cmd/compile: fix off-by-1 in getr
cmd/compile: fix off-by-1 in getr

Introduced by (and missed during code review of) golang.org/cl/19847.

Change-Id: I03b76f36e5da69c31730380592dfa1c32570e17f
Reviewed-on: https://go-review.googlesource.com/19912
Run-TryBot: Matthew Dempsky <e56ac2c500064424afac424d4b5e53bd0570a731@google.com>
Reviewed-by: Robert Griesemer <a6752097faebf1f02d80107d77a9be009089afe3@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>

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