simx86: enable W^X layout

Update cpatch to resolve the fault address.

Just that simple now?? Thanks Bart!

Author: stsp

src/base/emu-i386/simx86/codebuf.c

@@ -39,7 +39,7 @@ void InitGenCodeBuf(void)
 {
     void *addr;
 
-#if HAVE_DECL_MREMAP_MAYMOVE && 0
+#if HAVE_DECL_MREMAP_MAYMOVE
     int err;
 
     addr = mmap(NULL, CODEBUF_SZ, PROT_NONE,

src/base/emu-i386/simx86/cpatch.c

@@ -606,15 +606,15 @@ int Cpatch(sigcontext_t *scp)
 #if PROFILE
     CpatchTotal++;
 #endif
-    p = eip;
+    p = GetGenCodeBuf(eip);
     if ((*p==0xf2 || *p==0xf3) && (p[1] == 0x66 || p[2] == 0x90) &&
 	p[3] == 0x90 && p[4] == 0x90) {
 	unsigned char op;
 
 	// rep movs, rep stos, rep lods, rep scas, rep cmps
 	// we have a sequence:	f2/f3 op 90 90 90
 	//		or	f2/f3 66 op 90 90 (f2 for cmps/scas only)
-	if (debug_level('e')>1) e_printf("### REP patch at %p\n",eip);
+	if (debug_level('e')>1) e_printf("### REP patch at %p\n",p);
 	op = p[1];
 	/* as all ops are between 0xa4 and 0xaf we can encode override
 	   prefix as 0x10 and repne as 0x40 */
@@ -659,14 +659,14 @@ int Cpatch(sigcontext_t *scp)
     }
     if (v==0x2f0488) {		// movb %%al,(%%edi,%%ebp,1)
 	// we have a sequence:	88 04 2f
-	if (debug_level('e')>1) e_printf("### Byte write patch at %p\n",eip);
+	if (debug_level('e')>1) e_printf("### Byte write patch at %p\n",p);
 	JSRPATCH(p,Ofs_stub_wri_8);
 	return 1;
     }
     if (v==0x2f0489) {		// mov %%{e}ax,(%%edi,%%ebp,1)
 	// we have a sequence:	89 04 2f
 	//		or	66 89 04 2f
-	if (debug_level('e')>1) e_printf("### Word/Long write patch at %p\n",eip);
+	if (debug_level('e')>1) e_printf("### Word/Long write patch at %p\n",p);
 	if (w16) {
 	    p[-1] = 0x90; JSRPATCH(p,Ofs_stub_wri_16);;
 	}
@@ -677,14 +677,14 @@ int Cpatch(sigcontext_t *scp)
     }
     if (v==0x2f048a) {		// movb (%%edi,%%ebp,1),%%al
 	// we have a sequence:	8a 04 2f 90 90 90
-	if (debug_level('e')>1) e_printf("### Byte read patch at %p\n",eip);
+	if (debug_level('e')>1) e_printf("### Byte read patch at %p\n",p);
 	JSRPATCH(p,Ofs_stub_read_8);
 	return 1;
     }
     if (v==0x2f048b) {		// mov (%%edi,%%ebp,1),%%{e}ax
 	// we have a sequence:	8b 04 2f
 	//		or	66 8b 04 2f
-	if (debug_level('e')>1) e_printf("### Word/Long read patch at %p\n",eip);
+	if (debug_level('e')>1) e_printf("### Word/Long read patch at %p\n",p);
 	if (w16) {
 	    p[-1] = 0x90; JSRPATCH(p,Ofs_stub_read_16);
 	}
@@ -700,12 +700,12 @@ int Cpatch(sigcontext_t *scp)
 int UnCpatch(unsigned char *eip)
 {
     unsigned char *p;
-    p = eip;
+    p = GetGenCodeBuf(eip);
 
-    if (*eip != 0xff) return 1;
+    if (*p != 0xff) return 1;
     if (debug_level('e')) {
-	e_printf("UnCpatch   at %p was %02x%02x%02x%02x%02x\n",eip,
-	    eip[0],eip[1],eip[2],eip[3],eip[4]);
+	e_printf("UnCpatch   at %p was %02x%02x%02x%02x%02x\n",p,
+	    p[0],p[1],p[2],p[3],p[4]);
     }
 #if PROFILE
     UncpatchTotal++;
@@ -742,8 +742,8 @@ int UnCpatch(unsigned char *eip)
     }
     else return 1;
     if (debug_level('e')) {
-	e_printf("UnCpatched at %p  is %02x%02x%02x%02x%02x\n",eip,
-	    eip[0],eip[1],eip[2],eip[3],eip[4]);
+	e_printf("UnCpatched at %p  is %02x%02x%02x%02x%02x\n",p,
+	    p[0],p[1],p[2],p[3],p[4]);
     }
     return 0;
 }