🟡 [Medium] Performance EVM: Memory size limited to u24 (16MB)

[roninjin10]

Summary

The memory module uses u24 for size parameters, limiting EVM memory to 16MB. While sufficient for most cases, this could be surprising and limiting.

Location

src/memory/memory.zig:100-107

Current Code

pub inline fn ensure_capacity(self: *Self, allocator: std.mem.Allocator, new_size: u24) !void {
    // ...
    if (required_total > MEMORY_LIMIT) {
        @branchHint(.unlikely);
        return MemoryError.MemoryOverflow;
    }

Analysis

• u24 max value: 16,777,215 bytes (~16MB)
• EVM has no hard memory limit (only gas-bounded)
• Some edge cases or tests might require more
• Performance EVM's FrameConfig uses memory_limit: u32 = 16 * 1024 * 1024 (16MB default)

Impact

• Contracts requiring >16MB memory will fail unexpectedly
• May cause issues with certain test cases
• Inconsistent with EVM specification (no hard limit)

Recommended Fix

Consider using u32 for size parameters:

pub inline fn ensure_capacity(self: *Self, allocator: std.mem.Allocator, new_size: u32) !void {

Or document the limitation clearly if intentional for performance.

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Note: This issue was created by Claude AI assistant during code review, not @roninjin10 or @fucory