From 6f168571675819d153663c7258504deaa50f85f7 Mon Sep 17 00:00:00 2001 From: Petr Hosek Date: Mon, 27 Feb 2017 22:49:37 +0000 Subject: [PATCH] [AddressSanitizer] Put shadow at 0 for Fuchsia The Fuchsia ASan runtime reserves the low part of the address space. Patch by Roland McGrath Differential Revision: https://reviews.llvm.org/D30426 llvm-svn: 296405 --- llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp index 5b719a5bd1f2..afcf86547c78 100644 --- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp +++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp @@ -394,6 +394,7 @@ static ShadowMapping getShadowMapping(Triple &TargetTriple, int LongSize, TargetTriple.getArch() == llvm::Triple::mips64el; bool IsAArch64 = TargetTriple.getArch() == llvm::Triple::aarch64; bool IsWindows = TargetTriple.isOSWindows(); + bool IsFuchsia = TargetTriple.isOSFuchsia(); ShadowMapping Mapping; @@ -414,7 +415,11 @@ static ShadowMapping getShadowMapping(Triple &TargetTriple, int LongSize, else Mapping.Offset = kDefaultShadowOffset32; } else { // LongSize == 64 - if (IsPPC64) + // Fuchsia is always PIE, which means that the beginning of the address + // space is always available. + if (IsFuchsia) + Mapping.Offset = 0; + else if (IsPPC64) Mapping.Offset = kPPC64_ShadowOffset64; else if (IsSystemZ) Mapping.Offset = kSystemZ_ShadowOffset64;