Fixed FImage tests on Darwin/x64
Fixed FImage tests on Darwin/x64

It seemingly crashes whenever images are unrolled
or vectorized over the _y_ dimension.
kenkuang1213/Halide,dan-tull/Halide,dougkwan/Halide,ayanazmat/Halide,dougkwan/Halide,dan-tull/Halide,ayanazmat/Halide,tdenniston/Halide,myrtleTree33/Halide,lglucin/Halide,kgnk/Halide,psuriana/Halide,psuriana/Halide,ronen/Halide,aam/Halide,kgnk/Halide,kenkuang1213/Halide,dan-tull/Halide,jiawen/Halide,ayanazmat/Halide,adasworks/Halide,aam/Halide,delcypher/Halide,aam/Halide,mcanthony/Halide,gchauras/Halide,fengzhyuan/Halide,aam/Halide,mcanthony/Halide,jiawen/Halide,delcypher/Halide,adasworks/Halide,tdenniston/Halide,psuriana/Halide,fengzhyuan/Halide,jiawen/Halide,ronen/Halide,rodrigob/Halide,delcypher/Halide,ronen/Halide,tdenniston/Halide,delcypher/Halide,adasworks/Halide,lglucin/Halide,kenkuang1213/Halide,myrtleTree33/Halide,fengzhyuan/Halide,psuriana/Halide,smxlong/Halide,kgnk/Halide,delcypher/Halide,smxlong/Halide,kgnk/Halide,lglucin/Halide,rodrigob/Halide,dougkwan/Halide,tdenniston/Halide,mcanthony/Halide,psuriana/Halide,jiawen/Halide,tdenniston/Halide,lglucin/Halide,dougkwan/Halide,ayanazmat/Halide,kenkuang1213/Halide,delcypher/Halide,kgnk/Halide,mcanthony/Halide,rodrigob/Halide,delcypher/Halide,kenkuang1213/Halide,ronen/Halide,myrtleTree33/Halide,gchauras/Halide,tdenniston/Halide,myrtleTree33/Halide,myrtleTree33/Halide,fengzhyuan/Halide,mikeseven/Halide,lglucin/Halide,damienfir/Halide,damienfir/Halide,mcanthony/Halide,dougkwan/Halide,fengzhyuan/Halide,aam/Halide,kgnk/Halide,mcanthony/Halide,damienfir/Halide,jiawen/Halide,damienfir/Halide,dan-tull/Halide,kenkuang1213/Halide,gchauras/Halide,gchauras/Halide,mikeseven/Halide,ronen/Halide,ronen/Halide,gchauras/Halide,adasworks/Halide,smxlong/Halide,ronen/Halide,aam/Halide,mikeseven/Halide,lglucin/Halide,dan-tull/Halide,smxlong/Halide,damienfir/Halide,myrtleTree33/Halide,jiawen/Halide,psuriana/Halide,adasworks/Halide,dan-tull/Halide,adasworks/Halide,tdenniston/Halide,fengzhyuan/Halide,rodrigob/Halide,rodrigob/Halide,smxlong/Halide,kgnk/Halide,myrtleTree33/Halide,mcanthony/Halide,damienfir/Halide,ayanazmat/Halide,fengzhyuan/Halide,mcanthony/Halide,ronen/Halide,adasworks/Halide,ayanazmat/Halide,lglucin/Halide,jiawen/Halide,myrtleTree33/Halide,ayanazmat/Halide,delcypher/Halide,rodrigob/Halide,psuriana/Halide,damienfir/Halide,smxlong/Halide,fengzhyuan/Halide,dougkwan/Halide,kenkuang1213/Halide,mikeseven/Halide,rodrigob/Halide,mikeseven/Halide,kgnk/Halide,dan-tull/Halide,tdenniston/Halide,smxlong/Halide,gchauras/Halide,ayanazmat/Halide,smxlong/Halide,kenkuang1213/Halide,rodrigob/Halide,damienfir/Halide,adasworks/Halide,aam/Halide,dougkwan/Halide,dougkwan/Halide,dan-tull/Halide