Assembly tests

.github/workflows/ci.yml

@@ -60,7 +60,7 @@ jobs:
             rust:
               toolchain: nightly
             # Run on nightly to help find regressions
-            args: --features tests/ui
+            test-args: --features tests/ui
           - name: Build macOS 32bit
             os: macos-10.15
             target: i686-apple-darwin
@@ -77,14 +77,15 @@ jobs:
           - name: Test GNUStep
             os: ubuntu-latest
             target: x86_64-unknown-linux-gnu
-            features: gnustep-1-9
-            args: --features gnustep-1-9
+            host-args: --features block-sys/gnustep-1-9,objc-sys/gnustep-1-9
+            args: --features block-sys/gnustep-1-9,objc-sys/gnustep-1-9
           - name: Test GNUStep 32bit
             os: ubuntu-latest
             target: i686-unknown-linux-gnu
             cflags: -m32
             configureflags: --target=x86-pc-linux-gnu
-            args: --features gnustep-1-9
+            host-args: --features block-sys/gnustep-1-9,objc-sys/gnustep-1-9
+            args: --features block-sys/gnustep-1-9,objc-sys/gnustep-1-9
           - name: Test iOS simulator x86 64bit
             os: macos-11
             target: x86_64-apple-ios
@@ -270,28 +271,6 @@ jobs:
       if: matrix.dinghy && steps.extern-cache.outputs.cache-hit != 'true'
       run: cargo install cargo-dinghy --version=^0.4 --root=$HOME/extern --target=x86_64-apple-darwin
 
-    - name: Run Cargo Dinghy
-      if: matrix.dinghy
-      run: |
-        # Launch the simulator
-        xcrun simctl list runtimes
-        RUNTIME_ID=$(xcrun simctl list runtimes | grep iOS | cut -d ' ' -f 7 | tail -1)
-        export SIM_ID=$(xcrun simctl create My-iphone7 com.apple.CoreSimulator.SimDeviceType.iPhone-7 $RUNTIME_ID)
-        xcrun simctl boot $SIM_ID
-
-        # Build
-        cargo dinghy build
-
-        # Run tests
-        cargo dinghy --device=$SIM_ID test --no-default-features
-        # Enable a few features. We're doing it this way because cargo dingy
-        # doesn't support specifying features from a workspace.
-        sed -i -e '/\[features\]/a\
-        default = ["exception", "verify_message", "catch_all"]
-        ' objc2/Cargo.toml
-        cargo dinghy --device=$SIM_ID test
-        cargo dinghy --device=$SIM_ID test --release
-
     - name: Build
       if: ${{ !matrix.dinghy }}
       uses: actions-rs/cargo@v1
@@ -343,3 +322,36 @@ jobs:
         command: test
         # Not using --all-features because that would enable e.g. gnustep
         args: --features ${{ env.FEATURES }},${{ env.UNSTABLE_FEATURES }} ${{ env.TESTARGS }}
+
+    - name: Run assembly tests
+      # Not run on GNUStep yet since a lot of function labels are mangled and
+      # not inlined (and hence quite hard to match on, at some point we'll
+      # need to find a solution to that).
+      if: ${{ !contains(matrix.os, 'ubuntu') }}
+      shell: bash
+      run:
+        export HOST_TARGET=$(rustc -vV | grep host | cut -f2 -d' ')
+
+        cargo run ${{ matrix.host-args }} --features assembly --target=$HOST_TARGET test_assembly ${{ matrix.args }}
+
+    - name: Run Cargo Dinghy
+      if: matrix.dinghy
+      run: |
+        # Launch the simulator
+        xcrun simctl list runtimes
+        RUNTIME_ID=$(xcrun simctl list runtimes | grep iOS | cut -d ' ' -f 7 | tail -1)
+        export SIM_ID=$(xcrun simctl create My-iphone7 com.apple.CoreSimulator.SimDeviceType.iPhone-7 $RUNTIME_ID)
+        xcrun simctl boot $SIM_ID
+
+        # Build
+        cargo dinghy build
+
+        # Run tests
+        cargo dinghy --device=$SIM_ID test --no-default-features
+        # Enable a few features. We're doing it this way because cargo dingy
+        # doesn't support specifying features from a workspace.
+        sed -i -e '/\[features\]/a\
+        default = ["exception", "verify_message", "catch_all"]
+        ' objc2/Cargo.toml
+        cargo dinghy --device=$SIM_ID test
+        cargo dinghy --device=$SIM_ID test --release

Cargo.toml

@@ -7,4 +7,5 @@ members = [
     "block2",
     "block-sys",
     "tests",
+    "tests/assembly/*",
 ]

tests/Cargo.toml

@@ -18,6 +18,7 @@ build = "build.rs"
 #
 # Also, they're slower than most tests.
 ui = ["trybuild"]
+assembly = ["cargo_metadata"]
 
 [dependencies]
 block2 = { path = "../block2" }
@@ -29,9 +30,14 @@ objc2-foundation = { path = "../objc2-foundation" }
 
 # Put here instead of dev-dependencies because we want to make it optional
 trybuild = { version = "1.0", optional = true }
+cargo_metadata = { version = "0.14", optional = true }
 
 [build-dependencies]
 cc = "1.0"
 
 [dev-dependencies]
 paste = "1.0"
+
+[[bin]]
+name = "test_assembly"
+required-features = ["assembly"]

tests/assembly/test_msg_send_zero_cost/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "test_msg_send_zero_cost"
+version = "0.1.0"
+edition = "2018"
+publish = false
+
+[lib]
+path = "lib.rs"
+
+[dependencies]
+objc2 = { path = "../../../objc2" }
+objc-sys = { path = "../../../objc-sys" }
+block-sys = { path = "../../../block-sys" }

tests/assembly/test_msg_send_zero_cost/expected/aarch64-apple-darwin.s

@@ -0,0 +1,7 @@
+	.section	__TEXT,__text,regular,pure_instructions
+	.globl	_handle
+	.p2align	2
+_handle:
+	b	_objc_msgSend
+
+.subsections_via_symbols

tests/assembly/test_msg_send_zero_cost/expected/aarch64-apple-ios-sim.s

@@ -0,0 +1,11 @@
+	.section	__TEXT,__text,regular,pure_instructions
+	.globl	_handle
+	.p2align	2
+_handle:
+	b	_objc_msgSend
+
+; Stripped __LLVM section
+
+; Stripped __LLVM section
+
+.subsections_via_symbols

tests/assembly/test_msg_send_zero_cost/expected/aarch64-apple-ios.s

@@ -0,0 +1,11 @@
+	.section	__TEXT,__text,regular,pure_instructions
+	.globl	_handle
+	.p2align	2
+_handle:
+	b	_objc_msgSend
+
+; Stripped __LLVM section
+
+; Stripped __LLVM section
+
+.subsections_via_symbols

tests/assembly/test_msg_send_zero_cost/expected/armv7-apple-ios.s

@@ -0,0 +1,10 @@
+	.section	__TEXT,__text,regular,pure_instructions
+	.ios_version_min 7, 0
+	.syntax unified
+	.globl	_handle
+	.p2align	2
+	.code	32
+_handle:
+	b	_objc_msgSend
+
+.subsections_via_symbols

tests/assembly/test_msg_send_zero_cost/expected/armv7s-apple-ios.s

@@ -0,0 +1,12 @@
+	.section	__TEXT,__text,regular,pure_instructions
+	.syntax unified
+	.globl	_handle
+	.p2align	2
+	.code	32
+_handle:
+	push	{r7, lr}
+	mov	r7, sp
+	bl	_objc_msgSend
+	pop	{r7, pc}
+
+.subsections_via_symbols

tests/assembly/test_msg_send_zero_cost/expected/i386-apple-ios.s

@@ -0,0 +1,11 @@
+	.section	__TEXT,__text,regular,pure_instructions
+	.intel_syntax noprefix
+	.globl	_handle
+	.p2align	4, 0x90
+_handle:
+	push	ebp
+	mov	ebp, esp
+	pop	ebp
+	jmp	_objc_msgSend
+
+.subsections_via_symbols

tests/assembly/test_msg_send_zero_cost/expected/i686-apple-darwin.s

@@ -0,0 +1,11 @@
+	.section	__TEXT,__text,regular,pure_instructions
+	.intel_syntax noprefix
+	.globl	_handle
+	.p2align	4, 0x90
+_handle:
+	push	ebp
+	mov	ebp, esp
+	pop	ebp
+	jmp	_objc_msgSend
+
+.subsections_via_symbols

tests/assembly/test_msg_send_zero_cost/expected/x86_64-apple-darwin.s

@@ -0,0 +1,11 @@
+	.section	__TEXT,__text,regular,pure_instructions
+	.intel_syntax noprefix
+	.globl	_handle
+	.p2align	4, 0x90
+_handle:
+	push	rbp
+	mov	rbp, rsp
+	pop	rbp
+	jmp	_objc_msgSend
+
+.subsections_via_symbols

tests/assembly/test_msg_send_zero_cost/expected/x86_64-apple-ios.s

@@ -0,0 +1,11 @@
+	.section	__TEXT,__text,regular,pure_instructions
+	.intel_syntax noprefix
+	.globl	_handle
+	.p2align	4, 0x90
+_handle:
+	push	rbp
+	mov	rbp, rsp
+	pop	rbp
+	jmp	_objc_msgSend
+
+.subsections_via_symbols

tests/assembly/test_msg_send_zero_cost/lib.rs

@@ -0,0 +1,9 @@
+//! Test that the inner part of msg_send! is inlined into an objc_msgSend
+
+use objc2::runtime::{Object, Sel};
+use objc2::MessageReceiver;
+
+#[no_mangle]
+pub fn handle(obj: &Object, sel: Sel) -> *mut Object {
+    unsafe { MessageReceiver::send_message(&obj, sel, ()).unwrap() }
+}

tests/build.rs

@@ -22,5 +22,8 @@ fn main() {
         builder.flag(flag);
     }
 
+    // For assembly tests
+    println!("cargo:rustc-env=TARGET={}", env::var("TARGET").unwrap());
+
     builder.compile("libencode_utils.a");
 }

tests/src/bin/test_assembly.rs

@@ -0,0 +1,137 @@
+//! A helper script for testing the assembly output.
+//!
+//! Similar to `trybuild` and `compiletest`, except specialized to our setup!
+
+use cargo_metadata::Message;
+use std::env;
+use std::env::args;
+use std::fmt::Write;
+use std::fs;
+use std::io;
+use std::path::Path;
+use std::process::{Command, Stdio};
+
+fn strip_lines(data: &str, starts_with: &str) -> String {
+    data.lines()
+        .filter(|line| !line.trim_start().starts_with(starts_with))
+        .collect::<Vec<_>>()
+        .join("\n")
+}
+
+fn strip_section(data: &str, section: &str) -> String {
+    let mut res = String::with_capacity(data.len());
+    let mut in_removed_section = false;
+    for line in data.lines() {
+        // This only works for the __LLVM sections we're interested in
+        if line == "" {
+            in_removed_section = false;
+        }
+        if line.trim().starts_with(".section") {
+            if line.contains(section) {
+                in_removed_section = true;
+                write!(res, "; Stripped {section} section\n").unwrap();
+            } else {
+                in_removed_section = false;
+            }
+        }
+        if !in_removed_section {
+            res.push_str(line);
+            res.push('\n');
+        }
+    }
+    res
+}
+
+fn read_assembly<P: AsRef<Path>>(path: P) -> io::Result<String> {
+    let s = fs::read_to_string(path)?;
+    let workspace_dir = Path::new(env!("CARGO_MANIFEST_DIR"))
+        .parent()
+        .unwrap()
+        .as_os_str()
+        .to_str()
+        .unwrap();
+    let s = s.replace(workspace_dir, "$WORKSPACE");
+    let s = strip_lines(&s, ".cfi_");
+    let s = strip_lines(&s, ".macosx_version_");
+    let s = strip_lines(&s, ".ios_version_");
+    let s = strip_lines(&s, ".build_version");
+    // We remove the __LLVM,__bitcode and __LLVM,__cmdline sections because
+    // they're uninteresting for out use-case.
+    //
+    // See https://github.com/rust-lang/rust/blob/1.59.0/compiler/rustc_codegen_llvm/src/back/write.rs#L978-L1074
+    Ok(strip_section(&s, "__LLVM"))
+}
+
+fn main() {
+    let manifest_dir = Path::new(env!("CARGO_MANIFEST_DIR"));
+    let should_overwrite = option_env!("TEST_OVERWRITE").is_some();
+    let host = env!("TARGET");
+
+    for entry in manifest_dir.join("assembly").read_dir().unwrap() {
+        let package_path = entry.unwrap().path();
+        let package = package_path.file_name().unwrap().to_str().unwrap();
+
+        println!("Testing {package}.");
+
+        let result = Command::new(std::env::var("CARGO").unwrap_or("cargo".into()))
+            // .arg("+nightly")
+            // .arg("-Zbuild-std")
+            // .arg("-vv")
+            .arg("rustc")
+            .arg(format!("--package={package}"))
+            .args(args().skip(2))
+            .arg("--release")
+            .arg("--message-format=json-render-diagnostics")
+            .arg("--")
+            .arg("--emit=asm")
+            .arg("-Cllvm-args=--x86-asm-syntax=intel")
+            .stdout(Stdio::piped())
+            .stderr(Stdio::inherit())
+            .output()
+            .unwrap();
+
+        let artifact = Message::parse_stream(&*result.stdout)
+            .find_map(|message| {
+                if let Message::CompilerArtifact(artifact) = message.unwrap() {
+                    // Brittle!
+                    if artifact.target.name == package && artifact.filenames.len() == 2 {
+                        let path = artifact.filenames[1].clone();
+                        let stem = path.file_stem().unwrap().strip_prefix("lib").unwrap();
+                        return Some(path.with_file_name(format!("{stem}.s")));
+                    }
+                }
+                None
+            })
+            .unwrap_or_else(|| {
+                panic!(
+                    "Could not find package data:\n{}",
+                    String::from_utf8_lossy(&result.stdout)
+                )
+            });
+
+        // Very brittle!
+        let target = artifact
+            .components()
+            .map(|component| component.as_str())
+            .skip_while(|&component| component != "target")
+            .skip(1)
+            .next()
+            .unwrap_or(host);
+
+        println!("Target {target}.");
+
+        let expected_file = package_path.join("expected").join(format!("{target}.s"));
+
+        let actual = read_assembly(&artifact).unwrap();
+        if should_overwrite {
+            fs::write(expected_file, actual).unwrap();
+        } else if let Ok(expected) = read_assembly(expected_file) {
+            if expected != actual {
+                eprintln!("\n===Expected===\n{}\n===Actual===\n{}", expected, actual);
+                panic!("Expected and actual did not match.");
+            }
+        } else {
+            panic!("Missing assembly output for target {}:\n{}", target, actual);
+        }
+    }
+}