diff --git a/gdbstub.c b/gdbstub.c
index 9ede3de..4879055 100644
--- a/gdbstub.c
+++ b/gdbstub.c
@@ -530,8 +530,6 @@
 #endif
 static const int gpr_map32[8] = { 0, 1, 2, 3, 4, 5, 6, 7 };
 
-#define NUM_CORE_REGS (CPU_NB_REGS * 2 + 25)
-
 #define IDX_IP_REG      CPU_NB_REGS
 #define IDX_FLAGS_REG   (IDX_IP_REG + 1)
 #define IDX_SEG_REGS    (IDX_FLAGS_REG + 1)
@@ -732,7 +730,6 @@
    historical mishap the FP registers appear in between core integer
    regs and PC, MSR, CR, and so forth.  We hack round this by giving the
    FP regs zero size when talking to a newer gdb.  */
-#define NUM_CORE_REGS 71
 #if defined (TARGET_PPC64)
 #define GDB_CORE_XML "power64-core.xml"
 #else
@@ -837,12 +834,6 @@
 
 #elif defined (TARGET_SPARC)
 
-#if defined(TARGET_SPARC64) && !defined(TARGET_ABI32)
-#define NUM_CORE_REGS 86
-#else
-#define NUM_CORE_REGS 72
-#endif
-
 #ifdef TARGET_ABI32
 #define GET_REGA(val) GET_REG32(val)
 #else
@@ -1030,7 +1021,6 @@
    the FPA registers appear in between core integer regs and the CPSR.
    We hack round this by giving the FPA regs zero size when talking to a
    newer gdb.  */
-#define NUM_CORE_REGS 26
 #define GDB_CORE_XML "arm-core.xml"
 
 static int cpu_gdb_read_register(CPUARMState *env, uint8_t *mem_buf, int n)
@@ -1104,8 +1094,6 @@
 
 #elif defined (TARGET_M68K)
 
-#define NUM_CORE_REGS 18
-
 #define GDB_CORE_XML "cf-core.xml"
 
 static int cpu_gdb_read_register(CPUM68KState *env, uint8_t *mem_buf, int n)
@@ -1157,8 +1145,6 @@
 }
 #elif defined (TARGET_MIPS)
 
-#define NUM_CORE_REGS 73
-
 static int cpu_gdb_read_register(CPUMIPSState *env, uint8_t *mem_buf, int n)
 {
     if (n < 32) {
@@ -1285,8 +1271,6 @@
 }
 #elif defined(TARGET_OPENRISC)
 
-#define NUM_CORE_REGS (32 + 3)
-
 static int cpu_gdb_read_register(CPUOpenRISCState *env, uint8_t *mem_buf, int n)
 {
     if (n < 32) {
@@ -1312,9 +1296,11 @@
 static int cpu_gdb_write_register(CPUOpenRISCState *env,
                                   uint8_t *mem_buf, int n)
 {
+    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);
+    CPUClass *cc = CPU_GET_CLASS(cpu);
     uint32_t tmp;
 
-    if (n > NUM_CORE_REGS) {
+    if (n > cc->gdb_num_core_regs) {
         return 0;
     }
 
@@ -1347,8 +1333,6 @@
 /* Hint: Use "set architecture sh4" in GDB to see fpu registers */
 /* FIXME: We should use XML for this.  */
 
-#define NUM_CORE_REGS 59
-
 static int cpu_gdb_read_register(CPUSH4State *env, uint8_t *mem_buf, int n)
 {
     switch (n) {
@@ -1465,8 +1449,6 @@
 }
 #elif defined (TARGET_MICROBLAZE)
 
-#define NUM_CORE_REGS (32 + 5)
-
 static int cpu_gdb_read_register(CPUMBState *env, uint8_t *mem_buf, int n)
 {
     if (n < 32) {
@@ -1479,9 +1461,11 @@
 
 static int cpu_gdb_write_register(CPUMBState *env, uint8_t *mem_buf, int n)
 {
+    MicroBlazeCPU *cpu = mb_env_get_cpu(env);
+    CPUClass *cc = CPU_GET_CLASS(cpu);
     uint32_t tmp;
 
-    if (n > NUM_CORE_REGS) {
+    if (n > cc->gdb_num_core_regs) {
         return 0;
     }
 
@@ -1496,8 +1480,6 @@
 }
 #elif defined (TARGET_CRIS)
 
-#define NUM_CORE_REGS 49
-
 static int
 read_register_crisv10(CPUCRISState *env, uint8_t *mem_buf, int n)
 {
@@ -1605,8 +1587,6 @@
 }
 #elif defined (TARGET_ALPHA)
 
-#define NUM_CORE_REGS 67
-
 static int cpu_gdb_read_register(CPUAlphaState *env, uint8_t *mem_buf, int n)
 {
     uint64_t val;
@@ -1675,8 +1655,6 @@
 }
 #elif defined (TARGET_S390X)
 
-#define NUM_CORE_REGS  S390_NUM_REGS
-
 static int cpu_gdb_read_register(CPUS390XState *env, uint8_t *mem_buf, int n)
 {
     uint64_t val;
@@ -1740,7 +1718,6 @@
 #elif defined (TARGET_LM32)
 
 #include "hw/lm32/lm32_pic.h"
-#define NUM_CORE_REGS (32 + 7)
 
 static int cpu_gdb_read_register(CPULM32State *env, uint8_t *mem_buf, int n)
 {
@@ -1770,9 +1747,11 @@
 
 static int cpu_gdb_write_register(CPULM32State *env, uint8_t *mem_buf, int n)
 {
+    LM32CPU *cpu = lm32_env_get_cpu(env);
+    CPUClass *cc = CPU_GET_CLASS(cpu);
     uint32_t tmp;
 
-    if (n > NUM_CORE_REGS) {
+    if (n > cc->gdb_num_core_regs) {
         return 0;
     }
 
@@ -1806,14 +1785,6 @@
 }
 #elif defined(TARGET_XTENSA)
 
-/* Use num_core_regs to see only non-privileged registers in an unmodified gdb.
- * Use num_regs to see all registers. gdb modification is required for that:
- * reset bit 0 in the 'flags' field of the registers definitions in the
- * gdb/xtensa-config.c inside gdb source tree or inside gdb overlay.
- */
-#define NUM_CORE_REGS (env->config->gdb_regmap.num_regs)
-#define num_g_regs NUM_CORE_REGS
-
 static int cpu_gdb_read_register(CPUXtensaState *env, uint8_t *mem_buf, int n)
 {
     const XtensaGdbReg *reg = env->config->gdb_regmap.reg + n;
@@ -1896,8 +1867,6 @@
 }
 #else
 
-#define NUM_CORE_REGS 0
-
 static int cpu_gdb_read_register(CPUArchState *env, uint8_t *mem_buf, int n)
 {
     return 0;
@@ -1910,10 +1879,6 @@
 
 #endif
 
-#if !defined(TARGET_XTENSA)
-static int num_g_regs = NUM_CORE_REGS;
-#endif
-
 #ifdef GDB_CORE_XML
 /* Encode data using the encoding for 'x' packets.  */
 static int memtox(char *buf, const char *mem, int len)
@@ -1982,11 +1947,13 @@
 
 static int gdb_read_register(CPUState *cpu, uint8_t *mem_buf, int reg)
 {
+    CPUClass *cc = CPU_GET_CLASS(cpu);
     CPUArchState *env = cpu->env_ptr;
     GDBRegisterState *r;
 
-    if (reg < NUM_CORE_REGS)
+    if (reg < cc->gdb_num_core_regs) {
         return cpu_gdb_read_register(env, mem_buf, reg);
+    }
 
     for (r = cpu->gdb_regs; r; r = r->next) {
         if (r->base_reg <= reg && reg < r->base_reg + r->num_regs) {
@@ -1998,11 +1965,13 @@
 
 static int gdb_write_register(CPUState *cpu, uint8_t *mem_buf, int reg)
 {
+    CPUClass *cc = CPU_GET_CLASS(cpu);
     CPUArchState *env = cpu->env_ptr;
     GDBRegisterState *r;
 
-    if (reg < NUM_CORE_REGS)
+    if (reg < cc->gdb_num_core_regs) {
         return cpu_gdb_write_register(env, mem_buf, reg);
+    }
 
     for (r = cpu->gdb_regs; r; r = r->next) {
         if (r->base_reg <= reg && reg < r->base_reg + r->num_regs) {
@@ -2012,7 +1981,6 @@
     return 0;
 }
 
-#if !defined(TARGET_XTENSA)
 /* Register a supplemental set of CPU registers.  If g_pos is nonzero it
    specifies the first register number and these registers are included in
    a standard "g" packet.  Direction is relative to gdb, i.e. get_reg is
@@ -2025,7 +1993,6 @@
 {
     GDBRegisterState *s;
     GDBRegisterState **p;
-    static int last_reg = NUM_CORE_REGS;
 
     p = &cpu->gdb_regs;
     while (*p) {
@@ -2036,25 +2003,22 @@
     }
 
     s = g_new0(GDBRegisterState, 1);
-    s->base_reg = last_reg;
+    s->base_reg = cpu->gdb_num_regs;
     s->num_regs = num_regs;
     s->get_reg = get_reg;
     s->set_reg = set_reg;
     s->xml = xml;
 
     /* Add to end of list.  */
-    last_reg += num_regs;
+    cpu->gdb_num_regs += num_regs;
     *p = s;
     if (g_pos) {
         if (g_pos != s->base_reg) {
             fprintf(stderr, "Error: Bad gdb register numbering for '%s'\n"
                     "Expected %d got %d\n", xml, g_pos, s->base_reg);
-        } else {
-            num_g_regs = last_reg;
         }
     }
 }
-#endif
 
 #ifndef CONFIG_USER_ONLY
 static const int xlat_gdb_type[] = {
@@ -2184,9 +2148,6 @@
 
 static int gdb_handle_packet(GDBState *s, const char *line_buf)
 {
-#ifdef TARGET_XTENSA
-    CPUArchState *env;
-#endif
     CPUState *cpu;
     const char *p;
     uint32_t thread;
@@ -2334,11 +2295,8 @@
         break;
     case 'g':
         cpu_synchronize_state(s->g_cpu);
-#ifdef TARGET_XTENSA
-        env = s->g_cpu->env_ptr;
-#endif
         len = 0;
-        for (addr = 0; addr < num_g_regs; addr++) {
+        for (addr = 0; addr < s->g_cpu->gdb_num_regs; addr++) {
             reg_size = gdb_read_register(s->g_cpu, mem_buf + len, addr);
             len += reg_size;
         }
@@ -2347,13 +2305,10 @@
         break;
     case 'G':
         cpu_synchronize_state(s->g_cpu);
-#ifdef TARGET_XTENSA
-        env = s->g_cpu->env_ptr;
-#endif
         registers = mem_buf;
         len = strlen(p) / 2;
         hextomem((uint8_t *)registers, p, len);
-        for (addr = 0; addr < num_g_regs && len > 0; addr++) {
+        for (addr = 0; addr < s->g_cpu->gdb_num_regs && len > 0; addr++) {
             reg_size = gdb_write_register(s->g_cpu, registers, addr);
             len -= reg_size;
             registers += reg_size;