wasmtime panics when dealing with very large functions when optimizations are enabled.

[plusvic]

When I try to instantiate a WASM module that contains a very large function, and cranelift is configure to use optimizations (wasmtime::OptLevel::Speed or wasmtime::OptLevel::SpeedAndSize), it panics with:

thread '<unnamed>' panicked at /Users/vmalvarez/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/cranelift-codegen-0.123.2/src/ir/instructions.rs:228:9:
assertion failed: payload < (1 << 30)
stack backtrace:
   0:        0x105ae8298 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::hc62d1c602f32d045
   1:        0x105b06898 - core::fmt::write::hec54c1d5587662ba
   2:        0x105ae55c4 - std::io::Write::write_fmt::h32cb3f1ee5943fae
   3:        0x105ae814c - std::sys::backtrace::BacktraceLock::print::hbdf74b1541f6a1ff
   4:        0x105ae9914 - std::panicking::default_hook::{{closure}}::h5448a63c4ecd0e4e
   5:        0x105ae976c - std::panicking::default_hook::ha395121f3118f99a
   6:        0x104cca9ec - yr::main::{{closure}}::hfe5d5caf9c5c3c1f
   7:        0x105aea3d8 - std::panicking::rust_panic_with_hook::h2cf6c7b76a1ec3f1
   8:        0x105ae9fa8 - std::panicking::begin_panic_handler::{{closure}}::hb6df43c194981807
   9:        0x105ae8750 - std::sys::backtrace::__rust_end_short_backtrace::h870816de405e4980
  10:        0x105ae9cac - __rustc[e402ec7dbc433fa7]::rust_begin_unwind
  11:        0x105b84214 - core::panicking::panic_fmt::hae8dacf72a638e20
  12:        0x105b84284 - core::panicking::panic::hc324204614143dd3
  13:        0x1056ee7fc - cranelift_codegen::ir::instructions::InstructionData::map_values::h0278140030621a4a
  14:        0x1056fd830 - cranelift_codegen::egraph::EgraphPass::run::h63605c10fdb90cc5
  15:        0x1056a35bc - cranelift_codegen::context::Context::optimize::h4483eab5301b4a42
  16:        0x1056a2f60 - cranelift_codegen::context::Context::compile_stencil::ha8e37d40161c2624
  17:        0x1056a3910 - cranelift_codegen::context::Context::compile::h81a4bb0e1cd3db9e
  18:        0x10543dbec - wasmtime_internal_cranelift::compiler::FunctionCompiler::finish_with_info::hc96d5e0ca4268141
  19:        0x10543c7cc - <wasmtime_internal_cranelift::compiler::Compiler as wasmtime_environ::compile::InliningCompiler>::finish_compiling::h7532ff7544c0367b

If I disable optimizations (with wasmtime::OptLevel::None), the panic disappears and I get this error from wasmtime::Module::from_binary:

Compilation error: Code for function is too large

My expectation was that wasmtime returns an error when you try to instantiate a module that contains very large functions, no matter the optimization level you choose for cranelift.

I'm attaching WASM module in binary form that triggers this issue.

Versions and Environment

Wasmtime version or commit: 36.0.2

Operating system: Linux, macOS

Architecture: x86_64, aarch64

large.wasm.zip

[crowforkotlin]

The same problem occurs when using Kotlin/WASI to generate WebAssembly (Wasm) output if the resulting file size is too large.

[cfallin]

@crowforkotlin do you have a reproducer?

I am going to close this issue now because the large.wasm posted above now correctly fails (per the standard Wasm size limits) with

$ target/release/wasmtime compile large.wasm
Error: failed to parse WebAssembly module

Caused by:
    function body size count exceeds limit of 7654321 (at offset 0x2306)

If you have a Wasm that fails to compile via a panic rather than a proper error (as above) on the latest main, @crowforkotlin, please feel free to post a new issue!