diff --git a/src/ieu/alu.sv b/src/ieu/alu.sv
index 15a19f55..97cda872 100644
--- a/src/ieu/alu.sv
+++ b/src/ieu/alu.sv
@@ -57,14 +57,14 @@ module alu #(parameter WIDTH=32) (
   // Addition
   if (`ZBB_SUPPORTED) 
     always_comb begin
-      case({Funct7, Funct3})
-        10'b0010000_010: CondShiftA = {A[WIDTH-1:1], {1'b0}};      //sh1add
-        10'b0010000_100: CondShiftA = {A[WIDTH-1:2], {2'b00}};     //sh2add
-        10'b0010000_110: CondShiftA = {A[WIDTH-1:3], {3'b000}};    //sh3add
-        10'b0000100_000: CondShiftA = {{32{1'b0}}, A[31:0]};       //add.uw
-        10'b0010000_010: CondShiftA = {{31{1'b0}},A[31:0], {1'b0}}; //sh1add.uw
-        10'b0010000_100: CondShiftA = {{30{1'b0}},A[31:0], {2'b0}}; //sh2add.uw
-        10'b0010000_110: CondShiftA = {{29{1'b0}},A[31:0], {3'b0}}; //sh3add.uw
+      case({Funct7, Funct3, W64})
+        11'b0010000_010_0: CondShiftA = {A[WIDTH-1:1], {1'b0}};      //sh1add
+        11'b0010000_100_0: CondShiftA = {A[WIDTH-1:2], {2'b00}};     //sh2add
+        11'b0010000_110_0: CondShiftA = {A[WIDTH-1:3], {3'b000}};    //sh3add
+        11'b0000100_000_1: CondShiftA = {{32{1'b0}}, A[31:0]};       //add.uw
+        11'b0010000_010_1: CondShiftA = {{31{1'b0}},A[31:0], {1'b0}}; //sh1add.uw
+        11'b0010000_100_1: CondShiftA = {{30{1'b0}},A[31:0], {2'b0}}; //sh2add.uw
+        11'b0010000_110_1: CondShiftA = {{29{1'b0}},A[31:0], {3'b0}}; //sh3add.uw
         default: CondShiftA = A;
       endcase
 
@@ -76,13 +76,9 @@ module alu #(parameter WIDTH=32) (
       endcase
 
       casez ({Funct7, Funct3})
-        10'b0110000_101: Rotate = 1'b1;
         10'b011000?_101: Rotate = 1'b1;
         10'b000010?_001: Rotate = 1'b0;
         10'b0110000_001: Rotate = 1'b1;
-        10'b0110000_101: Rotate = 1'b1;
-        10'b0110000_001: Rotate = 1'b1;
-        10'b0110000_101: Rotate = 1'b1;
         default:         Rotate = 1'b0;
       endcase
     end
@@ -126,12 +122,12 @@ module alu #(parameter WIDTH=32) (
     endcase
 
   if (`ZBS_SUPPORTED) 
-    zbs zbs(.A, .B, .Funct7, .Funct3, .ZBSResult);
+    zbs #(WIDTH) zbs(.A, .B, .Funct7, .Funct3, .ZBSResult);
   else assign ZBSResult = 0; 
   
 
   if (`ZBB_SUPPORTED) 
-    zbb zbb(.A, .B, .Funct3, .Funct7, .W64, .ZBBResult);
+    zbb #(WIDTH) zbb(.A, .B, .Funct3, .Funct7, .W64, .ZBBResult);
   else assign ZBBResult = 0; 
 
   // Support RV64I W-type addw/subw/addiw/shifts that discard upper 32 bits and sign-extend 32-bit result to 64 bits
diff --git a/src/ieu/bmu/popcnt.sv b/src/ieu/bmu/popcnt.sv
index 456e0774..c82476a6 100644
--- a/src/ieu/bmu/popcnt.sv
+++ b/src/ieu/bmu/popcnt.sv
@@ -31,20 +31,14 @@ module popcnt #(parameter WIDTH = 32) (
 
   logic [$clog2(WIDTH):0] sum; 
   
-  /*always_comb begin
+  always_comb begin
     sum = 0;
     for (int i=0;i<WIDTH;i++) begin:loop
-      sum = sum + num[i];
+      sum = (num[i]) ? sum + 1 : sum;
     end
   end
-  */
 
-  genvar i;
-  for (i=0;i<WIDTH;i++) begin:loop
-    assign sum = sum + {{5'b0},num[i]};
-  end
-
-  assign PopCnt = sum;
+  assign PopCnt = sum[$clog2(WIDTH):0];
 
   
 endmodule
diff --git a/src/ieu/bmu/zbb.sv b/src/ieu/bmu/zbb.sv
index e469fcef..296d15d5 100644
--- a/src/ieu/bmu/zbb.sv
+++ b/src/ieu/bmu/zbb.sv
@@ -52,9 +52,9 @@ module zbb #(parameter WIDTH=32) (
   logic [WIDTH-1:0] sextbResult;         // sign extend byte result
   logic [WIDTH-1:0] zexthResult;         // zero extend halfword result 
 
-  cnt cnt(.A(A), .B(B), .W64(W64), .czResult(czResult), .cpopResult(cpopResult));
-  byteUnit bu(.A(A), .OrcBResult(OrcBResult), .Rev8Result(Rev8Result));
-  ext ext(.A(A), .sexthResult(sexthResult), .sextbResult(sextbResult), .zexthResult(zexthResult));
+  cnt #(WIDTH) cnt(.A(A), .B(B), .W64(W64), .czResult(czResult), .cpopResult(cpopResult));
+  byteUnit #(WIDTH) bu(.A(A), .OrcBResult(OrcBResult), .Rev8Result(Rev8Result));
+  ext #(WIDTH) ext(.A(A), .sexthResult(sexthResult), .sextbResult(sextbResult), .zexthResult(zexthResult));
 
   //can replace with structural mux by looking at bit 4 in rs2 field
   always_comb begin 
@@ -68,6 +68,7 @@ module zbb #(parameter WIDTH=32) (
       15'b0000100_100_00000: ZBBResult = zexthResult; 
       15'b0110000_001_00100: ZBBResult = sextbResult;
       15'b0110000_001_00101: ZBBResult = sexthResult;
+      default: ZBBResult = {(WIDTH){1'b0}};
       endcase
   end