rewrite pgo-gen-lto to rmake

src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -20,7 +20,6 @@ run-make/min-global-align/Makefile
 run-make/native-link-modifier-bundle/Makefile
 run-make/no-alloc-shim/Makefile
 run-make/pdb-buildinfo-cl-cmd/Makefile
-run-make/pgo-gen-lto/Makefile
 run-make/pgo-indirect-call-promotion/Makefile
 run-make/raw-dylib-alt-calling-convention/Makefile
 run-make/raw-dylib-c/Makefile

tests/run-make/pgo-gen-lto/Makefile

@@ -1,11 +0,0 @@
-# needs-profiler-support
-# ignore-cross-compile
-
-include ../tools.mk
-
-COMPILE_FLAGS=-Copt-level=3 -Clto=fat -Cprofile-generate="$(TMPDIR)"
-
-all:
-	$(RUSTC) $(COMPILE_FLAGS) test.rs
-	$(call RUN,test) || exit 1
-	[ -e "$(TMPDIR)"/default_*.profraw ] || (echo "No .profraw file"; exit 1)

tests/run-make/pgo-gen-lto/rmake.rs

@@ -0,0 +1,22 @@
+// A simple smoke test: when rustc compiles with profiling enabled, a profraw file
+// should be generated.
+// See https://github.com/rust-lang/rust/pull/48346
+
+//@ needs-profiler-support
+// Reason: this exercises LTO profiling
+//@ ignore-cross-compile
+// Reason: the compiled binary is executed
+
+use run_make_support::{cwd, has_extension, has_prefix, run, rustc, shallow_find_files};
+
+fn main() {
+    rustc().opt_level("3").arg("-Clto=fat").profile_generate(cwd()).input("test.rs").run();
+    run("test");
+    assert_eq!(
+        shallow_find_files(cwd(), |path| {
+            has_prefix(path, "default_") && has_extension(path, "profraw")
+        })
+        .len(),
+        1
+    );
+}