cmd/compile/internal/gc: clean up errcmp
cmd/compile/internal/gc: clean up errcmp

Change-Id: Id07811a25bf4aa3ff834e7254a3dfb04522b2926
Reviewed-on: https://go-review.googlesource.com/14174
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>
Run-TryBot: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Dave Cheney <bfcdf3e6ca6cef45543bfbb57509c92aec9a39fb@cheney.net>

akutz/go,linux-on-ibm-z/go,theass/go,ericsnowcurrently/go,jdhenke/go,miolini/go,CAFxX/go,deft-code/go,suncycheng/go,zhangg/go,devpadawan/go,jonasi/go,skatsuta/go,beealone/go,xiuzhifu/go,mikekap/go,cloudflare/go,vanloswang/go,alex-zhang/go,CAFxX/go,jdhenke/go,xiuzhifu/go,4ad/go,likesea/go,fjballest/golang,fjballest/golang,dpatel06/go,codestation/go,roth1002/go,theif519/go,joshsammut/go,jonasi/go,rachtsingh/gogojuice,Samurais/go,fjballest/golang,binarycrusader/go,golang/go,myPublicGit/go,mwhudson/go,dterei/go,samanalysis/go,NunoEdgarGub1/go,CarterTsai/go,alex-zhang/go,Samurais/go,josharian/go,ifagnosticism/go,derekmarcotte/go,beealone/go,beealone/go,gdey/go,theass/go,skatsuta/go,ifagnosticism/go,CarterTsai/go,CAFxX/go,samanalysis/go,polyverse-security/go,nawawi/go,theass/go,ericsnowcurrently/go,linux-on-ibm-z/go,Cofyc/go,snowsnail/go,xiuzhifu/go,mwhudson/go,vsekhar/elastic-go,josharian/go,momchil-velikov/go,snowsnail/go,theass/go,linux-on-ibm-z/go,derekmarcotte/go,kim-racktop/go,zhangg/go,rachtsingh/gogojuice,Badredapple/go,jacobsa/go,ichu501/go,codestation/go,stormltf/go,Pulgafree/go,vanloswang/go,danielsoro/go,odeke-em/go,odeke-em/go,suncycheng/go,josharian/go,b54898533/go,theass/go,zhangg/go,Endika/go,devpadawan/go,b54898533/go,ifagnosticism/go,fjballest/golang,skatsuta/go,joshsammut/go,ichu501/go,jdhenke/go,vanloswang/go,NunoEdgarGub1/go,akutz/go,jacobsa/go,gdey/go,momchil-velikov/go,vanloswang/go,likesea/go,vanloswang/go,polyverse-security/go,Pulgafree/go,kim-racktop/go,goodlang/good,NunoEdgarGub1/go,momchil-velikov/go,christopher-henderson/Go,ichu501/go,nawawi/go,snowsnail/go,suncycheng/go,ImJasonH/go,cloudflare/go,roth1002/go,cookerzhu/go,sndnvaps/go,kim-racktop/go,xiuzhifu/go,odeke-em/go,alex-zhang/go,sndnvaps/go,CarterTsai/go,stormltf/go,danielsoro/go,cloudflare/go,ifagnosticism/go,binarycrusader/go,Jordanzuo/go,vsekhar/elastic-go,GeorgiCodes/go,josharian/go,cyberroadie/go,danielsoro/go,likesea/go,sndnvaps/go,joshsammut/go,Badredapple/go,dpatel06/go,miolini/go,devpadawan/go,Samurais/go,kim-racktop/go,binarycrusader/go,suncycheng/go,b54898533/go,momchil-velikov/go,mwhudson/go,CarterTsai/go,alex-zhang/go,jacobhaven/go,likesea/go,devpadawan/go,vanloswang/go,deft-code/go,Cofyc/go,mikekap/go,binarycrusader/go,binarycrusader/go,Jordanzuo/go,joshsammut/go,snowsnail/go,jacobsa/go,jonasi/go,derekmarcotte/go,nawawi/go,codestation/go,josharian/go,dpatel06/go,Cofyc/go,fjballest/golang,akutz/go,snowsnail/go,samanalysis/go,Samurais/go,golang/go,samanalysis/go,b54898533/go,likesea/go,yasarkunduz/go,gdey/go,nawawi/go,ganboing/go-esx,Endika/go,cyberroadie/go,b54898533/go,ImJasonH/go,xiuzhifu/go,Cofyc/go,malvira/go,skatsuta/go,mikekap/go,ichu501/go,alex-zhang/go,stormltf/go,golang/go,Cofyc/go,ichu501/go,malvira/go,derekmarcotte/go,danielsoro/go,dterei/go,rachtsingh/gogojuice,alex-zhang/go,mwhudson/go,Samurais/go,ichu501/go,stormltf/go,jacobhaven/go,b54898533/go,cyberroadie/go,jonasi/go,vsekhar/elastic-go,jacobsa/go,derekmarcotte/go,Samurais/go,ganboing/go-esx,theif519/go,dpatel06/go,jacobhaven/go,gdey/go,ImJasonH/go,nawawi/go,dterei/go,roth1002/go,ericsnowcurrently/go,devpadawan/go,rachtsingh/gogojuice,dterei/go,derekmarcotte/go,jonasi/go,joshsammut/go,GeorgiCodes/go,mikekap/go,golang/go,jacobsa/go,malvira/go,fjballest/golang,jacobhaven/go,vsekhar/elastic-go,goodlang/good,NunoEdgarGub1/go,akutz/go,Badredapple/go,joshsammut/go,jdhenke/go,dterei/go,beealone/go,jdhenke/go,deft-code/go,jacobhaven/go,miolini/go,b54898533/go,beealone/go,CarterTsai/go,CAFxX/go,suncycheng/go,deft-code/go,skatsuta/go,Samurais/go,theass/go,samanalysis/go,kim-racktop/go,joshsammut/go,nawawi/go,samanalysis/go,theass/go,polyverse-security/go,CarterTsai/go,sndnvaps/go,golang/go,malvira/go,polyverse-security/go,goodlang/good,Pulgafree/go,golang/go,Badredapple/go,cloudflare/go,akutz/go,likesea/go,theif519/go,vanloswang/go,stormltf/go,ifagnosticism/go,Jordanzuo/go,4ad/go,myPublicGit/go,vsekhar/elastic-go,deft-code/go,cookerzhu/go,goodlang/good,Jordanzuo/go,binarycrusader/go,Pulgafree/go,ganboing/go-esx,odeke-em/go,Jordanzuo/go,akutz/go,golang/go,goodlang/good,cookerzhu/go,ImJasonH/go,theif519/go,snowsnail/go,ifagnosticism/go,cookerzhu/go,cyberroadie/go,danielsoro/go,momchil-velikov/go,ericsnowcurrently/go,cookerzhu/go,dpatel06/go,derekmarcotte/go,ganboing/go-esx,samanalysis/go,skatsuta/go,GeorgiCodes/go,cyberroadie/go,Cofyc/go,cookerzhu/go,Badredapple/go,Cofyc/go,xiuzhifu/go,jacobsa/go,Jordanzuo/go,jdhenke/go,xiuzhifu/go,josharian/go,zhangg/go,Jordanzuo/go,theif519/go,linux-on-ibm-z/go,ichu501/go,miolini/go,nawawi/go,jacobhaven/go,zhangg/go,yasarkunduz/go,roth1002/go,joshsammut/go,cookerzhu/go,malvira/go,rachtsingh/gogojuice,beealone/go,myPublicGit/go,odeke-em/go,CarterTsai/go,ganboing/go-esx,jonasi/go,linux-on-ibm-z/go,Badredapple/go,jacobsa/go,miolini/go,ImJasonH/go,4ad/go,CarterTsai/go,jacobhaven/go,ganboing/go-esx,suncycheng/go,kim-racktop/go,theif519/go,likesea/go,codestation/go,miolini/go,CAFxX/go,gdey/go,likesea/go,vanloswang/go,linux-on-ibm-z/go,skatsuta/go,myPublicGit/go,Endika/go,4ad/go,polyverse-security/go,Pulgafree/go,cookerzhu/go,GeorgiCodes/go,ImJasonH/go,mwhudson/go,deft-code/go,theass/go,miolini/go,cloudflare/go,josharian/go,ericsnowcurrently/go,kim-racktop/go,roth1002/go,alex-zhang/go,CAFxX/go,cyberroadie/go,danielsoro/go,sndnvaps/go,yasarkunduz/go,Endika/go,gdey/go,ifagnosticism/go,ericsnowcurrently/go,Jordanzuo/go,yasarkunduz/go,dpatel06/go,4ad/go,samanalysis/go,zhangg/go,Pulgafree/go,4ad/go,mikekap/go,skatsuta/go,ifagnosticism/go,yasarkunduz/go,beealone/go,jonasi/go,zhangg/go,Pulgafree/go,danielsoro/go,cloudflare/go,dterei/go,ericsnowcurrently/go,cyberroadie/go,linux-on-ibm-z/go,dpatel06/go,nawawi/go,odeke-em/go,GeorgiCodes/go,jonasi/go,codestation/go,stormltf/go,ImJasonH/go,suncycheng/go,4ad/go,myPublicGit/go,Badredapple/go,gdey/go,roth1002/go,rachtsingh/gogojuice,codestation/go,CAFxX/go,NunoEdgarGub1/go,alex-zhang/go,stormltf/go,malvira/go,polyverse-security/go,Pulgafree/go,cyberroadie/go,suncycheng/go,mwhudson/go,jdhenke/go,kim-racktop/go,vsekhar/elastic-go,dterei/go,NunoEdgarGub1/go,b54898533/go,mwhudson/go,binarycrusader/go,ganboing/go-esx,devpadawan/go,deft-code/go,Endika/go,goodlang/good,ichu501/go,4ad/go,roth1002/go,deft-code/go,jacobhaven/go,fjballest/golang,Samurais/go,momchil-velikov/go,sndnvaps/go,sndnvaps/go,malvira/go,polyverse-security/go,vsekhar/elastic-go,akutz/go,CAFxX/go,miolini/go,sndnvaps/go,devpadawan/go,mikekap/go,fjballest/golang,odeke-em/go,codestation/go,gdey/go,akutz/go,vsekhar/elastic-go,NunoEdgarGub1/go,stormltf/go,GeorgiCodes/go,cloudflare/go,Endika/go,theif519/go,yasarkunduz/go,Badredapple/go,linux-on-ibm-z/go,myPublicGit/go,devpadawan/go,jdhenke/go,xiuzhifu/go,mwhudson/go,snowsnail/go,momchil-velikov/go,derekmarcotte/go,goodlang/good,beealone/go,dterei/go,binarycrusader/go,mikekap/go,dpatel06/go,golang/go,cloudflare/go,yasarkunduz/go,danielsoro/go,GeorgiCodes/go,ImJasonH/go,josharian/go,myPublicGit/go,rachtsingh/gogojuice,snowsnail/go,roth1002/go,zhangg/go,odeke-em/go,myPublicGit/go,Endika/go,goodlang/good,ganboing/go-esx,jacobsa/go,mikekap/go,yasarkunduz/go,Cofyc/go,theif519/go,Endika/go,ericsnowcurrently/go,polyverse-security/go,GeorgiCodes/go,malvira/go,codestation/go,rachtsingh/gogojuice,momchil-velikov/go,NunoEdgarGub1/go