diff --git a/src/cpu/o3/FuncUnitConfig.py b/src/cpu/o3/FuncUnitConfig.py index 34c56163d0..0f5efb7767 100644 --- a/src/cpu/o3/FuncUnitConfig.py +++ b/src/cpu/o3/FuncUnitConfig.py @@ -39,6 +39,7 @@ # Authors: Kevin Lim from m5.SimObject import SimObject +from m5.defines import buildEnv from m5.params import * from FuncUnit import * @@ -49,6 +50,15 @@ class IntALU(FUDesc): class IntMultDiv(FUDesc): opList = [ OpDesc(opClass='IntMult', opLat=3), OpDesc(opClass='IntDiv', opLat=20, issueLat=19) ] + + # DIV and IDIV instructions in x86 are implemented using a loop which + # issues division microops. The latency of these microops should really be + # one (or a small number) cycle each since each of these computes one bit + # of the quotient. + if buildEnv['TARGET_ISA'] in ('x86'): + opList[1].opLat=1 + opList[1].issueLat=1 + count=2 class FP_ALU(FUDesc):