Rollup merge of #92435 - bjorn3:sync_cg_clif-2021-12-30, r=bjorn3

Sync rustc_codegen_cranelift

The main highlight this sync is enforcing rustfmt and lack of warnings on cg_clif's CI. I will open a separate PR to remove the cg_clif exceptions for them from this repo.

r? `@ghost`

`@rustbot` label +A-codegen +A-cranelift +T-compiler

Author: matthiaskrgr

compiler/rustc_codegen_cranelift/.github/workflows/main.yml

@@ -5,6 +5,21 @@ on:
   - pull_request
 
 jobs:
+  rustfmt:
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Install rustfmt
+      run: |
+        rustup component add rustfmt
+
+    - name: Rustfmt
+      run: |
+        cargo fmt --check
+
   build:
     runs-on: ${{ matrix.os }}
     timeout-minutes: 60

compiler/rustc_codegen_cranelift/.github/workflows/nightly-cranelift.yml

@@ -3,7 +3,7 @@ name: Test nightly Cranelift
 on:
   push:
   schedule:
-    - cron: '1 17 * * *' # At 01:17 UTC every day.
+    - cron: '17 1 * * *' # At 01:17 UTC every day.
 
 jobs:
   build:

compiler/rustc_codegen_cranelift/.gitignore

@@ -7,6 +7,7 @@ perf.data.old
 *.events
 *.string*
 /y.bin
+/y.bin.dSYM
 /build
 /build_sysroot/sysroot_src
 /build_sysroot/compiler-builtins

compiler/rustc_codegen_cranelift/Cargo.toml

@@ -40,31 +40,12 @@ unstable-features = ["jit", "inline_asm"]
 jit = ["cranelift-jit", "libloading"]
 inline_asm = []
 
-[profile.dev]
-# By compiling dependencies with optimizations, performing tests gets much faster.
-opt-level = 3
-
-[profile.dev.package.rustc_codegen_cranelift]
-# Disabling optimizations for cg_clif itself makes compilation after a change faster.
-opt-level = 0
-
-[profile.release.package.rustc_codegen_cranelift]
-incremental = true
-
 # Disable optimizations and debuginfo of build scripts and some of the heavy build deps, as the
 # execution time of build scripts is so fast that optimizing them slows down the total build time.
-[profile.dev.build-override]
-opt-level = 0
-debug = false
-
 [profile.release.build-override]
 opt-level = 0
 debug = false
 
-[profile.dev.package.cranelift-codegen-meta]
-opt-level = 0
-debug = false
-
 [profile.release.package.cranelift-codegen-meta]
 opt-level = 0
 debug = false

compiler/rustc_codegen_cranelift/Readme.md

@@ -37,7 +37,7 @@ Assuming `$cg_clif_dir` is the directory you cloned this repo into and you follo
 In the directory with your project (where you can do the usual `cargo build`), run:
 
 ```bash
-$ $cg_clif_dir/build/cargo build
+$ $cg_clif_dir/build/cargo-clif build
 ```
 
 This will build your project with rustc_codegen_cranelift instead of the usual LLVM backend.

compiler/rustc_codegen_cranelift/build_system/build_backend.rs

@@ -10,6 +10,18 @@ pub(crate) fn build_backend(
     let mut cmd = Command::new("cargo");
     cmd.arg("build").arg("--target").arg(host_triple);
 
+    cmd.env("CARGO_BUILD_INCREMENTAL", "true"); // Force incr comp even in release mode
+
+    let mut rustflags = env::var("RUSTFLAGS").unwrap_or_default();
+
+    if env::var("CI").as_ref().map(|val| &**val) == Ok("true") {
+        // Deny warnings on CI
+        rustflags += " -Dwarnings";
+
+        // Disabling incr comp reduces cache size and incr comp doesn't save as much on CI anyway
+        cmd.env("CARGO_BUILD_INCREMENTAL", "false");
+    }
+
     if use_unstable_features {
         cmd.arg("--features").arg("unstable-features");
     }
@@ -22,25 +34,20 @@ pub(crate) fn build_backend(
         _ => unreachable!(),
     }
 
+    // Set the rpath to make the cg_clif executable find librustc_codegen_cranelift without changing
+    // LD_LIBRARY_PATH
     if cfg!(unix) {
         if cfg!(target_os = "macos") {
-            cmd.env(
-                "RUSTFLAGS",
-                "-Csplit-debuginfo=unpacked \
+            rustflags += " -Csplit-debuginfo=unpacked \
                 -Clink-arg=-Wl,-rpath,@loader_path/../lib \
-                -Zosx-rpath-install-name"
-                    .to_string()
-                    + env::var("RUSTFLAGS").as_deref().unwrap_or(""),
-            );
+                -Zosx-rpath-install-name";
         } else {
-            cmd.env(
-                "RUSTFLAGS",
-                "-Clink-arg=-Wl,-rpath=$ORIGIN/../lib ".to_string()
-                    + env::var("RUSTFLAGS").as_deref().unwrap_or(""),
-            );
+            rustflags += " -Clink-arg=-Wl,-rpath=$ORIGIN/../lib ";
         }
     }
 
+    cmd.env("RUSTFLAGS", rustflags);
+
     eprintln!("[BUILD] rustc_codegen_cranelift");
     crate::utils::spawn_and_wait(cmd);
 

compiler/rustc_codegen_cranelift/build_system/build_sysroot.rs

@@ -46,9 +46,9 @@ pub(crate) fn build_sysroot(
     // Build and copy cargo wrapper
     let mut build_cargo_wrapper_cmd = Command::new("rustc");
     build_cargo_wrapper_cmd
-        .arg("scripts/cargo.rs")
+        .arg("scripts/cargo-clif.rs")
         .arg("-o")
-        .arg(target_dir.join("cargo"))
+        .arg(target_dir.join("cargo-clif"))
         .arg("-g");
     spawn_and_wait(build_cargo_wrapper_cmd);
 

compiler/rustc_codegen_cranelift/docs/usage.md

@@ -9,7 +9,7 @@ Assuming `$cg_clif_dir` is the directory you cloned this repo into and you follo
 In the directory with your project (where you can do the usual `cargo build`), run:
 
 ```bash
-$ $cg_clif_dir/build/cargo build
+$ $cg_clif_dir/build/cargo-clif build
 ```
 
 This will build your project with rustc_codegen_cranelift instead of the usual LLVM backend.
@@ -32,7 +32,7 @@ In jit mode cg_clif will immediately execute your code without creating an execu
 > The jit mode will probably need cargo integration to make this possible.
 
 ```bash
-$ $cg_clif_dir/build/cargo jit
+$ $cg_clif_dir/build/cargo-clif jit
 ```
 
 or
@@ -45,7 +45,7 @@ There is also an experimental lazy jit mode. In this mode functions are only com
 first called.
 
 ```bash
-$ $cg_clif_dir/build/cargo lazy-jit
+$ $cg_clif_dir/build/cargo-clif lazy-jit
 ```
 
 ## Shell

compiler/rustc_codegen_cranelift/example/mini_core_hello_world.rs

@@ -129,6 +129,7 @@ fn call_return_u128_pair() {
     return_u128_pair();
 }
 
+#[allow(unreachable_code)] // FIXME false positive
 fn main() {
     take_unique(Unique {
         pointer: 0 as *const (),

compiler/rustc_codegen_cranelift/rust-toolchain

@@ -1,3 +1,3 @@
 [toolchain]
-channel = "nightly-2021-12-20"
+channel = "nightly-2021-12-30"
 components = ["rust-src", "rustc-dev", "llvm-tools-preview"]