--- np2/i386c/ia32/cpu_mem.c	2004/01/07 14:49:10	1.4
+++ np2/i386c/ia32/cpu_mem.c	2004/02/20 16:09:04	1.11
@@ -1,4 +1,4 @@
-/*	$Id: cpu_mem.c,v 1.4 2004/01/07 14:49:10 monaka Exp $	*/
+/*	$Id: cpu_mem.c,v 1.11 2004/02/20 16:09:04 monaka Exp $	*/
 
 /*
  * Copyright (c) 2002-2003 NONAKA Kimihiro
@@ -31,210 +31,199 @@
 #include "cpu.h"
 #include "memory.h"
 
-// ¤¢¤È¤Ç¡Ä
-// extern DWORD cpumem_addrmask;		// -> CPU_STAT_ADRSMASK
-
-BYTE *cpumem = 0;
-DWORD extmem_size = 0;
-BYTE protectmem_size = 0;
-
-/*
- * initialize 1MB-16MB memory
- */
-
-int
-init_cpumem(BYTE usemem)
-{
-	DWORD size;
-
-	if (usemem > 13)
-		usemem = 13;
-	size = usemem << 20;
-
-	if (extmem_size != size - (LOWMEM - 0x100000)) {
-		if (cpumem) {
-			free(cpumem);
-			cpumem = 0;
-		}
-		if (size <= LOWMEM - 0x100000) {
-			extmem_size = 0;
-			cpumem = 0;
-		} else {
-			extmem_size = size - (LOWMEM - 0x100000);
-			cpumem = (BYTE *)malloc(extmem_size);
-			if (cpumem == NULL) {
-				protectmem_size = 0;
-				return FAILURE;
-			}
-			memset(cpumem, 0, extmem_size);
-		}
-	}
-	protectmem_size = usemem;
-	return SUCCESS;
-}
-
 
 /*
  * memory access check
  */
 void
-cpu_memoryread_check(descriptor_t* sd, DWORD madr, DWORD length, int e)
+cpu_memoryread_check(descriptor_t *sd, UINT32 offset, UINT length, int e)
 {
+	UINT32 uplimit;
 
 	if (CPU_STAT_PM) {
 		/* invalid */
 		if (!sd->valid) {
+			VERBOSE(("cpu_memoryread_check: invalid"));
 			EXCEPTION(GP_EXCEPTION, 0);
 		}
 
 		/* not present */
 		if (!sd->p) {
+			VERBOSE(("cpu_memoryread_check: not present"));
 			EXCEPTION(e, 0);
 		}
+	}
 
-		switch (sd->type) {
-		case 0:	 case 1:	/* ro */
-		case 2:  case 3:	/* rw */
-		case 10: case 11:	/* rx */
-		case 14: case 15:	/* rxc */
-			if ((madr > sd->u.seg.segend - length + 1)
-			    || (length - 1 > sd->u.seg.limit)) {
-				EXCEPTION(e, 0);
-			}
-			break;
-
-		case 4:  case 5:	/* ro (expand down) */
-		case 6:  case 7:	/* rw (expand down) */
-		{
-			DWORD uplimit = sd->d ? 0xffffffff : 0x0000ffff;
-			if ((madr <= sd->u.seg.segend)
-			    || (madr > uplimit)
-			    || (uplimit - madr < length - 1)) {
-				EXCEPTION(e, 0);
-			}
+	switch (sd->type) {
+	case 0:	 case 1:	/* ro */
+	case 2:  case 3:	/* rw */
+	case 10: case 11:	/* rx */
+	case 14: case 15:	/* rxc */
+		if (offset > sd->u.seg.limit - length + 1) {
+			VERBOSE(("cpu_memoryread_check: offset(%08x) > sd->u.seg.limit(%08x) - length(%08x) + 1", offset, sd->u.seg.limit, length));
+			EXCEPTION(e, 0);
 		}
-			break;
+		if (length - 1 > sd->u.seg.limit) {
+			VERBOSE(("cpu_memoryread_check: length(%08x) - 1 > sd->u.seg.limit(%08x)", length, sd->u.seg.limit));
+			EXCEPTION(e, 0);
+		}
+		break;
 
-		default:
+	case 4:  case 5:	/* ro (expand down) */
+	case 6:  case 7:	/* rw (expand down) */
+		uplimit = sd->d ? 0xffffffff : 0x0000ffff;
+		if (offset <= sd->u.seg.limit) {
+			VERBOSE(("cpu_memoryread_check: offset(%08x) <= sd->u.seg.limit(%08x)", offset, sd->u.seg.limit));
+			EXCEPTION(e, 0);
+		}
+		if (offset > uplimit) {
+			VERBOSE(("cpu_memoryread_check: offset(%08x) > uplimit(%08x)", offset, uplimit));
 			EXCEPTION(e, 0);
-			break;
 		}
+		if (uplimit - offset < length - 1) {
+			VERBOSE(("cpu_memoryread_check: uplimit(%08x) - offset(%08x) < length(%08x) - 1", uplimit, offset, length));
+			EXCEPTION(e, 0);
+		}
+		break;
+
+	default:
+		VERBOSE(("cpu_memoryread_check: invalid type (type = %d)", sd->type));
+		EXCEPTION(e, 0);
+		break;
 	}
-	sd->flag |= CPU_DESC_READABLE;
+	sd->flag |= CPU_DESC_FLAG_READABLE;
 }
 
 void
-cpu_memorywrite_check(descriptor_t* sd, DWORD madr, DWORD length, int e)
+cpu_memorywrite_check(descriptor_t *sd, UINT32 offset, UINT length, int e)
 {
+	UINT32 uplimit;
 
 	if (CPU_STAT_PM) {
 		/* invalid */
 		if (!sd->valid) {
+			VERBOSE(("cpu_memorywrite_check: invalid"));
 			EXCEPTION(GP_EXCEPTION, 0);
 		}
 
 		/* not present */
 		if (!sd->p) {
+			VERBOSE(("cpu_memorywrite_check: not present"));
 			EXCEPTION(e, 0);
 		}
 
-		switch (sd->type) {
-		case 2: case 3:	/* rw */
-			if ((madr > sd->u.seg.segend - length + 1)
-			    || (length - 1 > sd->u.seg.limit)) {
-				EXCEPTION(e, 0);
-			}
-			break;
+		if (!sd->s) {
+			VERBOSE(("cpu_memorywrite_check: system segment"));
+			EXCEPTION(e, 0);
+		}
+	}
 
-		case 6: case 7:	/* rw (expand down) */
-		{
-			DWORD uplimit = sd->d ? 0xffffffff : 0x0000ffff;
-			if ((madr <= sd->u.seg.segend)
-			    || (madr > uplimit)
-			    || (uplimit - madr < length - 1)) {
-				EXCEPTION(e, 0);
-			}
+	switch (sd->type) {
+	case 2: case 3:	/* rw */
+		if (offset > sd->u.seg.limit - length + 1) {
+			VERBOSE(("cpu_memorywrite_check: offset(%08x) > sd->u.seg.limit(%08x) - length(%08x) + 1", offset, sd->u.seg.limit, length));
+			EXCEPTION(e, 0);
 		}
-			break;
+		if (length - 1 > sd->u.seg.limit) {
+			VERBOSE(("cpu_memorywrite_check: length(%08x) - 1 > sd->u.seg.limit(%08x)", length, sd->u.seg.limit));
+			EXCEPTION(e, 0);
+		}
+		break;
 
-		default:
+	case 6: case 7:	/* rw (expand down) */
+		uplimit = sd->d ? 0xffffffff : 0x0000ffff;
+		if (offset <= sd->u.seg.limit) {
+			VERBOSE(("cpu_memorywrite_check: offset(%08x) <= sd->u.seg.limit(%08x)", offset, sd->u.seg.limit));
+			EXCEPTION(e, 0);
+		}
+		if (offset > uplimit) {
+			VERBOSE(("cpu_memorywrite_check: offset(%08x) > uplimit(%08x)", offset, uplimit));
 			EXCEPTION(e, 0);
-			break;
 		}
+		if (uplimit - offset < length - 1) {
+			VERBOSE(("cpu_memorywrite_check: uplimit(%08x) - offset(%08x) < length(%08x) - 1", uplimit, offset, length));
+			EXCEPTION(e, 0);
+		}
+		break;
+
+	default:
+		VERBOSE(("cpu_memorywrite_check: invalid type (type = %d)", sd->type));
+		EXCEPTION(e, 0);
+		break;
 	}
-	sd->flag |= CPU_DESC_WRITABLE;
+	sd->flag |= CPU_DESC_FLAG_WRITABLE;
 }
 
 BOOL
-cpu_stack_push_check(descriptor_t* sdp, DWORD esp, DWORD length)
+cpu_stack_push_check(descriptor_t *sd, UINT32 esp, UINT length)
 {
+	UINT32 limit;
 
-	if (!CPU_STAT_PM)
-		return TRUE;
-
-	if (!sdp->valid || !sdp->p)
-		return FALSE;
-#ifdef _DEBUG
-	if (!sdp->s || sdp->u.seg.c || !sdp->u.seg.wr)
-		return FALSE;
-#endif
-
-	if (!sdp->d)
-		esp &= 0xffff;
-	if (sdp->u.seg.ec) {
-		DWORD limit = (sdp->d) ? 0xffffffff : 0xffff;
-		if ((esp == 0)
-		 || (esp < length)
-		 || (esp - length <= sdp->u.seg.segend)
-		 || (esp > limit))
+	if (CPU_STAT_PM) {
+		if (!sd->valid || !sd->p)
 			return FALSE;
-	} else {
-		/* expand-up stack */
-		if (esp == 0) {
-			if ((sdp->d && (sdp->u.seg.segend != 0xffffffff))
-			 || (!sdp->d && (sdp->u.seg.segend != 0xffff)))
-				return FALSE;
+		if (!sd->s || sd->u.seg.c || !sd->u.seg.wr)
+			return FALSE;
+
+		if (!sd->d) {
+			esp &= 0xffff;
+			limit = 0xffff;
 		} else {
-			if ((esp < length)
-			 || (esp - 1 > sdp->u.seg.segend))
+			limit = 0xffffffff;
+		}
+		if (sd->u.seg.ec) {
+			/* expand-down stack */
+			if ((esp == 0)
+			 || (esp < length)
+			 || (esp - length <= sd->u.seg.limit)
+			 || (esp > limit))
 				return FALSE;
+		} else {
+			/* expand-up stack */
+			if (esp == 0) {
+				if ((sd->d && (sd->u.seg.segend != 0xffffffff))
+				 || (!sd->d && (sd->u.seg.segend != 0xffff)))
+					return FALSE;
+			} else {
+				if ((esp < length)
+				 || (esp - 1 > sd->u.seg.limit))
+					return FALSE;
+			}
 		}
 	}
 	return TRUE;
 }
 
 BOOL
-cpu_stack_pop_check(descriptor_t* sdp, DWORD esp, DWORD length)
+cpu_stack_pop_check(descriptor_t *sd, UINT32 esp, UINT length)
 {
-	DWORD limit;
-
-	if (!CPU_STAT_PM)
-		return TRUE;
+	UINT32 limit;
 
-	if (!sdp->valid || !sdp->p)
-		return FALSE;
-#ifdef _DEBUG
-	if (!sdp->s || sdp->u.seg.c || !sdp->u.seg.wr)
-		return FALSE;
-#endif
-
-	if (!sdp->d) {
-		esp &= 0xffff;
-		limit = 0xffff;
-	} else {
-		limit = 0xffffffff;
-	}
-	if (sdp->u.seg.ec) {
-		if ((esp == limit)
-		 || ((limit  - esp) + 1 < length))
+	if (CPU_STAT_PM) {
+		if (!sd->valid || !sd->p)
 			return FALSE;
-	} else {
-		/* expand-up stack */
-		if ((esp == limit)
-		 || (sdp->u.seg.segend == 0)
-		 || (esp > sdp->u.seg.segend)
-		 || ((sdp->u.seg.segend - esp) + 1 < length))
+		if (!sd->s || sd->u.seg.c || !sd->u.seg.wr)
 			return FALSE;
+
+		if (!sd->d) {
+			esp &= 0xffff;
+			limit = 0xffff;
+		} else {
+			limit = 0xffffffff;
+		}
+		if (sd->u.seg.ec) {
+			/* expand-down stack */
+			if ((esp == limit)
+			 || ((limit - esp) + 1 < length))
+				return FALSE;
+		} else {
+			/* expand-up stack */
+			if ((esp == limit)
+			 || (sd->u.seg.segend == 0)
+			 || (esp > sd->u.seg.limit)
+			 || ((sd->u.seg.limit - esp) + 1 < length))
+				return FALSE;
+		}
 	}
 	return TRUE;
 }
@@ -243,17 +232,15 @@ cpu_stack_pop_check(descriptor_t* sdp, D
 /*
  * code fetch
  */
-BYTE MEMCALL
-cpu_codefetch(DWORD madr)
+UINT8 MEMCALL
+cpu_codefetch(UINT32 offset)
 {
 	descriptor_t *sd;
-	DWORD addr;
+	UINT32 addr;
 
 	sd = &CPU_STAT_SREG(CPU_CS_INDEX);
-	if (!CPU_INST_AS32)
-		madr &= 0xffff;
-	if (madr <= sd->u.seg.segend) {
-		addr = CPU_STAT_SREGBASE(CPU_CS_INDEX) + madr;
+	if (offset <= sd->u.seg.limit) {
+		addr = CPU_STAT_SREGBASE(CPU_CS_INDEX) + offset;
 		if (!CPU_STAT_PM)
 			return cpu_memoryread(addr);
 		return cpu_lcmemoryread(addr);
@@ -262,17 +249,15 @@ cpu_codefetch(DWORD madr)
 	return 0;	/* compiler happy */
 }
 
-WORD MEMCALL
-cpu_codefetch_w(DWORD madr)
+UINT16 MEMCALL
+cpu_codefetch_w(UINT32 offset)
 {
 	descriptor_t *sd;
-	DWORD addr;
+	UINT32 addr;
 
 	sd = &CPU_STAT_SREG(CPU_CS_INDEX);
-	if (!CPU_INST_AS32)
-		madr &= 0xffff;
-	if (madr <= sd->u.seg.segend - 1) {
-		addr = CPU_STAT_SREGBASE(CPU_CS_INDEX) + madr;
+	if (offset <= sd->u.seg.limit - 1) {
+		addr = CPU_STAT_SREGBASE(CPU_CS_INDEX) + offset;
 		if (!CPU_STAT_PM)
 			return cpu_memoryread_w(addr);
 		return cpu_lcmemoryread_w(addr);
@@ -281,17 +266,15 @@ cpu_codefetch_w(DWORD madr)
 	return 0;	/* compiler happy */
 }
 
-DWORD MEMCALL
-cpu_codefetch_d(DWORD madr)
+UINT32 MEMCALL
+cpu_codefetch_d(UINT32 offset)
 {
 	descriptor_t *sd;
-	DWORD addr;
+	UINT32 addr;
 
 	sd = &CPU_STAT_SREG(CPU_CS_INDEX);
-	if (!CPU_INST_AS32)
-		madr &= 0xffff;
-	if (madr <= sd->u.seg.segend - 3) {
-		addr = CPU_STAT_SREGBASE(CPU_CS_INDEX) + madr;
+	if (offset <= sd->u.seg.limit - 3) {
+		addr = CPU_STAT_SREGBASE(CPU_CS_INDEX) + offset;
 		if (!CPU_STAT_PM)
 			return cpu_memoryread_d(addr);
 		return cpu_lcmemoryread_d(addr);
@@ -304,317 +287,321 @@ cpu_codefetch_d(DWORD madr)
 /*
  * virtual address -> linear address
  */
-BYTE MEMCALL
-cpu_vmemoryread(int idx, DWORD madr)
+UINT8 MEMCALL
+cpu_vmemoryread(int idx, UINT32 offset)
 {
 	descriptor_t *sd;
-	DWORD addr;
+	UINT32 addr;
+	int exc;
 
 	__ASSERT((unsigned int)idx < CPU_SEGREG_NUM);
 
 	sd = &CPU_STAT_SREG(idx);
 	if (!sd->valid) {
-		EXCEPTION(GP_EXCEPTION, 0);
+		exc = GP_EXCEPTION;
+		goto err;
 	}
 
-	if (!CPU_INST_AS32)
-		madr &= 0xffff;
-	for (;;) {
-		if ((sd->flag & CPU_DESC_READABLE)
-		    || (madr <= sd->u.seg.segend)) {
-			addr = CPU_STAT_SREGBASE(idx) + madr;
-			if (!CPU_STAT_PM)
-				return cpu_memoryread(addr);
-			return cpu_lmemoryread(addr);
-		}
-		cpu_memoryread_check(sd, madr, 1,
+	if (!(sd->flag & CPU_DESC_FLAG_READABLE)) {
+		cpu_memoryread_check(sd, offset, 1,
 		    (idx == CPU_SS_INDEX) ? SS_EXCEPTION : GP_EXCEPTION);
+	} else {
+		switch (sd->type) {
+		case 4: case 5: case 6: case 7:
+			if (offset <= sd->u.seg.limit) {
+				if (idx == CPU_SS_INDEX)
+					exc = SS_EXCEPTION;
+				else
+					exc = GP_EXCEPTION;
+				goto err;
+			}
+			break;
+
+		default:
+			if (offset > sd->u.seg.limit) {
+				if (idx == CPU_SS_INDEX)
+					exc = SS_EXCEPTION;
+				else
+					exc = GP_EXCEPTION;
+				goto err;
+			}
+			break;
+		}
 	}
-	/*NOTREACHED*/
+	addr = CPU_STAT_SREGBASE(idx) + offset;
+	if (!CPU_STAT_PM)
+		return cpu_memoryread(addr);
+	return cpu_lmemoryread(addr, CPU_STAT_USER_MODE);
+
+err:
+	EXCEPTION(exc, 0);
+	return 0;	/* compiler happy */
 }
 
-WORD MEMCALL
-cpu_vmemoryread_w(int idx, DWORD madr)
+UINT16 MEMCALL
+cpu_vmemoryread_w(int idx, UINT32 offset)
 {
 	descriptor_t *sd;
-	DWORD addr;
+	UINT32 addr;
+	int exc;
 
 	__ASSERT((unsigned int)idx < CPU_SEGREG_NUM);
 
 	sd = &CPU_STAT_SREG(idx);
 	if (!sd->valid) {
-		EXCEPTION(GP_EXCEPTION, 0);
+		exc = GP_EXCEPTION;
+		goto err;
 	}
 
-	if (!CPU_INST_AS32)
-		madr &= 0xffff;
-	for (;;) {
-		if ((sd->flag & CPU_DESC_READABLE)
-		    || (madr <= sd->u.seg.segend - 1)) {
-			addr = CPU_STAT_SREGBASE(idx) + madr;
-			if (!CPU_STAT_PM)
-				return cpu_memoryread_w(addr);
-			return cpu_lmemoryread_w(addr);
-		}
-		cpu_memoryread_check(sd, madr, 2,
+	if (!(sd->flag & CPU_DESC_FLAG_READABLE)) {
+		cpu_memoryread_check(sd, offset, 2,
 		    (idx == CPU_SS_INDEX) ? SS_EXCEPTION : GP_EXCEPTION);
-	}
-	/*NOTREACHED*/
+	} else {
+		switch (sd->type) {
+		case 4: case 5: case 6: case 7:
+			if (offset - 1 <= sd->u.seg.limit) {
+				if (idx == CPU_SS_INDEX)
+					exc = SS_EXCEPTION;
+				else
+					exc = GP_EXCEPTION;
+				goto err;
+			}
+			break;
+
+		default:
+			if (offset > sd->u.seg.limit - 1) {
+				if (idx == CPU_SS_INDEX)
+					exc = SS_EXCEPTION;
+				else
+					exc = GP_EXCEPTION;
+				goto err;
+			}
+			break;
+		}
+	} 
+	addr = CPU_STAT_SREGBASE(idx) + offset;
+	if (!CPU_STAT_PM)
+		return cpu_memoryread_w(addr);
+	return cpu_lmemoryread_w(addr, CPU_STAT_USER_MODE);
+
+err:
+	EXCEPTION(exc, 0);
+	return 0;	/* compiler happy */
 }
 
-DWORD MEMCALL
-cpu_vmemoryread_d(int idx, DWORD madr)
+UINT32 MEMCALL
+cpu_vmemoryread_d(int idx, UINT32 offset)
 {
 	descriptor_t *sd;
-	DWORD addr;
+	UINT32 addr;
+	int exc;
 
 	__ASSERT((unsigned int)idx < CPU_SEGREG_NUM);
 
 	sd = &CPU_STAT_SREG(idx);
 	if (!sd->valid) {
-		EXCEPTION(GP_EXCEPTION, 0);
+		exc = GP_EXCEPTION;
+		goto err;
 	}
 
-	if (!CPU_INST_AS32)
-		madr &= 0xffff;
-	for (;;) {
-		if ((sd->flag & CPU_DESC_READABLE)
-		    || (madr <= sd->u.seg.segend - 3)) {
-			addr = CPU_STAT_SREGBASE(idx) + madr;
-			if (!CPU_STAT_PM)
-				return cpu_memoryread_d(addr);
-			return cpu_lmemoryread_d(addr);
-		}
-		cpu_memoryread_check(sd, madr, 4,
+	if (!(sd->flag & CPU_DESC_FLAG_READABLE)) {
+		cpu_memoryread_check(sd, offset, 4,
 		    (idx == CPU_SS_INDEX) ? SS_EXCEPTION : GP_EXCEPTION);
+	} else {
+		switch (sd->type) {
+		case 4: case 5: case 6: case 7:
+			if (offset - 3 <= sd->u.seg.limit) {
+				if (idx == CPU_SS_INDEX)
+					exc = SS_EXCEPTION;
+				else
+					exc = GP_EXCEPTION;
+				goto err;
+			}
+			break;
+
+		default:
+			if (offset > sd->u.seg.limit - 3) {
+				if (idx == CPU_SS_INDEX)
+					exc = SS_EXCEPTION;
+				else
+					exc = GP_EXCEPTION;
+				goto err;
+			}
+			break;
+		}
 	}
-	/*NOTREACHED*/
+	addr = CPU_STAT_SREGBASE(idx) + offset;
+	if (!CPU_STAT_PM)
+		return cpu_memoryread_d(addr);
+	return cpu_lmemoryread_d(addr, CPU_STAT_USER_MODE);
+
+err:
+	EXCEPTION(exc, 0);
+	return 0;	/* compiler happy */
 }
 
 /* vaddr memory write */
 void MEMCALL
-cpu_vmemorywrite(int idx, DWORD madr, BYTE val)
+cpu_vmemorywrite(int idx, UINT32 offset, UINT8 val)
 {
 	descriptor_t *sd;
-	DWORD addr;
+	UINT32 addr;
+	int exc;
 
 	__ASSERT((unsigned int)idx < CPU_SEGREG_NUM);
 
 	sd = &CPU_STAT_SREG(idx);
 	if (!sd->valid) {
-		EXCEPTION(GP_EXCEPTION, 0);
+		exc = GP_EXCEPTION;
+		goto err;
 	}
 
-	if (!CPU_INST_AS32)
-		madr &= 0xffff;
-	for (;;) {
-		if ((sd->flag & CPU_DESC_WRITABLE)
-		    || (madr <= sd->u.seg.segend)) {
-			addr = CPU_STAT_SREGBASE(idx) + madr;
-			if (!CPU_STAT_PM) {
-				/* real mode */
-				cpu_memorywrite(addr, val);
-			} else {
-				/* protected mode */
-				cpu_lmemorywrite(addr, val);
+	if (!(sd->flag & CPU_DESC_FLAG_WRITABLE)) {
+		cpu_memorywrite_check(sd, offset, 1,
+		    (idx == CPU_SS_INDEX) ? SS_EXCEPTION : GP_EXCEPTION);
+	} else {
+		switch (sd->type) {
+		case 6: case 7:
+			if (offset <= sd->u.seg.limit) {
+				if (idx == CPU_SS_INDEX)
+					exc = SS_EXCEPTION;
+				else
+					exc = GP_EXCEPTION;
+				goto err;
+			}
+			break;
+
+		default:
+			if (offset > sd->u.seg.limit) {
+				if (idx == CPU_SS_INDEX)
+					exc = SS_EXCEPTION;
+				else
+					exc = GP_EXCEPTION;
+				goto err;
 			}
-			return;
+			break;
 		}
-		cpu_memorywrite_check(sd, madr, 1,
-		    (idx == CPU_SS_INDEX) ? SS_EXCEPTION : GP_EXCEPTION);
 	}
-	/*NOTREACHED*/
+	addr = CPU_STAT_SREGBASE(idx) + offset;
+	if (!CPU_STAT_PM) {
+		/* real mode */
+		cpu_memorywrite(addr, val);
+	} else {
+		/* protected mode */
+		cpu_lmemorywrite(addr, val, CPU_STAT_USER_MODE);
+	}
+	return;
+
+err:
+	EXCEPTION(exc, 0);
 }
 
 void MEMCALL
-cpu_vmemorywrite_w(int idx, DWORD madr, WORD val)
+cpu_vmemorywrite_w(int idx, UINT32 offset, UINT16 val)
 {
 	descriptor_t *sd;
-	DWORD addr;
+	UINT32 addr;
+	int exc;
 
 	__ASSERT((unsigned int)idx < CPU_SEGREG_NUM);
 
 	sd = &CPU_STAT_SREG(idx);
 	if (!sd->valid) {
-		EXCEPTION(GP_EXCEPTION, 0);
+		exc = GP_EXCEPTION;
+		goto err;
 	}
 
-	if (!CPU_INST_AS32)
-		madr &= 0xffff;
-	for (;;) {
-		if ((sd->flag & CPU_DESC_WRITABLE)
-		    || (madr <= sd->u.seg.segend - 1)) {
-			addr = CPU_STAT_SREGBASE(idx) + madr;
-			if (!CPU_STAT_PM) {
-				/* real mode */
-				cpu_memorywrite_w(addr, val);
-			} else {
-				/* protected mode */
-				cpu_lmemorywrite_w(addr, val);
+	if (!(sd->flag & CPU_DESC_FLAG_WRITABLE)) {
+		cpu_memorywrite_check(sd, offset, 2,
+		    (idx == CPU_SS_INDEX) ? SS_EXCEPTION : GP_EXCEPTION);
+	} else {
+		switch (sd->type) {
+		case 6: case 7:
+			if (offset - 1 <= sd->u.seg.limit) {
+				if (idx == CPU_SS_INDEX)
+					exc = SS_EXCEPTION;
+				else
+					exc = GP_EXCEPTION;
+				goto err;
+			}
+			break;
+
+		default:
+			if (offset > sd->u.seg.limit - 1) {
+				if (idx == CPU_SS_INDEX)
+					exc = SS_EXCEPTION;
+				else
+					exc = GP_EXCEPTION;
+				goto err;
 			}
-			return;
+			break;
 		}
-		cpu_memorywrite_check(sd, madr, 2,
-		    (idx == CPU_SS_INDEX) ? SS_EXCEPTION : GP_EXCEPTION);
 	}
-	/*NOTREACHED*/
+	addr = CPU_STAT_SREGBASE(idx) + offset;
+	if (!CPU_STAT_PM) {
+		/* real mode */
+		cpu_memorywrite_w(addr, val);
+	} else {
+		/* protected mode */
+		cpu_lmemorywrite_w(addr, val, CPU_STAT_USER_MODE);
+	}
+	return;
+
+err:
+	EXCEPTION(exc, 0);
 }
 
 void MEMCALL
-cpu_vmemorywrite_d(int idx, DWORD madr, DWORD val)
+cpu_vmemorywrite_d(int idx, UINT32 offset, UINT32 val)
 {
 	descriptor_t *sd;
-	DWORD addr;
+	UINT32 addr;
+	int exc;
 
 	__ASSERT((unsigned int)idx < CPU_SEGREG_NUM);
 
 	sd = &CPU_STAT_SREG(idx);
 	if (!sd->valid) {
-		EXCEPTION(GP_EXCEPTION, 0);
+		exc = GP_EXCEPTION;
+		goto err;
 	}
 
-	if (!CPU_INST_AS32)
-		madr &= 0xffff;
-	for (;;) {
-		if ((sd->flag & CPU_DESC_WRITABLE)
-		    || (madr <= sd->u.seg.segend - 3)) {
-			addr = CPU_STAT_SREGBASE(idx) + madr;
-			if (!CPU_STAT_PM) {
-				/* real mode */
-				cpu_memorywrite_d(addr, val);
-			} else {
-				/* protected mode */
-				cpu_lmemorywrite_d(addr, val);
-			}
-			return;
-		}
-		cpu_memorywrite_check(sd, madr, 4,
+	if (!(sd->flag & CPU_DESC_FLAG_WRITABLE)) {
+		cpu_memorywrite_check(sd, offset, 4,
 		    (idx == CPU_SS_INDEX) ? SS_EXCEPTION : GP_EXCEPTION);
-	}
-	/*NOTREACHED*/
-}
-
-/*
- * physical address memory function
- */
-void MEMCALL
-cpu_memorywrite_d(DWORD address, DWORD value)
-{
-	DWORD adr = address & CPU_STAT_ADRSMASK;
-
-	if (adr < LOWMEM - 3) {
-		__i286_memorywrite_d(adr, value);
-	} else if (adr < LOWMEM) {
-		cpu_memorywrite_w(adr, value & 0xffff);
-		cpu_memorywrite_w(adr + 2, (value >> 16) & 0xffff);
-	} else {
-		adr -= LOWMEM;
-		if (adr < extmem_size - 3) {
-			STOREINTELDWORD(cpumem + adr, value);
-		} else if (adr < extmem_size) {
-			cpu_memorywrite_w(adr, value & 0xffff);
-			cpu_memorywrite_w(adr + 2, (value >> 16) & 0xffff);
-		}
-	}
-}
-
-void MEMCALL
-cpu_memorywrite_w(DWORD address, WORD value)
-{
-	DWORD adr = address & CPU_STAT_ADRSMASK;
-
-	if (adr < LOWMEM - 1) {
-		__i286_memorywrite_w(adr, value);
-	} else if (adr < LOWMEM) {
-		__i286_memorywrite(adr, value & 0xff);
-		cpumem[adr - (LOWMEM - 1)] = (value >> 8) & 0xff;
-	} else {
-		adr -= LOWMEM;
-		if (adr < extmem_size - 1) {
-			STOREINTELWORD(cpumem + adr, value);
-		} else if (adr == extmem_size - 1) {
-			cpumem[adr] = value & 0xff;
-		}
-	}
-}
-
-void MEMCALL
-cpu_memorywrite(DWORD address, BYTE value)
-{
-	DWORD adr = address & CPU_STAT_ADRSMASK;
-
-	if (adr < LOWMEM) {
-		__i286_memorywrite(adr, value);
 	} else {
-		adr -= LOWMEM;
-		if (adr < extmem_size) {
-			cpumem[adr] = value;
-		}
-	}
-}
-
-DWORD MEMCALL
-cpu_memoryread_d(DWORD address)
-{
-	DWORD adr = address & CPU_STAT_ADRSMASK;
-	DWORD val;
+		switch (sd->type) {
+		case 6: case 7:
+			if (offset - 3 <= sd->u.seg.limit) {
+				if (idx == CPU_SS_INDEX)
+					exc = SS_EXCEPTION;
+				else
+					exc = GP_EXCEPTION;
+				goto err;
+			}
+			break;
 
-	if (adr < LOWMEM - 3) {
-		val = __i286_memoryread_d(adr);
-	} else if (adr < LOWMEM) {
-		val = cpu_memoryread_w(adr);
-		val |= (DWORD)cpu_memoryread_w(adr + 2) << 16;
-	} else {
-		adr -= LOWMEM;
-		if (adr < extmem_size - 3) {
-			val = LOADINTELDWORD(cpumem + adr);
-		} else {
-			val = cpu_memoryread_w(adr);
-			val |= (DWORD)cpu_memoryread_w(adr + 2) << 16;
+		default:
+			if (offset > sd->u.seg.limit - 3) {
+				if (idx == CPU_SS_INDEX)
+					exc = SS_EXCEPTION;
+				else
+					exc = GP_EXCEPTION;
+				goto err;
+			}
+			break;
 		}
 	}
-	return val;
-}
-
-WORD MEMCALL
-cpu_memoryread_w(DWORD address)
-{
-	DWORD adr = address & CPU_STAT_ADRSMASK;
-	WORD val;
-
-	if (adr < LOWMEM - 1) {
-		val = __i286_memoryread_w(adr);
-	} else if (adr < LOWMEM) {
-		val = cpu_memoryread(adr);
-		val |= (WORD)cpumem[adr - (LOWMEM - 1)] << 8;
+	addr = CPU_STAT_SREGBASE(idx) + offset;
+	if (!CPU_STAT_PM) {
+		/* real mode */
+		cpu_memorywrite_d(addr, val);
 	} else {
-		adr -= LOWMEM;
-		if (adr < extmem_size - 1) {
-			val = LOADINTELWORD(cpumem + adr);
-		} else if (adr == extmem_size - 1) {
-			val = 0xff00 | cpumem[adr];
-		} else {
-			val = (WORD)-1;
-		}
+		/* protected mode */
+		cpu_lmemorywrite_d(addr, val, CPU_STAT_USER_MODE);
 	}
-	return val;
-}
+	return;
 
-BYTE MEMCALL
-cpu_memoryread(DWORD address)
-{
-	DWORD adr = address & CPU_STAT_ADRSMASK;
-	BYTE val;
-
-	if (adr < LOWMEM) {
-		val = __i286_memoryread(adr);
-	} else {
-		adr -= LOWMEM;
-		if (adr < extmem_size) {
-			val = cpumem[adr];
-		} else {
-			val = (BYTE)-1;
-		}
-	}
-	return val;
+err:
+	EXCEPTION(exc, 0);
 }