[dev.ssa] cmd/compile/internal/gc: Fix constant shift generation
[dev.ssa] cmd/compile/internal/gc: Fix constant shift generation

Change-Id: Ib142185de3f6e4d2f4983511c063492529d8fb8a
Reviewed-on: https://go-review.googlesource.com/11656
Reviewed-by: Michael Matloob <1b6ee578db4d95965bf73831a3b5b715e4ec96c4@gmail.com>

momchil-velikov/go,josharian/go,codestation/go,vanloswang/go,christopher-henderson/Go,derekmarcotte/go,Samurais/go,codestation/go,ganboing/go-esx,cloudflare/go,derekmarcotte/go,codestation/go,Cofyc/go,cyberroadie/go,ganboing/go-esx,derekmarcotte/go,theif519/go,cyberroadie/go,suncycheng/go,polyverse-security/go,vsekhar/elastic-go,akutz/go,ganboing/go-esx,4ad/go,Cofyc/go,mwhudson/go,goodlang/good,Samurais/go,polyverse-security/go,akutz/go,mwhudson/go,ImJasonH/go,theif519/go,vanloswang/go,codestation/go,miolini/go,nawawi/go,Cofyc/go,momchil-velikov/go,ganboing/go-esx,josharian/go,ImJasonH/go,golang/go,linux-on-ibm-z/go,vsekhar/elastic-go,golang/go,Samurais/go,linux-on-ibm-z/go,CAFxX/go,akutz/go,nawawi/go,theif519/go,binarycrusader/go,ImJasonH/go,linux-on-ibm-z/go,cyberroadie/go,akutz/go,Cofyc/go,mwhudson/go,goodlang/good,binarycrusader/go,vanloswang/go,miolini/go,cloudflare/go,josharian/go,4ad/go,derekmarcotte/go,CAFxX/go,vanloswang/go,theif519/go,akutz/go,akutz/go,goodlang/good,binarycrusader/go,binarycrusader/go,suncycheng/go,4ad/go,CAFxX/go,polyverse-security/go,josharian/go,Samurais/go,ImJasonH/go,cyberroadie/go,linux-on-ibm-z/go,polyverse-security/go,polyverse-security/go,momchil-velikov/go,mwhudson/go,derekmarcotte/go,cyberroadie/go,suncycheng/go,miolini/go,golang/go,ImJasonH/go,binarycrusader/go,goodlang/good,ImJasonH/go,goodlang/good,codestation/go,CAFxX/go,cloudflare/go,golang/go,Samurais/go,nawawi/go,polyverse-security/go,vsekhar/elastic-go,momchil-velikov/go,miolini/go,nawawi/go,CAFxX/go,momchil-velikov/go,linux-on-ibm-z/go,4ad/go,codestation/go,nawawi/go,golang/go,4ad/go,4ad/go,miolini/go,linux-on-ibm-z/go,josharian/go,cloudflare/go,ganboing/go-esx,nawawi/go,theif519/go,Cofyc/go,CAFxX/go,4ad/go,vanloswang/go,polyverse-security/go,suncycheng/go,ganboing/go-esx,mwhudson/go,cloudflare/go,golang/go,cloudflare/go,goodlang/good,miolini/go,Cofyc/go,ganboing/go-esx,vanloswang/go,miolini/go,akutz/go,ImJasonH/go,nawawi/go,cloudflare/go,vsekhar/elastic-go,Cofyc/go,golang/go,cloudflare/go,codestation/go,4ad/go,Cofyc/go,goodlang/good,nawawi/go,linux-on-ibm-z/go,vanloswang/go,binarycrusader/go,derekmarcotte/go,cyberroadie/go,miolini/go,momchil-velikov/go,mwhudson/go,theif519/go,mwhudson/go,vsekhar/elastic-go,vanloswang/go,cyberroadie/go,suncycheng/go,mwhudson/go,CAFxX/go,ImJasonH/go,Samurais/go,CAFxX/go,binarycrusader/go,momchil-velikov/go,Samurais/go,golang/go,goodlang/good,josharian/go,Samurais/go,suncycheng/go,josharian/go,vsekhar/elastic-go,suncycheng/go,josharian/go,akutz/go,linux-on-ibm-z/go,vsekhar/elastic-go,theif519/go,codestation/go,derekmarcotte/go,ganboing/go-esx,theif519/go,momchil-velikov/go,vsekhar/elastic-go,polyverse-security/go,suncycheng/go,derekmarcotte/go,cyberroadie/go,binarycrusader/go