[sanitizer] Split GetMaxVirtualAddress into separate Linux version and Mac version [NFC]

The logic in GetMaxVirtualAddress is already pretty complex, and I want to get rid of the hardcoded value for iOS/AArch64, which would need adding more Darwin-specific code, so let's split the implementation into sanitizer_linux.cc and sanitizer_mac.cc files. NFC.

Differential Revision: https://reviews.llvm.org/D35031



git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@307281 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 14 insertions, 0 deletions

diff --git a/lib/sanitizer_common/sanitizer_mac.cc b/lib/sanitizer_common/sanitizer_mac.cc
index 2a13fee05..7d027130d 100644
--- a/lib/sanitizer_common/sanitizer_mac.cc
+++ b/lib/sanitizer_common/sanitizer_mac.cc
@@ -800,6 +800,20 @@ char **GetArgv() {
   return *_NSGetArgv();
 }
 
+uptr GetMaxVirtualAddress() {
+#if SANITIZER_WORDSIZE == 64
+# if defined(__aarch64__) && SANITIZER_IOS && !SANITIZER_IOSSIM
+  // Ideally, we would derive the upper bound from MACH_VM_MAX_ADDRESS. The
+  // upper bound can change depending on the device.
+  return 0x200000000 - 1;
+# else
+  return (1ULL << 47) - 1;  // 0x00007fffffffffffUL;
+# endif
+#else  // SANITIZER_WORDSIZE == 32
+  return (1ULL << 32) - 1;  // 0xffffffff;
+#endif  // SANITIZER_WORDSIZE
+}
+
 uptr FindAvailableMemoryRange(uptr shadow_size,
                               uptr alignment,
                               uptr left_padding) {