Rollup merge of #58057 - michaelwoerister:stabilize-xlto, r=alexcrichton
Stabilize linker-plugin based LTO (aka cross-language LTO) This PR stabilizes [linker plugin based LTO](https://github.com/rust-lang/rust/issues/49879), also known as "cross-language LTO" because it allows for doing inlining and other optimizations across language boundaries in mixed Rust/C/C++ projects. As described in the tracking issue, it works by making `rustc` emit LLVM bitcode instead of machine code, the same as `clang` does. A linker with the proper plugin (like LLD) can then run (Thin)LTO across all modules. The feature has been implemented over a number of pull requests and there are various [codegen](https://github.com/rust-lang/rust/blob/master/src/test/codegen/no-dllimport-w-cross-lang-lto.rs) and [run](https://github.com/rust-lang/rust/tree/master/src/test/run-make-fulldeps/cross-lang-lto-clang)-[make](https://github.com/rust-lang/rust/tree/master/src/test/run-make-fulldeps/cross-lang-lto-upstream-rlibs) [tests](https://github.com/rust-lang/rust/tree/master/src/test/run-make-fulldeps/cross-lang-lto) that make sure that it keeps working. It also works for building big projects like [Firefox](https://treeherder.mozilla.org/#/jobs?repo=try&revision=2ce2d5ddcea6fbff790503eac406954e469b2f5d). The PR makes the feature available under the `-C linker-plugin-lto` flag. As discussed in the tracking issue it is not cross-language specific and also not LLD specific. `-C linker-plugin-lto` is descriptive of what it does. If someone has a better name, let me know `:)`
This commit is contained in:
Mazdak Farrokhzad
@@ -13,4 +13,5 @@
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- [Targets](targets/index.md)
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- [Built-in Targets](targets/built-in.md)
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- [Custom Targets](targets/custom.md)
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- [Linker-plugin based LTO](linker-plugin-lto.md)
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- [Contributing to `rustc`](contributing.md)
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108
src/doc/rustc/src/linker-plugin-lto.md
Normal file
108
src/doc/rustc/src/linker-plugin-lto.md
Normal file
@@ -0,0 +1,108 @@
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# Linker-plugin-LTO
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The `-C linker-plugin-lto` flag allows for deferring the LTO optimization
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to the actual linking step, which in turn allows for performing
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interprocedural optimizations across programming language boundaries if
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all the object files being linked were created by LLVM based toolchains.
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The prime example here would be linking Rust code together with
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Clang-compiled C/C++ code.
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## Usage
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There are two main cases how linker plugin based LTO can be used:
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- compiling a Rust `staticlib` that is used as a C ABI dependency
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- compiling a Rust binary where `rustc` invokes the linker
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In both cases the Rust code has to be compiled with `-C linker-plugin-lto` and
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the C/C++ code with `-flto` or `-flto=thin` so that object files are emitted
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as LLVM bitcode.
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### Rust `staticlib` as dependency in C/C++ program
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In this case the Rust compiler just has to make sure that the object files in
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the `staticlib` are in the right format. For linking, a linker with the
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LLVM plugin must be used (e.g. LLD).
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Using `rustc` directly:
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```bash
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# Compile the Rust staticlib
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rustc --crate-type=staticlib -Clinker-plugin-lto -Copt-level=2 ./lib.rs
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# Compile the C code with `-flto=thin`
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clang -c -O2 -flto=thin -o main.o ./main.c
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# Link everything, making sure that we use an appropriate linker
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clang -flto=thin -fuse-ld=lld -L . -l"name-of-your-rust-lib" -o main -O2 ./cmain.o
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```
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Using `cargo`:
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```bash
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# Compile the Rust staticlib
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RUSTFLAGS="-Clinker-plugin-lto" cargo build --release
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# Compile the C code with `-flto=thin`
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clang -c -O2 -flto=thin -o main.o ./main.c
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# Link everything, making sure that we use an appropriate linker
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clang -flto=thin -fuse-ld=lld -L . -l"name-of-your-rust-lib" -o main -O2 ./cmain.o
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```
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### C/C++ code as a dependency in Rust
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In this case the linker will be invoked by `rustc`. We again have to make sure
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that an appropriate linker is used.
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Using `rustc` directly:
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```bash
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# Compile C code with `-flto`
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clang ./clib.c -flto=thin -c -o ./clib.o -O2
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# Create a static library from the C code
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ar crus ./libxyz.a ./clib.o
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# Invoke `rustc` with the additional arguments
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rustc -Clinker-plugin-lto -L. -Copt-level=2 -Clinker=clang -Clink-arg=-fuse-ld=lld ./main.rs
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```
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Using `cargo` directly:
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```bash
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# Compile C code with `-flto`
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clang ./clib.c -flto=thin -c -o ./clib.o -O2
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# Create a static library from the C code
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ar crus ./libxyz.a ./clib.o
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# Set the linking arguments via RUSTFLAGS
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RUSTFLAGS="-Clinker-plugin-lto -Clinker=clang -Clink-arg=-fuse-ld=lld" cargo build --release
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```
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### Explicitly specifying the linker plugin to be used by `rustc`
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If one wants to use a linker other than LLD, the LLVM linker plugin has to be
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specified explicitly. Otherwise the linker cannot read the object files. The
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path to the plugin is passed as an argument to the `-Clinker-plugin-lto`
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option:
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```bash
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rustc -Clinker-plugin-lto="/path/to/LLVMgold.so" -L. -Copt-level=2 ./main.rs
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```
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## Toolchain Compatibility
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In order for this kind of LTO to work, the LLVM linker plugin must be able to
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handle the LLVM bitcode produced by both `rustc` and `clang`.
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Best results are achieved by using a `rustc` and `clang` that are based on the
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exact same version of LLVM. One can use `rustc -vV` in order to view the LLVM
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used by a given `rustc` version. Note that the version number given
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here is only an approximation as Rust sometimes uses unstable revisions of
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LLVM. However, the approximation is usually reliable.
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The following table shows known good combinations of toolchain versions.
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| | Clang 7 | Clang 8 |
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|-----------|-----------|-----------|
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| Rust 1.34 | ✗ | ✓ |
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| Rust 1.35 | ✗ | ✓(?) |
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Note that the compatibility policy for this feature might change in the future.
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@@ -96,18 +96,18 @@ pub enum LtoCli {
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}
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#[derive(Clone, PartialEq, Hash)]
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pub enum CrossLangLto {
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pub enum LinkerPluginLto {
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LinkerPlugin(PathBuf),
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LinkerPluginAuto,
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Disabled
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}
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impl CrossLangLto {
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impl LinkerPluginLto {
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pub fn enabled(&self) -> bool {
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match *self {
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CrossLangLto::LinkerPlugin(_) |
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CrossLangLto::LinkerPluginAuto => true,
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CrossLangLto::Disabled => false,
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LinkerPluginLto::LinkerPlugin(_) |
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LinkerPluginLto::LinkerPluginAuto => true,
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LinkerPluginLto::Disabled => false,
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}
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}
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}
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@@ -812,7 +812,7 @@ macro_rules! options {
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pub const parse_lto: Option<&str> =
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Some("either a boolean (`yes`, `no`, `on`, `off`, etc), `thin`, \
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`fat`, or omitted");
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pub const parse_cross_lang_lto: Option<&str> =
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pub const parse_linker_plugin_lto: Option<&str> =
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Some("either a boolean (`yes`, `no`, `on`, `off`, etc), \
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or the path to the linker plugin");
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pub const parse_merge_functions: Option<&str> =
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@@ -821,7 +821,7 @@ macro_rules! options {
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#[allow(dead_code)]
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mod $mod_set {
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use super::{$struct_name, Passes, Sanitizer, LtoCli, CrossLangLto};
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use super::{$struct_name, Passes, Sanitizer, LtoCli, LinkerPluginLto};
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use rustc_target::spec::{LinkerFlavor, MergeFunctions, PanicStrategy, RelroLevel};
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use std::path::PathBuf;
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use std::str::FromStr;
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@@ -1037,22 +1037,22 @@ macro_rules! options {
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true
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}
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fn parse_cross_lang_lto(slot: &mut CrossLangLto, v: Option<&str>) -> bool {
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fn parse_linker_plugin_lto(slot: &mut LinkerPluginLto, v: Option<&str>) -> bool {
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if v.is_some() {
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let mut bool_arg = None;
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if parse_opt_bool(&mut bool_arg, v) {
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*slot = if bool_arg.unwrap() {
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CrossLangLto::LinkerPluginAuto
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LinkerPluginLto::LinkerPluginAuto
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} else {
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CrossLangLto::Disabled
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LinkerPluginLto::Disabled
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};
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return true
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}
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}
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*slot = match v {
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None => CrossLangLto::LinkerPluginAuto,
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Some(path) => CrossLangLto::LinkerPlugin(PathBuf::from(path)),
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None => LinkerPluginLto::LinkerPluginAuto,
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Some(path) => LinkerPluginLto::LinkerPlugin(PathBuf::from(path)),
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};
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true
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}
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@@ -1145,6 +1145,10 @@ options! {CodegenOptions, CodegenSetter, basic_codegen_options,
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"allow the linker to link its default libraries"),
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linker_flavor: Option<LinkerFlavor> = (None, parse_linker_flavor, [UNTRACKED],
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"Linker flavor"),
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linker_plugin_lto: LinkerPluginLto = (LinkerPluginLto::Disabled,
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parse_linker_plugin_lto, [TRACKED],
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"generate build artifacts that are compatible with linker-based LTO."),
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}
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options! {DebuggingOptions, DebuggingSetter, basic_debugging_options,
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@@ -1383,8 +1387,6 @@ options! {DebuggingOptions, DebuggingSetter, basic_debugging_options,
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"make the current crate share its generic instantiations"),
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chalk: bool = (false, parse_bool, [TRACKED],
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"enable the experimental Chalk-based trait solving engine"),
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cross_lang_lto: CrossLangLto = (CrossLangLto::Disabled, parse_cross_lang_lto, [TRACKED],
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"generate build artifacts that are compatible with linker-based LTO."),
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no_parallel_llvm: bool = (false, parse_bool, [UNTRACKED],
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"don't run LLVM in parallel (while keeping codegen-units and ThinLTO)"),
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no_leak_check: bool = (false, parse_bool, [UNTRACKED],
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@@ -2440,7 +2442,7 @@ mod dep_tracking {
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use std::path::PathBuf;
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use std::collections::hash_map::DefaultHasher;
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use super::{CrateType, DebugInfo, ErrorOutputType, OptLevel, OutputTypes,
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Passes, Sanitizer, LtoCli, CrossLangLto};
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Passes, Sanitizer, LtoCli, LinkerPluginLto};
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use syntax::feature_gate::UnstableFeatures;
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use rustc_target::spec::{MergeFunctions, PanicStrategy, RelroLevel, TargetTriple};
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use syntax::edition::Edition;
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@@ -2507,7 +2509,7 @@ mod dep_tracking {
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impl_dep_tracking_hash_via_hash!(Option<Sanitizer>);
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impl_dep_tracking_hash_via_hash!(TargetTriple);
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impl_dep_tracking_hash_via_hash!(Edition);
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impl_dep_tracking_hash_via_hash!(CrossLangLto);
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impl_dep_tracking_hash_via_hash!(LinkerPluginLto);
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impl_dep_tracking_hash_for_sortable_vec_of!(String);
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impl_dep_tracking_hash_for_sortable_vec_of!(PathBuf);
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@@ -2572,7 +2574,7 @@ mod tests {
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use crate::lint;
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use crate::middle::cstore;
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use crate::session::config::{build_configuration, build_session_options_and_crate_config};
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use crate::session::config::{LtoCli, CrossLangLto};
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use crate::session::config::{LtoCli, LinkerPluginLto};
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use crate::session::build_session;
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use crate::session::search_paths::SearchPath;
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use std::collections::{BTreeMap, BTreeSet};
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@@ -3105,6 +3107,10 @@ mod tests {
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opts = reference.clone();
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opts.cg.panic = Some(PanicStrategy::Abort);
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assert!(reference.dep_tracking_hash() != opts.dep_tracking_hash());
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opts = reference.clone();
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opts.cg.linker_plugin_lto = LinkerPluginLto::LinkerPluginAuto;
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assert!(reference.dep_tracking_hash() != opts.dep_tracking_hash());
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}
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#[test]
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@@ -3231,10 +3237,6 @@ mod tests {
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opts.debugging_opts.relro_level = Some(RelroLevel::Full);
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assert!(reference.dep_tracking_hash() != opts.dep_tracking_hash());
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opts = reference.clone();
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opts.debugging_opts.cross_lang_lto = CrossLangLto::LinkerPluginAuto;
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assert!(reference.dep_tracking_hash() != opts.dep_tracking_hash());
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opts = reference.clone();
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opts.debugging_opts.merge_functions = Some(MergeFunctions::Disabled);
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assert!(reference.dep_tracking_hash() != opts.dep_tracking_hash());
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@@ -1267,7 +1267,7 @@ fn validate_commandline_args_with_session_available(sess: &Session) {
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// bitcode during ThinLTO. Therefore we disallow dynamic linking on MSVC
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// when compiling for LLD ThinLTO. This way we can validly just not generate
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// the `dllimport` attributes and `__imp_` symbols in that case.
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if sess.opts.debugging_opts.cross_lang_lto.enabled() &&
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if sess.opts.cg.linker_plugin_lto.enabled() &&
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sess.opts.cg.prefer_dynamic &&
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sess.target.target.options.is_like_msvc {
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sess.err("Linker plugin based LTO is not supported together with \
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@@ -857,7 +857,7 @@ fn link_args(cmd: &mut dyn Linker,
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codegen_results: &CodegenResults) {
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// Linker plugins should be specified early in the list of arguments
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cmd.cross_lang_lto();
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cmd.linker_plugin_lto();
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// The default library location, we need this to find the runtime.
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// The location of crates will be determined as needed.
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@@ -1491,7 +1491,7 @@ fn are_upstream_rust_objects_already_included(sess: &Session) -> bool {
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Lto::Thin => {
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// If we defer LTO to the linker, we haven't run LTO ourselves, so
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// any upstream object files have not been copied yet.
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!sess.opts.debugging_opts.cross_lang_lto.enabled()
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!sess.opts.cg.linker_plugin_lto.enabled()
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}
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Lto::No |
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Lto::ThinLocal => false,
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@@ -159,7 +159,7 @@ pub(crate) fn run_thin(cgcx: &CodegenContext<LlvmCodegenBackend>,
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let symbol_white_list = symbol_white_list.iter()
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.map(|c| c.as_ptr())
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.collect::<Vec<_>>();
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if cgcx.opts.debugging_opts.cross_lang_lto.enabled() {
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if cgcx.opts.cg.linker_plugin_lto.enabled() {
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unreachable!("We should never reach this case if the LTO step \
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is deferred to the linker");
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}
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@@ -366,7 +366,7 @@ pub(crate) unsafe fn optimize(cgcx: &CodegenContext<LlvmCodegenBackend>,
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let opt_level = config.opt_level.map(|x| to_llvm_opt_settings(x).0)
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.unwrap_or(llvm::CodeGenOptLevel::None);
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let prepare_for_thin_lto = cgcx.lto == Lto::Thin || cgcx.lto == Lto::ThinLocal ||
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(cgcx.lto != Lto::Fat && cgcx.opts.debugging_opts.cross_lang_lto.enabled());
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(cgcx.lto != Lto::Fat && cgcx.opts.cg.linker_plugin_lto.enabled());
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with_llvm_pmb(llmod, &config, opt_level, prepare_for_thin_lto, &mut |b| {
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llvm::LLVMPassManagerBuilderPopulateFunctionPassManager(b, fpm);
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llvm::LLVMPassManagerBuilderPopulateModulePassManager(b, mpm);
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@@ -275,12 +275,12 @@ impl CodegenCx<'ll, 'tcx> {
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self.use_dll_storage_attrs && !self.tcx.is_foreign_item(def_id) &&
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// ThinLTO can't handle this workaround in all cases, so we don't
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// emit the attrs. Instead we make them unnecessary by disallowing
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// dynamic linking when cross-language LTO is enabled.
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!self.tcx.sess.opts.debugging_opts.cross_lang_lto.enabled();
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// dynamic linking when linker plugin based LTO is enabled.
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!self.tcx.sess.opts.cg.linker_plugin_lto.enabled();
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// If this assertion triggers, there's something wrong with commandline
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// argument validation.
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debug_assert!(!(self.tcx.sess.opts.debugging_opts.cross_lang_lto.enabled() &&
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debug_assert!(!(self.tcx.sess.opts.cg.linker_plugin_lto.enabled() &&
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self.tcx.sess.target.target.options.is_like_msvc &&
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self.tcx.sess.opts.cg.prefer_dynamic));
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@@ -13,7 +13,7 @@ use rustc::hir::def_id::{LOCAL_CRATE, CrateNum};
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use rustc::middle::dependency_format::Linkage;
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use rustc::session::Session;
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use rustc::session::config::{self, CrateType, OptLevel, DebugInfo,
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CrossLangLto, Lto};
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LinkerPluginLto, Lto};
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use rustc::ty::TyCtxt;
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use rustc_target::spec::{LinkerFlavor, LldFlavor};
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use serialize::{json, Encoder};
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@@ -127,7 +127,7 @@ pub trait Linker {
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fn subsystem(&mut self, subsystem: &str);
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fn group_start(&mut self);
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fn group_end(&mut self);
|
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fn cross_lang_lto(&mut self);
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fn linker_plugin_lto(&mut self);
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// Should have been finalize(self), but we don't support self-by-value on trait objects (yet?).
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fn finalize(&mut self) -> Command;
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}
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@@ -183,7 +183,7 @@ impl<'a> GccLinker<'a> {
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}
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}
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fn push_cross_lang_lto_args(&mut self, plugin_path: Option<&OsStr>) {
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fn push_linker_plugin_lto_args(&mut self, plugin_path: Option<&OsStr>) {
|
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if let Some(plugin_path) = plugin_path {
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let mut arg = OsString::from("-plugin=");
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arg.push(plugin_path);
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@@ -454,16 +454,16 @@ impl<'a> Linker for GccLinker<'a> {
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||||
}
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||||
}
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fn cross_lang_lto(&mut self) {
|
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match self.sess.opts.debugging_opts.cross_lang_lto {
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||||
CrossLangLto::Disabled => {
|
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fn linker_plugin_lto(&mut self) {
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match self.sess.opts.cg.linker_plugin_lto {
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LinkerPluginLto::Disabled => {
|
||||
// Nothing to do
|
||||
}
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||||
CrossLangLto::LinkerPluginAuto => {
|
||||
self.push_cross_lang_lto_args(None);
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||||
LinkerPluginLto::LinkerPluginAuto => {
|
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self.push_linker_plugin_lto_args(None);
|
||||
}
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||||
CrossLangLto::LinkerPlugin(ref path) => {
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self.push_cross_lang_lto_args(Some(path.as_os_str()));
|
||||
LinkerPluginLto::LinkerPlugin(ref path) => {
|
||||
self.push_linker_plugin_lto_args(Some(path.as_os_str()));
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -697,7 +697,7 @@ impl<'a> Linker for MsvcLinker<'a> {
|
||||
fn group_start(&mut self) {}
|
||||
fn group_end(&mut self) {}
|
||||
|
||||
fn cross_lang_lto(&mut self) {
|
||||
fn linker_plugin_lto(&mut self) {
|
||||
// Do nothing
|
||||
}
|
||||
}
|
||||
@@ -865,7 +865,7 @@ impl<'a> Linker for EmLinker<'a> {
|
||||
fn group_start(&mut self) {}
|
||||
fn group_end(&mut self) {}
|
||||
|
||||
fn cross_lang_lto(&mut self) {
|
||||
fn linker_plugin_lto(&mut self) {
|
||||
// Do nothing
|
||||
}
|
||||
}
|
||||
@@ -1047,7 +1047,7 @@ impl<'a> Linker for WasmLd<'a> {
|
||||
fn group_start(&mut self) {}
|
||||
fn group_end(&mut self) {}
|
||||
|
||||
fn cross_lang_lto(&mut self) {
|
||||
fn linker_plugin_lto(&mut self) {
|
||||
// Do nothing for now
|
||||
}
|
||||
}
|
||||
@@ -1207,6 +1207,6 @@ impl<'a> Linker for PtxLinker<'a> {
|
||||
fn group_end(&mut self) {
|
||||
}
|
||||
|
||||
fn cross_lang_lto(&mut self) {
|
||||
fn linker_plugin_lto(&mut self) {
|
||||
}
|
||||
}
|
||||
|
||||
@@ -126,7 +126,7 @@ impl ModuleConfig {
|
||||
self.time_passes = sess.time_passes();
|
||||
self.inline_threshold = sess.opts.cg.inline_threshold;
|
||||
self.obj_is_bitcode = sess.target.target.options.obj_is_bitcode ||
|
||||
sess.opts.debugging_opts.cross_lang_lto.enabled();
|
||||
sess.opts.cg.linker_plugin_lto.enabled();
|
||||
let embed_bitcode = sess.target.target.options.embed_bitcode ||
|
||||
sess.opts.debugging_opts.embed_bitcode;
|
||||
if embed_bitcode {
|
||||
@@ -737,7 +737,7 @@ fn execute_optimize_work_item<B: ExtraBackendMethods>(
|
||||
// If the linker does LTO, we don't have to do it. Note that we
|
||||
// keep doing full LTO, if it is requested, as not to break the
|
||||
// assumption that the output will be a single module.
|
||||
let linker_does_lto = cgcx.opts.debugging_opts.cross_lang_lto.enabled();
|
||||
let linker_does_lto = cgcx.opts.cg.linker_plugin_lto.enabled();
|
||||
|
||||
// When we're automatically doing ThinLTO for multi-codegen-unit
|
||||
// builds we don't actually want to LTO the allocator modules if
|
||||
@@ -1883,7 +1883,7 @@ pub fn pre_lto_bitcode_filename(module_name: &str) -> String {
|
||||
fn msvc_imps_needed(tcx: TyCtxt) -> bool {
|
||||
// This should never be true (because it's not supported). If it is true,
|
||||
// something is wrong with commandline arg validation.
|
||||
assert!(!(tcx.sess.opts.debugging_opts.cross_lang_lto.enabled() &&
|
||||
assert!(!(tcx.sess.opts.cg.linker_plugin_lto.enabled() &&
|
||||
tcx.sess.target.target.options.is_like_msvc &&
|
||||
tcx.sess.opts.cg.prefer_dynamic));
|
||||
|
||||
@@ -1891,6 +1891,6 @@ fn msvc_imps_needed(tcx: TyCtxt) -> bool {
|
||||
tcx.sess.crate_types.borrow().iter().any(|ct| *ct == config::CrateType::Rlib) &&
|
||||
// ThinLTO can't handle this workaround in all cases, so we don't
|
||||
// emit the `__imp_` symbols. Instead we make them unnecessary by disallowing
|
||||
// dynamic linking when cross-language LTO is enabled.
|
||||
!tcx.sess.opts.debugging_opts.cross_lang_lto.enabled()
|
||||
// dynamic linking when linker plugin LTO is enabled.
|
||||
!tcx.sess.opts.cg.linker_plugin_lto.enabled()
|
||||
}
|
||||
|
||||
@@ -3,7 +3,7 @@
|
||||
|
||||
// no-prefer-dynamic
|
||||
// only-msvc
|
||||
// compile-flags: -Z cross-lang-lto
|
||||
// compile-flags: -C linker-plugin-lto
|
||||
|
||||
#![crate_type = "rlib"]
|
||||
|
||||
|
||||
@@ -3,7 +3,7 @@
|
||||
|
||||
// no-prefer-dynamic
|
||||
// ignore-tidy-linelength
|
||||
// compile-flags: -C no-prepopulate-passes -C panic=abort -Z cross-lang-lto -Cpasses=name-anon-globals
|
||||
// compile-flags: -C no-prepopulate-passes -C panic=abort -C linker-plugin-lto -Cpasses=name-anon-globals
|
||||
|
||||
#![crate_type = "staticlib"]
|
||||
|
||||
|
||||
@@ -8,7 +8,7 @@
|
||||
all: cpp-executable rust-executable
|
||||
|
||||
cpp-executable:
|
||||
$(RUSTC) -Zcross-lang-lto=on -o $(TMPDIR)/librustlib-xlto.a -Copt-level=2 -Ccodegen-units=1 ./rustlib.rs
|
||||
$(RUSTC) -Clinker-plugin-lto=on -o $(TMPDIR)/librustlib-xlto.a -Copt-level=2 -Ccodegen-units=1 ./rustlib.rs
|
||||
$(CLANG) -flto=thin -fuse-ld=lld -L $(TMPDIR) -lrustlib-xlto -o $(TMPDIR)/cmain ./cmain.c -O3
|
||||
# Make sure we don't find a call instruction to the function we expect to
|
||||
# always be inlined.
|
||||
@@ -20,6 +20,6 @@ cpp-executable:
|
||||
rust-executable:
|
||||
$(CLANG) ./clib.c -flto=thin -c -o $(TMPDIR)/clib.o -O2
|
||||
(cd $(TMPDIR); $(AR) crus ./libxyz.a ./clib.o)
|
||||
$(RUSTC) -Zcross-lang-lto=on -L$(TMPDIR) -Copt-level=2 -Clinker=$(CLANG) -Clink-arg=-fuse-ld=lld ./main.rs -o $(TMPDIR)/rsmain
|
||||
$(RUSTC) -Clinker-plugin-lto=on -L$(TMPDIR) -Copt-level=2 -Clinker=$(CLANG) -Clink-arg=-fuse-ld=lld ./main.rs -o $(TMPDIR)/rsmain
|
||||
llvm-objdump -d $(TMPDIR)/rsmain | $(CGREP) -e "call.*c_never_inlined"
|
||||
llvm-objdump -d $(TMPDIR)/rsmain | $(CGREP) -v -e "call.*c_always_inlined"
|
||||
|
||||
@@ -5,13 +5,13 @@
|
||||
ifndef IS_WINDOWS
|
||||
|
||||
# This test makes sure that we don't loose upstream object files when compiling
|
||||
# staticlibs with -Zcross-lang-lto
|
||||
# staticlibs with -C linker-plugin-lto
|
||||
|
||||
all: staticlib.rs upstream.rs
|
||||
$(RUSTC) upstream.rs -Z cross-lang-lto -Ccodegen-units=1
|
||||
$(RUSTC) upstream.rs -C linker-plugin-lto -Ccodegen-units=1
|
||||
|
||||
# Check No LTO
|
||||
$(RUSTC) staticlib.rs -Z cross-lang-lto -Ccodegen-units=1 -L. -o $(TMPDIR)/staticlib.a
|
||||
$(RUSTC) staticlib.rs -C linker-plugin-lto -Ccodegen-units=1 -L. -o $(TMPDIR)/staticlib.a
|
||||
(cd $(TMPDIR); $(LD_LIB_PATH_ENVVAR)=$(REAL_LD_LIBRARY_PATH) llvm-ar x ./staticlib.a)
|
||||
# Make sure the upstream object file was included
|
||||
ls $(TMPDIR)/upstream.*.rcgu.o
|
||||
@@ -20,8 +20,8 @@ all: staticlib.rs upstream.rs
|
||||
rm $(TMPDIR)/*
|
||||
|
||||
# Check ThinLTO
|
||||
$(RUSTC) upstream.rs -Z cross-lang-lto -Ccodegen-units=1 -Clto=thin
|
||||
$(RUSTC) staticlib.rs -Z cross-lang-lto -Ccodegen-units=1 -Clto=thin -L. -o $(TMPDIR)/staticlib.a
|
||||
$(RUSTC) upstream.rs -C linker-plugin-lto -Ccodegen-units=1 -Clto=thin
|
||||
$(RUSTC) staticlib.rs -C linker-plugin-lto -Ccodegen-units=1 -Clto=thin -L. -o $(TMPDIR)/staticlib.a
|
||||
(cd $(TMPDIR); $(LD_LIB_PATH_ENVVAR)=$(REAL_LD_LIBRARY_PATH) llvm-ar x ./staticlib.a)
|
||||
ls $(TMPDIR)/upstream.*.rcgu.o
|
||||
|
||||
|
||||
@@ -7,14 +7,14 @@ ifndef IS_WINDOWS
|
||||
|
||||
# This test makes sure that the object files we generate are actually
|
||||
# LLVM bitcode files (as used by linker LTO plugins) when compiling with
|
||||
# -Z cross-lang-lto.
|
||||
# -Clinker-plugin-lto.
|
||||
|
||||
# this only succeeds for bitcode files
|
||||
ASSERT_IS_BITCODE_OBJ=($(LD_LIB_PATH_ENVVAR)=$(REAL_LD_LIBRARY_PATH) llvm-bcanalyzer $(1))
|
||||
EXTRACT_OBJS=(cd $(TMPDIR); rm -f ./*.o; $(LD_LIB_PATH_ENVVAR)=$(REAL_LD_LIBRARY_PATH) llvm-ar x $(1))
|
||||
|
||||
BUILD_LIB=$(RUSTC) lib.rs -Copt-level=2 -Z cross-lang-lto=on -Ccodegen-units=1
|
||||
BUILD_EXE=$(RUSTC) main.rs -Copt-level=2 -Z cross-lang-lto=on -Ccodegen-units=1 --emit=obj
|
||||
BUILD_LIB=$(RUSTC) lib.rs -Copt-level=2 -Clinker-plugin-lto -Ccodegen-units=1
|
||||
BUILD_EXE=$(RUSTC) main.rs -Copt-level=2 -Clinker-plugin-lto -Ccodegen-units=1 --emit=obj
|
||||
|
||||
all: staticlib staticlib-fat-lto staticlib-thin-lto rlib exe cdylib rdylib
|
||||
|
||||
|
||||
Reference in New Issue
Block a user