[sil-value-tracking] Let computeSignBit make use of of the fact that StrideOf, StrideOfNonZero and AlignOf are known to return non-negative results, i.e. their sign bit is always 0.
[sil-value-tracking] Let computeSignBit make use of of the fact that StrideOf, StrideOfNonZero and AlignOf are known to return non-negative results, i.e. their sign bit is always 0.

Swift SVN r21771

sschiau/swift,bitjammer/swift,huonw/swift,slavapestov/swift,allevato/swift,therealbnut/swift,shajrawi/swift,hughbe/swift,lorentey/swift,allevato/swift,MukeshKumarS/Swift,codestergit/swift,stephentyrone/swift,JaSpa/swift,stephentyrone/swift,emilstahl/swift,tardieu/swift,swiftix/swift,bitjammer/swift,austinzheng/swift,tardieu/swift,aschwaighofer/swift,austinzheng/swift,uasys/swift,johnno1962d/swift,adrfer/swift,djwbrown/swift,lorentey/swift,apple/swift,IngmarStein/swift,brentdax/swift,jtbandes/swift,IngmarStein/swift,brentdax/swift,slavapestov/swift,hooman/swift,swiftix/swift.old,huonw/swift,shajrawi/swift,danielmartin/swift,slavapestov/swift,milseman/swift,xwu/swift,austinzheng/swift,johnno1962d/swift,felix91gr/swift,shajrawi/swift,JGiola/swift,brentdax/swift,jmgc/swift,alblue/swift,dduan/swift,jckarter/swift,jopamer/swift,JGiola/swift,tkremenek/swift,harlanhaskins/swift,dreamsxin/swift,swiftix/swift,frootloops/swift,devincoughlin/swift,danielmartin/swift,tkremenek/swift,therealbnut/swift,cbrentharris/swift,karwa/swift,khizkhiz/swift,glessard/swift,Ivacker/swift,tjw/swift,IngmarStein/swift,natecook1000/swift,swiftix/swift,Ivacker/swift,apple/swift,mightydeveloper/swift,jckarter/swift,kusl/swift,jtbandes/swift,MukeshKumarS/Swift,swiftix/swift.old,hughbe/swift,mightydeveloper/swift,kusl/swift,jopamer/swift,ken0nek/swift,russbishop/swift,arvedviehweger/swift,kusl/swift,OscarSwanros/swift,nathawes/swift,arvedviehweger/swift,cbrentharris/swift,bitjammer/swift,sdulal/swift,karwa/swift,return/swift,alblue/swift,jopamer/swift,tkremenek/swift,johnno1962d/swift,xwu/swift,emilstahl/swift,kperryua/swift,kperryua/swift,sschiau/swift,allevato/swift,gregomni/swift,ken0nek/swift,ben-ng/swift,JaSpa/swift,glessard/swift,CodaFi/swift,amraboelela/swift,brentdax/swift,IngmarStein/swift,cbrentharris/swift,deyton/swift,karwa/swift,IngmarStein/swift,emilstahl/swift,danielmartin/swift,gottesmm/swift,kusl/swift,huonw/swift,manavgabhawala/swift,ken0nek/swift,kstaring/swift,kusl/swift,gottesmm/swift,alblue/swift,MukeshKumarS/Swift,kusl/swift,harlanhaskins/swift,gmilos/swift,arvedviehweger/swift,tardieu/swift,felix91gr/swift,Jnosh/swift,nathawes/swift,MukeshKumarS/Swift,codestergit/swift,cbrentharris/swift,benlangmuir/swift,roambotics/swift,mightydeveloper/swift,zisko/swift,milseman/swift,natecook1000/swift,therealbnut/swift,airspeedswift/swift,modocache/swift,Ivacker/swift,arvedviehweger/swift,gribozavr/swift,djwbrown/swift,xedin/swift,Ivacker/swift,johnno1962d/swift,tinysun212/swift-windows,jckarter/swift,KrishMunot/swift,hughbe/swift,johnno1962d/swift,uasys/swift,nathawes/swift,practicalswift/swift,dduan/swift,tinysun212/swift-windows,devincoughlin/swift,tardieu/swift,slavapestov/swift,apple/swift,karwa/swift,gottesmm/swift,devincoughlin/swift,lorentey/swift,ahoppen/swift,benlangmuir/swift,codestergit/swift,brentdax/swift,aschwaighofer/swift,kperryua/swift,swiftix/swift,tkremenek/swift,roambotics/swift,xwu/swift,gregomni/swift,jmgc/swift,return/swift,uasys/swift,frootloops/swift,dduan/swift,arvedviehweger/swift,parkera/swift,xwu/swift,parkera/swift,sdulal/swift,SwiftAndroid/swift,stephentyrone/swift,practicalswift/swift,nathawes/swift,xedin/swift,dreamsxin/swift,sdulal/swift,kperryua/swift,amraboelela/swift,nathawes/swift,dduan/swift,lorentey/swift,ben-ng/swift,zisko/swift,kentya6/swift,sschiau/swift,aschwaighofer/swift,deyton/swift,glessard/swift,nathawes/swift,codestergit/swift,slavapestov/swift,benlangmuir/swift,allevato/swift,stephentyrone/swift,codestergit/swift,jmgc/swift,LeoShimonaka/swift,shajrawi/swift,ben-ng/swift,manavgabhawala/swift,khizkhiz/swift,sschiau/swift,xwu/swift,shahmishal/swift,JGiola/swift,gribozavr/swift,jckarter/swift,felix91gr/swift,CodaFi/swift,huonw/swift,gottesmm/swift,manavgabhawala/swift,russbishop/swift,zisko/swift,adrfer/swift,manavgabhawala/swift,airspeedswift/swift,aschwaighofer/swift,SwiftAndroid/swift,frootloops/swift,ken0nek/swift,manavgabhawala/swift,aschwaighofer/swift,kentya6/swift,gribozavr/swift,benlangmuir/swift,huonw/swift,LeoShimonaka/swift,calebd/swift,huonw/swift,CodaFi/swift,dduan/swift,jopamer/swift,gribozavr/swift,hooman/swift,emilstahl/swift,sschiau/swift,kentya6/swift,allevato/swift,ken0nek/swift,ken0nek/swift,amraboelela/swift,modocache/swift,MukeshKumarS/Swift,JaSpa/swift,Jnosh/swift,sschiau/swift,CodaFi/swift,atrick/swift,lorentey/swift,jmgc/swift,mightydeveloper/swift,kusl/swift,swiftix/swift,KrishMunot/swift,hooman/swift,shajrawi/swift,djwbrown/swift,Jnosh/swift,kstaring/swift,alblue/swift,sschiau/swift,ahoppen/swift,xedin/swift,austinzheng/swift,mightydeveloper/swift,adrfer/swift,practicalswift/swift,practicalswift/swift,parkera/swift,sdulal/swift,KrishMunot/swift,tinysun212/swift-windows,return/swift,jopamer/swift,Ivacker/swift,tardieu/swift,shahmishal/swift,felix91gr/swift,calebd/swift,huonw/swift,sdulal/swift,hughbe/swift,devincoughlin/swift,harlanhaskins/swift,hooman/swift,atrick/swift,zisko/swift,MukeshKumarS/Swift,sdulal/swift,JaSpa/swift,gregomni/swift,milseman/swift,jtbandes/swift,swiftix/swift.old,glessard/swift,jckarter/swift,parkera/swift,felix91gr/swift,danielmartin/swift,deyton/swift,swiftix/swift,therealbnut/swift,return/swift,gmilos/swift,danielmartin/swift,swiftix/swift,uasys/swift,emilstahl/swift,xedin/swift,djwbrown/swift,KrishMunot/swift,alblue/swift,JGiola/swift,xedin/swift,tjw/swift,sschiau/swift,natecook1000/swift,tardieu/swift,SwiftAndroid/swift,tardieu/swift,amraboelela/swift,xwu/swift,apple/swift,OscarSwanros/swift,calebd/swift,gmilos/swift,ben-ng/swift,johnno1962d/swift,austinzheng/swift,karwa/swift,codestergit/swift,rudkx/swift,kperryua/swift,gottesmm/swift,harlanhaskins/swift,nathawes/swift,atrick/swift,JaSpa/swift,natecook1000/swift,ahoppen/swift,jckarter/swift,aschwaighofer/swift,karwa/swift,tkremenek/swift,jopamer/swift,mightydeveloper/swift,zisko/swift,parkera/swift,gribozavr/swift,khizkhiz/swift,jmgc/swift,tjw/swift,gribozavr/swift,parkera/swift,hooman/swift,stephentyrone/swift,hughbe/swift,LeoShimonaka/swift,deyton/swift,bitjammer/swift,austinzheng/swift,khizkhiz/swift,frootloops/swift,stephentyrone/swift,cbrentharris/swift,jtbandes/swift,jtbandes/swift,jtbandes/swift,IngmarStein/swift,adrfer/swift,Jnosh/swift,amraboelela/swift,xedin/swift,practicalswift/swift,hughbe/swift,johnno1962d/swift,calebd/swift,swiftix/swift.old,gmilos/swift,devincoughlin/swift,rudkx/swift,tinysun212/swift-windows,KrishMunot/swift,russbishop/swift,devincoughlin/swift,deyton/swift,tjw/swift,bitjammer/swift,bitjammer/swift,ahoppen/swift,glessard/swift,parkera/swift,parkera/swift,CodaFi/swift,CodaFi/swift,karwa/swift,kentya6/swift,allevato/swift,practicalswift/swift,frootloops/swift,russbishop/swift,Ivacker/swift,cbrentharris/swift,JGiola/swift,kentya6/swift,rudkx/swift,harlanhaskins/swift,devincoughlin/swift,return/swift,shahmishal/swift,karwa/swift,airspeedswift/swift,swiftix/swift.old,gottesmm/swift,khizkhiz/swift,milseman/swift,roambotics/swift,LeoShimonaka/swift,milseman/swift,lorentey/swift,rudkx/swift,calebd/swift,russbishop/swift,adrfer/swift,djwbrown/swift,stephentyrone/swift,return/swift,modocache/swift,kstaring/swift,hughbe/swift,airspeedswift/swift,amraboelela/swift,JaSpa/swift,gregomni/swift,gmilos/swift,austinzheng/swift,uasys/swift,adrfer/swift,amraboelela/swift,gribozavr/swift,roambotics/swift,OscarSwanros/swift,cbrentharris/swift,uasys/swift,cbrentharris/swift,natecook1000/swift,shahmishal/swift,khizkhiz/swift,tjw/swift,mightydeveloper/swift,atrick/swift,therealbnut/swift,Jnosh/swift,brentdax/swift,jckarter/swift,slavapestov/swift,rudkx/swift,xwu/swift,KrishMunot/swift,airspeedswift/swift,SwiftAndroid/swift,deyton/swift,modocache/swift,tinysun212/swift-windows,shajrawi/swift,khizkhiz/swift,tkremenek/swift,ben-ng/swift,gregomni/swift,kstaring/swift,calebd/swift,danielmartin/swift,shahmishal/swift,manavgabhawala/swift,LeoShimonaka/swift,modocache/swift,kusl/swift,devincoughlin/swift,alblue/swift,MukeshKumarS/Swift,atrick/swift,gmilos/swift,return/swift,tinysun212/swift-windows,kstaring/swift,shajrawi/swift,kentya6/swift,Jnosh/swift,emilstahl/swift,allevato/swift,modocache/swift,kstaring/swift,JaSpa/swift,practicalswift/swift,roambotics/swift,russbishop/swift,brentdax/swift,modocache/swift,airspeedswift/swift,uasys/swift,kentya6/swift,rudkx/swift,jopamer/swift,tinysun212/swift-windows,gregomni/swift,lorentey/swift,emilstahl/swift,shajrawi/swift,arvedviehweger/swift,frootloops/swift,russbishop/swift,frootloops/swift,gribozavr/swift,sdulal/swift,harlanhaskins/swift,arvedviehweger/swift,LeoShimonaka/swift,benlangmuir/swift,atrick/swift,OscarSwanros/swift,tjw/swift,kperryua/swift,zisko/swift,ahoppen/swift,swiftix/swift.old,Ivacker/swift,dduan/swift,harlanhaskins/swift,shahmishal/swift,natecook1000/swift,practicalswift/swift,adrfer/swift,sdulal/swift,hooman/swift,hooman/swift,apple/swift,milseman/swift,benlangmuir/swift,alblue/swift,danielmartin/swift,tjw/swift,kperryua/swift,SwiftAndroid/swift,ben-ng/swift,natecook1000/swift,LeoShimonaka/swift,therealbnut/swift,roambotics/swift,airspeedswift/swift,lorentey/swift,SwiftAndroid/swift,mightydeveloper/swift,LeoShimonaka/swift,ahoppen/swift,shahmishal/swift,manavgabhawala/swift,swiftix/swift.old,OscarSwanros/swift,xedin/swift,felix91gr/swift,djwbrown/swift,gottesmm/swift,jmgc/swift,jtbandes/swift,milseman/swift,therealbnut/swift,tkremenek/swift,kstaring/swift,xedin/swift,emilstahl/swift,felix91gr/swift,IngmarStein/swift,ken0nek/swift,shahmishal/swift,Ivacker/swift,swiftix/swift.old,CodaFi/swift,ben-ng/swift,jmgc/swift,bitjammer/swift,kentya6/swift,KrishMunot/swift,aschwaighofer/swift,gmilos/swift,slavapestov/swift,glessard/swift,apple/swift,dduan/swift,JGiola/swift,OscarSwanros/swift,OscarSwanros/swift,codestergit/swift,calebd/swift,zisko/swift,Jnosh/swift,deyton/swift,djwbrown/swift,SwiftAndroid/swift