           break; // exit always if debugger enabled
 
         BX_CPU_THIS_PTR icount++;
@@ -539,7 +541,7 @@ void BX_CPP_AttrRegparmN(2) BX_CPU_C::repeat_ZF(bxInstruction_c *i, BxRepIterati
         }
         if (! get_ZF() || CX == 0) return;
 
-        if (BX_CPU_THIS_PTR async_event || bx_dbg.debugger_active)
+        if (BX_CPU_THIS_PTR async_event)
           break; // exit always if debugger enabled
 
         BX_CPU_THIS_PTR icount++;
@@ -559,7 +561,7 @@ void BX_CPP_AttrRegparmN(2) BX_CPU_C::repeat_ZF(bxInstruction_c *i, BxRepIterati
         }
         if (get_ZF() || RCX == 0) return;
 
-        if (BX_CPU_THIS_PTR async_event || bx_dbg.debugger_active)
+        if (BX_CPU_THIS_PTR async_event)
           break; // exit always if debugger enabled
 
         BX_CPU_THIS_PTR icount++;
@@ -578,7 +580,7 @@ void BX_CPP_AttrRegparmN(2) BX_CPU_C::repeat_ZF(bxInstruction_c *i, BxRepIterati
         }
         if (get_ZF() || ECX == 0) return;
 
-        if (BX_CPU_THIS_PTR async_event || bx_dbg.debugger_active)
+        if (BX_CPU_THIS_PTR async_event)
           break; // exit always if debugger enabled
 
         BX_CPU_THIS_PTR icount++;
@@ -596,7 +598,7 @@ void BX_CPP_AttrRegparmN(2) BX_CPU_C::repeat_ZF(bxInstruction_c *i, BxRepIterati
         }
         if (get_ZF() || CX == 0) return;
 
-        if (BX_CPU_THIS_PTR async_event || bx_dbg.debugger_active)
+        if (BX_CPU_THIS_PTR async_event)
           break; // exit always if debugger enabled
 
         BX_CPU_THIS_PTR icount++;

diff --git a/bochs/cpu/cpu.h b/bochs/cpu/cpu.h
@@ -5871,7 +5871,7 @@ class bxInstruction_c;
 
 #define BX_NEXT_INSTR(i) {                             \
   BX_COMMIT_INSTRUCTION(i);                            \
-  if (BX_CPU_THIS_PTR async_event || bx_dbg.debugger_active) return;             \
+  if (BX_CPU_THIS_PTR async_event) return;             \
   ++i;                                                 \
   BX_EXECUTE_INSTRUCTION(i);                           \
 }

diff --git a/bochs/cpu/io.cc b/bochs/cpu/io.cc
@@ -332,7 +332,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::INSW32_YwDX(bxInstruction_c *i)
   /* If conditions are right, we can transfer IO to physical memory
    * in a batch, rather than one instruction at a time.
    */
-  if (i->repUsedL() && !BX_CPU_THIS_PTR async_event && !bx_dbg.debugger_active)
+  if (i->repUsedL() && !BX_CPU_THIS_PTR async_event)
   {
     Bit32u wordCount = ECX;
     BX_ASSERT(wordCount > 0);
@@ -583,7 +583,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::OUTSW32_DXXw(bxInstruction_c *i)
   /* If conditions are right, we can transfer IO to physical memory
    * in a batch, rather than one instruction at a time.
    */
-  if (i->repUsedL() && !BX_CPU_THIS_PTR async_event && !bx_dbg.debugger_active) {
+  if (i->repUsedL() && !BX_CPU_THIS_PTR async_event) {
     Bit32u wordCount = ECX;
     wordCount = FastRepOUTSW(i->seg(), esi, DX, wordCount);
     if (wordCount) {

diff --git a/bochs/cpu/string.cc b/bochs/cpu/string.cc
@@ -131,7 +131,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::MOVSB32_YbXb(bxInstruction_c *i)
 #if BX_SUPPORT_REPEAT_SPEEDUPS
   /* If conditions are right, we can transfer IO to physical memory
    * in a batch, rather than one instruction at a time */
-  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event && !bx_dbg.debugger_active)
+  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event)
   {
     Bit32u byteCount = FastRepMOVSB(i->seg(), ESI, BX_SEG_REG_ES, EDI, ECX, 1);
     if (byteCount) {
@@ -174,7 +174,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::MOVSB64_YbXb(bxInstruction_c *i)
 #if BX_SUPPORT_REPEAT_SPEEDUPS
   /* If conditions are right, we can transfer IO to physical memory
    * in a batch, rather than one instruction at a time */
-  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event && !bx_dbg.debugger_active)
+  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event)
   {
     Bit32u byteCount = FastRepMOVSB(get_laddr64(i->seg(), rsi), rdi, ECX, 1);
     if (byteCount) {
@@ -309,7 +309,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::MOVSD32_YdXd(bxInstruction_c *i)
   /* If conditions are right, we can transfer IO to physical memory
    * in a batch, rather than one instruction at a time.
    */
-  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event && !bx_dbg.debugger_active)
+  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event)
   {
     Bit32u byteCount = FastRepMOVSB(i->seg(), esi, BX_SEG_REG_ES, edi, ECX*4, 4);
     if (byteCount) {
@@ -357,7 +357,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::MOVSD64_YdXd(bxInstruction_c *i)
   /* If conditions are right, we can transfer IO to physical memory
    * in a batch, rather than one instruction at a time.
    */
-  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event && !bx_dbg.debugger_active)
+  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event)
   {
     Bit32u byteCount = FastRepMOVSB(get_laddr64(i->seg(), rsi), rdi, ECX*4, 4);
     if (byteCount) {
@@ -425,7 +425,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::MOVSQ64_YqXq(bxInstruction_c *i)
   /* If conditions are right, we can transfer IO to physical memory
    * in a batch, rather than one instruction at a time.
    */
-  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event && !bx_dbg.debugger_active)
+  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event)
   {
     Bit32u byteCount = FastRepMOVSB(get_laddr64(i->seg(), rsi), rdi, ECX*8, 8);
     if (byteCount) {
@@ -1308,7 +1308,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::STOSB32_YbAL(bxInstruction_c *i)
   /* If conditions are right, we can transfer IO to physical memory
    * in a batch, rather than one instruction at a time.
    */
-  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event && !bx_dbg.debugger_active)
+  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event)
   {
     Bit32u byteCount = FastRepSTOSB(BX_SEG_REG_ES, edi, AL, ECX);
     if (byteCount) {
@@ -1349,7 +1349,7 @@ void BX_CPP_AttrRegparmN(1) BX_CPU_C::STOSB64_YbAL(bxInstruction_c *i)
   /* If conditions are right, we can transfer IO to physical memory
    * in a batch, rather than one instruction at a time.
    */
-  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event && !bx_dbg.debugger_active)
+  if (i->repUsedL() && !BX_CPU_THIS_PTR get_DF() && !BX_CPU_THIS_PTR async_event)
   {
     Bit32u byteCount = FastRepSTOSB(rdi, AL, ECX);
     if (byteCount) {