wasmtime / issue #11682 wasmtime panics when dealing with... · git-wasmtime

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](https://github.com/user-attachments/files/22270986/large.wasm.zip)

~~~

Stream: git-wasmtime

Topic: wasmtime / issue #11682 wasmtime panics when dealing with...

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