More MSan/ASan annotations.

This change lets us bootstrap LLVM/Clang under ASan and MSan. It contains
fixes for 2 issues:

- X86JIT reads return address from stack, which MSan does not know is
  initialized.
- bugpoint tests run binaries with RLIMIT_AS. This does not work with certain
  Sanitizers.

We are no longer including config.h in Compiler.h with this change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174306 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 10 insertions, 2 deletions

diff --git a/lib/Support/Allocator.cpp b/lib/Support/Allocator.cpp
index b4fdc1e1bc..e269cf997a 100644
--- a/lib/Support/Allocator.cpp
+++ b/lib/Support/Allocator.cpp
@@ -104,8 +104,8 @@ void *BumpPtrAllocator::Allocate(size_t Size, size_t Alignment) {
   if (Ptr + Size <= End) {
     CurPtr = Ptr + Size;
     // Update the allocation point of this memory block in MemorySanitizer.
-    // Without this, MemorySanitizer reports for values originating from it will
-    // point to the allocation point of the entire slab.
+    // Without this, MemorySanitizer messages for values originated from here
+    // will point to the allocation of the entire slab.
     __msan_allocated_memory(Ptr, Size);
     return Ptr;
   }
diff --git a/lib/Support/Unix/Program.inc b/lib/Support/Unix/Program.inc
index c384316e20..117151c91d 100644
--- a/lib/Support/Unix/Program.inc
+++ b/lib/Support/Unix/Program.inc
@@ -17,6 +17,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "Unix.h"
+#include "llvm/Support/Compiler.h"
 #include "llvm/Support/FileSystem.h"
 #include <llvm/Config/config.h>
 #if HAVE_SYS_STAT_H
@@ -164,12 +165,16 @@ static void SetMemoryLimits (unsigned size)
   setrlimit (RLIMIT_RSS, &r);
 #endif
 #ifdef RLIMIT_AS  // e.g. NetBSD doesn't have it.
+  // Don't set virtual memory limit if built with any Sanitizer. They need 80Tb
+  // of virtual memory for shadow memory mapping.
+#if !LLVM_MEMORY_SANITIZER_BUILD && !LLVM_ADDRESS_SANITIZER_BUILD
   // Virtual memory.
   getrlimit (RLIMIT_AS, &r);
   r.rlim_cur = limit;
   setrlimit (RLIMIT_AS, &r);
 #endif
 #endif
+#endif
 }
 
 bool
diff --git a/lib/Target/X86/X86JITInfo.cpp b/lib/Target/X86/X86JITInfo.cpp
index cca391f647..0a4accee99 100644
--- a/lib/Target/X86/X86JITInfo.cpp
+++ b/lib/Target/X86/X86JITInfo.cpp
@@ -351,6 +351,9 @@ static
 void LLVM_ATTRIBUTE_USED
 X86CompilationCallback2(intptr_t *StackPtr, intptr_t RetAddr) {
   intptr_t *RetAddrLoc = &StackPtr[1];
+  // We are reading raw stack data here. Tell MemorySanitizer that it is
+  // sufficiently initialized.
+  __msan_unpoison(RetAddrLoc, sizeof(*RetAddrLoc));
   assert(*RetAddrLoc == RetAddr &&
          "Could not find return address on the stack!");