Refactored Floating point division special case detection to avoid spurious trigger on Y for sqrt)

This commit is contained in:
David Harris 2023-03-02 20:00:47 -08:00
parent c761fb1054
commit d51d93a3a8

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@ -60,9 +60,9 @@ module fdivsqrtfsm(
assign IFDivStartE = (FDivStartE | (IDivStartE & `IDIV_ON_FPU)) & (state == IDLE) & ~StallM;
assign FDivDoneE = (state == DONE);
assign FDivBusyE = (state == BUSY) | IFDivStartE;
// terminate immediately on special cases
assign FSpecialCaseE = XZeroE | (YZeroE&~SqrtE) | XInfE | YInfE | XNaNE | YNaNE | (XsE&SqrtE);
assign FSpecialCaseE = XZeroE | | XInfE | XNaNE | (XsE&SqrtE) | (YZeroE | YInfE | YNaNE)&~SqrtE;
if (`IDIV_ON_FPU) assign SpecialCaseE = IntDivE ? ISpecialCaseE : FSpecialCaseE;
else assign SpecialCaseE = FSpecialCaseE;
flopenr #(1) SpecialCaseReg(clk, reset, IFDivStartE, SpecialCaseE, SpecialCaseM); // save SpecialCase for checking in fdivsqrtpostproc