profiling optimizations

minor updates

hw/rtl/core/VX_dispatch.sv

@@ -174,30 +174,38 @@ module VX_dispatch import VX_gpu_pkg::*; #(
                                    || (sfu_operands_if[i].ready && (operands_if[i].data.ex_type == `EX_SFU));
     end
 
-`ifdef PERF_ENABLE
-    reg [`NUM_EX_UNITS-1:0][`PERF_CTR_BITS-1:0] perf_stalls_n, perf_stalls_r;
-    wire [`ISSUE_WIDTH-1:0] operands_stall;
-    wire [`ISSUE_WIDTH-1:0][`EX_BITS-1:0] operands_ex_type;
+`ifdef PERF_ENABLE    
+    wire [`NUM_EX_UNITS-1:0] perf_unit_stalls_per_cycle, perf_unit_stalls_per_cycle_r;
+    reg [`ISSUE_WIDTH-1:0][`NUM_EX_UNITS-1:0] perf_issue_unit_stalls_per_cycle;
+    reg [`NUM_EX_UNITS-1:0][`PERF_CTR_BITS-1:0] perf_stalls_r;
 
     for (genvar i=0; i < `ISSUE_WIDTH; ++i) begin
-        assign operands_stall[i] = operands_if[i].valid && ~operands_if[i].ready;
-        assign operands_ex_type[i] = operands_if[i].data.ex_type;
-    end
-
-    always @(*) begin
-        perf_stalls_n = perf_stalls_r;
-        for (integer i=0; i < `ISSUE_WIDTH; ++i) begin
-            if (operands_stall[i]) begin
-                perf_stalls_n[operands_ex_type[i]] += `PERF_CTR_BITS'(1);
+        always @(*) begin        
+            perf_issue_unit_stalls_per_cycle[i] = '0;
+            if (operands_if[i].valid && ~operands_if[i].ready) begin
+                perf_issue_unit_stalls_per_cycle[i][operands_if[i].data.ex_type] = 1;
             end
         end
     end
 
-    always @(posedge clk) begin
-        if (reset) begin
-            perf_stalls_r <= '0;
-        end else begin
-            perf_stalls_r <= perf_stalls_n;
+    VX_reduce #(
+        .DATAW_IN (`NUM_EX_UNITS),
+        .N  (`ISSUE_WIDTH),
+        .OP ("|")
+    ) reduce (
+        .data_in (perf_issue_unit_stalls_per_cycle),
+        .data_out (perf_unit_stalls_per_cycle)
+    );
+
+    `BUFFER(perf_unit_stalls_per_cycle_r, perf_unit_stalls_per_cycle);
+
+    for (genvar i = 0; i < `NUM_EX_UNITS; ++i) begin
+        always @(posedge clk) begin
+            if (reset) begin
+                perf_stalls_r[i] <= '0;
+            end else begin
+                perf_stalls_r[i] <= perf_stalls_r[i] + `PERF_CTR_BITS'(perf_unit_stalls_per_cycle_r[i]);
+            end
         end
     end