diff options
8 files changed, 189 insertions, 4 deletions
diff --git a/src/librustc_codegen_llvm/attributes.rs b/src/librustc_codegen_llvm/attributes.rs index 5479a1f3144..3f2a51b45bd 100644 --- a/src/librustc_codegen_llvm/attributes.rs +++ b/src/librustc_codegen_llvm/attributes.rs @@ -344,6 +344,17 @@ pub fn from_fn_attrs( const_cstr!("wasm-import-module"), &module, ); + + let name = codegen_fn_attrs.link_name.unwrap_or_else(|| { + cx.tcx.item_name(instance.def_id()) + }); + let name = CString::new(&name.as_str()[..]).unwrap(); + llvm::AddFunctionAttrStringValue( + llfn, + llvm::AttributePlace::Function, + const_cstr!("wasm-import-name"), + &name, + ); } } } diff --git a/src/librustc_codegen_utils/symbol_names.rs b/src/librustc_codegen_utils/symbol_names.rs index c52c6cfa83c..922964ee45f 100644 --- a/src/librustc_codegen_utils/symbol_names.rs +++ b/src/librustc_codegen_utils/symbol_names.rs @@ -142,12 +142,32 @@ fn symbol_name(tcx: TyCtxt<'tcx>, instance: Instance<'tcx>) -> Symbol { }; let attrs = tcx.codegen_fn_attrs(def_id); + + // Foreign items by default use no mangling for their symbol name. There's a + // few exceptions to this rule though: + // + // * This can be overridden with the `#[link_name]` attribute + // + // * On the wasm32 targets there is a bug (or feature) in LLD [1] where the + // same-named symbol when imported from different wasm modules will get + // hooked up incorectly. As a result foreign symbols, on the wasm target, + // with a wasm import module, get mangled. Additionally our codegen will + // deduplicate symbols based purely on the symbol name, but for wasm this + // isn't quite right because the same-named symbol on wasm can come from + // different modules. For these reasons if `#[link(wasm_import_module)]` + // is present we mangle everything on wasm because the demangled form will + // show up in the `wasm-import-name` custom attribute in LLVM IR. + // + // [1]: https://bugs.llvm.org/show_bug.cgi?id=44316 if is_foreign { - if let Some(name) = attrs.link_name { - return name; + if tcx.sess.target.target.arch != "wasm32" || + !tcx.wasm_import_module_map(def_id.krate).contains_key(&def_id) + { + if let Some(name) = attrs.link_name { + return name; + } + return tcx.item_name(def_id); } - // Don't mangle foreign items. - return tcx.item_name(def_id); } if let Some(name) = attrs.export_name { diff --git a/src/test/run-make/wasm-symbols-different-module/Makefile b/src/test/run-make/wasm-symbols-different-module/Makefile new file mode 100644 index 00000000000..bb6a5d3c9d2 --- /dev/null +++ b/src/test/run-make/wasm-symbols-different-module/Makefile @@ -0,0 +1,28 @@ +-include ../../run-make-fulldeps/tools.mk + +# only-wasm32-bare + +all: + $(RUSTC) foo.rs --target wasm32-unknown-unknown + $(NODE) verify-imports.js $(TMPDIR)/foo.wasm a/foo b/foo + $(RUSTC) foo.rs --target wasm32-unknown-unknown -C lto + $(NODE) verify-imports.js $(TMPDIR)/foo.wasm a/foo b/foo + $(RUSTC) foo.rs --target wasm32-unknown-unknown -O + $(NODE) verify-imports.js $(TMPDIR)/foo.wasm a/foo b/foo + $(RUSTC) foo.rs --target wasm32-unknown-unknown -O -C lto + $(NODE) verify-imports.js $(TMPDIR)/foo.wasm a/foo b/foo + + $(RUSTC) bar.rs --target wasm32-unknown-unknown + $(NODE) verify-imports.js $(TMPDIR)/bar.wasm m1/f m1/g m2/f + $(RUSTC) bar.rs --target wasm32-unknown-unknown -C lto + $(NODE) verify-imports.js $(TMPDIR)/bar.wasm m1/f m1/g m2/f + $(RUSTC) bar.rs --target wasm32-unknown-unknown -O + $(NODE) verify-imports.js $(TMPDIR)/bar.wasm m1/f m1/g m2/f + $(RUSTC) bar.rs --target wasm32-unknown-unknown -O -C lto + $(NODE) verify-imports.js $(TMPDIR)/bar.wasm m1/f m1/g m2/f + + $(RUSTC) baz.rs --target wasm32-unknown-unknown + $(NODE) verify-imports.js $(TMPDIR)/baz.wasm sqlite/allocate sqlite/deallocate + + $(RUSTC) log.rs --target wasm32-unknown-unknown + $(NODE) verify-imports.js $(TMPDIR)/log.wasm test/log diff --git a/src/test/run-make/wasm-symbols-different-module/bar.rs b/src/test/run-make/wasm-symbols-different-module/bar.rs new file mode 100644 index 00000000000..7567060d781 --- /dev/null +++ b/src/test/run-make/wasm-symbols-different-module/bar.rs @@ -0,0 +1,33 @@ +//! Issue #50021 + +#![crate_type = "cdylib"] + +mod m1 { + #[link(wasm_import_module = "m1")] + extern "C" { + pub fn f(); + } + #[link(wasm_import_module = "m1")] + extern "C" { + pub fn g(); + } +} + +mod m2 { + #[link(wasm_import_module = "m2")] + extern "C" { + pub fn f(_: i32); + } +} + +#[no_mangle] +pub unsafe fn run() { + m1::f(); + m1::g(); + + // In generated code, expected: + // (import "m2" "f" (func $f (param i32))) + // but got: + // (import "m1" "f" (func $f (param i32))) + m2::f(0); +} diff --git a/src/test/run-make/wasm-symbols-different-module/baz.rs b/src/test/run-make/wasm-symbols-different-module/baz.rs new file mode 100644 index 00000000000..fbb78619bb8 --- /dev/null +++ b/src/test/run-make/wasm-symbols-different-module/baz.rs @@ -0,0 +1,22 @@ +//! Issue #63562 + +#![crate_type = "cdylib"] + +mod foo { + #[link(wasm_import_module = "sqlite")] + extern "C" { + pub fn allocate(size: usize) -> i32; + pub fn deallocate(ptr: i32, size: usize); + } +} + +#[no_mangle] +pub extern "C" fn allocate() { + unsafe { + foo::allocate(1); + foo::deallocate(1, 2); + } +} + +#[no_mangle] +pub extern "C" fn deallocate() {} diff --git a/src/test/run-make/wasm-symbols-different-module/foo.rs b/src/test/run-make/wasm-symbols-different-module/foo.rs new file mode 100644 index 00000000000..a4ba7e714cc --- /dev/null +++ b/src/test/run-make/wasm-symbols-different-module/foo.rs @@ -0,0 +1,23 @@ +#![crate_type = "cdylib"] + +mod a { + #[link(wasm_import_module = "a")] + extern "C" { + pub fn foo(); + } +} + +mod b { + #[link(wasm_import_module = "b")] + extern "C" { + pub fn foo(); + } +} + +#[no_mangle] +pub fn start() { + unsafe { + a::foo(); + b::foo(); + } +} diff --git a/src/test/run-make/wasm-symbols-different-module/log.rs b/src/test/run-make/wasm-symbols-different-module/log.rs new file mode 100644 index 00000000000..ea3e0b4b2be --- /dev/null +++ b/src/test/run-make/wasm-symbols-different-module/log.rs @@ -0,0 +1,16 @@ +//! Issue #56309 + +#![crate_type = "cdylib"] + +#[link(wasm_import_module = "test")] +extern "C" { + fn log(message_data: u32, message_size: u32); +} + +#[no_mangle] +pub fn main() { + let message = "Hello, world!"; + unsafe { + log(message.as_ptr() as u32, message.len() as u32); + } +} diff --git a/src/test/run-make/wasm-symbols-different-module/verify-imports.js b/src/test/run-make/wasm-symbols-different-module/verify-imports.js new file mode 100644 index 00000000000..7e9f90cf8bd --- /dev/null +++ b/src/test/run-make/wasm-symbols-different-module/verify-imports.js @@ -0,0 +1,32 @@ +const fs = require('fs'); +const process = require('process'); +const assert = require('assert'); +const buffer = fs.readFileSync(process.argv[2]); + +let m = new WebAssembly.Module(buffer); +let list = WebAssembly.Module.imports(m); +console.log('imports', list); +if (list.length !== process.argv.length - 3) + throw new Error("wrong number of imports") + +const imports = new Map(); +for (let i = 3; i < process.argv.length; i++) { + const [module, name] = process.argv[i].split('/'); + if (!imports.has(module)) + imports.set(module, new Map()); + imports.get(module).set(name, true); +} + +for (let i of list) { + if (imports.get(i.module) === undefined || imports.get(i.module).get(i.name) === undefined) + throw new Error(`didn't find import of ${i.module}::${i.name}`); + imports.get(i.module).delete(i.name); + + if (imports.get(i.module).size === 0) + imports.delete(i.module); +} + +console.log(imports); +if (imports.size !== 0) { + throw new Error('extra imports'); +} |