fix numerical overflow in bit shift operation #41
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In `xsim`, the limited precision of the shift-right argument causes overflow when the shift amount is multiplied by data width, leading to a result of always 0. This creates an explicitly sized shift right argument to fix this small compatibility issue.
alexforencich
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In
xsim, the limited bit width of the shift-right argumentr_grant_encodedcauses overflow when the shift amount is multiplied by DATA_WIDTH, leading to a result of always 0 (for example, on a 32-bit wide 3x1 crossbar,r_grant_encodedwould have a bit width of 2 bits, which is then multiplied by 32, which yields 0 for any value ofr_grant_encodedthat is multiplied and then stuffed back into its 2-bit specified width).This creates an explicitly sized shift right argument to fix this small compatibility issue. I'm not actually sure if this is a bug is
xsim(this is the Xilinx Vivado simulator) or if it's an issue with the code; however, empirically, this fixes an issue encountered simulating the code.