From a5e569245b841df3516060b0455f6d723d35d68a Mon Sep 17 00:00:00 2001 From: David Harris Date: Fri, 24 Mar 2023 09:01:07 -0700 Subject: [PATCH] Shifter capitalization --- src/ieu/shifter.sv | 42 +++++++++++++++++++++--------------------- 1 file changed, 21 insertions(+), 21 deletions(-) diff --git a/src/ieu/shifter.sv b/src/ieu/shifter.sv index 8dbdf88e..bdb40022 100644 --- a/src/ieu/shifter.sv +++ b/src/ieu/shifter.sv @@ -35,8 +35,8 @@ module shifter ( input logic Right, Rotate, W64, SubArith, // Shift right, rotate, W64-type operation, arithmetic shift output logic [`XLEN-1:0] Y); // Shifted result - logic [2*`XLEN-2:0] z, zshift; // Input to funnel shifter, shifted amount before truncated to 32 or 64 bits - logic [`LOG_XLEN-1:0] amttrunc, Offset; // Shift amount adjusted for RV64, right-shift amount + logic [2*`XLEN-2:0] Z, ZShift; // Input to funnel shifter, shifted amount before truncated to 32 or 64 bits + logic [`LOG_XLEN-1:0] TruncAmt, Offset; // Shift amount adjusted for RV64, right-shift amount logic Sign; // Sign bit for sign extension assign Sign = A[`XLEN-1] & SubArith; // sign bit for sign extension @@ -45,45 +45,45 @@ module shifter ( if (`XLEN==32) begin // rv32 with rotates always_comb // funnel mux case({Right, Rotate}) - 2'b00: z = {A[31:0], 31'b0}; - 2'b01: z = {A[31:0], A[31:1]}; - 2'b10: z = {{31{Sign}}, A[31:0]}; - 2'b11: z = {A[30:0], A}; + 2'b00: Z = {A[31:0], 31'b0}; + 2'b01: Z = {A[31:0], A[31:1]}; + 2'b10: Z = {{31{Sign}}, A[31:0]}; + 2'b11: Z = {A[30:0], A}; endcase - assign amttrunc = Amt; // shift amount + assign TruncAmt = Amt; // shift amount end else begin // rv64 with rotates // shifter rotate source select mux logic [`XLEN-1:0] RotA; // rotate source mux2 #(`XLEN) rotmux(A, {A[31:0], A[31:0]}, W64, RotA); // W64 rotatons always_comb // funnel mux case ({Right, Rotate}) - 2'b00: z = {A[63:0],{63'b0}}; - 2'b01: z = {RotA, RotA[63:1]}; - 2'b10: z = {{63{Sign}}, A[63:0]}; - 2'b11: z = {RotA[62:0], RotA}; + 2'b00: Z = {A[63:0],{63'b0}}; + 2'b01: Z = {RotA, RotA[63:1]}; + 2'b10: Z = {{63{Sign}}, A[63:0]}; + 2'b11: Z = {RotA[62:0], RotA}; endcase - assign amttrunc = W64 ? {1'b0, Amt[4:0]} : Amt; // 32- or 64-bit shift + assign TruncAmt = W64 ? {1'b0, Amt[4:0]} : Amt; // 32- or 64-bit shift end end else begin: norotfunnel if (`XLEN==32) begin:shifter // RV32 always_comb // funnel mux - if (Right) z = {{31{Sign}}, A[31:0]}; - else z = {A[31:0], 31'b0}; - assign amttrunc = Amt; // shift amount + if (Right) Z = {{31{Sign}}, A[31:0]}; + else Z = {A[31:0], 31'b0}; + assign TruncAmt = Amt; // shift amount end else begin:shifter // RV64 always_comb // funnel mux - if (Right) z = {{63{Sign}}, A[63:0]}; - else z = {A[63:0], {63'b0}}; - assign amttrunc = W64 ? {1'b0, Amt[4:0]} : Amt; // 32- or 64-bit shift + if (Right) Z = {{63{Sign}}, A[63:0]}; + else Z = {A[63:0], {63'b0}}; + assign TruncAmt = W64 ? {1'b0, Amt[4:0]} : Amt; // 32- or 64-bit shift end end // Opposite offset for right shifts - assign Offset = Right ? amttrunc : ~amttrunc; + assign Offset = Right ? TruncAmt : ~TruncAmt; // Funnel operation - assign zshift = z >> Offset; - assign Y = zshift[`XLEN-1:0]; + assign ZShift = Z >> Offset; + assign Y = ZShift[`XLEN-1:0]; endmodule