From d7c4d7afbf0472d2b842e352bdf066c2dbe9ff98 Mon Sep 17 00:00:00 2001
From: gbeauche <>
Date: Mon, 20 May 2002 18:12:01 +0000
Subject: [PATCH] Backout "ignoresegv" support on FreeBSD/x86 for now.
 Unfortunately, the configure script would hang whereas standalone testing
 will pass all tests. Any idea why?? - Unix/sigsegv.cpp
 (ix86_skip_instruction): Add decoder for mozbl instruction.  
 (SIGSEGV_REGISTER_FILE [FreeBSD/x86]): Note why we start at EDI offset  
 rather than plain sigcontext pointer. i.e. I don't know sigset_t size  
 beforehand and don't intend to.

---
 BasiliskII/ChangeLog            |  3 +--
 BasiliskII/README               |  2 +-
 BasiliskII/src/Unix/sigsegv.cpp | 10 ++++++++--
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/BasiliskII/ChangeLog b/BasiliskII/ChangeLog
index 52a57605..ce98ae76 100644
--- a/BasiliskII/ChangeLog
+++ b/BasiliskII/ChangeLog
@@ -3,8 +3,7 @@ V1.0 (snapshot) - <date>
    just 60Hz (e.g. moving the mouse made the caret blink faster)
  - Unix: cleaned up pthread attributes [Brian Johnson]
  - Unix: fixed floppy problems under Linux
- - Unix: implement "ignoresegv" feature on Linux/x86, Linux/ppc, Darwin/ppc,
-   FreeBSD/x86
+ - Unix: implement "ignoresegv" feature on Linux/x86, Linux/ppc, Darwin/ppc
 
 V1.0 (snapshot) - 15.Jan.2002
  - added support for on-the-fly video resolution and depth switching, and
diff --git a/BasiliskII/README b/BasiliskII/README
index c79c35fc..e8e0cb03 100644
--- a/BasiliskII/README
+++ b/BasiliskII/README
@@ -578,7 +578,7 @@ Unix:
 
     Set this to "true" to ignore illegal memory accesses. The default
     is "false". This feature is only implemented on the following
-    platforms: Linux/x86, Linux/ppc, Darwin/ppc, FreeBSD/x86.
+    platforms: Linux/x86, Linux/ppc, Darwin/ppc.
 
 AmigaOS:
 
diff --git a/BasiliskII/src/Unix/sigsegv.cpp b/BasiliskII/src/Unix/sigsegv.cpp
index 6b8d42f4..42bbbe1d 100644
--- a/BasiliskII/src/Unix/sigsegv.cpp
+++ b/BasiliskII/src/Unix/sigsegv.cpp
@@ -217,8 +217,11 @@ static void powerpc_decode_instruction(instruction_t *instruction, unsigned int
 #define SIGSEGV_FAULT_ADDRESS			sip->si_addr
 #if (defined(i386) || defined(__i386__))
 #define SIGSEGV_FAULT_INSTRUCTION		(((struct sigcontext *)scp)->sc_eip)
-#define SIGSEGV_REGISTER_FILE			((unsigned int *)&(((struct sigcontext *)scp)->sc_edi))
+#define SIGSEGV_REGISTER_FILE			((unsigned int *)&(((struct sigcontext *)scp)->sc_edi)) /* EDI is the first GPR (even below EIP) in sigcontext */
+/* (gb) Disable because this would hang configure script for some reason
+ * though standalone testing gets it right. Any idea why?
 #define SIGSEGV_SKIP_INSTRUCTION		ix86_skip_instruction
+*/
 #endif
 #if defined(__linux__)
 #if (defined(i386) || defined(__i386__))
@@ -463,7 +466,9 @@ static bool ix86_skip_instruction(unsigned int * regs)
 	// Decode instruction
 	switch (eip[0]) {
 	case 0x0f:
-	    if (eip[1] == 0xb7) { // MOVZX r32, r/m16
+	    switch (eip[1]) {
+	    case 0xb6: // MOVZX r32, r/m8
+	    case 0xb7: // MOVZX r32, r/m16
 		switch (eip[2] & 0xc0) {
 		case 0x80:
 		    reg = (eip[2] >> 3) & 7;
@@ -479,6 +484,7 @@ static bool ix86_skip_instruction(unsigned int * regs)
 		    break;
 		}
 		len += 3 + ix86_step_over_modrm(eip + 2);
+		break;
 	    }
 	  break;
 	case 0x8a: // MOV r8, r/m8