Files
wasmtime/cranelift/filetests/src/function_runner.rs
Afonso Bordado 2beaf7352f cranelift: Test calling across different calling conventions (#4801)
* cranelift: Test calling across different calling conventions

* cranelift: Use `wasmtime_system_v` calling convention for cross cc tests
2022-08-31 15:16:41 -07:00

578 lines
22 KiB
Rust

//! Provides functionality for compiling and running CLIF IR for `run` tests.
use anyhow::{anyhow, Result};
use core::mem;
use cranelift_codegen::data_value::DataValue;
use cranelift_codegen::ir::{
condcodes::IntCC, ExternalName, Function, InstBuilder, Signature, UserExternalName,
UserFuncName,
};
use cranelift_codegen::isa::TargetIsa;
use cranelift_codegen::{ir, settings, CodegenError, Context};
use cranelift_frontend::{FunctionBuilder, FunctionBuilderContext};
use cranelift_jit::{JITBuilder, JITModule};
use cranelift_module::{FuncId, Linkage, Module, ModuleError};
use cranelift_native::builder_with_options;
use cranelift_reader::TestFile;
use std::cmp::max;
use std::collections::hash_map::Entry;
use std::collections::HashMap;
use thiserror::Error;
const TESTFILE_NAMESPACE: u32 = 0;
/// Holds information about a previously defined function.
#[derive(Debug)]
struct DefinedFunction {
/// This is the name that the function is internally known as.
///
/// The JIT module does not support linking / calling [TestcaseName]'s, so
/// we rename every function into a [UserExternalName].
///
/// By doing this we also have to rename functions that previously were using a
/// [UserFuncName], since they may now be in conflict after the renaming that
/// occurred.
new_name: UserExternalName,
/// The function signature
signature: ir::Signature,
/// JIT [FuncId]
func_id: FuncId,
}
/// Compile a test case.
///
/// Several Cranelift functions need the ability to run Cranelift IR (e.g. `test_run`); this
/// [TestFileCompiler] provides a way for compiling Cranelift [Function]s to
/// `CompiledFunction`s and subsequently calling them through the use of a `Trampoline`. As its
/// name indicates, this compiler is limited: any functionality that requires knowledge of things
/// outside the [Function] will likely not work (e.g. global values, calls). For an example of this
/// "outside-of-function" functionality, see `cranelift_jit::backend::JITBackend`.
///
/// ```
/// use cranelift_filetests::TestFileCompiler;
/// use cranelift_reader::parse_functions;
/// use cranelift_codegen::data_value::DataValue;
///
/// let code = "test run \n function %add(i32, i32) -> i32 { block0(v0:i32, v1:i32): v2 = iadd v0, v1 return v2 }".into();
/// let func = parse_functions(code).unwrap().into_iter().nth(0).unwrap();
/// let mut compiler = TestFileCompiler::with_default_host_isa().unwrap();
/// compiler.declare_function(&func).unwrap();
/// compiler.define_function(func.clone()).unwrap();
/// compiler.create_trampoline_for_function(&func).unwrap();
/// let compiled = compiler.compile().unwrap();
/// let trampoline = compiled.get_trampoline(&func).unwrap();
///
/// let returned = trampoline.call(&vec![DataValue::I32(2), DataValue::I32(40)]);
/// assert_eq!(vec![DataValue::I32(42)], returned);
/// ```
pub struct TestFileCompiler {
module: JITModule,
ctx: Context,
/// Holds info about the functions that have already been defined.
/// Use look them up by their original [UserFuncName] since that's how the caller
/// passes them to us.
defined_functions: HashMap<UserFuncName, DefinedFunction>,
/// We deduplicate trampolines by the signature of the function that they target.
/// This map holds as a key the [Signature] of the target function, and as a value
/// the [UserFuncName] of the trampoline for that [Signature].
///
/// The trampoline is defined in `defined_functions` as any other regular function.
trampolines: HashMap<Signature, UserFuncName>,
}
impl TestFileCompiler {
/// Build a [TestFileCompiler] from a [TargetIsa]. For functions to be runnable on the
/// host machine, this [TargetIsa] must match the host machine's ISA (see
/// [TestFileCompiler::with_host_isa]).
pub fn new(isa: Box<dyn TargetIsa>) -> Self {
let builder = JITBuilder::with_isa(isa, cranelift_module::default_libcall_names());
let module = JITModule::new(builder);
let ctx = module.make_context();
Self {
module,
ctx,
defined_functions: HashMap::new(),
trampolines: HashMap::new(),
}
}
/// Build a [TestFileCompiler] using the host machine's ISA and the passed flags.
pub fn with_host_isa(flags: settings::Flags) -> Result<Self> {
let builder =
builder_with_options(true).expect("Unable to build a TargetIsa for the current host");
let isa = builder.finish(flags)?;
Ok(Self::new(isa))
}
/// Build a [TestFileCompiler] using the host machine's ISA and the default flags for this
/// ISA.
pub fn with_default_host_isa() -> Result<Self> {
let flags = settings::Flags::new(settings::builder());
Self::with_host_isa(flags)
}
/// Registers all functions in a [TestFile]. Additionally creates a trampoline for each one
/// of them.
pub fn add_testfile(&mut self, testfile: &TestFile) -> Result<()> {
// Declare all functions in the file, so that they may refer to each other.
for (func, _) in &testfile.functions {
self.declare_function(func)?;
}
// Define all functions and trampolines
for (func, _) in &testfile.functions {
self.define_function(func.clone())?;
self.create_trampoline_for_function(func)?;
}
Ok(())
}
/// Declares a function an registers it as a linkable and callable target internally
pub fn declare_function(&mut self, func: &Function) -> Result<()> {
let next_id = self.defined_functions.len() as u32;
match self.defined_functions.entry(func.name.clone()) {
Entry::Occupied(_) => {
anyhow::bail!("Duplicate function with name {} found!", &func.name)
}
Entry::Vacant(v) => {
let name = func.name.to_string();
let func_id =
self.module
.declare_function(&name, Linkage::Local, &func.signature)?;
v.insert(DefinedFunction {
new_name: UserExternalName::new(TESTFILE_NAMESPACE, next_id),
signature: func.signature.clone(),
func_id,
});
}
};
Ok(())
}
/// Renames the function to its new [UserExternalName], as well as any other function that
/// it may reference.
///
/// We have to do this since the JIT cannot link Testcase functions.
fn apply_func_rename(
&self,
mut func: Function,
defined_func: &DefinedFunction,
) -> Result<Function> {
// First, rename the function
let func_original_name = func.name;
func.name = UserFuncName::User(defined_func.new_name.clone());
// Rename any functions that it references
// Do this in stages to appease the borrow checker
let mut redefines = Vec::with_capacity(func.dfg.ext_funcs.len());
for (ext_ref, ext_func) in &func.dfg.ext_funcs {
let old_name = match &ext_func.name {
ExternalName::TestCase(tc) => UserFuncName::Testcase(tc.clone()),
ExternalName::User(username) => {
UserFuncName::User(func.params.user_named_funcs()[*username].clone())
}
// The other cases don't need renaming, so lets just continue...
_ => continue,
};
let target_df = self.defined_functions.get(&old_name).ok_or(anyhow!(
"Undeclared function {} is referenced by {}!",
&old_name,
&func_original_name
))?;
redefines.push((ext_ref, target_df.new_name.clone()));
}
// Now register the redefines
for (ext_ref, new_name) in redefines.into_iter() {
// Register the new name in the func, so that we can get a reference to it.
let new_name_ref = func.params.ensure_user_func_name(new_name);
// Finally rename the ExtFunc
func.dfg.ext_funcs[ext_ref].name = ExternalName::User(new_name_ref);
}
Ok(func)
}
/// Defines the body of a function
pub fn define_function(&mut self, func: Function) -> Result<()> {
let defined_func = self
.defined_functions
.get(&func.name)
.ok_or(anyhow!("Undeclared function {} found!", &func.name))?;
self.ctx.func = self.apply_func_rename(func, defined_func)?;
self.module
.define_function(defined_func.func_id, &mut self.ctx)?;
self.module.clear_context(&mut self.ctx);
Ok(())
}
/// Creates and registers a trampoline for a function if none exists.
pub fn create_trampoline_for_function(&mut self, func: &Function) -> Result<()> {
if !self.defined_functions.contains_key(&func.name) {
anyhow::bail!("Undeclared function {} found!", &func.name);
}
// Check if a trampoline for this function signature already exists
if self.trampolines.contains_key(&func.signature) {
return Ok(());
}
// Create a trampoline and register it
let name = UserFuncName::user(TESTFILE_NAMESPACE, self.defined_functions.len() as u32);
let trampoline = make_trampoline(name.clone(), &func.signature, self.module.isa());
self.declare_function(&trampoline)?;
self.define_function(trampoline)?;
self.trampolines.insert(func.signature.clone(), name);
Ok(())
}
/// Finalize this TestFile and link all functions.
pub fn compile(mut self) -> Result<CompiledTestFile, CompilationError> {
// Finalize the functions which we just defined, which resolves any
// outstanding relocations (patching in addresses, now that they're
// available).
self.module.finalize_definitions();
Ok(CompiledTestFile {
module: Some(self.module),
defined_functions: self.defined_functions,
trampolines: self.trampolines,
})
}
}
/// A finalized Test File
pub struct CompiledTestFile {
/// We need to store [JITModule] since it contains the underlying memory for the functions.
/// Store it in an [Option] so that we can later drop it.
module: Option<JITModule>,
/// Holds info about the functions that have been registered in `module`.
/// See [TestFileCompiler] for more info.
defined_functions: HashMap<UserFuncName, DefinedFunction>,
/// Trampolines available in this [JITModule].
/// See [TestFileCompiler] for more info.
trampolines: HashMap<Signature, UserFuncName>,
}
impl CompiledTestFile {
/// Return a trampoline for calling.
///
/// Returns None if [TestFileCompiler::create_trampoline_for_function] wasn't called for this function.
pub fn get_trampoline(&self, func: &Function) -> Option<Trampoline> {
let defined_func = self.defined_functions.get(&func.name)?;
let trampoline_id = self
.trampolines
.get(&func.signature)
.and_then(|name| self.defined_functions.get(name))
.map(|df| df.func_id)?;
Some(Trampoline {
module: self.module.as_ref()?,
func_id: defined_func.func_id,
func_signature: &defined_func.signature,
trampoline_id,
})
}
}
impl Drop for CompiledTestFile {
fn drop(&mut self) {
// Freeing the module's memory erases the compiled functions.
// This should be safe since their pointers never leave this struct.
unsafe { self.module.take().unwrap().free_memory() }
}
}
/// A callable trampoline
pub struct Trampoline<'a> {
module: &'a JITModule,
func_id: FuncId,
func_signature: &'a Signature,
trampoline_id: FuncId,
}
impl<'a> Trampoline<'a> {
/// Call the target function of this trampoline, passing in [DataValue]s using a compiled trampoline.
pub fn call(&self, arguments: &[DataValue]) -> Vec<DataValue> {
let mut values = UnboxedValues::make_arguments(arguments, &self.func_signature);
let arguments_address = values.as_mut_ptr();
let function_ptr = self.module.get_finalized_function(self.func_id);
let trampoline_ptr = self.module.get_finalized_function(self.trampoline_id);
let callable_trampoline: fn(*const u8, *mut u128) -> () =
unsafe { mem::transmute(trampoline_ptr) };
callable_trampoline(function_ptr, arguments_address);
values.collect_returns(&self.func_signature)
}
}
/// Compilation Error when compiling a function.
#[derive(Error, Debug)]
pub enum CompilationError {
/// Cranelift codegen error.
#[error("Cranelift codegen error")]
CodegenError(#[from] CodegenError),
/// Module Error
#[error("Module error")]
ModuleError(#[from] ModuleError),
/// Memory mapping error.
#[error("Memory mapping error")]
IoError(#[from] std::io::Error),
}
/// A container for laying out the [ValueData]s in memory in a way that the [Trampoline] can
/// understand.
struct UnboxedValues(Vec<u128>);
impl UnboxedValues {
/// The size in bytes of each slot location in the allocated [DataValue]s. Though [DataValue]s
/// could be smaller than 16 bytes (e.g. `I16`), this simplifies the creation of the [DataValue]
/// array and could be used to align the slots to the largest used [DataValue] (i.e. 128-bit
/// vectors).
const SLOT_SIZE: usize = 16;
/// Build the arguments vector for passing the [DataValue]s into the [Trampoline]. The size of
/// `u128` used here must match [Trampoline::SLOT_SIZE].
pub fn make_arguments(arguments: &[DataValue], signature: &ir::Signature) -> Self {
assert_eq!(arguments.len(), signature.params.len());
let mut values_vec = vec![0; max(signature.params.len(), signature.returns.len())];
// Store the argument values into `values_vec`.
for ((arg, slot), param) in arguments.iter().zip(&mut values_vec).zip(&signature.params) {
assert!(
arg.ty() == param.value_type || arg.is_vector() || arg.is_bool(),
"argument type mismatch: {} != {}",
arg.ty(),
param.value_type
);
unsafe {
arg.write_value_to(slot);
}
}
Self(values_vec)
}
/// Return a pointer to the underlying memory for passing to the trampoline.
pub fn as_mut_ptr(&mut self) -> *mut u128 {
self.0.as_mut_ptr()
}
/// Collect the returned [DataValue]s into a [Vec]. The size of `u128` used here must match
/// [Trampoline::SLOT_SIZE].
pub fn collect_returns(&self, signature: &ir::Signature) -> Vec<DataValue> {
assert!(self.0.len() >= signature.returns.len());
let mut returns = Vec::with_capacity(signature.returns.len());
// Extract the returned values from this vector.
for (slot, param) in self.0.iter().zip(&signature.returns) {
let value = unsafe { DataValue::read_value_from(slot, param.value_type) };
returns.push(value);
}
returns
}
}
/// Build the Cranelift IR for moving the memory-allocated [DataValue]s to their correct location
/// (e.g. register, stack) prior to calling a [CompiledFunction]. The [Function] returned by
/// [make_trampoline] is compiled to a [Trampoline]. Note that this uses the [TargetIsa]'s default
/// calling convention so we must also check that the [CompiledFunction] has the same calling
/// convention (see [TestFileCompiler::compile]).
fn make_trampoline(name: UserFuncName, signature: &ir::Signature, isa: &dyn TargetIsa) -> Function {
// Create the trampoline signature: (callee_address: pointer, values_vec: pointer) -> ()
let pointer_type = isa.pointer_type();
let mut wrapper_sig = ir::Signature::new(isa.frontend_config().default_call_conv);
wrapper_sig.params.push(ir::AbiParam::new(pointer_type)); // Add the `callee_address` parameter.
wrapper_sig.params.push(ir::AbiParam::new(pointer_type)); // Add the `values_vec` parameter.
let mut func = ir::Function::with_name_signature(name, wrapper_sig);
// The trampoline has a single block filled with loads, one call to callee_address, and some loads.
let mut builder_context = FunctionBuilderContext::new();
let mut builder = FunctionBuilder::new(&mut func, &mut builder_context);
let block0 = builder.create_block();
builder.append_block_params_for_function_params(block0);
builder.switch_to_block(block0);
builder.seal_block(block0);
// Extract the incoming SSA values.
let (callee_value, values_vec_ptr_val) = {
let params = builder.func.dfg.block_params(block0);
(params[0], params[1])
};
// Load the argument values out of `values_vec`.
let callee_args = signature
.params
.iter()
.enumerate()
.map(|(i, param)| {
// Calculate the type to load from memory, using integers for booleans (no encodings).
let ty = param.value_type.coerce_bools_to_ints();
// We always store vector types in little-endian byte order as DataValue.
let mut flags = ir::MemFlags::trusted();
if param.value_type.is_vector() {
flags.set_endianness(ir::Endianness::Little);
}
// Load the value.
let loaded = builder.ins().load(
ty,
flags,
values_vec_ptr_val,
(i * UnboxedValues::SLOT_SIZE) as i32,
);
// For booleans, we want to type-convert the loaded integer into a boolean and ensure
// that we are using the architecture's canonical boolean representation (presumably
// comparison will emit this).
if param.value_type.is_bool() {
let b = builder.ins().icmp_imm(IntCC::NotEqual, loaded, 0);
// icmp_imm always produces a `b1`, `bextend` it if we need a larger bool
if param.value_type.bits() > 1 {
builder.ins().bextend(param.value_type, b)
} else {
b
}
} else if param.value_type.is_bool_vector() {
let zero_constant = builder.func.dfg.constants.insert(vec![0; 16].into());
let zero_vec = builder.ins().vconst(ty, zero_constant);
builder.ins().icmp(IntCC::NotEqual, loaded, zero_vec)
} else {
loaded
}
})
.collect::<Vec<_>>();
// Call the passed function.
let new_sig = builder.import_signature(signature.clone());
let call = builder
.ins()
.call_indirect(new_sig, callee_value, &callee_args);
// Store the return values into `values_vec`.
let results = builder.func.dfg.inst_results(call).to_vec();
for ((i, value), param) in results.iter().enumerate().zip(&signature.returns) {
// Before storing return values, we convert booleans to their integer representation.
let value = if param.value_type.lane_type().is_bool() {
let ty = param.value_type.lane_type().as_int();
builder.ins().bint(ty, *value)
} else {
*value
};
// We always store vector types in little-endian byte order as DataValue.
let mut flags = ir::MemFlags::trusted();
if param.value_type.is_vector() {
flags.set_endianness(ir::Endianness::Little);
}
// Store the value.
builder.ins().store(
flags,
value,
values_vec_ptr_val,
(i * UnboxedValues::SLOT_SIZE) as i32,
);
}
builder.ins().return_(&[]);
builder.finalize();
func
}
#[cfg(test)]
mod test {
use super::*;
use cranelift_reader::{parse_functions, parse_test, ParseOptions};
fn parse(code: &str) -> Function {
parse_functions(code).unwrap().into_iter().nth(0).unwrap()
}
#[test]
fn nop() {
let code = String::from(
"
test run
function %test() -> b8 {
block0:
nop
v1 = bconst.b8 true
return v1
}",
);
// extract function
let test_file = parse_test(code.as_str(), ParseOptions::default()).unwrap();
assert_eq!(1, test_file.functions.len());
let function = test_file.functions[0].0.clone();
// execute function
let mut compiler = TestFileCompiler::with_default_host_isa().unwrap();
compiler.declare_function(&function).unwrap();
compiler.define_function(function.clone()).unwrap();
compiler.create_trampoline_for_function(&function).unwrap();
let compiled = compiler.compile().unwrap();
let trampoline = compiled.get_trampoline(&function).unwrap();
let returned = trampoline.call(&[]);
assert_eq!(returned, vec![DataValue::B(true)])
}
#[test]
fn trampolines() {
let function = parse(
"
function %test(f32, i8, i64x2, b1) -> f32x4, b64 {
block0(v0: f32, v1: i8, v2: i64x2, v3: b1):
v4 = vconst.f32x4 [0x0.1 0x0.2 0x0.3 0x0.4]
v5 = bconst.b64 true
return v4, v5
}",
);
let compiler = TestFileCompiler::with_default_host_isa().unwrap();
let trampoline = make_trampoline(
UserFuncName::user(0, 0),
&function.signature,
compiler.module.isa(),
);
assert!(format!("{}", trampoline).ends_with(
"sig0 = (f32, i8, i64x2, b1) -> f32x4, b64 fast
block0(v0: i64, v1: i64):
v2 = load.f32 notrap aligned v1
v3 = load.i8 notrap aligned v1+16
v4 = load.i64x2 notrap aligned little v1+32
v5 = load.i8 notrap aligned v1+48
v6 = icmp_imm ne v5, 0
v7, v8 = call_indirect sig0, v0(v2, v3, v4, v6)
store notrap aligned little v7, v1
v9 = bint.i64 v8
store notrap aligned v9, v1+16
return
}
"
));
}
}