--- np2/i386c/ia32/cpu_mem.c	2004/01/27 15:54:45	1.8
+++ np2/i386c/ia32/cpu_mem.c	2012/01/08 18:49:31	1.32
@@ -1,7 +1,5 @@
-/*	$Id: cpu_mem.c,v 1.8 2004/01/27 15:54:45 monaka Exp $	*/
-
 /*
- * Copyright (c) 2002-2003 NONAKA Kimihiro
+ * Copyright (c) 2002-2004 NONAKA Kimihiro
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -12,8 +10,6 @@
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
- * 3. The name of the author may not be used to endorse or promote products
- *    derived from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
@@ -31,931 +27,609 @@
 #include "cpu.h"
 #include "memory.h"
 
-#define	cpumem		i386core.e.ext
-#define	extmem_size	i386core.e.extsize
-
 
 /*
- * initialize 1MB-16MB memory
+ * memory access check
  */
-
-int
-init_cpumem(UINT8 usemem)
-{
-	UINT32	size;
-
-	size = usemem << 20;
-	if (size >= (LOWMEM - 0x100000)) {
-		size -= (LOWMEM - 0x100000);
-	}
-	else {
-		size = 0;
-	}
-	if (extmem_size != size) {
-		if (cpumem) {
-			free(cpumem);
-			cpumem = 0;
+static int MEMCALL check_limit_upstairs(descriptor_t *sdp, UINT32 offset, UINT len);
+static void MEMCALL cpu_memoryread_check(descriptor_t *sdp, UINT32 offset, UINT len, int e);
+static void MEMCALL cpu_memorywrite_check(descriptor_t *sdp, UINT32 offset, UINT len, int e);
+
+static int MEMCALL
+check_limit_upstairs(descriptor_t *sdp, UINT32 offset, UINT len)
+{
+	UINT32 limit;
+	UINT32 end;
+
+	__ASSERT(sdp != NULL);
+	__ASSERT(len > 0);
+
+	len--;
+	end = offset + len;
+	limit = SEG_IS_32BIT(sdp) ? 0xffffffff : 0x0000ffff;
+
+	if (SEG_IS_DATA(sdp) && SEG_IS_EXPANDDOWN_DATA(sdp)) {
+		/* expand-down data segment */
+		if (sdp->u.seg.limit == 0) {
+			/*
+			 *   32bit       16bit
+			 * +-------+   +-------+ FFFFFFFFh
+			 * |       |   |       |
+			 * |       |   +  [1]  + 0000FFFFh
+			 * | valid |   |       |
+			 * |       |   +-------+ 0000FFFFh - len -1
+			 * |       |   | valid |
+			 * +-------+   +-------+ 00000000h
+			 */
+			if (!SEG_IS_32BIT(sdp)) {
+				if ((len > limit)		/* len check */
+				 || (end > limit)) {		/* [1] */
+					goto exc;
+				}
+			} else {
+				sdp->flag |= CPU_DESC_FLAG_WHOLEADR;
+			}
+		} else {
+			/*
+			 *   32bit       16bit
+			 * +-------+   +-------+ FFFFFFFFh
+			 * |  [2]  |   |       |
+			 * +-------+   +.......+ FFFFFFFFh - len - 1
+			 * |       |   |  [2]  |
+			 * |       |   +.......+ 0000FFFFh
+			 * | valid |   |       |
+			 * |       |   +-------+ 0000FFFFh - len - 1
+			 * |       |   | valid |
+			 * +-------+   +-------+ seg.limit
+			 * |  [1]  |   |  [1]  |
+			 * +-------+   +-------+ 00000000h
+			 */
+			if ((len > limit - sdp->u.seg.limit)	/* len check */
+			 || (end < offset)			/* wrap check */
+			 || (offset < sdp->u.seg.limit) 	/* [1] */
+			 || (end > limit)) {			/* [2] */
+				goto exc;
+			}
 		}
-		if (size) {
-			cpumem = (BYTE *)malloc(size);
-			if (cpumem == NULL) {
-				size = 0;
+	} else {
+		/* expand-up data or code segment */
+		if (sdp->u.seg.limit == limit) {
+			/*
+			 *   32bit       16bit
+			 * +-------+   +-------+ FFFFFFFFh
+			 * |       |   |       |
+			 * |       |   +  [1]  + 0000FFFFh
+			 * | valid |   |       |
+			 * |       |   +-------+ 0000FFFFh - len - 1
+			 * |       |   | valid |
+			 * +-------+   +-------+ 00000000h
+			 */
+			if (!SEG_IS_32BIT(sdp)) {
+				if ((len > limit)		/* len check */
+				 || (offset + len > limit)) {	/* [1] */
+					goto exc;
+				}
+			} else {
+				sdp->flag |= CPU_DESC_FLAG_WHOLEADR;
+			}
+		} else {
+			/*
+			 *   32bit       16bit
+			 * +-------+   +-------+ FFFFFFFFh
+			 * |       |   |       |
+			 * |       |   +.......+ 0000FFFFh
+			 * |  [1]  |   |  [1]  |
+			 * +.......+   +.......+ seg.limit
+			 * |       |   |       |
+			 * +-------+   +-------+ seg.limit - len - 1
+			 * | valid |   | valid |
+			 * +-------+   +-------+ 00000000h
+			 */
+			if ((len > sdp->u.seg.limit)		/* len check */
+			 || (end < offset)			/* wrap check */
+			 || (end > sdp->u.seg.limit + 1)) {	/* [1] */
+				goto exc;
 			}
 		}
-		extmem_size = size;
 	}
-	return SUCCESS;
+	return 1;	/* Ok! */
+
+exc:
+	VERBOSE(("check_limit_upstairs: check failure: offset = 0x%08x, len = %d", offset, len + 1));
+#if defined(DEBUG)
+	segdesc_dump(sdp);
+#endif
+	return 0;
 }
 
-
-/*
- * memory access check
- */
-void
-cpu_memoryread_check(descriptor_t* sd, DWORD offset, DWORD length, int e)
+static void MEMCALL
+cpu_memoryread_check(descriptor_t *sdp, UINT32 offset, UINT len, int e)
 {
-	DWORD uplimit;
 
-	if (CPU_STAT_PM) {
-		/* invalid */
-		if (!sd->valid) {
-			VERBOSE(("cpu_memoryread_check: invalid"));
-			EXCEPTION(GP_EXCEPTION, 0);
-		}
+	__ASSERT(sdp != NULL);
+	__ASSERT(len > 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 (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);
-			}
-			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;
+	if (!SEG_IS_VALID(sdp)) {
+		e = GP_EXCEPTION;
+		goto exc;
+	}
+	if (!SEG_IS_PRESENT(sdp)
+	 || SEG_IS_SYSTEM(sdp)
+	 || (SEG_IS_CODE(sdp) && !SEG_IS_READABLE_CODE(sdp))) {
+		goto exc;
+	}
 
-		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);
-			}
-			if (uplimit - offset < length - 1) {
-				VERBOSE(("cpu_memoryread_check: uplimit(%08x) - offset(%08x) < length(%08x) - 1", uplimit, offset, length));
-				EXCEPTION(e, 0);
-			}
-			break;
+	switch (sdp->type) {
+	case 0:	 case 1:	/* ro */
+	case 2:  case 3:	/* rw */
+	case 4:  case 5:	/* ro (expand down) */
+	case 6:  case 7:	/* rw (expand down) */
+	case 10: case 11:	/* rx */
+	case 14: case 15:	/* rxc */
+		if (!check_limit_upstairs(sdp, offset, len))
+			goto exc;
+		break;
 
-		default:
-			VERBOSE(("cpu_memoryread_check: invalid type (type = %d)", sd->type));
-			EXCEPTION(e, 0);
-			break;
-		}
+	default:
+		goto exc;
 	}
-	sd->flag |= CPU_DESC_FLAG_READABLE;
+	sdp->flag |= CPU_DESC_FLAG_READABLE;
+	return;
+
+exc:
+	VERBOSE(("cpu_memoryread_check: check failure: offset = 0x%08x, len = %d", offset, len));
+#if defined(DEBUG)
+	segdesc_dump(sdp);
+#endif
+	EXCEPTION(e, 0);
 }
 
-void
-cpu_memorywrite_check(descriptor_t* sd, DWORD offset, DWORD length, int e)
+static void MEMCALL
+cpu_memorywrite_check(descriptor_t *sdp, UINT32 offset, UINT len, int e)
 {
-	DWORD uplimit;
 
-	if (CPU_STAT_PM) {
-		/* invalid */
-		if (!sd->valid) {
-			VERBOSE(("cpu_memorywrite_check: invalid"));
-			EXCEPTION(GP_EXCEPTION, 0);
-		}
+	__ASSERT(sdp != NULL);
+	__ASSERT(len > 0);
 
-		/* not present */
-		if (!sd->p) {
-			VERBOSE(("cpu_memorywrite_check: not present"));
-			EXCEPTION(e, 0);
-		}
-
-		if (!sd->s) {
-			VERBOSE(("cpu_memorywrite_check: system segment"));
-			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);
-			}
-			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;
+	if (!SEG_IS_VALID(sdp)) {
+		e = GP_EXCEPTION;
+		goto exc;
+	}
+	if (!SEG_IS_PRESENT(sdp)
+	 || SEG_IS_SYSTEM(sdp)
+	 || SEG_IS_CODE(sdp)
+	 || (SEG_IS_DATA(sdp) && !SEG_IS_WRITABLE_DATA(sdp))) {
+		goto exc;
+	}
 
-		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);
-			}
-			if (uplimit - offset < length - 1) {
-				VERBOSE(("cpu_memorywrite_check: uplimit(%08x) - offset(%08x) < length(%08x) - 1", uplimit, offset, length));
-				EXCEPTION(e, 0);
-			}
-			break;
+	switch (sdp->type) {
+	case 2: case 3:	/* rw */
+	case 6: case 7:	/* rw (expand down) */
+		if (!check_limit_upstairs(sdp, offset, len))
+			goto exc;
+		break;
 
-		default:
-			VERBOSE(("cpu_memorywrite_check: invalid type (type = %d)", sd->type));
-			EXCEPTION(e, 0);
-			break;
-		}
+	default:
+		goto exc;
 	}
-	sd->flag |= CPU_DESC_FLAG_WRITABLE;
+	sdp->flag |= CPU_DESC_FLAG_WRITABLE | CPU_DESC_FLAG_READABLE;
+	return;
+
+exc:
+	VERBOSE(("cpu_memorywrite_check: check failure: offset = 0x%08x, len = %d", offset, len));
+#if defined(DEBUG)
+	segdesc_dump(sdp);
+#endif
+	EXCEPTION(e, 0);
 }
 
-BOOL
-cpu_stack_push_check(descriptor_t* sdp, DWORD esp, DWORD length)
+void MEMCALL
+cpu_stack_push_check(UINT16 s, descriptor_t *sdp, UINT32 sp, UINT len)
 {
-	DWORD limit;
+	UINT32 limit;
+	UINT32 start;
 
-	if (!CPU_STAT_PM)
-		return TRUE;
+	__ASSERT(sdp != NULL);
+	__ASSERT(len > 0);
 
-	if (!sdp->valid || !sdp->p)
-		return FALSE;
-	if (!sdp->s || sdp->u.seg.c || !sdp->u.seg.wr)
-		return FALSE;
-
-	if (!sdp->d) {
-		esp &= 0xffff;
-		limit = 0xffff;
-	} else {
-		limit = 0xffffffff;
+	len--;
+
+	if (!SEG_IS_VALID(sdp)
+	 || !SEG_IS_PRESENT(sdp)
+	 || SEG_IS_SYSTEM(sdp)
+	 || SEG_IS_CODE(sdp)
+	 || !SEG_IS_WRITABLE_DATA(sdp)) {
+		goto exc;
 	}
-	if (sdp->u.seg.ec) {
+
+	start = sp - len;
+	limit = SEG_IS_32BIT(sdp) ? 0xffffffff : 0x0000ffff;
+
+	if (SEG_IS_EXPANDDOWN_DATA(sdp)) {
 		/* expand-down stack */
-		if ((esp == 0)
-		 || (esp < length)
-		 || (esp - length <= sdp->u.seg.limit)
-		 || (esp > limit))
-			return FALSE;
+		if (!SEG_IS_32BIT(sdp)) {
+			if (sp > limit) {			/* [*] */
+				goto exc;
+			}
+		}
+		if (sdp->u.seg.limit == 0) {
+			/*
+			 *   32bit       16bit
+			 * +-------+   +-------+ FFFFFFFFh
+			 * |       |   |  [*]  |
+			 * |       |   +-------+ 0000FFFFh
+			 * | valid |   |       |
+			 * |       |   | valid |
+			 * |       |   |       |
+			 * +-------+   +-------+ 00000000h
+			 */
+			if (!SEG_IS_32BIT(sdp)) {
+				if (sp > limit) {		/* [1] */
+					goto exc;
+				}
+			} else {
+				sdp->flag |= CPU_DESC_FLAG_WHOLEADR;
+			}
+		} else {
+			/*
+			 *   32bit       16bit
+			 * +-------+   +-------+ FFFFFFFFh
+			 * |       |   |  [*]  |
+			 * | valid |   +-------+ 0000FFFFh
+			 * |       |   | valid |
+			 * +-------+   +-------+ seg.limit + len - 1
+			 * |       |   |       |
+			 * +..[1]..+   +..[1]..+ seg.limit
+			 * |       |   |       |
+			 * +-------+   +-------+ 00000000h
+			 */
+			if ((len > limit - sdp->u.seg.limit)	/* len check */
+			 || (start > sp)			/* wrap check */
+			 || (start < sdp->u.seg.limit)) {	/* [1] */
+				goto exc;
+			}
+		}
 	} 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 (sdp->u.seg.limit == limit) {
+			/*
+			 *   32bit       16bit
+			 * +-------+   +-------+ FFFFFFFFh
+			 * |       |   |  [1]  |
+			 * |       |   +-------+ 0000FFFFh
+			 * | valid |   |       |
+			 * |       |   | valid |
+			 * |       |   |       |
+			 * +-------+   +-------+ 00000000h
+			 */
+			if (!SEG_IS_32BIT(sdp)) {
+				if (sp > limit) {		/* [1] */
+					goto exc;
+				}
+			} else {
+				sdp->flag |= CPU_DESC_FLAG_WHOLEADR;
+			}
 		} else {
-			if ((esp < length)
-			 || (esp - 1 > sdp->u.seg.limit))
-				return FALSE;
+			/*
+			 *   32bit       16bit
+			 * +-------+   +-------+ FFFFFFFFh
+			 * |       |   |       |
+			 * |  [1]  |   +  [1]  + 0000FFFFh
+			 * |       |   |       |
+			 * +-------+   +-------+ seg.limit
+			 * | valid |   | valid |
+			 * +.......+   +.......+ len - 1
+			 * |  [+]  |   |  [+]  |
+			 * +-------+   +-------+ 00000000h
+			 *
+			 * [+]: wrap check
+			 */
+			if ((len > sdp->u.seg.limit)		/* len check */
+			 || (start > sp)			/* wrap check */
+			 || (sp > sdp->u.seg.limit + 1)) {	/* [1] */
+				goto exc;
+			}
 		}
 	}
-	return TRUE;
+	return;
+
+exc:
+	VERBOSE(("cpu_stack_push_check: check failure: selector = 0x%04x, sp = 0x%08x, len = %d", s, sp, len));
+#if defined(DEBUG)
+	segdesc_dump(sdp);
+#endif
+	EXCEPTION(SS_EXCEPTION, s & 0xfffc);
 }
 
-BOOL
-cpu_stack_pop_check(descriptor_t* sdp, DWORD esp, DWORD length)
+void MEMCALL
+cpu_stack_pop_check(UINT16 s, descriptor_t *sdp, UINT32 sp, UINT len)
 {
-	DWORD limit;
 
-	if (!CPU_STAT_PM)
-		return TRUE;
+	__ASSERT(sdp != NULL);
+	__ASSERT(len > 0);
 
-	if (!sdp->valid || !sdp->p)
-		return FALSE;
-	if (!sdp->s || sdp->u.seg.c || !sdp->u.seg.wr)
-		return FALSE;
-
-	if (!sdp->d) {
-		esp &= 0xffff;
-		limit = 0xffff;
-	} else {
-		limit = 0xffffffff;
-	}
-	if (sdp->u.seg.ec) {
-		/* expand-down stack */
-		if ((esp == limit)
-		 || ((limit - esp) + 1 < length))
-			return FALSE;
-	} else {
-		/* expand-up stack */
-		if ((esp == limit)
-		 || (sdp->u.seg.segend == 0)
-		 || (esp > sdp->u.seg.limit)
-		 || ((sdp->u.seg.limit - esp) + 1 < length))
-			return FALSE;
+	if (!SEG_IS_VALID(sdp)
+	 || !SEG_IS_PRESENT(sdp)
+	 || SEG_IS_SYSTEM(sdp)
+	 || SEG_IS_CODE(sdp)
+	 || !SEG_IS_WRITABLE_DATA(sdp)) {
+		goto exc;
 	}
-	return TRUE;
-}
-
 
-#undef	OVERRUN_CHECK
+	if (!check_limit_upstairs(sdp, sp, len))
+		goto exc;
+	return;
 
-#if defined(OVERRUN_CHECK)
-#define	OVERRUN_EXCEPTION()	EXCEPTION(GP_EXCEPTION, 0)
-#else
-#define	OVERRUN_EXCEPTION()
+exc:
+	VERBOSE(("cpu_stack_pop_check: check failure: selector = 0x%04x, sp = 0x%08x, len = %d", s, sp, len));
+#if defined(DEBUG)
+	segdesc_dump(sdp);
 #endif
+	EXCEPTION(SS_EXCEPTION, s & 0xfffc);
+}
+
 
 /*
  * code fetch
  */
-BYTE MEMCALL
-cpu_codefetch(DWORD offset)
+UINT8 MEMCALL
+cpu_codefetch(UINT32 offset)
 {
-	descriptor_t *sd;
-	DWORD addr;
+	const int ucrw = CPU_PAGE_READ_CODE | CPU_STAT_USER_MODE;
+	descriptor_t *sdp;
+	UINT32 addr;
+
+	sdp = &CPU_CS_DESC;
+	addr = sdp->u.seg.segbase + offset;
+
+	if (!CPU_STAT_PM)
+		return cpu_memoryread(addr);
+	if (offset <= sdp->u.seg.limit)
+		return cpu_lmemoryread(addr, ucrw);
 
-	sd = &CPU_STAT_SREG(CPU_CS_INDEX);
-	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);
-	}
 	EXCEPTION(GP_EXCEPTION, 0);
 	return 0;	/* compiler happy */
 }
 
-WORD MEMCALL
-cpu_codefetch_w(DWORD offset)
+UINT16 MEMCALL
+cpu_codefetch_w(UINT32 offset)
 {
-	descriptor_t *sd;
-	DWORD addr;
+	const int ucrw = CPU_PAGE_READ_CODE | CPU_STAT_USER_MODE;
+	descriptor_t *sdp;
+	UINT32 addr;
+
+	sdp = &CPU_CS_DESC;
+	addr = sdp->u.seg.segbase + offset;
+
+	if (!CPU_STAT_PM)
+		return cpu_memoryread_w(addr);
+	if (offset <= sdp->u.seg.limit - 1)
+		return cpu_lmemoryread_w(addr, ucrw);
 
-	sd = &CPU_STAT_SREG(CPU_CS_INDEX);
-	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);
-	}
 	EXCEPTION(GP_EXCEPTION, 0);
 	return 0;	/* compiler happy */
 }
 
-DWORD MEMCALL
-cpu_codefetch_d(DWORD offset)
+UINT32 MEMCALL
+cpu_codefetch_d(UINT32 offset)
 {
-	descriptor_t *sd;
-	DWORD addr;
+	const int ucrw = CPU_PAGE_READ_CODE | CPU_STAT_USER_MODE;
+	descriptor_t *sdp;
+	UINT32 addr;
+
+	sdp = &CPU_CS_DESC;
+	addr = sdp->u.seg.segbase + offset;
+
+	if (!CPU_STAT_PM)
+		return cpu_memoryread_d(addr);
+
+	if (offset <= sdp->u.seg.limit - 3)
+		return cpu_lmemoryread_d(addr, ucrw);
 
-	sd = &CPU_STAT_SREG(CPU_CS_INDEX);
-	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);
-	}
 	EXCEPTION(GP_EXCEPTION, 0);
 	return 0;	/* compiler happy */
 }
 
-
 /*
- * virtual address -> linear address
+ * additional physical address memory access functions
  */
-BYTE MEMCALL
-cpu_vmemoryread(int idx, DWORD offset)
+UINT64 MEMCALL
+cpu_memoryread_q(UINT32 paddr)
 {
-	descriptor_t *sd;
-	DWORD addr;
-	int exc;
+	UINT64 value;
 
-	__ASSERT((unsigned int)idx < CPU_SEGREG_NUM);
+	value = cpu_memoryread_d(paddr);
+	value += (UINT64)cpu_memoryread_d(paddr + 4) << 32;
 
-	sd = &CPU_STAT_SREG(idx);
-	if (!sd->valid) {
-		exc = GP_EXCEPTION;
-		goto err;
-	}
-
-	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;
+	return value;
+}
 
-		default:
-			if (offset > sd->u.seg.limit) {
-				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(addr);
-	return cpu_lmemoryread(addr);
+void MEMCALL
+cpu_memorywrite_q(UINT32 paddr, UINT64 value)
+{
 
-err:
-	EXCEPTION(exc, 0);
-	return 0;	/* compiler happy */
+	cpu_memorywrite_d(paddr, (UINT32)value);
+	cpu_memorywrite_d(paddr + 4, (UINT32)(value >> 32));
 }
 
-WORD MEMCALL
-cpu_vmemoryread_w(int idx, DWORD offset)
+REG80 MEMCALL
+cpu_memoryread_f(UINT32 paddr)
 {
-	descriptor_t *sd;
-	DWORD addr;
-	int exc;
+	REG80 value;
+	int i;
 
-	__ASSERT((unsigned int)idx < CPU_SEGREG_NUM);
+	for (i = 0; i < (int)sizeof(REG80); ++i) {
+		value.b[i] = cpu_memoryread(paddr + i);
+	}
+	return value;
+}
 
-	sd = &CPU_STAT_SREG(idx);
-	if (!sd->valid) {
-		exc = GP_EXCEPTION;
-		goto err;
+void MEMCALL
+cpu_memorywrite_f(UINT32 paddr, const REG80 *value)
+{
+	int i;
+
+	for (i = 0; i < (int)sizeof(REG80); ++i) {
+		cpu_memorywrite(paddr + i, value->b[i]);
 	}
+}
 
-	if (!(sd->flag & CPU_DESC_FLAG_READABLE)) {
-		cpu_memoryread_check(sd, offset, 2,
-		    (idx == CPU_SS_INDEX) ? SS_EXCEPTION : GP_EXCEPTION);
-	} 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;
+/*
+ * virtual address memory access functions
+ */
+#define	CHOOSE_EXCEPTION(sreg) \
+	(((sreg) == CPU_SS_INDEX) ? SS_EXCEPTION : GP_EXCEPTION)
 
-		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);
+#include "cpu_mem.mcr"
 
-err:
-	EXCEPTION(exc, 0);
-	return 0;	/* compiler happy */
-}
+VIRTUAL_ADDRESS_MEMORY_ACCESS_FUNCTION(b, UINT8, 1)
+VIRTUAL_ADDRESS_MEMORY_ACCESS_FUNCTION(w, UINT16, 2)
+VIRTUAL_ADDRESS_MEMORY_ACCESS_FUNCTION(d, UINT32, 4)
 
-DWORD MEMCALL
-cpu_vmemoryread_d(int idx, DWORD offset)
+UINT64 MEMCALL
+cpu_vmemoryread_q(int idx, UINT32 offset)
 {
-	descriptor_t *sd;
-	DWORD addr;
+	descriptor_t *sdp;
+	UINT32 addr;
 	int exc;
 
 	__ASSERT((unsigned int)idx < CPU_SEGREG_NUM);
 
-	sd = &CPU_STAT_SREG(idx);
-	if (!sd->valid) {
-		exc = GP_EXCEPTION;
-		goto err;
-	}
+	sdp = &CPU_STAT_SREG(idx);
+	addr = sdp->u.seg.segbase + offset;
 
-	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;
+	if (!CPU_STAT_PM)
+		return cpu_memoryread_q(addr);
 
-		default:
-			if (offset > sd->u.seg.limit - 3) {
-				if (idx == CPU_SS_INDEX)
-					exc = SS_EXCEPTION;
-				else
-					exc = GP_EXCEPTION;
-				goto err;
-			}
-			break;
-		}
+	if (!SEG_IS_VALID(sdp)) {
+		exc = GP_EXCEPTION;
+		goto err;
 	}
-	addr = CPU_STAT_SREGBASE(idx) + offset;
-	if (!CPU_STAT_PM)
-		return cpu_memoryread_d(addr);
-	return cpu_lmemoryread_d(addr);
+	if (!(sdp->flag & CPU_DESC_FLAG_READABLE)) {
+		cpu_memoryread_check(sdp, offset, 8, CHOOSE_EXCEPTION(idx));
+	} else if (!(sdp->flag & CPU_DESC_FLAG_WHOLEADR)) {
+		if (!check_limit_upstairs(sdp, offset, 8))
+			goto range_failure;
+	} 
+	return cpu_lmemoryread_q(addr, CPU_PAGE_READ_DATA | CPU_STAT_USER_MODE);
 
+range_failure:
+	VERBOSE(("cpu_vmemoryread_q: type = %d, offset = %08x, limit = %08x", sdp->type, offset, sdp->u.seg.limit));
+	exc = CHOOSE_EXCEPTION(idx);
 err:
 	EXCEPTION(exc, 0);
 	return 0;	/* compiler happy */
 }
 
-/* vaddr memory write */
 void MEMCALL
-cpu_vmemorywrite(int idx, DWORD offset, BYTE val)
+cpu_vmemorywrite_q(int idx, UINT32 offset, UINT64 value)
 {
-	descriptor_t *sd;
-	DWORD addr;
+	descriptor_t *sdp;
+	UINT32 addr;
 	int exc;
 
 	__ASSERT((unsigned int)idx < CPU_SEGREG_NUM);
 
-	sd = &CPU_STAT_SREG(idx);
-	if (!sd->valid) {
-		exc = GP_EXCEPTION;
-		goto err;
-	}
+	sdp = &CPU_STAT_SREG(idx);
+	addr = sdp->u.seg.segbase + offset;
 
-	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;
-			}
-			break;
-		}
-	}
-	addr = CPU_STAT_SREGBASE(idx) + offset;
 	if (!CPU_STAT_PM) {
-		/* real mode */
-		cpu_memorywrite(addr, val);
-	} else {
-		/* protected mode */
-		cpu_lmemorywrite(addr, val);
+		cpu_memorywrite_q(addr, value);
+		return;
 	}
-	return;
-
-err:
-	EXCEPTION(exc, 0);
-}
 
-void MEMCALL
-cpu_vmemorywrite_w(int idx, DWORD offset, WORD val)
-{
-	descriptor_t *sd;
-	DWORD addr;
-	int exc;
-
-	__ASSERT((unsigned int)idx < CPU_SEGREG_NUM);
-
-	sd = &CPU_STAT_SREG(idx);
-	if (!sd->valid) {
+	if (!SEG_IS_VALID(sdp)) {
 		exc = GP_EXCEPTION;
 		goto err;
 	}
-
-	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;
-			}
-			break;
-		}
-	}
-	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);
+	if (!(sdp->flag & CPU_DESC_FLAG_WRITABLE)) {
+		cpu_memorywrite_check(sdp, offset, 8, CHOOSE_EXCEPTION(idx));
+	} else if (!(sdp->flag & CPU_DESC_FLAG_WHOLEADR)) {
+		if (!check_limit_upstairs(sdp, offset, 8))
+			goto range_failure;
 	}
+	cpu_lmemorywrite_q(addr, value, CPU_PAGE_WRITE_DATA | CPU_STAT_USER_MODE);
 	return;
 
+range_failure:
+	VERBOSE(("cpu_vmemorywrite_q: type = %d, offset = %08x, limit = %08x", sdp->type, offset, sdp->u.seg.limit));
+	exc = CHOOSE_EXCEPTION(idx);
 err:
 	EXCEPTION(exc, 0);
 }
 
-void MEMCALL
-cpu_vmemorywrite_d(int idx, DWORD offset, DWORD val)
+REG80 MEMCALL
+cpu_vmemoryread_f(int idx, UINT32 offset)
 {
-	descriptor_t *sd;
-	DWORD addr;
+	descriptor_t *sdp;
+	UINT32 addr;
 	int exc;
 
 	__ASSERT((unsigned int)idx < CPU_SEGREG_NUM);
 
-	sd = &CPU_STAT_SREG(idx);
-	if (!sd->valid) {
-		exc = GP_EXCEPTION;
-		goto err;
-	}
+	sdp = &CPU_STAT_SREG(idx);
+	addr = sdp->u.seg.segbase + offset;
 
-	if (!(sd->flag & CPU_DESC_FLAG_WRITABLE)) {
-		cpu_memorywrite_check(sd, offset, 4,
-		    (idx == CPU_SS_INDEX) ? SS_EXCEPTION : GP_EXCEPTION);
-	} else {
-		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 (!CPU_STAT_PM)
+		return cpu_memoryread_f(addr);
 
-		default:
-			if (offset > sd->u.seg.limit - 3) {
-				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) {
-		/* real mode */
-		cpu_memorywrite_d(addr, val);
-	} else {
-		/* protected mode */
-		cpu_lmemorywrite_d(addr, val);
+	if (!SEG_IS_VALID(sdp)) {
+		exc = GP_EXCEPTION;
+		goto err;
 	}
-	return;
+	if (!(sdp->flag & CPU_DESC_FLAG_READABLE)) {
+		cpu_memoryread_check(sdp, offset, 10, CHOOSE_EXCEPTION(idx));
+	} else if (!(sdp->flag & CPU_DESC_FLAG_WHOLEADR)) {
+		if (!check_limit_upstairs(sdp, offset, 10))
+			goto range_failure;
+	} 
+	return cpu_lmemoryread_f(addr, CPU_PAGE_READ_DATA | CPU_STAT_USER_MODE);
 
+range_failure:
+	VERBOSE(("cpu_vmemoryread_f: type = %d, offset = %08x, limit = %08x", sdp->type, offset, sdp->u.seg.limit));
+	exc = CHOOSE_EXCEPTION(idx);
 err:
 	EXCEPTION(exc, 0);
-}
-
-/*
- * physical address memory function
- */
-void MEMCALL
-cpu_memorywrite_d(DWORD address, DWORD value)
-{
-	DWORD adr = address & CPU_STAT_ADRSMASK;
-	DWORD diff;
-	DWORD off;
-
-	if (adr < LOWMEM - 3) {
-		__i286_memorywrite_d(adr, value);
-	} else if (adr < LOWMEM) {
-		diff = LOWMEM - adr;
-
-		switch (diff) {
-		default:
-			ia32_panic("cpu_memorywrite_d: diff(%d)", diff);
-			break;
-
-		case 3:
-			__i286_memorywrite_w(adr, value & 0xffff);
-			value >>= 16;
-			__i286_memorywrite(adr + 2, value & 0xff);
-			value >>= 8;
-			break;
-
-		case 2:
-			__i286_memorywrite_w(adr, value & 0xffff);
-			value >>= 16;
-			break;
-
-		case 1:
-			__i286_memorywrite(adr, value & 0xff);
-			value >>= 8;
-			break;
-		}
-
-		if (extmem_size > 0) {
-			off = 0;
-
-			switch (4 - diff) {
-			case 3:
-				cpumem[off++] = value & 0xff;
-				if (off >= extmem_size) {
-					OVERRUN_EXCEPTION();
-					break;
-				}
-				value >>= 8;
-				/*FALLTHROUGH*/
-			case 2:
-				cpumem[off++] = value & 0xff;
-				if (off >= extmem_size) {
-					OVERRUN_EXCEPTION();
-					break;
-				}
-				value >>= 8;
-				/*FALLTHROUGH*/
-			case 1:
-				cpumem[off] = value & 0xff;
-				break;
-			}
-		} else {
-			OVERRUN_EXCEPTION();
-		}
-	} else if (extmem_size > 0) {
-		adr -= LOWMEM;
-		if (adr < extmem_size - 3) {
-			STOREINTELDWORD(cpumem + adr, value);
-		} else if (adr < extmem_size) {
-			diff = extmem_size - adr;
-
-			switch (diff) {
-			default:
-				ia32_panic("cpu_memorywrite_d: diff(%d)", diff);
-				break;
-
-			case 3:
-				cpumem[adr] = value & 0xff;
-				value >>= 8;
-				adr++;
-				/*FALLTHROUGH*/
-			case 2:
-				cpumem[adr] = value & 0xff;
-				value >>= 8;
-				adr++;
-				/*FALLTHROUGH*/
-			case 1:
-				cpumem[adr] = value & 0xff;
-				break;
-			}
-			OVERRUN_EXCEPTION();
-		} else {
-			OVERRUN_EXCEPTION();
-		}
-	} else {
-		OVERRUN_EXCEPTION();
+	{
+		REG80 dummy;
+		memset(&dummy, 0, sizeof(dummy));
+		return dummy;	/* compiler happy */
 	}
 }
 
 void MEMCALL
-cpu_memorywrite_w(DWORD address, WORD value)
+cpu_vmemorywrite_f(int idx, UINT32 offset, const REG80 *value)
 {
-	DWORD adr = address & CPU_STAT_ADRSMASK;
+	descriptor_t *sdp;
+	UINT32 addr;
+	int exc;
 
-	if (adr < LOWMEM - 1) {
-		__i286_memorywrite_w(adr, value);
-	} else if (adr < LOWMEM) {
-		__i286_memorywrite(adr, value & 0xff);
-		if (extmem_size > 0) {
-			cpumem[0] = (value >> 8) & 0xff;
-		} else {
-			OVERRUN_EXCEPTION();
-		}
-	} else if (extmem_size > 0) {
-		adr -= LOWMEM;
-		if (adr < extmem_size - 1) {
-			STOREINTELWORD(cpumem + adr, value);
-		} else if (adr == extmem_size - 1) {
-			cpumem[adr] = value & 0xff;
-			OVERRUN_EXCEPTION();
-		} else {
-			OVERRUN_EXCEPTION();
-		}
-	} else {
-		OVERRUN_EXCEPTION();
-	}
-}
+	__ASSERT((unsigned int)idx < CPU_SEGREG_NUM);
 
-void MEMCALL
-cpu_memorywrite(DWORD address, BYTE value)
-{
-	DWORD adr = address & CPU_STAT_ADRSMASK;
+	sdp = &CPU_STAT_SREG(idx);
+	addr = sdp->u.seg.segbase + offset;
 
-	if (adr < LOWMEM) {
-		__i286_memorywrite(adr, value);
-	} else if (extmem_size > 0) {
-		adr -= LOWMEM;
-		if (adr < extmem_size) {
-			cpumem[adr] = value;
-		} else {
-			OVERRUN_EXCEPTION();
-		}
-	} else {
-		OVERRUN_EXCEPTION();
+	if (!CPU_STAT_PM) {
+		cpu_memorywrite_f(addr, value);
+		return;
 	}
-}
 
-DWORD MEMCALL
-cpu_memoryread_d(DWORD address)
-{
-	DWORD adr = address & CPU_STAT_ADRSMASK;
-	DWORD val;
-	DWORD diff;
-	int shift;
-
-	if (adr < LOWMEM - 3) {
-		val = __i286_memoryread_d(adr);
-	} else if (adr < LOWMEM) {
-		diff = LOWMEM - adr;
-
-		switch (diff) {
-		default:
-			ia32_panic("cpu_memoryread_d: diff(%d)", diff);
-			val = 0;	/* compiler happy */
-			break;
-
-		case 3:
-			val = __i286_memoryread_w(adr);
-			val |= (DWORD)__i286_memoryread(adr + 2) << 16;
-			if (extmem_size > 0) {
-				val |= (DWORD)cpumem[0] << 24;
-			} else {
-				val |= 0xff000000;
-				OVERRUN_EXCEPTION();
-			}
-			break;
-
-		case 2:
-			val = __i286_memoryread_w(adr);
-			if (extmem_size > 1) {
-				val |= ((DWORD)LOADINTELWORD(cpumem)) << 16;
-			} else if (extmem_size > 0) {
-				val |= 0xff000000 | ((DWORD)cpumem[0] << 16);
-				OVERRUN_EXCEPTION();
-			} else {
-				val |= 0xffff0000;
-				OVERRUN_EXCEPTION();
-			}
-			break;
-
-		case 1:
-			val = __i286_memoryread(adr);
-			if (extmem_size > 2) {
-				val |= (DWORD)LOADINTELWORD(cpumem) << 8;
-				val |= (DWORD)cpumem[2] << 24;
-			} else if (extmem_size > 1) {
-				val |= ((DWORD)LOADINTELWORD(cpumem)) << 8;
-				val |= 0xff000000;
-				OVERRUN_EXCEPTION();
-			} else if (extmem_size > 0) {
-				val |= 0xffff0000 | ((DWORD)cpumem[0] << 8);
-				OVERRUN_EXCEPTION();
-			} else {
-				val |= 0xffffff00;
-				OVERRUN_EXCEPTION();
-			}
-			break;
-		}
-	} else if (extmem_size > 0) {
-		adr -= LOWMEM;
-		if (adr < extmem_size - 3) {
-			val = LOADINTELDWORD(cpumem + adr);
-		} else if (adr < extmem_size) {
-			diff = extmem_size - adr;
-			val = 0;
-			shift = 0;
-
-			switch (diff) {
-			default:
-				ia32_panic("cpu_memoryread_d: diff(%d)", diff);
-				break;
-
-			case 3:
-				val |= (DWORD)cpumem[adr];
-				shift += 8;
-				adr++;
-				/*FALLTHROUGH*/
-			case 2:
-				val |= (DWORD)cpumem[adr] << shift;
-				shift += 8;
-				adr++;
-				/*FALLTHROUGH*/
-			case 1:
-				val |= (DWORD)cpumem[adr] << shift;
-				shift += 8;
-				break;
-			}
-			val |= ((DWORD)-1) << shift;
-			OVERRUN_EXCEPTION();
-		} else {
-			val = (DWORD)-1;
-			OVERRUN_EXCEPTION();
-		}
-	} else {
-		val = (DWORD)-1;
-		OVERRUN_EXCEPTION();
+	if (!SEG_IS_VALID(sdp)) {
+		exc = GP_EXCEPTION;
+		goto err;
 	}
-	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 = __i286_memoryread(adr);
-		if (extmem_size > 0) {
-			val |= (WORD)cpumem[0] << 8;
-		} else {
-			val |= 0xff00;
-			OVERRUN_EXCEPTION();
-		}
-	} else if (extmem_size > 0) {
-		adr -= LOWMEM;
-		if (adr < extmem_size - 1) {
-			val = LOADINTELWORD(cpumem + adr);
-		} else if (adr == extmem_size - 1) {
-			val = 0xff00 | cpumem[adr];
-			OVERRUN_EXCEPTION();
-		} else {
-			val = (WORD)-1;
-			OVERRUN_EXCEPTION();
-		}
-	} else {
-		val = (WORD)-1;
-		OVERRUN_EXCEPTION();
+	if (!(sdp->flag & CPU_DESC_FLAG_WRITABLE)) {
+		cpu_memorywrite_check(sdp, offset, 10, CHOOSE_EXCEPTION(idx));
+	} else if (!(sdp->flag & CPU_DESC_FLAG_WHOLEADR)) {
+		if (!check_limit_upstairs(sdp, offset, 10))
+			goto range_failure;
 	}
-	return val;
-}
-
-BYTE MEMCALL
-cpu_memoryread(DWORD address)
-{
-	DWORD adr = address & CPU_STAT_ADRSMASK;
-	BYTE val;
+	cpu_lmemorywrite_f(addr, value, CPU_PAGE_WRITE_DATA | CPU_STAT_USER_MODE);
+	return;
 
-	if (adr < LOWMEM) {
-		val = __i286_memoryread(adr);
-	} else if (extmem_size > 0) {
-		adr -= LOWMEM;
-		if (adr < extmem_size) {
-			val = cpumem[adr];
-		} else {
-			val = (BYTE)-1;
-			OVERRUN_EXCEPTION();
-		}
-	} else {
-		val = (BYTE)-1;
-		OVERRUN_EXCEPTION();
-	}
-	return val;
+range_failure:
+	VERBOSE(("cpu_vmemorywrite_f: type = %d, offset = %08x, limit = %08x", sdp->type, offset, sdp->u.seg.limit));
+	exc = CHOOSE_EXCEPTION(idx);
+err:
+	EXCEPTION(exc, 0);
 }