GDB Stub: More progress

CMakeLists.txt

@@ -121,7 +121,7 @@ option(DINPUT       "DirectInput"
 option(CPPTHREADS   "C++11 threads"                                                 ON)
 option(NEW_DYNAREC  "Use the PCem v15 (\"new\") dynamic recompiler"                 OFF)
 option(MINITRACE    "Enable Chrome tracing using the modified minitrace library"    OFF)
-option(GDBSTUB      "Enable GDB stub server for debugging"                          ON)
+option(GDBSTUB      "Enable GDB stub server for debugging"                          OFF)
 option(DEV_BRANCH   "Development branch"                                            OFF)
 if(NOT WIN32)
 option(QT           "QT GUI"                                                        ON)

src/86box.c

@@ -1204,6 +1204,9 @@ pc_run(void)
 	/* Run a block of code. */
 	startblit();
 	cpu_exec(cpu_s->rspeed / 100);
+#ifdef USE_GDBSTUB /* avoid a KBC FIFO overflow when CPU emulation is stalled */
+	if (gdbstub_step == GDBSTUB_EXEC)
+#endif
 	mouse_process();
 	joystick_process();
 	endblit();

src/cpu/386.c

@@ -259,7 +259,7 @@ exec386(int cycs)
 			timer_process_inline();
 
 #ifdef USE_GDBSTUB
-		if (gdbstub_singlestep)
+		if (gdbstub_instruction())
 			return;
 #endif
 	}

src/cpu/386_dynarec.c

@@ -26,6 +26,7 @@
 #include <86box/fdd.h>
 #include <86box/fdc.h>
 #include <86box/machine.h>
+#include <86box/gdbstub.h>
 #ifdef USE_DYNAREC
 #include "codegen.h"
 #ifdef USE_NEW_DYNAREC
@@ -858,6 +859,11 @@ exec386_dynarec(int cycs)
 			if (TIMER_VAL_LESS_THAN_VAL(timer_target, (uint32_t) tsc))
 				timer_process_inline();
 		}
+
+#ifdef USE_GDBSTUB
+		if (gdbstub_instruction())
+			return;
+#endif
 	}
 
 	cycles_main -= (cycles_start - cycles);

src/cpu/386_dynarec_ops.c

@@ -19,6 +19,7 @@
 #include <86box/mem.h>
 #include <86box/nmi.h>
 #include <86box/pic.h>
+#include <86box/gdbstub.h>
 #include "codegen.h"
 
 #define CPU_BLOCK_END() cpu_block_end = 1

src/cpu/808x.c

@@ -2835,7 +2835,7 @@ execx86(int cycs)
 	}
 
 #ifdef USE_GDBSTUB
-		if (gdbstub_singlestep)
+	if (gdbstub_instruction())
 		return;
 #endif
     }

src/cpu/cpu.c

@@ -36,6 +36,7 @@
 #include <86box/nmi.h>
 #include <86box/pic.h>
 #include <86box/pci.h>
+#include <86box/gdbstub.h>
 #ifdef USE_DYNAREC
 # include "codegen.h"
 #endif
@@ -1383,6 +1384,7 @@ cpu_set(void)
 	cpu_exec = exec386;
     else
 	cpu_exec = execx86;
+    gdbstub_cpu_init();
 }
 
 

src/cpu/x86_ops_int.h

@@ -1,6 +1,10 @@
 static int opINT3(uint32_t fetchdat)
 {
         int cycles_old = cycles; UN_USED(cycles_old);
+#ifdef USE_GDBSTUB
+        if (gdbstub_int3())
+                return 1;
+#endif
         if ((cr0 & 1) && (cpu_state.eflags & VM_FLAG) && (IOPL != 3))
         {
                 x86gpf(NULL,0);

src/cpu/x87_ops.h

@@ -239,86 +239,22 @@ static __inline int64_t x87_fround(double b)
 
         return 0LL;
 }
-#define BIAS80 16383
+
-#define BIAS64 1023
+#include "x87_ops_conv.h"
 
 static __inline double x87_ld80()
 {
-       	int64_t exp64;
+        x87_conv_t test;
-       	int64_t blah;
-       	int64_t exp64final;
-      	int64_t mant64;
-       	int64_t sign;
-	struct {
-		int16_t begin;
-		union
-		{
-                        double d;
-                        uint64_t ll;
-                } eind;
-	} test;
         test.eind.ll = readmeml(easeg,cpu_state.eaaddr);
         test.eind.ll |= (uint64_t)readmeml(easeg,cpu_state.eaaddr+4)<<32;
         test.begin = readmemw(easeg,cpu_state.eaaddr+8);
-
+        return x87_from80(&test);
-       	exp64 = (((test.begin&0x7fff) - BIAS80));
-       	blah = ((exp64 >0)?exp64:-exp64)&0x3ff;
-       	exp64final = ((exp64 >0)?blah:-blah) +BIAS64;
-
-       	mant64 = (test.eind.ll >> 11) & (0xfffffffffffffll);
-       	sign = (test.begin&0x8000)?1:0;
-
-        if ((test.begin & 0x7fff) == 0x7fff)
-                exp64final = 0x7ff;
-        if ((test.begin & 0x7fff) == 0)
-                exp64final = 0;
-        if (test.eind.ll & 0x400)
-                mant64++;
-
-        test.eind.ll = (sign <<63)|(exp64final << 52)| mant64;
-
-	return test.eind.d;
 }
 
 static __inline void x87_st80(double d)
 {
-       	int64_t sign80;
+        x87_conv_t test;
-       	int64_t exp80;
+        x87_to80(d, &test);
-       	int64_t exp80final;
-       	int64_t mant80;
-       	int64_t mant80final;
-
-	struct {
-		int16_t begin;
-		union
-		{
-                        double d;
-                        uint64_t ll;
-                } eind;
-	} test;
-
-	test.eind.d=d;
-
-       	sign80 = (test.eind.ll&(0x8000000000000000ll))?1:0;
-       	exp80 =  test.eind.ll&(0x7ff0000000000000ll);
-       	exp80final = (exp80>>52);
-       	mant80 = test.eind.ll&(0x000fffffffffffffll);
-       	mant80final = (mant80 << 11);
-
-       	if (exp80final == 0x7ff) /*Infinity / Nan*/
-       	{
-                exp80final = 0x7fff;
-                mant80final |= (0x8000000000000000ll);
-        }
-       	else if (d != 0){  /* Zero is a special case */
-       		/* Elvira wants the 8 and tcalc doesn't */
-       		mant80final |= (0x8000000000000000ll);
-       		/* Ca-cyber doesn't like this when result is zero. */
-       		exp80final += (BIAS80 - BIAS64);
-       	}
-       	test.begin = (((int16_t)sign80)<<15)| (int16_t)exp80final;
-       	test.eind.ll = mant80final;
-
         writememl(easeg,cpu_state.eaaddr,test.eind.ll & 0xffffffff);
         writememl(easeg,cpu_state.eaaddr+4,test.eind.ll>>32);
         writememw(easeg,cpu_state.eaaddr+8,test.begin);

src/cpu/x87_ops_conv.h

@@ -0,0 +1,68 @@
+#define BIAS80 16383
+#define BIAS64 1023
+
+typedef struct {
+    int16_t begin;
+    union {
+        double d;
+        uint64_t ll;
+    } eind;
+} x87_conv_t;
+
+static __inline double x87_from80(x87_conv_t *test)
+{
+        int64_t exp64;
+        int64_t blah;
+        int64_t exp64final;
+        int64_t mant64;
+        int64_t sign;
+
+        exp64 = (((test->begin&0x7fff) - BIAS80));
+        blah = ((exp64 >0)?exp64:-exp64)&0x3ff;
+        exp64final = ((exp64 >0)?blah:-blah) +BIAS64;
+
+        mant64 = (test->eind.ll >> 11) & (0xfffffffffffffll);
+        sign = (test->begin&0x8000)?1:0;
+
+        if ((test->begin & 0x7fff) == 0x7fff)
+                exp64final = 0x7ff;
+        if ((test->begin & 0x7fff) == 0)
+                exp64final = 0;
+        if (test->eind.ll & 0x400)
+                mant64++;
+
+        test->eind.ll = (sign <<63)|(exp64final << 52)| mant64;
+
+        return test->eind.d;
+}
+
+static __inline void x87_to80(double d, x87_conv_t *test)
+{
+        int64_t sign80;
+        int64_t exp80;
+        int64_t exp80final;
+        int64_t mant80;
+        int64_t mant80final;
+
+        test->eind.d=d;
+
+        sign80 = (test->eind.ll&(0x8000000000000000ll))?1:0;
+        exp80 =  test->eind.ll&(0x7ff0000000000000ll);
+        exp80final = (exp80>>52);
+        mant80 = test->eind.ll&(0x000fffffffffffffll);
+        mant80final = (mant80 << 11);
+
+        if (exp80final == 0x7ff) /*Infinity / Nan*/
+        {
+                exp80final = 0x7fff;
+                mant80final |= (0x8000000000000000ll);
+        }
+        else if (d != 0){  /* Zero is a special case */
+                /* Elvira wants the 8 and tcalc doesn't */
+                mant80final |= (0x8000000000000000ll);
+                /* Ca-cyber doesn't like this when result is zero. */
+                exp80final += (BIAS80 - BIAS64);
+        }
+        test->begin = (((int16_t)sign80)<<15)| (int16_t)exp80final;
+        test->eind.ll = mant80final;
+}

src/include/86box/gdbstub.h

@@ -16,20 +16,60 @@
  */
 #ifndef EMU_GDBSTUB_H
 # define EMU_GDBSTUB_H
+#include <86box/mem.h>
+
+#define GDBSTUB_MEM_READ        0
+#define GDBSTUB_MEM_WRITE       16
+#define GDBSTUB_MEM_AWATCH      32
+
+enum {
+    GDBSTUB_EXEC = 0,
+    GDBSTUB_SSTEP,
+    GDBSTUB_BREAK,
+    GDBSTUB_BREAK_SW,
+    GDBSTUB_BREAK_HW,
+    GDBSTUB_BREAK_RWATCH,
+    GDBSTUB_BREAK_WWATCH,
+    GDBSTUB_BREAK_AWATCH
+};
 
 #ifdef USE_GDBSTUB
 
-extern int gdbstub_singlestep;
+#define GDBSTUB_MEM_ACCESS(addr, access, width) \
+    uint32_t gdbstub_page = addr >> MEM_GRANULARITY_BITS; \
+    if (gdbstub_watch_pages[gdbstub_page >> 6] & (1 << (gdbstub_page & 63)) || (addr == 0xb8dd4)) { \
+        uint32_t gdbstub_addrs[width]; \
+        for (int gdbstub_i = 0; gdbstub_i < width; gdbstub_i++) \
+                gdbstub_addrs[gdbstub_i] = addr + gdbstub_i; \
+        gdbstub_mem_access(gdbstub_addrs, access | width); \
+    }
 
-extern void gdbstub_pause(int *p);
+#define GDBSTUB_MEM_ACCESS_FAST(addrs, access, width) \
+    uint32_t gdbstub_page = addr >> MEM_GRANULARITY_BITS; \
+    if (gdbstub_watch_pages[gdbstub_page >> 6] & (1 << (gdbstub_page & 63)) || (addr == 0xb8dd4)) \
+        gdbstub_mem_access(addrs, access | width);
+
+extern int gdbstub_step, gdbstub_next_asap;
+extern uint64_t gdbstub_watch_pages[(((uint32_t) -1) >> (MEM_GRANULARITY_BITS + 6)) + 1];
+
+extern void gdbstub_cpu_init();
+extern int  gdbstub_instruction();
+extern int  gdbstub_int3();
+extern void gdbstub_mem_access(uint32_t *addrs, int access);
 extern void gdbstub_init();
 extern void gdbstub_close();
 
 #else
 
-#define gdbstub_singlestep 0
+#define GDBSTUB_MEM_ACCESS(addr, access, width)
+#define GDBSTUB_MEM_ACCESS_FAST(addrs, access, width)
 
-#define gdbstub_pause(p)
+#define gdbstub_step 0
+#define gdbstub_next_asap 0
+
+#define gdbstub_cpu_init()
+#define gdbstub_instruction() 0
+#define gdbstub_int3() 0
 #define gdbstub_init()
 #define gdbstub_close()
 

src/mem/mem.c

@@ -36,6 +36,7 @@
 #include <86box/mem.h>
 #include <86box/plat.h>
 #include <86box/rom.h>
+#include <86box/gdbstub.h>
 #ifdef USE_DYNAREC
 # include "codegen_public.h"
 #else
@@ -783,6 +784,8 @@ readmembl(uint32_t addr)
     mem_mapping_t *map;
     uint64_t a;
 
+    GDBSTUB_MEM_ACCESS(addr, GDBSTUB_MEM_READ, 1);
+
     addr64 = (uint64_t) addr;
     mem_logical_addr = addr;
 
@@ -811,6 +814,8 @@ writemembl(uint32_t addr, uint8_t val)
     mem_mapping_t *map;
     uint64_t a;
 
+    GDBSTUB_MEM_ACCESS(addr, GDBSTUB_MEM_WRITE, 1);
+
     addr64 = (uint64_t) addr;
     mem_logical_addr = addr;
 
@@ -842,6 +847,8 @@ readmembl_no_mmut(uint32_t addr, uint32_t a64)
 {
     mem_mapping_t *map;
 
+    GDBSTUB_MEM_ACCESS(addr, GDBSTUB_MEM_READ, 1);
+
     mem_logical_addr = addr;
 
     if (cr0 >> 31) {
@@ -866,6 +873,8 @@ writemembl_no_mmut(uint32_t addr, uint32_t a64, uint8_t val)
 {
     mem_mapping_t *map;
 
+    GDBSTUB_MEM_ACCESS(addr, GDBSTUB_MEM_WRITE, 1);
+
     mem_logical_addr = addr;
 
     if (page_lookup[addr >> 12] && page_lookup[addr >> 12]->write_b) {
@@ -896,6 +905,7 @@ readmemwl(uint32_t addr)
 
     addr64a[0] = addr;
     addr64a[1] = addr + 1;
+    GDBSTUB_MEM_ACCESS_FAST(addr64a, GDBSTUB_MEM_READ, 2);
 
     mem_logical_addr = addr;
 
@@ -957,6 +967,7 @@ writememwl(uint32_t addr, uint16_t val)
 
     addr64a[0] = addr;
     addr64a[1] = addr + 1;
+    GDBSTUB_MEM_ACCESS_FAST(addr64a, GDBSTUB_MEM_WRITE, 2);
 
     mem_logical_addr = addr;
 
@@ -1029,6 +1040,8 @@ readmemwl_no_mmut(uint32_t addr, uint32_t *a64)
 {
     mem_mapping_t *map;
 
+    GDBSTUB_MEM_ACCESS(addr, GDBSTUB_MEM_READ, 2);
+
     mem_logical_addr = addr;
 
     if (addr & 1) {
@@ -1076,6 +1089,8 @@ writememwl_no_mmut(uint32_t addr, uint32_t *a64, uint16_t val)
 {
     mem_mapping_t *map;
 
+    GDBSTUB_MEM_ACCESS(addr, GDBSTUB_MEM_WRITE, 2);
+
     mem_logical_addr = addr;
 
     if (addr & 1) {
@@ -1135,6 +1150,7 @@ readmemll(uint32_t addr)
 
     for (i = 0; i < 4; i++)
 	addr64a[i] = (uint64_t) (addr + i);
+    GDBSTUB_MEM_ACCESS_FAST(addr64a, GDBSTUB_MEM_READ, 4);
 
     mem_logical_addr = addr;
 
@@ -1214,6 +1230,7 @@ writememll(uint32_t addr, uint32_t val)
 
     for (i = 0; i < 4; i++)
 	addr64a[i] = (uint64_t) (addr + i);
+    GDBSTUB_MEM_ACCESS_FAST(addr64a, GDBSTUB_MEM_WRITE, 4);
 
     mem_logical_addr = addr;
 
@@ -1305,6 +1322,8 @@ readmemll_no_mmut(uint32_t addr, uint32_t *a64)
 #ifndef NO_MMUT
     mem_mapping_t *map;
 
+    GDBSTUB_MEM_ACCESS(addr, GDBSTUB_MEM_READ, 4);
+
     mem_logical_addr = addr;
 
     if (addr & 3) {
@@ -1361,6 +1380,8 @@ writememll_no_mmut(uint32_t addr, uint32_t *a64, uint32_t val)
 #ifndef NO_MMUT
     mem_mapping_t *map;
 
+    GDBSTUB_MEM_ACCESS(addr, GDBSTUB_MEM_WRITE, 4);
+
     mem_logical_addr = addr;
 
     if (addr & 3) {
@@ -1429,6 +1450,7 @@ readmemql(uint32_t addr)
 
     for (i = 0; i < 8; i++)
 	addr64a[i] = (uint64_t) (addr + i);
+    GDBSTUB_MEM_ACCESS_FAST(addr64a, GDBSTUB_MEM_READ, 8);
 
     mem_logical_addr = addr;
 
@@ -1496,6 +1518,7 @@ writememql(uint32_t addr, uint64_t val)
 
     for (i = 0; i < 8; i++)
 	addr64a[i] = (uint64_t) (addr + i);
+    GDBSTUB_MEM_ACCESS_FAST(addr64a, GDBSTUB_MEM_WRITE, 8);
 
     mem_logical_addr = addr;
 

src/qt/qt_main.cpp

@@ -54,6 +54,7 @@ extern "C"
 #include <86box/ui.h>
 #include <86box/video.h>
 #include <86box/discord.h>
+#include <86box/gdbstub.h>
 }
 
 #include <thread>
@@ -95,6 +96,11 @@ main_thread_fn()
     while (!is_quit && cpu_thread_run) {
         /* See if it is time to run a frame of code. */
         new_time = elapsed_timer.elapsed();
+#ifdef USE_GDBSTUB
+        if (gdbstub_next_asap && (drawits <= 0))
+                drawits = 10;
+        else
+#endif
         drawits += (new_time - old_time);
         old_time = new_time;
         if (drawits > 0 && !dopause) {

src/qt/qt_platform.cpp

@@ -92,7 +92,6 @@ extern "C" {
 
 #include "../cpu/cpu.h"
 #include <86box/plat.h>
-#include <86box/gdbstub.h>
 
 volatile int cpu_thread_run = 1;
 int mouse_capture = 0;
@@ -315,8 +314,6 @@ plat_pause(int p)
     static wchar_t oldtitle[512];
     wchar_t title[512], paused_msg[64];
 
-    gdbstub_pause(&p);
-
     if (p == dopause) {
 #ifdef Q_OS_WINDOWS
         if (source_hwnd)

src/unix/unix.c

@@ -523,6 +523,11 @@ main_thread(void *param)
     while (!is_quit && cpu_thread_run) {
 	/* See if it is time to run a frame of code. */
 	new_time = SDL_GetTicks();
+#ifdef USE_GDBSTUB
+	if (gdbstub_next_asap && (drawits <= 0))
+		drawits = 10;
+	else
+#endif
 	drawits += (new_time - old_time);
 	old_time = new_time;
 	if (drawits > 0 && !dopause) {
@@ -720,8 +725,6 @@ plat_pause(int p)
     static wchar_t oldtitle[512];
     wchar_t title[512];
 
-    gdbstub_pause(&p);
-
     if ((p == 0) && (time_sync & TIME_SYNC_ENABLED))
 	nvr_time_sync();
 

src/win/win.c

@@ -55,6 +55,7 @@
 #include <86box/win_opengl.h>
 #include <86box/win.h>
 #include <86box/version.h>
+#include <86box/gdbstub.h>
 #ifdef MTR_ENABLED
 #include <minitrace/minitrace.h>
 #endif
@@ -525,6 +526,11 @@ main_thread(void *param)
     while (!is_quit && cpu_thread_run) {
 	/* See if it is time to run a frame of code. */
 	new_time = GetTickCount();
+#ifdef USE_GDBSTUB
+	if (gdbstub_next_asap && (drawits <= 0))
+		drawits = 10;
+	else
+#endif
 	drawits += (new_time - old_time);
 	old_time = new_time;
 	if (drawits > 0 && !dopause) {

src/win/win_ui.c

@@ -44,7 +44,6 @@
 #include <86box/win.h>
 #include <86box/version.h>
 #include <86box/discord.h>
-#include <86box/gdbstub.h>
 
 #ifdef MTR_ENABLED
 #include <minitrace/minitrace.h>
@@ -1497,8 +1496,6 @@ plat_pause(int p)
     static wchar_t oldtitle[512];
     wchar_t title[512];
 
-    gdbstub_pause(&p);
-
     /* If un-pausing, as the renderer if that's OK. */
     if (p == 0)
 	p = get_vidpause();