verilog - "Memory index truncation"是什么意思？

Question

我正在尝试实现如下内存模型，但我收到了这些警告消息:

assign Data = (!CS && !OE) ? Mem[Address] : {WordSize{1'bz}};
                                       |
ncelab: *W,BIGWIX (./sram.v,16|39): Memory index truncation.  
    Mem[Address] = Data;
              |
ncelab: *W,BIGWIX (./sram.v,20|14): Memory index truncation.

这是我的代码:

// RAM Model
//


module sram (Address, Data, CS, WE, OE);

parameter AddressSize = 2592;
parameter WordSize = 32;

input [AddressSize-1:0] Address;
inout [WordSize-1:0] Data;
input CS, WE, OE;

reg [WordSize-1:0] Mem [0:(1<<AddressSize)-1];

assign Data = (!CS && !OE) ? Mem[Address] : {WordSize{1'bz}};

always @(CS or WE)
  if (!CS && !WE)
    Mem[Address] = Data;

always @(WE or OE)
  if (!WE && !OE)
    $display("Operational error in RamChip: OE and WE both active");

endmodule

“内存索引截断”是什么意思？

Answer 1

您可以使用 nchelp 获得有关任何 Cadence Incisive 警告的更详细帮助:

nchelp ncelab BIGWIX
ncelab/BIGWIX =
    A memory is being indexed. The index expression has a width
    greater than a machine word, which is typically 32 bits.
    Only 32 bits are used. This truncation may result in
    undesired behavior.

正如评论中提到的，您可能不希望地址输入信号为 2592 位宽，也不希望您的内存具有 (1<<2592) 个位置。