1 files changed, 76 insertions, 0 deletions
diff --git a/src/runtime/mem_darwin.go b/src/runtime/mem_darwin.go
new file mode 100644
index 0000000..ae84871
--- /dev/null
+++ b/src/runtime/mem_darwin.go
@@ -0,0 +1,76 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"unsafe"
+)
+
+// Don't split the stack as this function may be invoked without a valid G,
+// which prevents us from allocating more stack.
+//
+//go:nosplit
+func sysAllocOS(n uintptr) unsafe.Pointer {
+	v, err := mmap(nil, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
+	if err != 0 {
+		return nil
+	}
+	return v
+}
+
+func sysUnusedOS(v unsafe.Pointer, n uintptr) {
+	// MADV_FREE_REUSABLE is like MADV_FREE except it also propagates
+	// accounting information about the process to task_info.
+	madvise(v, n, _MADV_FREE_REUSABLE)
+}
+
+func sysUsedOS(v unsafe.Pointer, n uintptr) {
+	// MADV_FREE_REUSE is necessary to keep the kernel's accounting
+	// accurate. If called on any memory region that hasn't been
+	// MADV_FREE_REUSABLE'd, it's a no-op.
+	madvise(v, n, _MADV_FREE_REUSE)
+}
+
+func sysHugePageOS(v unsafe.Pointer, n uintptr) {
+}
+
+func sysNoHugePageOS(v unsafe.Pointer, n uintptr) {
+}
+
+func sysHugePageCollapseOS(v unsafe.Pointer, n uintptr) {
+}
+
+// Don't split the stack as this function may be invoked without a valid G,
+// which prevents us from allocating more stack.
+//
+//go:nosplit
+func sysFreeOS(v unsafe.Pointer, n uintptr) {
+	munmap(v, n)
+}
+
+func sysFaultOS(v unsafe.Pointer, n uintptr) {
+	mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE|_MAP_FIXED, -1, 0)
+}
+
+func sysReserveOS(v unsafe.Pointer, n uintptr) unsafe.Pointer {
+	p, err := mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE, -1, 0)
+	if err != 0 {
+		return nil
+	}
+	return p
+}
+
+const _ENOMEM = 12
+
+func sysMapOS(v unsafe.Pointer, n uintptr) {
+	p, err := mmap(v, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_FIXED|_MAP_PRIVATE, -1, 0)
+	if err == _ENOMEM {
+		throw("runtime: out of memory")
+	}
+	if p != v || err != 0 {
+		print("runtime: mmap(", v, ", ", n, ") returned ", p, ", ", err, "\n")
+		throw("runtime: cannot map pages in arena address space")
+	}
+}