7e0af973 | 09-Nov-2023 |
zhanglinjuan <[email protected]> |
DecodeUnitComp: break RAW dependence between uops with the same vd
For indexed instructions, VLSU will concatenate all the uops that write the same logic vd register and writeback only once for all
DecodeUnitComp: break RAW dependence between uops with the same vd
For indexed instructions, VLSU will concatenate all the uops that write the same logic vd register and writeback only once for all these uops. However, these uops share the same lsrc(2)/old vd and the same ldest/vd that is equal to old vd, which leads to data dependence between the uops. Therefore there will be deadlock for indexed instructions with emul > lmul.
Assume N = emul/lmul. To break the deadlock, only the first uop will read old vd as lsrc(2), and the rest N-1 uops will read temporary vector register.
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