wasmer_compiler_llvm/
config.rs

1use crate::compiler::LLVMCompiler;
2pub use inkwell::OptimizationLevel as LLVMOptLevel;
3use inkwell::targets::{
4    CodeModel, InitializationConfig, RelocMode, Target as InkwellTarget, TargetMachine,
5    TargetMachineOptions, TargetTriple,
6};
7use itertools::Itertools;
8use std::fs::File;
9use std::io::{self, Write};
10use std::path::PathBuf;
11use std::sync::Arc;
12use std::{fmt::Debug, num::NonZero};
13use target_lexicon::BinaryFormat;
14use wasmer_compiler::misc::{CompiledKind, function_kind_to_filename};
15use wasmer_compiler::{Compiler, CompilerConfig, Engine, EngineBuilder, ModuleMiddleware};
16use wasmer_types::{
17    Features,
18    target::{Architecture, OperatingSystem, Target, Triple},
19};
20
21/// The InkWell ModuleInfo type
22pub type InkwellModule<'ctx> = inkwell::module::Module<'ctx>;
23
24/// The InkWell MemoryBuffer type
25pub type InkwellMemoryBuffer = inkwell::memory_buffer::MemoryBuffer;
26
27/// Callbacks to the different LLVM compilation phases.
28#[derive(Debug, Clone)]
29pub struct LLVMCallbacks {
30    debug_dir: PathBuf,
31}
32
33impl LLVMCallbacks {
34    pub fn new(debug_dir: PathBuf) -> Result<Self, io::Error> {
35        // Create the debug dir in case it doesn't exist
36        std::fs::create_dir_all(&debug_dir)?;
37        Ok(Self { debug_dir })
38    }
39
40    fn base_path(&self, module_hash: &Option<String>) -> PathBuf {
41        let mut path = self.debug_dir.clone();
42        if let Some(hash) = module_hash {
43            path.push(hash);
44        }
45        std::fs::create_dir_all(&path)
46            .unwrap_or_else(|_| panic!("cannot create debug directory: {}", path.display()));
47        path
48    }
49
50    pub fn preopt_ir(
51        &self,
52        kind: &CompiledKind,
53        module_hash: &Option<String>,
54        module: &InkwellModule,
55    ) {
56        let mut path = self.base_path(module_hash);
57        path.push(function_kind_to_filename(kind, ".preopt.ll"));
58        module
59            .print_to_file(&path)
60            .expect("Error while dumping pre optimized LLVM IR");
61    }
62    pub fn postopt_ir(
63        &self,
64        kind: &CompiledKind,
65        module_hash: &Option<String>,
66        module: &InkwellModule,
67    ) {
68        let mut path = self.base_path(module_hash);
69        path.push(function_kind_to_filename(kind, ".postopt.ll"));
70        module
71            .print_to_file(&path)
72            .expect("Error while dumping post optimized LLVM IR");
73    }
74    pub fn obj_memory_buffer(
75        &self,
76        kind: &CompiledKind,
77        module_hash: &Option<String>,
78        memory_buffer: &InkwellMemoryBuffer,
79    ) {
80        let mut path = self.base_path(module_hash);
81        path.push(function_kind_to_filename(kind, ".o"));
82        let mem_buf_slice = memory_buffer.as_slice();
83        let mut file =
84            File::create(path).expect("Error while creating debug object file from LLVM IR");
85        file.write_all(mem_buf_slice).unwrap();
86    }
87
88    pub fn asm_memory_buffer(
89        &self,
90        kind: &CompiledKind,
91        module_hash: &Option<String>,
92        asm_memory_buffer: &InkwellMemoryBuffer,
93    ) {
94        let mut path = self.base_path(module_hash);
95        path.push(function_kind_to_filename(kind, ".s"));
96        let mem_buf_slice = asm_memory_buffer.as_slice();
97        let mut file =
98            File::create(path).expect("Error while creating debug assembly file from LLVM IR");
99        file.write_all(mem_buf_slice).unwrap();
100    }
101}
102
103#[derive(Debug, Clone)]
104pub struct LLVM {
105    pub(crate) enable_nan_canonicalization: bool,
106    pub(crate) enable_verifier: bool,
107    pub(crate) enable_perfmap: bool,
108    pub(crate) opt_level: LLVMOptLevel,
109    is_pic: bool,
110    pub(crate) callbacks: Option<LLVMCallbacks>,
111    /// The middleware chain.
112    pub(crate) middlewares: Vec<Arc<dyn ModuleMiddleware>>,
113    /// Number of threads to use when compiling a module.
114    pub(crate) num_threads: NonZero<usize>,
115    pub(crate) verbose_asm: bool,
116}
117
118impl LLVM {
119    /// Creates a new configuration object with the default configuration
120    /// specified.
121    pub fn new() -> Self {
122        Self {
123            enable_nan_canonicalization: false,
124            enable_verifier: false,
125            enable_perfmap: false,
126            opt_level: LLVMOptLevel::Aggressive,
127            is_pic: false,
128            callbacks: None,
129            middlewares: vec![],
130            verbose_asm: false,
131            num_threads: std::thread::available_parallelism().unwrap_or(NonZero::new(1).unwrap()),
132        }
133    }
134
135    /// The optimization levels when optimizing the IR.
136    pub fn opt_level(&mut self, opt_level: LLVMOptLevel) -> &mut Self {
137        self.opt_level = opt_level;
138        self
139    }
140
141    pub fn num_threads(&mut self, num_threads: NonZero<usize>) -> &mut Self {
142        self.num_threads = num_threads;
143        self
144    }
145
146    pub fn verbose_asm(&mut self, verbose_asm: bool) -> &mut Self {
147        self.verbose_asm = verbose_asm;
148        self
149    }
150
151    /// Callbacks that will triggered in the different compilation
152    /// phases in LLVM.
153    pub fn callbacks(&mut self, callbacks: Option<LLVMCallbacks>) -> &mut Self {
154        self.callbacks = callbacks;
155        self
156    }
157
158    fn reloc_mode(&self, binary_format: BinaryFormat) -> RelocMode {
159        if matches!(binary_format, BinaryFormat::Macho) {
160            return RelocMode::Static;
161        }
162
163        if self.is_pic {
164            RelocMode::PIC
165        } else {
166            RelocMode::Static
167        }
168    }
169
170    fn code_model(&self, binary_format: BinaryFormat) -> CodeModel {
171        // We normally use the large code model, but when targeting shared
172        // objects, we are required to use PIC. If we use PIC anyways, we lose
173        // any benefit from large code model and there's some cost on all
174        // platforms, plus some platforms (MachO) don't support PIC + large
175        // at all.
176        if matches!(binary_format, BinaryFormat::Macho) {
177            return CodeModel::Default;
178        }
179
180        if self.is_pic {
181            CodeModel::Small
182        } else {
183            CodeModel::Large
184        }
185    }
186
187    pub(crate) fn target_operating_system(&self, target: &Target) -> OperatingSystem {
188        match target.triple().operating_system {
189            OperatingSystem::Darwin(deployment) if !self.is_pic => {
190                // LLVM detects static relocation + darwin + 64-bit and
191                // force-enables PIC because MachO doesn't support that
192                // combination. They don't check whether they're targeting
193                // MachO, they check whether the OS is set to Darwin.
194                //
195                // Since both linux and darwin use SysV ABI, this should work.
196                //  but not in the case of Aarch64, there the ABI is slightly different
197                #[allow(clippy::match_single_binding)]
198                match target.triple().architecture {
199                    Architecture::Aarch64(_) => OperatingSystem::Darwin(deployment),
200                    _ => OperatingSystem::Linux,
201                }
202            }
203            other => other,
204        }
205    }
206
207    pub(crate) fn target_binary_format(&self, target: &Target) -> target_lexicon::BinaryFormat {
208        if self.is_pic {
209            target.triple().binary_format
210        } else {
211            match self.target_operating_system(target) {
212                OperatingSystem::Darwin(_) => target_lexicon::BinaryFormat::Macho,
213                _ => target_lexicon::BinaryFormat::Elf,
214            }
215        }
216    }
217
218    fn target_triple(&self, target: &Target) -> TargetTriple {
219        let architecture = if target.triple().architecture
220            == Architecture::Riscv64(target_lexicon::Riscv64Architecture::Riscv64gc)
221        {
222            target_lexicon::Architecture::Riscv64(target_lexicon::Riscv64Architecture::Riscv64)
223        } else {
224            target.triple().architecture
225        };
226        // Hack: we're using is_pic to determine whether this is a native
227        // build or not.
228
229        let operating_system = self.target_operating_system(target);
230        let binary_format = self.target_binary_format(target);
231
232        let triple = Triple {
233            architecture,
234            vendor: target.triple().vendor.clone(),
235            operating_system,
236            environment: target.triple().environment,
237            binary_format,
238        };
239        TargetTriple::create(&triple.to_string())
240    }
241
242    /// Generates the target machine for the current target
243    pub fn target_machine(&self, target: &Target) -> TargetMachine {
244        self.target_machine_with_opt(target, true)
245    }
246
247    pub(crate) fn target_machine_with_opt(
248        &self,
249        target: &Target,
250        enable_optimization: bool,
251    ) -> TargetMachine {
252        let triple = target.triple();
253        let cpu_features = &target.cpu_features();
254
255        match triple.architecture {
256            Architecture::X86_64 | Architecture::X86_32(_) => {
257                InkwellTarget::initialize_x86(&InitializationConfig {
258                    asm_parser: true,
259                    asm_printer: true,
260                    base: true,
261                    disassembler: true,
262                    info: true,
263                    machine_code: true,
264                })
265            }
266            Architecture::Aarch64(_) => InkwellTarget::initialize_aarch64(&InitializationConfig {
267                asm_parser: true,
268                asm_printer: true,
269                base: true,
270                disassembler: true,
271                info: true,
272                machine_code: true,
273            }),
274            Architecture::Riscv64(_) | Architecture::Riscv32(_) => {
275                InkwellTarget::initialize_riscv(&InitializationConfig {
276                    asm_parser: true,
277                    asm_printer: true,
278                    base: true,
279                    disassembler: true,
280                    info: true,
281                    machine_code: true,
282                })
283            }
284            Architecture::LoongArch64 => {
285                InkwellTarget::initialize_loongarch(&InitializationConfig {
286                    asm_parser: true,
287                    asm_printer: true,
288                    base: true,
289                    disassembler: true,
290                    info: true,
291                    machine_code: true,
292                })
293            }
294            _ => unimplemented!("target {} not yet supported in Wasmer", triple),
295        }
296
297        // The CPU features formatted as LLVM strings
298        // We can safely map to gcc-like features as the CPUFeatures
299        // are compliant with the same string representations as gcc.
300        let llvm_cpu_features = cpu_features
301            .iter()
302            .map(|feature| format!("+{feature}"))
303            .join(",");
304
305        let target_triple = self.target_triple(target);
306        let llvm_target = InkwellTarget::from_triple(&target_triple).unwrap();
307        let mut llvm_target_machine_options = TargetMachineOptions::new()
308            .set_cpu(match triple.architecture {
309                Architecture::Riscv64(_) => "generic-rv64",
310                Architecture::Riscv32(_) => "generic-rv32",
311                Architecture::LoongArch64 => "generic-la64",
312                _ => "generic",
313            })
314            .set_features(match triple.architecture {
315                Architecture::Riscv64(_) => "+m,+a,+c,+d,+f",
316                Architecture::Riscv32(_) => "+m,+a,+c,+d,+f",
317                Architecture::LoongArch64 => "+f,+d",
318                _ => &llvm_cpu_features,
319            })
320            .set_level(if enable_optimization {
321                self.opt_level
322            } else {
323                LLVMOptLevel::None
324            })
325            .set_reloc_mode(self.reloc_mode(self.target_binary_format(target)))
326            .set_code_model(match triple.architecture {
327                Architecture::LoongArch64 | Architecture::Riscv64(_) | Architecture::Riscv32(_) => {
328                    CodeModel::Medium
329                }
330                _ => self.code_model(self.target_binary_format(target)),
331            });
332        if let Architecture::Riscv64(_) = triple.architecture {
333            llvm_target_machine_options = llvm_target_machine_options.set_abi("lp64d");
334        }
335        let target_machine = llvm_target
336            .create_target_machine_from_options(&target_triple, llvm_target_machine_options)
337            .unwrap();
338        target_machine.set_asm_verbosity(self.verbose_asm);
339        target_machine
340    }
341}
342
343impl CompilerConfig for LLVM {
344    /// Emit code suitable for dlopen.
345    fn enable_pic(&mut self) {
346        // TODO: although we can emit PIC, the object file parser does not yet
347        // support all the relocations.
348        self.is_pic = true;
349    }
350
351    fn enable_perfmap(&mut self) {
352        self.enable_perfmap = true
353    }
354
355    /// Whether to verify compiler IR.
356    fn enable_verifier(&mut self) {
357        self.enable_verifier = true;
358    }
359
360    fn canonicalize_nans(&mut self, enable: bool) {
361        self.enable_nan_canonicalization = enable;
362    }
363
364    /// Transform it into the compiler.
365    fn compiler(self: Box<Self>) -> Box<dyn Compiler> {
366        Box::new(LLVMCompiler::new(*self))
367    }
368
369    /// Pushes a middleware onto the back of the middleware chain.
370    fn push_middleware(&mut self, middleware: Arc<dyn ModuleMiddleware>) {
371        self.middlewares.push(middleware);
372    }
373
374    fn supported_features_for_target(&self, _target: &Target) -> wasmer_types::Features {
375        let mut feats = Features::default();
376        feats.exceptions(true);
377        feats.relaxed_simd(true);
378        feats
379    }
380}
381
382impl Default for LLVM {
383    fn default() -> LLVM {
384        Self::new()
385    }
386}
387
388impl From<LLVM> for Engine {
389    fn from(config: LLVM) -> Self {
390        EngineBuilder::new(config).engine()
391    }
392}
wasmer_compiler_llvm/config.rs

wasmer_compiler_llvm/
config.rs
