Split the runtime and execution code into separate crates.

lib/obj/src/emit_module.rs

@@ -0,0 +1,117 @@
+use cretonne::Context;
+use cretonne::settings;
+use cretonne::isa::TargetIsa;
+use cretonne::verify_function;
+use cretonne::verifier;
+use cretonne::settings::Configurable;
+use cretonne::result::CtonError;
+use cretonne::ir::entities::AnyEntity;
+use cretonne::ir::{self, Ebb, FuncRef, JumpTable, Function};
+use cretonne::binemit::{RelocSink, Reloc, CodeOffset};
+use cton_wasm::TranslationResult;
+use std::fmt::Write;
+use faerie::Artifact;
+use wasmstandalone_runtime;
+
+type RelocRef = u16;
+
+// Implementation of a relocation sink that just saves all the information for later
+struct FaerieRelocSink {
+    ebbs: Vec<(RelocRef, Ebb, CodeOffset)>,
+    funcs: Vec<(RelocRef, FuncRef, CodeOffset)>,
+    jts: Vec<(RelocRef, JumpTable, CodeOffset)>,
+}
+
+impl RelocSink for FaerieRelocSink {
+    fn reloc_ebb(&mut self, offset: CodeOffset, reloc: Reloc, ebb: Ebb) {
+        self.ebbs.push((reloc.0, ebb, offset));
+    }
+    fn reloc_func(&mut self, offset: CodeOffset, reloc: Reloc, func: FuncRef) {
+        self.funcs.push((reloc.0, func, offset));
+    }
+    fn reloc_jt(&mut self, offset: CodeOffset, reloc: Reloc, jt: JumpTable) {
+        self.jts.push((reloc.0, jt, offset));
+    }
+}
+
+impl FaerieRelocSink {
+    fn new() -> FaerieRelocSink {
+        FaerieRelocSink {
+            ebbs: Vec::new(),
+            funcs: Vec::new(),
+            jts: Vec::new(),
+        }
+    }
+}
+
+/// Emits a module that has been emitted with the `WasmRuntime` runtime
+/// implementation to a native object file.
+pub fn emit_module(
+    trans_result: &TranslationResult,
+    obj: &mut Artifact,
+    isa: &TargetIsa,
+    runtime: &wasmstandalone_runtime::Runtime,
+) -> Result<(), String> {
+    debug_assert!(
+        trans_result.start_index.is_none() ||
+            trans_result.start_index.unwrap() >= runtime.imported_funcs.len(),
+        "imported start functions not supported yet"
+    );
+
+    let mut shared_builder = settings::builder();
+    shared_builder.enable("enable_verifier").expect(
+        "Missing enable_verifier setting",
+    );
+
+    for function in &trans_result.functions {
+        let mut context = Context::new();
+        verify_function(function, isa).unwrap();
+        context.func = function.clone(); // TODO: Avoid this clone.
+        let code_size = context.compile(&*isa).map_err(|e| {
+            pretty_error(&context.func, Some(isa), e)
+        })? as usize;
+        if code_size == 0 {
+            return Err(String::from("no code generated by Cretonne"));
+        }
+        let mut code_buf: Vec<u8> = Vec::with_capacity(code_size);
+        code_buf.resize(code_size, 0);
+        let mut relocsink = FaerieRelocSink::new();
+        context.emit_to_memory(code_buf.as_mut_ptr(), &mut relocsink, &*isa);
+
+        // FIXME: get the real linkage name of the function
+        obj.add_code("the_function_name", code_buf);
+
+        assert!(relocsink.jts.is_empty(), "jump tables not yet implemented");
+        assert!(relocsink.ebbs.is_empty(), "ebb relocs not yet implemented");
+        assert!(
+            relocsink.funcs.is_empty(),
+            "function relocs not yet implemented"
+        );
+
+        // FIXME: handle imports
+    }
+
+    Ok(())
+}
+
+/// Pretty-print a verifier error.
+fn pretty_verifier_error(func: &Function, isa: Option<&TargetIsa>, err: verifier::Error) -> String {
+    let mut msg = err.to_string();
+    match err.location {
+        AnyEntity::Inst(inst) => {
+            write!(msg, "\n{}: {}\n\n", inst, func.dfg.display_inst(inst, isa)).unwrap()
+        }
+        _ => msg.push('\n'),
+    }
+    write!(msg, "{}", func.display(isa)).unwrap();
+    msg
+}
+
+/// Pretty-print a Cretonne error.
+fn pretty_error(func: &ir::Function, isa: Option<&TargetIsa>, err: CtonError) -> String {
+    if let CtonError::Verifier(e) = err {
+        pretty_verifier_error(func, isa, e)
+    } else {
+        err.to_string()
+    }
+}

lib/obj/src/lib.rs

@@ -0,0 +1,8 @@
+extern crate cretonne;
+extern crate cton_wasm;
+extern crate faerie;
+extern crate wasmstandalone_runtime;
+
+mod emit_module;
+
+pub use emit_module::emit_module;