We've talked about this before, caching state to reduce the amount of computation that happens looking up each TB.
I know that Peter has been concerned that we would not be able to reliably maintain all of the places that need to be updates to keep this up-to-date. Well, modulo dirty tricks within linux-user, it appears as if exception delivery and return, plus after every TB-ending write to a system register is sufficient. There seems to be a noticable improvement, although wall-time is harder to come by -- all of my system-level measurements include user input, and my user-level measurements seem to be too small to matter. r~ Richard Henderson (4): target/arm: Split out recompute_hflags et al target/arm: Rebuild hflags at el changes and MSR writes target/arm: Assert hflags is correct in cpu_get_tb_cpu_state target/arm: Rely on hflags correct in cpu_get_tb_cpu_state target/arm/cpu.h | 22 ++- target/arm/helper.h | 3 + target/arm/internals.h | 4 + linux-user/syscall.c | 1 + target/arm/cpu.c | 1 + target/arm/helper-a64.c | 3 + target/arm/helper.c | 267 ++++++++++++++++++++++--------------- target/arm/machine.c | 1 + target/arm/op_helper.c | 1 + target/arm/translate-a64.c | 6 +- target/arm/translate.c | 14 +- 11 files changed, 204 insertions(+), 119 deletions(-) -- 2.17.1
