Initial project import

tools/v/vlib/runtime/runtime.v

@@ -0,0 +1,62 @@
+// Copyright (c) 2019-2024 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+
+module runtime
+
+import os
+
+// nr_jobs returns the same as `nr_cpus`, but influenced by the env variable `VJOBS`.
+// If the environment variable `VJOBS` is set, and has a value > 0,
+// then `nr_jobs` will return that number instead.
+// This is useful for runtime tweaking of e.g. threaded or concurrent code.
+pub fn nr_jobs() int {
+	$if cross ? {
+		// A single thread is *more likely* to work consistently everywhere during bootstrapping.
+		// NB: the compiler itself uses runtime.nr_jobs() and sync.pool to process things in parallel
+		// in its cgen stage. Returning 1 here, increases the chances of it working on non linux systems.
+		return 1
+	}
+	mut cpus := nr_cpus()
+	// allow for overrides, for example using `VJOBS=32 ./v test .`
+	vjobs := os.getenv('VJOBS').int()
+	if vjobs > 0 {
+		cpus = vjobs
+	}
+	if cpus == 0 {
+		return 1
+	}
+	return cpus
+}
+
+// is_32bit returns true if the current executable is running on a 32 bit system.
+pub fn is_32bit() bool {
+	$if x32 {
+		return true
+	}
+	return false
+}
+
+// is_64bit returns true if the current executable is running on a 64 bit system.
+pub fn is_64bit() bool {
+	$if x64 {
+		return true
+	}
+	return false
+}
+
+// is_little_endian returns true if the current executable is running on a little-endian system.
+pub fn is_little_endian() bool {
+	$if little_endian {
+		return true
+	}
+	return false
+}
+
+// is_big_endian returns true if the current executable is running on a big-endian system.
+pub fn is_big_endian() bool {
+	$if big_endian {
+		return true
+	}
+	return false
+}