[WiiU] Exception handler: fix coreinit handles, add opcode to DSIs

Coreinit seems to get special handles, so adding a special case should
make its relative addresses actually become helpful again. Let's just
hope __PPCExit stays at 0x180!
Also added the violating opcode to the DSI message; may have to move it
in case it pushes stuff off the end of the screen.

Untested at time of commit. Hopefully this should make debugging libretro#5357 a
bit easier...

wiiu/system/exception_handler.c

@@ -90,9 +90,8 @@ void __attribute__((__noreturn__)) exception_cb(OSContext* ctx, OSExceptionType
 
 /*	First up, the pretty header that tells you wtf just happened */
 	if (type == OS_EXCEPTION_TYPE_DSI) {
-	/*	Exception type and offending instruction location
-		Also initializes exception_msgbuf, use buf_add from now on */
-		buf_add("DSI: Instr at %08" PRIX32, ctx->srr0);
+	/*	Exception type and offending instruction location + opcode */
+		buf_add("DSI: Instr at %08" PRIX32 " (%08 " PRIX32 ")", ctx->srr0, *(unsigned int*)(ctx->srr0));
 	/*	Was this a read or a write? */
 		if (ctx->dsisr & DSISR_WRITE_ATTEMPTED) {
 			buf_add(" bad write to");
@@ -216,6 +215,12 @@ void exception_print_symbol(uint32_t addr) {
 		/*	Try for a base address */
 			void* libAddr;
 			OSDynLoad_Acquire(symbolName, &libAddr);
+		/*	Special case for coreinit; which has broken handles */
+			if (strcmp(symbolName, "coreinit.rpl")) {
+				void* PPCExit_addr;
+				OSDynLoad_FindExport(libAddr, 0, "__PPCExit", &PPCExit_addr);
+				libAddr = PPCExit_addr - 0x180;
+			}
 			*seperator = '|';
 		/*	We got one! */
 			if (libAddr) {