2016-05-26  Martin Sebor  <msebor@redhat.com>
	    Jakub Jelinek  <jakub@redhat.com>

	* asan/asan_rtl.cc (InitializeHighMemEnd): Backport part of upstream
	r221457 fix and typo fix from r206158.

--- libsanitizer/asan/asan_rtl.cc.jj	2013-03-04 12:44:18.000000000 +0100
+++ libsanitizer/asan/asan_rtl.cc	2016-05-26 09:57:10.761973999 +0200
@@ -308,11 +308,13 @@ static void InitializeHighMemEnd() {
 # if defined(__powerpc64__)
   // FIXME:
   // On PowerPC64 we have two different address space layouts: 44- and 46-bit.
-  // We somehow need to figure our which one we are using now and choose
+  // We somehow need to figure out which one we are using now and choose
   // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL.
   // Note that with 'ulimit -s unlimited' the stack is moved away from the top
   // of the address space, so simply checking the stack address is not enough.
-  kHighMemEnd = (1ULL << 44) - 1;  // 0x00000fffffffffffUL
+  // This should (does) work for both PowerPC64 Endian modes.
+  kHighMemEnd =
+      (1ULL << (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1)) - 1;
 # else
   kHighMemEnd = (1ULL << 47) - 1;  // 0x00007fffffffffffUL;
 # endif