I think I know what the problem is.
My hackintosh has got a i7-4790 cpu and a cpu builtin graphic HD4600.
After upgraded to High Sierra, iTunes crashed often.
Then I noticed this post, and I've tried some configuration of shiki, include remove shiki completely, but nothing changed.
After that, i followed the post about patch ssdt menthioned in post #213, iTunes stopped from crashing.
But, I found, quick sync was disabled.
Then I re-enabled shiki, quick sync enabled too, crashing of iTunes came back too.
I thought, I may find some way to enable quick sync without shiki. Finally, I found some thing in the info.plist of AppleGVA.framework. The renderer was set to be offline for some type of mac.
The following code shows the config for iMac 14.2
Code:
141 <key>Mac-27ADBB7B4CEE8E61</key>
142 <dict>
143 <key>facetimeDecode</key>
144 <true/>
145 <key>forceBoostOff</key>
146 <true/>
147 <key>forceOfflineRenderer</key>
148 <true/>
149 <key>hwe</key>
150 <true/>
151 <key>hweBGRA</key>
152 <true/>
153 <key>ke1</key>
154 <true/>
155 <key>pp</key>
156 <true/>
157 </dict>
hmmm, I changed my smbios in clover to some other type to match the configure in order to enable quick sync, and the quick sync was enabled finally.
Then, the crashing of iTunes came back.
So, maybe, Apple has written some specific code for it's own hardware. We cannot enable quick sync simply by force enable something.