Auto merge of #58508 - Zoxc:time-crate, r=oli-obk

bors · bors · commit 289b78ac0a2e · 2019-06-17T09:59:57.000Z
Add a RUSTC_TIME env var to time rust crates during bootstrap Blocked on rust-lang/cargo#6674 r? @michaelwoerister Example for rustc with #58507: ``` time: 0.460; rss: 94MB parsing time: 0.000; rss: 94MB attributes injection time: 0.000; rss: 94MB recursion limit time: 0.000; rss: 94MB crate injection time: 0.000; rss: 94MB plugin loading time: 0.000; rss: 94MB plugin registration time: 0.044; rss: 94MB pre ast expansion lint checks time: 1.999; rss: 316MB expand crate time: 0.000; rss: 316MB check unused macros time: 2.000; rss: 316MB expansion time: 0.000; rss: 316MB maybe building test harness time: 0.053; rss: 316MB AST validation time: 0.000; rss: 316MB maybe creating a macro crate time: 1.515; rss: 397MB name resolution time: 0.122; rss: 397MB complete gated feature checking time: 0.655; rss: 546MB lowering ast -> hir time: 0.136; rss: 550MB early lint checks time: 0.117; rss: 540MB validate hir map time: 0.606; rss: 540MB indexing hir time: 0.000; rss: 480MB load query result cache time: 0.000; rss: 478MB dep graph tcx init time: 0.000; rss: 478MB looking for entry point time: 0.001; rss: 478MB looking for plugin registrar time: 0.001; rss: 478MB looking for derive registrar time: 0.049; rss: 478MB loop checking time: 0.064; rss: 479MB attribute checking time: 0.166; rss: 484MB stability checking time: 0.699; rss: 566MB type collecting time: 0.006; rss: 566MB outlives testing time: 0.018; rss: 568MB impl wf inference time: 0.002; rss: 583MB unsafety checking time: 0.005; rss: 583MB orphan checking time: 0.227; rss: 583MB coherence checking time: 0.006; rss: 583MB variance testing time: 1.546; rss: 657MB wf checking time: 0.389; rss: 665MB item-types checking time: 13.999; rss: 837MB item-bodies checking time: 1.692; rss: 883MB rvalue promotion time: 0.067; rss: 883MB intrinsic checking time: 0.624; rss: 887MB match checking time: 0.246; rss: 889MB liveness checking time: 2.629; rss: 889MB misc checking time: 0.000; rss: 889MB borrow checking time: 16.754; rss: 1242MB MIR borrow checking time: 0.050; rss: 1242MB dumping chalk-like clauses time: 0.010; rss: 1242MB MIR effect checking time: 0.001; rss: 1242MB layout testing time: 0.829; rss: 1244MB privacy checking time: 0.183; rss: 1247MB death checking time: 0.100; rss: 1248MB unused lib feature checking time: 0.405; rss: 1250MB lint checking time: 1.518; rss: 1250MB misc checking time: 0.000; rss: 1250MB resolving dependency formats time: 2.928; rss: 1332MB write metadata time: 0.014; rss: 1332MB collecting roots time: 7.621; rss: 1488MB collecting mono items time: 7.635; rss: 1488MB monomorphization collection time: 0.557; rss: 1567MB codegen unit partitioning time: 27.971; rss: 2656MB codegen to LLVM IR time: 0.056; rss: 2656MB assert dep graph time: 0.000; rss: 2656MB serialize dep graph time: 195.414; rss: 2656MB codegen time: 0.000; rss: 329MB serialize work products time: 1.664; rss: 331MB running linker time: 1.965; rss: 331MB linking [RUSTC-TIMING] rustc test:false 950.103 ``` It doesn't really look like the times add up here.
diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs
@@ -93,6 +93,21 @@ fn main() {
              env::join_paths(&dylib_path).unwrap());
     let mut maybe_crate = None;
 
+    // Get the name of the crate we're compiling, if any.
+    let maybe_crate_name = args.windows(2)
+        .find(|a| &*a[0] == "--crate-name")
+        .map(|crate_name| &*crate_name[1]);
+
+    if let Some(current_crate) = maybe_crate_name {
+        if let Some(target) = env::var_os("RUSTC_TIME") {
+            if target == "all" ||
+               target.into_string().unwrap().split(",").any(|c| c.trim() == current_crate)
+            {
+                cmd.arg("-Ztime");
+            }
+        }
+    }
+
     // Non-zero stages must all be treated uniformly to avoid problems when attempting to uplift
     // compiler libraries and such from stage 1 to 2.
     if stage == "0" {
@@ -152,10 +167,7 @@ fn main() {
             cmd.arg(format!("-Clinker={}", target_linker));
         }
 
-        let crate_name = args.windows(2)
-            .find(|a| &*a[0] == "--crate-name")
-            .unwrap();
-        let crate_name = &*crate_name[1];
+        let crate_name = maybe_crate_name.unwrap();
         maybe_crate = Some(crate_name);
 
         // If we're compiling specifically the `panic_abort` crate then we pass
