[PATCH] [MSan] [MIPS] Adding support for MIPS64

[Kostya Serebryany]

================
Comment at: lib/msan/msan.cc:510
@@ -509,2 +509,3 @@
 
 static void* get_tls_base() {
+  // as this is only relevant for architecture supporting msandr
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eugenis@, maybe we should simply drop this code? 

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Comment at: lib/msan/msan_linux.cc:38
@@ -37,1 +37,3 @@
 
+#if defined(__mips64__) && (SANITIZER_WORDSIZE == 64)
+static const uptr kMemBeg     = 0xe000000000;
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Why do you use 
  #if defined(__mips64__) && (SANITIZER_WORDSIZE == 64)
here and just 
  #if defined(__mips64__)
elsewhere? 

Does __mips64__ imply SANITIZER_WORDSIZE == 64?
If so, just use __mips64__

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Comment at: lib/sanitizer_common/sanitizer_allocator.h:475
@@ +474,3 @@
+  // to have kRegionSize >= 2^32
+  COMPILER_CHECK((kRegionSize) >= (1ULL << (40 / 2)));
+#else
----------------
Did you already verify that this actually works?
For a 40-bit address space you may need to use SanitizerAllocator32 instead.

http://reviews.llvm.org/D5906