re PR go/56173 (Several libgo tests FAIL on Solaris/SPARC)

	PR go/56173
crypto/md5: fix for big-endian processors

From-SVN: r195867

diff --git a/libgo/go/crypto/md5/md5block.go b/libgo/go/crypto/md5/md5block.go
index 59f8f6f5afa42ce9c1fda4fec947465bb83807c0..0ca42177403c30565caab6b9ed900faacf3bc29b 100644 (file)
--- a/libgo/go/crypto/md5/md5block.go
+++ b/libgo/go/crypto/md5/md5block.go
@@ -5,6 +5,16 @@ import (
        "unsafe"
 )
 
+const x86 = runtime.GOARCH == "amd64" || runtime.GOARCH == "386"
+
+var littleEndian bool
+
+func init() {
+       x := uint32(0x04030201)
+       y := [4]byte{0x1, 0x2, 0x3, 0x4}
+       littleEndian = *(*[4]byte)(unsafe.Pointer(&x)) == y
+}
+
 func block(dig *digest, p []byte) {
        a := dig.s[0]
        b := dig.s[1]
@@ -16,13 +26,13 @@ func block(dig *digest, p []byte) {
                aa, bb, cc, dd := a, b, c, d
 
                // This is a constant condition - it is not evaluated on each iteration.
-               if runtime.GOARCH == "amd64" || runtime.GOARCH == "386" {
+               if x86 {
                        // MD5 was designed so that x86 processors can just iterate
                        // over the block data directly as uint32s, and we generate
                        // less code and run 1.3x faster if we take advantage of that.
                        // My apologies.
                        X = (*[16]uint32)(unsafe.Pointer(&p[0]))
-               } else if uintptr(unsafe.Pointer(&p[0]))&(unsafe.Alignof(uint32(0))-1) == 0 {
+               } else if littleEndian && uintptr(unsafe.Pointer(&p[0]))&(unsafe.Alignof(uint32(0))-1) == 0 {
                        X = (*[16]uint32)(unsafe.Pointer(&p[0]))
                } else {
                        X = &xbuf