1 files changed, 55 insertions, 0 deletions
diff --git a/libgo/go/runtime/internal/sys/intrinsics.go b/libgo/go/runtime/internal/sys/intrinsics.go
new file mode 100644
index 0000000000..43acf34b80
--- /dev/null
+++ b/libgo/go/runtime/internal/sys/intrinsics.go
@@ -0,0 +1,55 @@
+// Copyright 2016 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 sys
+
+//extern __builtin_ctz
+func builtinCtz32(uint32) int32
+
+//extern __builtin_ctzll
+func builtinCtz64(uint64) int32
+
+//go:nosplit
+
+// Ctz64 counts trailing (low-order) zeroes,
+// and if all are zero, then 64.
+func Ctz64(x uint64) uint64 {
+	if x == 0 {
+		return 64
+	}
+	return uint64(builtinCtz64(x))
+}
+
+//go:nosplit
+
+// Ctz32 counts trailing (low-order) zeroes,
+// and if all are zero, then 32.
+func Ctz32(x uint32) uint32 {
+	if x == 0 {
+		return 32
+	}
+	return uint32(builtinCtz32(x))
+}
+
+//extern __builtin_bswap64
+func bswap64(uint64) uint64
+
+//go:nosplit
+
+// Bswap64 returns its input with byte order reversed
+// 0x0102030405060708 -> 0x0807060504030201
+func Bswap64(x uint64) uint64 {
+	return bswap64(x)
+}
+
+//extern __builtin_bswap32
+func bswap32(uint32) uint32
+
+//go:nosplit
+
+// Bswap32 returns its input with byte order reversed
+// 0x01020304 -> 0x04030201
+func Bswap32(x uint32) uint32 {
+	return bswap32(x)
+}