Merge branch 'autopar_rebase2' into autopar_develdevel/autopar_devel

Quickly commit changes in the rebase branch.

1 files changed, 28 insertions, 0 deletions

diff --git a/libgo/go/unicode/utf8/utf8.go b/libgo/go/unicode/utf8/utf8.go
index b8368fc..ef0d740 100644
--- a/libgo/go/unicode/utf8/utf8.go
+++ b/libgo/go/unicode/utf8/utf8.go
@@ -448,6 +448,20 @@ func RuneStart(b byte) bool { return b&0xC0 != 0x80 }
 
 // Valid reports whether p consists entirely of valid UTF-8-encoded runes.
 func Valid(p []byte) bool {
+	// Fast path. Check for and skip 8 bytes of ASCII characters per iteration.
+	for len(p) >= 8 {
+		// Combining two 32 bit loads allows the same code to be used
+		// for 32 and 64 bit platforms.
+		// The compiler can generate a 32bit load for first32 and second32
+		// on many platforms. See test/codegen/memcombine.go.
+		first32 := uint32(p[0]) | uint32(p[1])<<8 | uint32(p[2])<<16 | uint32(p[3])<<24
+		second32 := uint32(p[4]) | uint32(p[5])<<8 | uint32(p[6])<<16 | uint32(p[7])<<24
+		if (first32|second32)&0x80808080 != 0 {
+			// Found a non ASCII byte (>= RuneSelf).
+			break
+		}
+		p = p[8:]
+	}
 	n := len(p)
 	for i := 0; i < n; {
 		pi := p[i]
@@ -480,6 +494,20 @@ func Valid(p []byte) bool {
 
 // ValidString reports whether s consists entirely of valid UTF-8-encoded runes.
 func ValidString(s string) bool {
+	// Fast path. Check for and skip 8 bytes of ASCII characters per iteration.
+	for len(s) >= 8 {
+		// Combining two 32 bit loads allows the same code to be used
+		// for 32 and 64 bit platforms.
+		// The compiler can generate a 32bit load for first32 and second32
+		// on many platforms. See test/codegen/memcombine.go.
+		first32 := uint32(s[0]) | uint32(s[1])<<8 | uint32(s[2])<<16 | uint32(s[3])<<24
+		second32 := uint32(s[4]) | uint32(s[5])<<8 | uint32(s[6])<<16 | uint32(s[7])<<24
+		if (first32|second32)&0x80808080 != 0 {
+			// Found a non ASCII byte (>= RuneSelf).
+			break
+		}
+		s = s[8:]
+	}
 	n := len(s)
 	for i := 0; i < n; {
 		si := s[i]