Added a document that lists some CodeGen differences.
Added a document that lists some CodeGen differences.

There is a number of known changes in the binaries produced for the same source code when compared to equivalent output of the old compiler. Some changes are improvements, some are bug fixes and some are indirect result of differences in implementation and emit strategies.

Most of the actual form and shape of emitted code is not a contract and compiler is only responsible for efficiently conveying the semantics of the original source. However there is enough interest in intentional changes here and it seems to be useful to have one place where some of the more significant changes are listed.

EricArndt/roslyn,rchande/roslyn,CaptainHayashi/roslyn,dpoeschl/roslyn,stephentoub/roslyn,oberxon/roslyn,ericfe-ms/roslyn,weltkante/roslyn,jrharmon/roslyn,tvand7093/roslyn,AmadeusW/roslyn,taylorjonl/roslyn,mseamari/Stuff,Shiney/roslyn,yjfxfjch/roslyn,amcasey/roslyn,TyOverby/roslyn,MichalStrehovsky/roslyn,KamalRathnayake/roslyn,REALTOBIZ/roslyn,EricArndt/roslyn,MattWindsor91/roslyn,yjfxfjch/roslyn,mavasani/roslyn,mseamari/Stuff,KevinH-MS/roslyn,KamalRathnayake/roslyn,Maxwe11/roslyn,pjmagee/roslyn,jcouv/roslyn,paulvanbrenk/roslyn,enginekit/roslyn,AArnott/roslyn,evilc0des/roslyn,a-ctor/roslyn,vslsnap/roslyn,ahmedshuhel/roslyn,jamesqo/roslyn,tmeschter/roslyn,dovzhikova/roslyn,leppie/roslyn,sharadagrawal/Roslyn,tsdl2013/roslyn,MatthieuMEZIL/roslyn,Giftednewt/roslyn,nguerrera/roslyn,mmitche/roslyn,AnthonyDGreen/roslyn,natidea/roslyn,AlekseyTs/roslyn,amcasey/roslyn,michalhosala/roslyn,natidea/roslyn,3F/roslyn,jroggeman/roslyn,danielcweber/roslyn,drognanar/roslyn,VitalyTVA/roslyn,HellBrick/roslyn,moozzyk/roslyn,dovzhikova/roslyn,Pvlerick/roslyn,VShangxiao/roslyn,SeriaWei/roslyn,pdelvo/roslyn,jcouv/roslyn,budcribar/roslyn,akrisiun/roslyn,AdamSpeight2008/roslyn-AdamSpeight2008,jeffanders/roslyn,jonatassaraiva/roslyn,ErikSchierboom/roslyn,RipCurrent/roslyn,jkotas/roslyn,akrisiun/roslyn,Shiney/roslyn,CyrusNajmabadi/roslyn,xoofx/roslyn,ValentinRueda/roslyn,JakeGinnivan/roslyn,stebet/roslyn,natgla/roslyn,3F/roslyn,bartdesmet/roslyn,YOTOV-LIMITED/roslyn,xasx/roslyn,grianggrai/roslyn,evilc0des/roslyn,eriawan/roslyn,magicbing/roslyn,davkean/roslyn,aanshibudhiraja/Roslyn,Giftednewt/roslyn,EricArndt/roslyn,a-ctor/roslyn,GuilhermeSa/roslyn,cston/roslyn,OmarTawfik/roslyn,Giten2004/roslyn,tang7526/roslyn,balajikris/roslyn,agocke/roslyn,kienct89/roslyn,jhendrixMSFT/roslyn,srivatsn/roslyn,AlexisArce/roslyn,MichalStrehovsky/roslyn,bartdesmet/roslyn,jroggeman/roslyn,oocx/roslyn,rchande/roslyn,jeremymeng/roslyn,sharadagrawal/Roslyn,swaroop-sridhar/roslyn,JakeGinnivan/roslyn,managed-commons/roslyn,cston/roslyn,dotnet/roslyn,krishnarajbb/roslyn,FICTURE7/roslyn,budcribar/roslyn,poizan42/roslyn,vslsnap/roslyn,KevinH-MS/roslyn,physhi/roslyn,VSadov/roslyn,ValentinRueda/roslyn,tsdl2013/roslyn,weltkante/roslyn,tvand7093/roslyn,bartdesmet/roslyn,devharis/roslyn,magicbing/roslyn,jmarolf/roslyn,Pvlerick/roslyn,kelltrick/roslyn,AlexisArce/roslyn,MatthieuMEZIL/roslyn,mavasani/roslyn,oberxon/roslyn,magicbing/roslyn,pjmagee/roslyn,pdelvo/roslyn,vcsjones/roslyn,sharadagrawal/TestProject2,akrisiun/roslyn,diryboy/roslyn,KiloBravoLima/roslyn,GuilhermeSa/roslyn,v-codeel/roslyn,Inverness/roslyn,shyamnamboodiripad/roslyn,krishnarajbb/roslyn,drognanar/roslyn,grianggrai/roslyn,RipCurrent/roslyn,aelij/roslyn,poizan42/roslyn,tmat/roslyn,bkoelman/roslyn,shyamnamboodiripad/roslyn,khellang/roslyn,jhendrixMSFT/roslyn,natgla/roslyn,stephentoub/roslyn,orthoxerox/roslyn,FICTURE7/roslyn,kelltrick/roslyn,Giten2004/roslyn,wvdd007/roslyn,moozzyk/roslyn,KiloBravoLima/roslyn,russpowers/roslyn,KevinH-MS/roslyn,jeremymeng/roslyn,sharwell/roslyn,michalhosala/roslyn,mattscheffer/roslyn,balajikris/roslyn,CaptainHayashi/roslyn,nagyistoce/roslyn,jonatassaraiva/roslyn,tmeschter/roslyn,srivatsn/roslyn,danielcweber/roslyn,dotnet/roslyn,AlekseyTs/roslyn,wvdd007/roslyn,chenxizhang/roslyn,stebet/roslyn,BugraC/roslyn,devharis/roslyn,jamesqo/roslyn,agocke/roslyn,jroggeman/roslyn,MichalStrehovsky/roslyn,jasonmalinowski/roslyn,abock/roslyn,michalhosala/roslyn,jaredpar/roslyn,JakeGinnivan/roslyn,AdamSpeight2008/roslyn-AdamSpeight2008,VPashkov/roslyn,MattWindsor91/roslyn,robinsedlaczek/roslyn,mseamari/Stuff,jaredpar/roslyn,kelltrick/roslyn,xoofx/roslyn,gafter/roslyn,thomaslevesque/roslyn,hanu412/roslyn,VShangxiao/roslyn,swaroop-sridhar/roslyn,ilyes14/roslyn,3F/roslyn,tannergooding/roslyn,gafter/roslyn,tang7526/roslyn,mattwar/roslyn,khyperia/roslyn,mgoertz-msft/roslyn,panopticoncentral/roslyn,HellBrick/roslyn,jaredpar/roslyn,nemec/roslyn,jonatassaraiva/roslyn,CyrusNajmabadi/roslyn,AmadeusW/roslyn,mattwar/roslyn,v-codeel/roslyn,lorcanmooney/roslyn,genlu/roslyn,xoofx/roslyn,heejaechang/roslyn,Maxwe11/roslyn,AmadeusW/roslyn,Hosch250/roslyn,jkotas/roslyn,heejaechang/roslyn,BugraC/roslyn,KevinRansom/roslyn,antonssonj/roslyn,supriyantomaftuh/roslyn,paulvanbrenk/roslyn,AlexisArce/roslyn,abock/roslyn,REALTOBIZ/roslyn,vslsnap/roslyn,BugraC/roslyn,KashishArora/Roslyn,tannergooding/roslyn,tmat/roslyn,drognanar/roslyn,Inverness/roslyn,xasx/roslyn,ahmedshuhel/roslyn,ValentinRueda/roslyn,YOTOV-LIMITED/roslyn,hanu412/roslyn,REALTOBIZ/roslyn,KirillOsenkov/roslyn,krishnarajbb/roslyn,brettfo/roslyn,reaction1989/roslyn,jeffanders/roslyn,nagyistoce/roslyn,paulvanbrenk/roslyn,antonssonj/roslyn,ericfe-ms/roslyn,robinsedlaczek/roslyn,khyperia/roslyn,stephentoub/roslyn,antiufo/roslyn,KamalRathnayake/roslyn,tmat/roslyn,OmarTawfik/roslyn,OmniSharp/roslyn,Inverness/roslyn,chenxizhang/roslyn,diryboy/roslyn,ljw1004/roslyn,MattWindsor91/roslyn,VitalyTVA/roslyn,Pvlerick/roslyn,jamesqo/roslyn,mattscheffer/roslyn,amcasey/roslyn,tmeschter/roslyn,devharis/roslyn,physhi/roslyn,thomaslevesque/roslyn,Hosch250/roslyn,KirillOsenkov/roslyn,doconnell565/roslyn,diryboy/roslyn,ErikSchierboom/roslyn,genlu/roslyn,oberxon/roslyn,OmniSharp/roslyn,kuhlenh/roslyn,thomaslevesque/roslyn,VPashkov/roslyn,jmarolf/roslyn,ilyes14/roslyn,vcsjones/roslyn,gafter/roslyn,poizan42/roslyn,bbarry/roslyn,eriawan/roslyn,nemec/roslyn,SeriaWei/roslyn,bbarry/roslyn,tannergooding/roslyn,brettfo/roslyn,genlu/roslyn,VitalyTVA/roslyn,VSadov/roslyn,grianggrai/roslyn,panopticoncentral/roslyn,jhendrixMSFT/roslyn,AdamSpeight2008/roslyn-AdamSpeight2008,vcsjones/roslyn,xasx/roslyn,SeriaWei/roslyn,antiufo/roslyn,basoundr/roslyn,MihaMarkic/roslyn-prank,russpowers/roslyn,natgla/roslyn,hanu412/roslyn,evilc0des/roslyn,rgani/roslyn,bbarry/roslyn,abock/roslyn,reaction1989/roslyn,lorcanmooney/roslyn,VPashkov/roslyn,AnthonyDGreen/roslyn,huoxudong125/roslyn,panopticoncentral/roslyn,AnthonyDGreen/roslyn,VShangxiao/roslyn,jbhensley/roslyn,zmaruo/roslyn,ErikSchierboom/roslyn,tang7526/roslyn,wvdd007/roslyn,KirillOsenkov/roslyn,natidea/roslyn,YOTOV-LIMITED/roslyn,shyamnamboodiripad/roslyn,tsdl2013/roslyn,mattwar/roslyn,davkean/roslyn,a-ctor/roslyn,Maxwe11/roslyn,russpowers/roslyn,eriawan/roslyn,sharadagrawal/Roslyn,zmaruo/roslyn,basoundr/roslyn,MattWindsor91/roslyn,jrharmon/roslyn,jbhensley/roslyn,zooba/roslyn,kienct89/roslyn,aanshibudhiraja/Roslyn,KashishArora/Roslyn,aelij/roslyn,mmitche/roslyn,cston/roslyn,Shiney/roslyn,oocx/roslyn,dpoeschl/roslyn,CaptainHayashi/roslyn,lisong521/roslyn,khellang/roslyn,AArnott/roslyn,zmaruo/roslyn,mirhagk/roslyn,MatthieuMEZIL/roslyn,v-codeel/roslyn,dovzhikova/roslyn,budcribar/roslyn,yeaicc/roslyn,jbhensley/roslyn,RipCurrent/roslyn,yjfxfjch/roslyn,supriyantomaftuh/roslyn,AlekseyTs/roslyn,managed-commons/roslyn,stebet/roslyn,jeffanders/roslyn,sharwell/roslyn,yeaicc/roslyn,zooba/roslyn,oocx/roslyn,lisong521/roslyn,rchande/roslyn,danielcweber/roslyn,nemec/roslyn,ilyes14/roslyn,OmniSharp/roslyn,physhi/roslyn,mgoertz-msft/roslyn,jrharmon/roslyn,zooba/roslyn,jasonmalinowski/roslyn,nagyistoce/roslyn,chenxizhang/roslyn,robinsedlaczek/roslyn,bkoelman/roslyn,srivatsn/roslyn,sharadagrawal/TestProject2,MihaMarkic/roslyn-prank,CyrusNajmabadi/roslyn,DustinCampbell/roslyn,nguerrera/roslyn,TyOverby/roslyn,lisong521/roslyn,moozzyk/roslyn,doconnell565/roslyn,jkotas/roslyn,enginekit/roslyn,MihaMarkic/roslyn-prank,jasonmalinowski/roslyn,DustinCampbell/roslyn,ericfe-ms/roslyn,doconnell565/roslyn,pdelvo/roslyn,supriyantomaftuh/roslyn,KevinRansom/roslyn,jcouv/roslyn,mgoertz-msft/roslyn,jmarolf/roslyn,HellBrick/roslyn,weltkante/roslyn,kuhlenh/roslyn,droyad/roslyn,KashishArora/Roslyn,leppie/roslyn,Hosch250/roslyn,reaction1989/roslyn,droyad/roslyn,AArnott/roslyn,davkean/roslyn,mmitche/roslyn,taylorjonl/roslyn,sharadagrawal/TestProject2,khellang/roslyn,KevinRansom/roslyn,pjmagee/roslyn,leppie/roslyn,yeaicc/roslyn,dotnet/roslyn,mattscheffer/roslyn,balajikris/roslyn,kuhlenh/roslyn,aanshibudhiraja/Roslyn,dpoeschl/roslyn,taylorjonl/roslyn,rgani/roslyn,sharwell/roslyn,ljw1004/roslyn,heejaechang/roslyn,bkoelman/roslyn,huoxudong125/roslyn,TyOverby/roslyn,jeremymeng/roslyn,FICTURE7/roslyn,nguerrera/roslyn,ahmedshuhel/roslyn,enginekit/roslyn,huoxudong125/roslyn,basoundr/roslyn,swaroop-sridhar/roslyn,mirhagk/roslyn,Giten2004/roslyn,Giftednewt/roslyn,aelij/roslyn,managed-commons/roslyn,tvand7093/roslyn,droyad/roslyn,kienct89/roslyn,VSadov/roslyn,antiufo/roslyn,rgani/roslyn,GuilhermeSa/roslyn,DustinCampbell/roslyn,antonssonj/roslyn,agocke/roslyn,orthoxerox/roslyn,khyperia/roslyn,lorcanmooney/roslyn,mavasani/roslyn,OmarTawfik/roslyn,ljw1004/roslyn,orthoxerox/roslyn,mirhagk/roslyn,KiloBravoLima/roslyn,brettfo/roslyn