[asan][hwasan] Add config for AArch64 Linux with 39-bit VA.

[efriedma-quic]

This is leveraging work which has already been done for Android, which ships 39-bit VA kernels, and extending it to other embedded Linux targets.

(Marking draft while we complete internal testing.)

[github-actions]

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You can test this locally with the following command:

git-clang-format --diff origin/main HEAD --extensions h -- compiler-rt/lib/asan/asan_allocator.h compiler-rt/lib/hwasan/hwasan_allocator.h --diff_from_common_commit

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View the diff from clang-format here.

diff --git a/compiler-rt/lib/asan/asan_allocator.h b/compiler-rt/lib/asan/asan_allocator.h
index e2ec87769..779813724 100644
--- a/compiler-rt/lib/asan/asan_allocator.h
+++ b/compiler-rt/lib/asan/asan_allocator.h
@@ -200,7 +200,8 @@ const uptr kAllocatorSpace = ~(uptr)0;
 #    if defined(__powerpc64__)
 const uptr kAllocatorSize  =  0x20000000000ULL;  // 2T.
 typedef DefaultSizeClassMap SizeClassMap;
-#    elif defined(__aarch64__) && (SANITIZER_ANDROID || defined(SANITIZER_AARCH64_39BIT_VA))
+#    elif defined(__aarch64__) && \
+        (SANITIZER_ANDROID || defined(SANITIZER_AARCH64_39BIT_VA))
 // Android needs to support 39, 42 and 48 bit VMA.
 const uptr kAllocatorSize  =  0x2000000000ULL;  // 128G.
 typedef VeryCompactSizeClassMap SizeClassMap;
diff --git a/compiler-rt/lib/hwasan/hwasan_allocator.h b/compiler-rt/lib/hwasan/hwasan_allocator.h
index 94fd7b2f7..b539e446a 100644
--- a/compiler-rt/lib/hwasan/hwasan_allocator.h
+++ b/compiler-rt/lib/hwasan/hwasan_allocator.h
@@ -74,7 +74,8 @@ struct AP64 {
 #if defined(HWASAN_ALIASING_MODE)
   static const uptr kSpaceSize = 1ULL << kAddressTagShift;
   typedef __sanitizer::DefaultSizeClassMap SizeClassMap;
-#elif SANITIZER_LINUX && !SANITIZER_ANDROID && !defined(SANITIZER_AARCH64_39BIT_VA)
+#elif SANITIZER_LINUX && !SANITIZER_ANDROID && \
+    !defined(SANITIZER_AARCH64_39BIT_VA)
   static const uptr kSpaceSize = 0x40000000000ULL;  // 4T.
   typedef __sanitizer::DefaultSizeClassMap SizeClassMap;
 #else

[thurstond]

Thanks for this patch!

Even though it's a small patch, please split it into three parts (compiler-rt, asan, hwasan). e.g., if you implement 39-bit VMA AArch64 support for MSan, it's strange to need a "[asan][hwasan]" patch as a prerequisite. Smaller patches are also easier to debug (e.g., for the HWASan-only patch, we can rule out its impact on any ASan buildbot breakage).

[efriedma-quic]

I can see two patches... not sure about three: the change to compiler-rt/CMakeLists.txt is a no-op on its own.

[thurstond]

I can see two patches... not sure about three: the change to compiler-rt/CMakeLists.txt is a no-op on its own.

It's good to split off NFC portions of patches.