Add Polly support. Use can be triggered via -Z polly, when rustc uses an LLVM which includes polly.

Force LLVM rebuild on buildbots.

Author: DiamondLovesYou

config.toml.example

@@ -303,6 +303,10 @@
 #optimize-tests = true
 #debuginfo-tests = true
 
+# Flag indicating whether tests are optimized with Polly. If optimize-tests is false,
+# polly-tests will be false regardless of its value here.
+#polly-tests = false
+
 # Flag indicating whether codegen tests will be run or not. If you get an error
 # saying that the FileCheck executable is missing, you may want to disable this.
 #codegen-tests = true
@@ -346,6 +350,10 @@
 # Whether to deny warnings in crates
 #deny-warnings = true
 
+# Use Polly on the rust compiler itself. If optimize is false, this will be
+# false as well.
+#polly-self = false
+
 # =============================================================================
 # Options for specific targets
 #

src/bootstrap/bin/rustc.rs

@@ -91,6 +91,7 @@ fn main() {
         ("RUSTC_REAL", "RUSTC_LIBDIR")
     };
     let stage = env::var("RUSTC_STAGE").expect("RUSTC_STAGE was not set");
+    let stage = usize::from_str(stage.as_str()).expect("RUSTC_STAGE not a usize");
     let sysroot = env::var_os("RUSTC_SYSROOT").expect("RUSTC_SYSROOT was not set");
     let on_fail = env::var_os("RUSTC_ON_FAIL").map(|of| Command::new(of));
 
@@ -152,7 +153,7 @@ fn main() {
         // workaround undefined references to `rust_eh_unwind_resume` generated
         // otherwise, see issue https://github.com/rust-lang/rust/issues/43095.
         if crate_name == "panic_abort" ||
-           crate_name == "compiler_builtins" && stage != "0" {
+           crate_name == "compiler_builtins" && stage != 0 {
             cmd.arg("-C").arg("panic=abort");
         }
 
@@ -267,6 +268,14 @@ fn main() {
         cmd.arg("--cfg").arg("parallel_queries");
     }
 
+    let use_polly = match env::var("RUSTC_USE_POLLY") {
+        Ok(v) => v != "0",
+        Err(_) => false,
+    };
+    if use_polly && stage >= 1 {
+        cmd.arg("-Z").arg("polly");
+    }
+
     let color = match env::var("RUSTC_COLOR") {
         Ok(s) => usize::from_str(&s).expect("RUSTC_COLOR should be an integer"),
         Err(_) => 0,

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

@@ -36,7 +36,7 @@ use native;
 use tool;
 
 use cache::{INTERNER, Interned};
-use builder::{Step, RunConfig, ShouldRun, Builder};
+use builder::{Step, RunConfig, ShouldRun, Builder, Kind};
 
 #[derive(Debug, PartialOrd, Ord, Copy, Clone, PartialEq, Eq, Hash)]
 pub struct Std {
@@ -553,6 +553,18 @@ pub fn rustc_cargo_env(builder: &Builder, cargo: &mut Command) {
     if builder.config.rustc_parallel_queries {
         cargo.env("RUSTC_PARALLEL_QUERIES", "1");
     }
+
+    let use_polly = match builder.kind {
+        Kind::Test | Kind::Check => {
+            builder.config.rust_polly_tests
+        },
+        _ => builder.config.rust_polly_self
+    };
+    if use_polly {
+        cargo.env("RUSTC_USE_POLLY", "1");
+    } else {
+        cargo.env("RUSTC_USE_POLLY", "0");
+    }
 }
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]

src/bootstrap/config.rs

@@ -99,10 +99,12 @@ pub struct Config {
     pub rustc_parallel_queries: bool,
     pub rustc_default_linker: Option<String>,
     pub rust_optimize_tests: bool,
+    pub rust_polly_tests: bool,
     pub rust_debuginfo_tests: bool,
     pub rust_dist_src: bool,
     pub rust_codegen_backends: Vec<Interned<String>>,
     pub rust_codegen_backends_dir: String,
+    pub rust_polly_self: bool,
 
     pub build: Interned<String>,
     pub hosts: Vec<Interned<String>>,
@@ -294,6 +296,7 @@ struct Rust {
     rpath: Option<bool>,
     optimize_tests: Option<bool>,
     debuginfo_tests: Option<bool>,
+    polly_tests: Option<bool>,
     codegen_tests: Option<bool>,
     ignore_git: Option<bool>,
     debug: Option<bool>,
@@ -306,6 +309,7 @@ struct Rust {
     wasm_syscall: Option<bool>,
     lld: Option<bool>,
     deny_warnings: Option<bool>,
+    polly_self: Option<bool>,
 }
 
 /// TOML representation of how each build target is configured.
@@ -515,6 +519,10 @@ impl Config {
             ignore_git = rust.ignore_git;
             debug_jemalloc = rust.debug_jemalloc;
             set(&mut config.rust_optimize_tests, rust.optimize_tests);
+            set(&mut config.rust_polly_tests, rust.polly_tests);
+            if !config.rust_optimize_tests {
+                config.rust_polly_tests = false;
+            }
             set(&mut config.rust_debuginfo_tests, rust.debuginfo_tests);
             set(&mut config.codegen_tests, rust.codegen_tests);
             set(&mut config.rust_rpath, rust.rpath);
@@ -545,6 +553,10 @@ impl Config {
                 Some(n) => config.rust_codegen_units = Some(n),
                 None => {}
             }
+
+            config.rust_polly_self = rust
+              .polly_self
+              .unwrap_or(false);
         }
 
         if let Some(ref t) = toml.target {
@@ -602,6 +614,10 @@ impl Config {
         config.rust_debug_assertions = debug_assertions.unwrap_or(default);
         config.rust_optimize = optimize.unwrap_or(!default);
 
+        if !config.rust_optimize {
+          config.rust_polly_self = false;
+        }
+
         let default = config.channel == "dev";
         config.ignore_git = ignore_git.unwrap_or(default);
 

src/bootstrap/test.rs

@@ -960,6 +960,9 @@ impl Step for Compiletest {
         }
         flags.push("-Zunstable-options".to_string());
         flags.push(builder.config.cmd.rustc_args().join(" "));
+        if builder.config.rust_polly_self {
+            flags.push("-Zpolly".into());
+        }
 
         if let Some(linker) = builder.linker(target) {
             cmd.arg("--linker").arg(linker);

src/librustc/session/config.rs

@@ -1293,6 +1293,8 @@ options! {DebuggingOptions, DebuggingSetter, basic_debugging_options,
           "make the current crate share its generic instantiations"),
     chalk: bool = (false, parse_bool, [TRACKED],
           "enable the experimental Chalk-based trait solving engine"),
+    polly: bool = (false, parse_bool, [UNTRACKED], "Run the Polly polyhedral \
+           model optimization passes."),
 }
 
 pub fn default_lib_output() -> CrateType {

src/librustc_llvm/build.rs

@@ -157,11 +157,53 @@ fn main() {
         cfg.define("LLVM_RUSTLLVM", None);
     }
 
+    let (enable_polly, polly_link_kind, polly_link_isl) = {
+        let mut cmd = Command::new(&llvm_config);
+        cmd.arg("--libdir");
+        let libdir = output(&mut cmd);
+        let libdir = libdir.lines().next().unwrap();
+        let libdir = Path::new(&libdir);
+        assert!(libdir.exists());
+
+        // We can't specify the full libname to rust, so the linker will always expect (on unix)
+        // LLVMPolly to be libLLVMPolly, which won't be present. I didn't realize this fact until
+        // after I wrote the following, but maybe this issue will be resolved in the future.
+        let allow_shared = false;
+        let mut found_static = false;
+        let mut found_shared = false;
+        for entry in libdir.read_dir().unwrap() {
+            if let Ok(entry) = entry {
+                if let Some(name) = entry.path().file_name() {
+                    let name = name.to_str().unwrap();
+                    if name.contains("Polly") {
+                        if !found_static {
+                            found_static = !name.contains("LLVM");
+                        }
+                        if !found_shared {
+                            found_shared = name.contains("LLVM");
+                        }
+                    }
+                }
+            }
+        }
+
+        let found_static = found_static;
+        let found_shared = allow_shared && found_shared;
+        let enabled = found_static || found_shared;
+        let (kind, isl) = match (found_static, found_shared) {
+            (false, false) => ("", false),
+            (true, _) => ("static", true),
+            (false, true) => ("dylib", false),
+        };
+        (enabled, kind, isl)
+    };
+
     build_helper::rerun_if_changed_anything_in_dir(Path::new("../rustllvm"));
     cfg.file("../rustllvm/PassWrapper.cpp")
        .file("../rustllvm/RustWrapper.cpp")
        .file("../rustllvm/ArchiveWrapper.cpp")
        .file("../rustllvm/Linker.cpp")
+       .define("ENABLE_POLLY", if enable_polly { "1" } else { "0" })
        .cpp(true)
        .cpp_link_stdlib(None) // we handle this below
        .compile("rustllvm");
@@ -214,6 +256,20 @@ fn main() {
         println!("cargo:rustc-link-lib={}={}", kind, name);
     }
 
+    if enable_polly {
+        match polly_link_kind {
+            "dylib" => {
+                panic!("dynamically linking polly is not possible :(");
+                //println!("cargo:rustc-flags=-l:LLVMPolly")
+            },
+            _ => println!("cargo:rustc-link-lib={}=Polly", polly_link_kind),
+        }
+
+        if polly_link_isl {
+            println!("cargo:rustc-link-lib={}=PollyISL", polly_link_kind);
+        }
+    }
+
     // 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);