Auto merge of #50044 - DiamondLovesYou:polly, r=<try>

Add Polly support

It is always compiled and linked, but not used by default.

Use can be triggered via `-C polly=true` or at compiler build-time (see `config.toml.example`).

Author: bors

config.toml.example

@@ -346,6 +346,9 @@
 # Whether to deny warnings in crates
 #deny-warnings = true
 
+# Use polyhedral optimizations by default.
+#use-polly-by-default = false
+
 # =============================================================================
 # Options for specific targets
 #

src/bootstrap/bootstrap.py

@@ -690,6 +690,10 @@ def update_submodules(self):
             recorded_submodules[data[3]] = data[2]
         for module in filtered_submodules:
             self.update_submodule(module[0], module[1], recorded_submodules)
+        polly_path = "src/llvm/tools/polly"
+        if not os.path.exists(os.path.join(self.rust_root, polly_path)):
+            run(["git", "clone", "https://github.com/llvm-mirror/polly.git",
+                 "src/llvm/tools/polly", "-b", "release_60"])
         print("Submodules updated in %.2f seconds" % (time() - start_time))
 
     def set_dev_environment(self):

src/bootstrap/compile.rs

@@ -553,6 +553,9 @@ pub fn rustc_cargo_env(builder: &Builder, cargo: &mut Command) {
     if builder.config.rustc_parallel_queries {
         cargo.env("RUSTC_PARALLEL_QUERIES", "1");
     }
+    if builder.config.rust_codegen_polly_by_default {
+        cargo.env("RUSTC_FORCE_USE_POLLY", "1");
+    }
 }
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]

src/bootstrap/config.rs

@@ -103,6 +103,7 @@ pub struct Config {
     pub rust_dist_src: bool,
     pub rust_codegen_backends: Vec<Interned<String>>,
     pub rust_codegen_backends_dir: String,
+    pub rust_codegen_polly_by_default: bool,
 
     pub build: Interned<String>,
     pub hosts: Vec<Interned<String>>,
@@ -306,6 +307,7 @@ struct Rust {
     wasm_syscall: Option<bool>,
     lld: Option<bool>,
     deny_warnings: Option<bool>,
+    use_polly_by_default: Option<bool>,
 }
 
 /// TOML representation of how each build target is configured.
@@ -537,6 +539,10 @@ impl Config {
                 Some(n) => config.rust_codegen_units = Some(n),
                 None => {}
             }
+
+            config.rust_codegen_polly_by_default = rust
+              .use_polly_by_default
+              .unwrap_or(false);
         }
 
         if let Some(ref t) = toml.target {

src/librustc/session/config.rs

@@ -1074,6 +1074,9 @@ options! {CodegenOptions, CodegenSetter, basic_codegen_options,
         [TRACKED], "panic strategy to compile crate with"),
     incremental: Option<String> = (None, parse_opt_string, [UNTRACKED],
           "enable incremental compilation"),
+    polly: bool = (option_env!("RUSTC_FORCE_USE_POLLY").map(|_| true ).unwrap_or(false),
+                   parse_bool, [UNTRACKED], "Run the Polly polyhedral \
+           model optimization passes."),
 }
 
 options! {DebuggingOptions, DebuggingSetter, basic_debugging_options,

src/librustc_llvm/build.rs

@@ -214,6 +214,9 @@ fn main() {
         println!("cargo:rustc-link-lib={}={}", kind, name);
     }
 
+    println!("cargo:rustc-link-lib=static=Polly");
+    println!("cargo:rustc-link-lib=static=PollyISL");
+
     // LLVM ldflags
     //
     // If we're a cross-compile of LLVM then unfortunately we can't trust these

src/librustc_llvm/ffi.rs

@@ -1642,7 +1642,8 @@ extern "C" {
                                        Singlethread: bool)
                                        -> TargetMachineRef;
     pub fn LLVMRustDisposeTargetMachine(T: TargetMachineRef);
-    pub fn LLVMRustAddAnalysisPasses(T: TargetMachineRef, PM: PassManagerRef, M: ModuleRef);
+    pub fn LLVMRustAddAnalysisPasses(T: TargetMachineRef, PM: PassManagerRef, M: ModuleRef,
+                                     Polly: bool);
     pub fn LLVMRustAddBuilderLibraryInfo(PMB: PassManagerBuilderRef,
                                          M: ModuleRef,
                                          DisableSimplifyLibCalls: bool);

src/librustc_trans/back/lto.rs

@@ -460,7 +460,7 @@ fn run_pass_manager(cgcx: &CodegenContext,
     debug!("running the pass manager");
     unsafe {
         let pm = llvm::LLVMCreatePassManager();
-        llvm::LLVMRustAddAnalysisPasses(tm, pm, llmod);
+        llvm::LLVMRustAddAnalysisPasses(tm, pm, llmod, config.polly);
         let pass = llvm::LLVMRustFindAndCreatePass("verify\0".as_ptr() as *const _);
         assert!(!pass.is_null());
         llvm::LLVMRustAddPass(pm, pass);

src/librustc_trans/back/write.rs

@@ -271,6 +271,7 @@ pub struct ModuleConfig {
     no_integrated_as: bool,
     embed_bitcode: bool,
     embed_bitcode_marker: bool,
+    pub polly: bool,
 }
 
 impl ModuleConfig {
@@ -302,7 +303,8 @@ impl ModuleConfig {
             vectorize_loop: false,
             vectorize_slp: false,
             merge_functions: false,
-            inline_threshold: None
+            inline_threshold: None,
+            polly: false,
         }
     }
 
@@ -340,6 +342,8 @@ impl ModuleConfig {
 
         self.merge_functions = sess.opts.optimize == config::OptLevel::Default ||
                                sess.opts.optimize == config::OptLevel::Aggressive;
+        self.polly = sess.opts.cg.polly && !self.no_prepopulate_passes &&
+                     !sess.target.target.options.is_like_emscripten;
     }
 }
 
@@ -567,8 +571,8 @@ unsafe fn optimize(cgcx: &CodegenContext,
 
         if !config.no_verify { assert!(addpass("verify")); }
         if !config.no_prepopulate_passes {
-            llvm::LLVMRustAddAnalysisPasses(tm, fpm, llmod);
-            llvm::LLVMRustAddAnalysisPasses(tm, mpm, llmod);
+            llvm::LLVMRustAddAnalysisPasses(tm, fpm, llmod, config.polly);
+            llvm::LLVMRustAddAnalysisPasses(tm, mpm, llmod, config.polly);
             let opt_level = config.opt_level.unwrap_or(llvm::CodeGenOptLevel::None);
             with_llvm_pmb(llmod, &config, opt_level, &mut |b| {
                 llvm::LLVMPassManagerBuilderPopulateFunctionPassManager(b, fpm);
@@ -666,11 +670,12 @@ unsafe fn codegen(cgcx: &CodegenContext,
     unsafe fn with_codegen<F, R>(tm: TargetMachineRef,
                                  llmod: ModuleRef,
                                  no_builtins: bool,
+                                 polly: bool,
                                  f: F) -> R
         where F: FnOnce(PassManagerRef) -> R,
     {
         let cpm = llvm::LLVMCreatePassManager();
-        llvm::LLVMRustAddAnalysisPasses(tm, cpm, llmod);
+        llvm::LLVMRustAddAnalysisPasses(tm, cpm, llmod, polly);
         llvm::LLVMRustAddLibraryInfo(cpm, llmod, no_builtins);
         f(cpm)
     }
@@ -765,7 +770,8 @@ unsafe fn codegen(cgcx: &CodegenContext,
                 cursor.position() as size_t
             }
 
-            with_codegen(tm, llmod, config.no_builtins, |cpm| {
+            with_codegen(tm, llmod, config.no_builtins, config.polly,
+                         |cpm| {
                 llvm::LLVMRustPrintModule(cpm, llmod, out.as_ptr(), demangle_callback);
                 llvm::LLVMDisposePassManager(cpm);
             });
@@ -783,7 +789,8 @@ unsafe fn codegen(cgcx: &CodegenContext,
             } else {
                 llmod
             };
-            with_codegen(tm, llmod, config.no_builtins, |cpm| {
+            with_codegen(tm, llmod, config.no_builtins, config.polly,
+                         |cpm| {
                 write_output_file(diag_handler, tm, cpm, llmod, &path,
                                   llvm::FileType::AssemblyFile)
             })?;
@@ -794,7 +801,8 @@ unsafe fn codegen(cgcx: &CodegenContext,
         }
 
         if write_obj {
-            with_codegen(tm, llmod, config.no_builtins, |cpm| {
+            with_codegen(tm, llmod, config.no_builtins, config.polly,
+                         |cpm| {
                 write_output_file(diag_handler, tm, cpm, llmod, &obj_out,
                                   llvm::FileType::ObjectFile)
             })?;

src/rustllvm/PassWrapper.cpp

@@ -61,6 +61,11 @@ DEFINE_STDCXX_CONVERSION_FUNCTIONS(TargetMachine, LLVMTargetMachineRef)
 DEFINE_STDCXX_CONVERSION_FUNCTIONS(PassManagerBuilder,
                                    LLVMPassManagerBuilderRef)
 
+
+namespace polly {
+void initializePollyPasses(llvm::PassRegistry &Registry);
+}
+
 extern "C" void LLVMInitializePasses() {
   PassRegistry &Registry = *PassRegistry::getPassRegistry();
   initializeCore(Registry);
@@ -73,6 +78,8 @@ extern "C" void LLVMInitializePasses() {
   initializeInstCombine(Registry);
   initializeInstrumentation(Registry);
   initializeTarget(Registry);
+
+  polly::initializePollyPasses(Registry);
 }
 
 enum class LLVMRustPassKind {
@@ -415,15 +422,24 @@ extern "C" void LLVMRustDisposeTargetMachine(LLVMTargetMachineRef TM) {
   delete unwrap(TM);
 }
 
+namespace polly {
+void registerPollyPasses(llvm::legacy::PassManagerBase &PM);
+}
+
 // Unfortunately, LLVM doesn't expose a C API to add the corresponding analysis
 // passes for a target to a pass manager. We export that functionality through
 // this function.
 extern "C" void LLVMRustAddAnalysisPasses(LLVMTargetMachineRef TM,
                                           LLVMPassManagerRef PMR,
-                                          LLVMModuleRef M) {
+                                          LLVMModuleRef M,
+                                          bool Polly) {
   PassManagerBase *PM = unwrap(PMR);
   PM->add(
       createTargetTransformInfoWrapperPass(unwrap(TM)->getTargetIRAnalysis()));
+
+  if(Polly) {
+    polly::registerPollyPasses(*PM);
+  }
 }
 
 extern "C" void LLVMRustConfigurePassManagerBuilder(