Backend,Frontend: pass flag of FtqPtr to TargetMem to avoid read out-of-date pred target - Githubissues

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Backend,Frontend: pass flag of FtqPtr to TargetMem to avoid read out-of-date pred target #3114

Open Lemover opened 6 days ago

Lemover commented 6 days ago

Hold newest predict target everytime it updated by frontend.
Don't use out-of-date predict value even if FtqIdx match.

XiangShanRobot commented 5 days ago

[Generated by IPC robot] commit: 3f727c4238d983efd3d3dd706b661fe859c5548e	commit	astar	copy_and_run	coremark	gcc	gromacs	lbm	linux	mcf	microbench	milc	namd	povray	wrf	xalancbmk
3f727c4	1.793	0.452	2.016	1.160	2.933	2.504	2.200	0.931	1.354	1.349	3.183	2.519	2.377	2.871

master branch:	commit	astar	copy_and_run	coremark	gcc	gromacs	lbm	linux	mcf	microbench	milc	namd	povray	wrf	xalancbmk
762f2b3	1.812	0.451	2.043	1.199	2.941	2.507	2.196	0.934	1.373	1.397	3.181	2.669	2.403	2.961
91f3148	1.812	0.451	2.047	1.199	2.941	2.507	2.196	0.934	1.373	1.397	3.181	2.669	2.403	2.961
d77cf63	1.812	0.451	2.043	1.199	2.941	2.507	2.196	0.934	1.373	1.397	3.181	2.669	2.403	2.961
d64fbe5	1.812	0.451	2.043	1.199	2.941	2.507	2.196	0.934	1.373	1.397	3.181	2.669	2.403	2.961
939a787	1.812	0.451	2.047	1.199	2.941	2.507	2.196	0.934	1.373	1.397	3.181	2.669	2.403	2.961
9705db6	1.812	0.451	2.047	1.199	2.941	2.507	2.196	0.934	1.373	1.397	3.181	2.669	2.403	2.961
78d7c65	1.812	0.451	2.043	1.199	2.941	2.507	2.196	0.934	1.373	1.397	3.181	2.669	2.403	2.961
5c1e8bf	1.812	0.451	2.043	1.199	2.941	2.507	2.196	0.934	1.373	1.397	3.181	2.669	2.403	2.961
7c26eb0	1.809	0.451	2.043	1.190	2.940	2.496	2.197	0.932	1.373	1.411	3.181	2.669	2.403	2.948
1436b76	1.811	0.451	2.047	1.190	2.940	2.496	2.197	0.932	1.373	1.411	3.181	2.669	2.403	2.948

Lemover commented 5 days ago

Encounter unexpected performance decrease. need fix it before merging.