Add test run to cranelift-filetests to allow executing CLIF (#890)

* Add ability to run CLIF IR using `clif-util run [-v] {file}` and add `test run` to cranelift-filetests to allow executing CLIF

This re-factors the compile/execute parts to a FunctionRunner that is shared between cranelift-filetests and clif-util. CLIF can be now be run using `clif-util run` as well as during `clif-util test` for files with a `test run` header. As before, only functions suffixed with a `run` comment are executed. The `run: fn(...) == ...` expression syntax is left for a subsequent change.

cranelift/Cargo.toml

@@ -42,6 +42,7 @@ target-lexicon = "0.4.0"
 pretty_env_logger = "0.3.0"
 file-per-thread-logger = "0.1.2"
 indicatif = "0.11.0"
+walkdir = "2.2"
 
 [features]
 default = ["disas", "wasm", "cranelift-codegen/all-arch"]

cranelift/codegen/src/binemit/memorysink.rs

@@ -162,6 +162,16 @@ impl<'a> CodeSink for MemoryCodeSink<'a> {
     }
 }
 
+/// A `RelocSink` implementation that does nothing, which is convenient when
+/// compiling code that does not relocate anything.
+pub struct NullRelocSink {}
+
+impl RelocSink for NullRelocSink {
+    fn reloc_ebb(&mut self, _: u32, _: Reloc, _: u32) {}
+    fn reloc_external(&mut self, _: u32, _: Reloc, _: &ExternalName, _: i64) {}
+    fn reloc_jt(&mut self, _: u32, _: Reloc, _: JumpTable) {}
+}
+
 /// A `TrapSink` implementation that does nothing, which is convenient when
 /// compiling code that does not rely on trapping semantics.
 pub struct NullTrapSink {}

cranelift/codegen/src/binemit/mod.rs

@@ -9,7 +9,8 @@ mod shrink;
 mod stackmap;
 
 pub use self::memorysink::{
-    MemoryCodeSink, NullStackmapSink, NullTrapSink, RelocSink, StackmapSink, TrapSink,
+    MemoryCodeSink, NullRelocSink, NullStackmapSink, NullTrapSink, RelocSink, StackmapSink,
+    TrapSink,
 };
 pub use self::relaxation::relax_branches;
 pub use self::shrink::shrink_instructions;

cranelift/filetests/Cargo.toml

@@ -11,9 +11,12 @@ edition = "2018"
 
 [dependencies]
 cranelift-codegen = { path = "../cranelift-codegen", version = "0.40.0", features = ["testing_hooks"] }
+cranelift-native = { path = "../cranelift-native", version = "0.40.0" }
 cranelift-reader = { path = "../cranelift-reader", version = "0.40.0" }
 cranelift-preopt = { path = "../cranelift-preopt", version = "0.40.0" }
 file-per-thread-logger = "0.1.2"
 filecheck = "0.4.0"
-num_cpus = "1.8.0"
 log = "0.4.6"
+mmap = "0.1.1"
+num_cpus = "1.8.0"
+region = "2.1.2"

cranelift/filetests/filetests/isa/x86/run-const.clif

@@ -0,0 +1,11 @@
+test run
+
+function %test_compare_i32() -> b1 {
+ebb0:
+    v0 = iconst.i32 42
+    v1 = iconst.i32 42
+    v2 = icmp eq v0, v1
+    return v2
+}
+
+; run

cranelift/filetests/src/function_runner.rs

@@ -0,0 +1,118 @@
+use core::mem;
+use cranelift_codegen::binemit::{NullRelocSink, NullStackmapSink, NullTrapSink};
+use cranelift_codegen::ir::Function;
+use cranelift_codegen::isa::{CallConv, TargetIsa};
+use cranelift_codegen::{settings, Context};
+use cranelift_native::builder as host_isa_builder;
+use mmap::{MapOption, MemoryMap};
+use region;
+use region::Protection;
+
+/// Run a function on a host
+pub struct FunctionRunner {
+    function: Function,
+    isa: Box<dyn TargetIsa>,
+}
+
+impl FunctionRunner {
+    /// Build a function runner from a function and the ISA to run on (must be the host machine's ISA)
+    pub fn new(function: Function, isa: Box<dyn TargetIsa>) -> Self {
+        FunctionRunner { function, isa }
+    }
+
+    /// Build a function runner using the host machine's ISA and the passed flags
+    pub fn with_host_isa(function: Function, flags: settings::Flags) -> Self {
+        let builder = host_isa_builder().expect("Unable to build a TargetIsa for the current host");
+        let isa = builder.finish(flags);
+        FunctionRunner::new(function, isa)
+    }
+
+    /// Build a function runner using the host machine's ISA and the default flags for this ISA
+    pub fn with_default_host_isa(function: Function) -> Self {
+        let flags = settings::Flags::new(settings::builder());
+        FunctionRunner::with_host_isa(function, flags)
+    }
+
+    /// Compile and execute a single function, expecting a boolean to be returned; a 'true' value is
+    /// interpreted as a successful test execution and mapped to Ok whereas a 'false' value is
+    /// interpreted as a failed test and mapped to Err.
+    pub fn run(&self) -> Result<(), String> {
+        let func = self.function.clone();
+        if !(func.signature.params.is_empty()
+            && func.signature.returns.len() == 1
+            && func.signature.returns.first().unwrap().value_type.is_bool())
+        {
+            return Err(String::from(
+                "Functions must have a signature like: () -> boolean",
+            ));
+        }
+
+        if func.signature.call_conv != self.isa.default_call_conv()
+            && func.signature.call_conv != CallConv::Fast
+        {
+            // ideally we wouldn't have to also check for Fast here but currently there is no way to inform the filetest parser that we would like to use a default other than Fast
+            return Err(String::from(
+                "Functions only run on the host's default calling convention; remove the specified calling convention in the function signature to use the host's default.",
+            ));
+        }
+
+        // set up the context
+        let mut context = Context::new();
+        context.func = func;
+
+        // compile and encode the result to machine code
+        let relocs = &mut NullRelocSink {};
+        let traps = &mut NullTrapSink {};
+        let stackmaps = &mut NullStackmapSink {};
+        let code_info = context
+            .compile(self.isa.as_ref())
+            .map_err(|e| e.to_string())?;
+        let code_page = MemoryMap::new(code_info.total_size as usize, &[MapOption::MapWritable])
+            .map_err(|e| e.to_string())?;
+        let callable_fn: fn() -> bool = unsafe {
+            context.emit_to_memory(
+                self.isa.as_ref(),
+                code_page.data(),
+                relocs,
+                traps,
+                stackmaps,
+            );
+            region::protect(code_page.data(), code_page.len(), Protection::ReadExecute)
+                .map_err(|e| e.to_string())?;
+            mem::transmute(code_page.data())
+        };
+
+        // execute
+        match callable_fn() {
+            true => Ok(()),
+            false => Err(format!("Failed: {}", context.func.name.to_string())),
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use cranelift_reader::parse_test;
+
+    #[test]
+    fn nop() {
+        let code = String::from(
+            "function %test() -> b8 system_v {
+            ebb0:
+                nop
+                v1 = bconst.b8 true
+                return v1
+            }",
+        );
+
+        // extract function
+        let test_file = parse_test(code.as_str(), None, None).unwrap();
+        assert_eq!(1, test_file.functions.len());
+        let function = test_file.functions[0].0.clone();
+
+        // execute function
+        let runner = FunctionRunner::with_default_host_isa(function);
+        runner.run().unwrap() // will panic if execution fails
+    }
+}

cranelift/filetests/src/lib.rs

@@ -23,6 +23,7 @@
     )
 )]
 
+pub use crate::function_runner::FunctionRunner;
 use crate::runner::TestRunner;
 use cranelift_codegen::timing;
 use cranelift_reader::TestCommand;
@@ -30,6 +31,7 @@ use std::path::Path;
 use std::time;
 
 mod concurrent;
+mod function_runner;
 mod match_directive;
 mod runner;
 mod runone;
@@ -46,6 +48,7 @@ mod test_postopt;
 mod test_preopt;
 mod test_print_cfg;
 mod test_regalloc;
+mod test_run;
 mod test_safepoint;
 mod test_shrink;
 mod test_simple_gvn;
@@ -124,6 +127,7 @@ fn new_subtest(parsed: &TestCommand) -> subtest::SubtestResult<Box<dyn subtest::
         "simple_preopt" => test_simple_preopt::subtest(parsed),
         "print-cfg" => test_print_cfg::subtest(parsed),
         "regalloc" => test_regalloc::subtest(parsed),
+        "run" => test_run::subtest(parsed),
         "shrink" => test_shrink::subtest(parsed),
         "simple-gvn" => test_simple_gvn::subtest(parsed),
         "verifier" => test_verifier::subtest(parsed),

cranelift/filetests/src/test_run.rs

@@ -0,0 +1,46 @@
+//! Test command for running CLIF files and verifying their results
+//!
+//! The `run` test command compiles each function on the host machine and executes it
+
+use crate::function_runner::FunctionRunner;
+use crate::subtest::{Context, SubTest, SubtestResult};
+use cranelift_codegen;
+use cranelift_codegen::ir;
+use cranelift_reader::TestCommand;
+use std::borrow::Cow;
+
+struct TestRun;
+
+pub fn subtest(parsed: &TestCommand) -> SubtestResult<Box<dyn SubTest>> {
+    assert_eq!(parsed.command, "run");
+    if !parsed.options.is_empty() {
+        Err(format!("No options allowed on {}", parsed))
+    } else {
+        Ok(Box::new(TestRun))
+    }
+}
+
+impl SubTest for TestRun {
+    fn name(&self) -> &'static str {
+        "run"
+    }
+
+    fn is_mutating(&self) -> bool {
+        false
+    }
+
+    fn needs_isa(&self) -> bool {
+        false
+    }
+
+    fn run(&self, func: Cow<ir::Function>, context: &Context) -> SubtestResult<()> {
+        for comment in context.details.comments.iter() {
+            if comment.text.contains("run") {
+                let runner =
+                    FunctionRunner::with_host_isa(func.clone().into_owned(), context.flags.clone());
+                runner.run()?
+            }
+        }
+        Ok(())
+    }
+}

cranelift/src/clif-util.rs

@@ -33,6 +33,7 @@ mod cat;
 mod compile;
 mod disasm;
 mod print_cfg;
+mod run;
 mod utils;
 
 /// A command either succeeds or fails with an error message.
@@ -162,6 +163,13 @@ fn main() {
                 .arg(add_input_file_arg())
                 .arg(add_debug_flag()),
         )
+        .subcommand(
+            SubCommand::with_name("run")
+                .about("Execute CLIF code and verify with test expressions")
+                .arg(add_verbose_flag())
+                .arg(add_input_file_arg())
+                .arg(add_debug_flag()),
+        )
         .subcommand(
             SubCommand::with_name("cat")
                 .about("Outputs .clif file")
@@ -224,6 +232,14 @@ fn main() {
             )
             .map(|_time| ())
         }
+        ("run", Some(rest_cmd)) => {
+            handle_debug_flag(rest_cmd.is_present("debug"));
+            run::run(
+                get_vec(rest_cmd.values_of("file")),
+                rest_cmd.is_present("verbose"),
+            )
+            .map(|_time| ())
+        }
         ("pass", Some(rest_cmd)) => {
             handle_debug_flag(rest_cmd.is_present("debug"));
 

cranelift/src/run.rs

@@ -0,0 +1,118 @@
+//! CLI tool to compile Cranelift IR files to native code in memory and execute them.
+
+use crate::utils::read_to_string;
+use cranelift_codegen::isa::TargetIsa;
+use cranelift_filetests::FunctionRunner;
+use cranelift_native::builder as host_isa_builder;
+use cranelift_reader::{parse_test, Details, IsaSpec};
+use std::path::PathBuf;
+use walkdir::WalkDir;
+
+pub fn run(files: Vec<String>, flag_print: bool) -> Result<(), String> {
+    let mut total = 0;
+    let mut errors = 0;
+    for file in iterate_files(files) {
+        total += 1;
+        match run_single_file(&file) {
+            Ok(_) => {
+                if flag_print {
+                    println!("{}", file.to_string_lossy());
+                }
+            }
+            Err(e) => {
+                if flag_print {
+                    println!("{}: {}", file.to_string_lossy(), e);
+                }
+                errors += 1;
+            }
+        }
+    }
+
+    if flag_print {
+        match total {
+            0 => println!("0 files"),
+            1 => println!("1 file"),
+            n => println!("{} files", n),
+        }
+    }
+
+    match errors {
+        0 => Ok(()),
+        1 => Err(String::from("1 failure")),
+        n => Err(format!("{} failures", n)),
+    }
+}
+
+/// Iterate over all of the files passed as arguments, recursively iterating through directories
+fn iterate_files(files: Vec<String>) -> impl Iterator<Item = PathBuf> {
+    files
+        .into_iter()
+        .flat_map(WalkDir::new)
+        .filter(|f| match f {
+            Ok(d) => {
+                // filter out hidden files (starting with .)
+                !d.file_name().to_str().map_or(false, |s| s.starts_with("."))
+                    // filter out directories
+                    && !d.file_type().is_dir()
+            }
+            Err(e) => {
+                println!("Unable to read file: {}", e);
+                false
+            }
+        })
+        .map(|f| {
+            f.expect("This should not happen: we have already filtered out the errors")
+                .into_path()
+        })
+}
+
+/// Run all functions in a file that are succeeded by "run:" comments
+fn run_single_file(path: &PathBuf) -> Result<(), String> {
+    let file_contents = read_to_string(&path).map_err(|e| e.to_string())?;
+    run_file_contents(file_contents)
+}
+
+/// Main body of `run_single_file` separated for testing
+fn run_file_contents(file_contents: String) -> Result<(), String> {
+    let test_file = parse_test(&file_contents, None, None).map_err(|e| e.to_string())?;
+    for (func, Details { comments, .. }) in test_file.functions {
+        if comments.iter().any(|c| c.text.contains("run")) {
+            let isa = create_target_isa(&test_file.isa_spec)?;
+            FunctionRunner::new(func, isa).run()?
+        }
+    }
+    Ok(())
+}
+
+/// Build an ISA based on the current machine running this code (the host)
+fn create_target_isa(isa_spec: &IsaSpec) -> Result<Box<dyn TargetIsa>, String> {
+    if let IsaSpec::None(flags) = isa_spec {
+        // build an ISA for the current machine
+        let builder = host_isa_builder()?;
+        Ok(builder.finish(flags.clone()))
+    } else {
+        Err(String::from("A target ISA was specified in the file but should not have been--only the host ISA can be used for running CLIF files"))?
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn nop() {
+        let code = String::from(
+            "
+            function %test() -> b8 system_v {
+            ebb0:
+                nop
+                v1 = bconst.b8 true
+                return v1
+            }
+            
+            ; run
+            ",
+        );
+        run_file_contents(code).unwrap()
+    }
+}