[compiler-rt] 54a1e05 - [asan][AIX] Set allocator size and beginning (#144784)

[via llvm-commits]

Author: Jake Egan
Date: 2026-01-09T12:49:45-05:00
New Revision: 54a1e05d3c5eac476a0b14d2d7a712c7ece2c255

URL: https://github.com/llvm/llvm-project/commit/54a1e05d3c5eac476a0b14d2d7a712c7ece2c255
DIFF: https://github.com/llvm/llvm-project/commit/54a1e05d3c5eac476a0b14d2d7a712c7ece2c255.diff

LOG: [asan][AIX] Set allocator size and beginning (#144784)

On 64-bit AIX, set allocator size to 256G and set beginning to
0x0a00000000000000.

Issue: #138916

---------

Co-authored-by: Hubert Tong <hubert.reinterpretcast at gmail.com>

Added: 
    

Modified: 
    compiler-rt/lib/asan/asan_allocator.h
    compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary32.h
    compiler-rt/lib/sanitizer_common/sanitizer_platform.h

Removed: 
    


################################################################################
diff  --git a/compiler-rt/lib/asan/asan_allocator.h b/compiler-rt/lib/asan/asan_allocator.h
index 7798137246cf4..4131fda096930 100644
--- a/compiler-rt/lib/asan/asan_allocator.h
+++ b/compiler-rt/lib/asan/asan_allocator.h
@@ -198,7 +198,11 @@ const uptr kAllocatorSpace = ~(uptr)0;
 #    endif  // SANITIZER_APPLE
 
 #    if defined(__powerpc64__)
+#      if SANITIZER_AIX
+const uptr kAllocatorSize = 1ULL << 38;  // 256G.
+#      else
 const uptr kAllocatorSize  =  0x20000000000ULL;  // 2T.
+#      endif
 typedef DefaultSizeClassMap SizeClassMap;
 #    elif defined(__aarch64__) && \
         (SANITIZER_ANDROID || defined(SANITIZER_AARCH64_39BIT_VA))

diff  --git a/compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary32.h b/compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary32.h
index 602b197c42ae3..0faf9b3c151a4 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary32.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary32.h
@@ -288,6 +288,7 @@ class SizeClassAllocator32 {
   uptr ComputeRegionId(uptr mem) const {
     if (SANITIZER_SIGN_EXTENDED_ADDRESSES)
       mem &= (kSpaceSize - 1);
+    mem -= kSpaceBeg;
     const uptr res = mem >> kRegionSizeLog;
     CHECK_LT(res, kNumPossibleRegions);
     return res;

diff  --git a/compiler-rt/lib/sanitizer_common/sanitizer_platform.h b/compiler-rt/lib/sanitizer_common/sanitizer_platform.h
index 1b47f3e24d12d..acd2da26117c3 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_platform.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_platform.h
@@ -319,7 +319,11 @@
 #endif
 
 // The first address that can be returned by mmap.
-#define SANITIZER_MMAP_BEGIN 0
+#if SANITIZER_AIX && SANITIZER_WORDSIZE == 64
+#  define SANITIZER_MMAP_BEGIN 0x0a00'0000'0000'0000ULL
+#else
+#  define SANITIZER_MMAP_BEGIN 0
+#endif
 
 // The range of addresses which can be returned my mmap.
 // FIXME: this value should be 
diff erent on 
diff erent platforms.  Larger values