[Clang][Sanitizers] Enable NSAN on X86_64 only

[alexander-shaposhnikov]

This is a follow-up to #93783.
The current set of patches covers only x86_64,
therefore we should not enable this flag on arm64 yet.

[llvmbot]

@llvm/pr-subscribers-clang-driver

@llvm/pr-subscribers-clang

Author: Alexander Shaposhnikov (alexander-shaposhnikov)

Changes

This is a follow-up to #93783.
The current set of patches covers only x86_64 (in particular, on compiler-rt's side),
therefore we should now enable this flag on arm64.

---

Full diff: https://github.com/llvm/llvm-project/pull/95885.diff

3 Files Affected:

• (modified) clang/lib/Driver/ToolChains/Darwin.cpp (+3-1)
• (modified) clang/lib/Driver/ToolChains/Linux.cpp (+1-1)
• (modified) clang/test/Driver/fsanitize.c (+4-4)

diff --git a/clang/lib/Driver/ToolChains/Darwin.cpp b/clang/lib/Driver/ToolChains/Darwin.cpp
index f742db7668cd2..0ae356ca91b22 100644
--- a/clang/lib/Driver/ToolChains/Darwin.cpp
+++ b/clang/lib/Driver/ToolChains/Darwin.cpp
@@ -3457,7 +3457,6 @@ SanitizerMask Darwin::getSupportedSanitizers() const {
   Res |= SanitizerKind::PointerCompare;
   Res |= SanitizerKind::PointerSubtract;
   Res |= SanitizerKind::Leak;
-  Res |= SanitizerKind::NumericalStability;
   Res |= SanitizerKind::Fuzzer;
   Res |= SanitizerKind::FuzzerNoLink;
   Res |= SanitizerKind::ObjCCast;
@@ -3474,6 +3473,9 @@ SanitizerMask Darwin::getSupportedSanitizers() const {
        isTargetTvOSSimulator() || isTargetWatchOSSimulator())) {
     Res |= SanitizerKind::Thread;
   }
+
+  if (IsX86_64)
+    Res |= SanitizerKind::NumericalStability;
   return Res;
 }
 
diff --git a/clang/lib/Driver/ToolChains/Linux.cpp b/clang/lib/Driver/ToolChains/Linux.cpp
index 2222dea431c3c..49e029e7c9ab7 100644
--- a/clang/lib/Driver/ToolChains/Linux.cpp
+++ b/clang/lib/Driver/ToolChains/Linux.cpp
@@ -826,7 +826,7 @@ SanitizerMask Linux::getSupportedSanitizers() const {
   if (IsX86_64 || IsAArch64) {
     Res |= SanitizerKind::KernelHWAddress;
   }
-  if (IsX86_64 || IsAArch64)
+  if (IsX86_64)
     Res |= SanitizerKind::NumericalStability;
 
   // Work around "Cannot represent a difference across sections".
diff --git a/clang/test/Driver/fsanitize.c b/clang/test/Driver/fsanitize.c
index 08e9c78f9d1d2..db14f6e195c64 100644
--- a/clang/test/Driver/fsanitize.c
+++ b/clang/test/Driver/fsanitize.c
@@ -462,8 +462,8 @@
 // RUN: %clang --target=x86_64-linux-gnu -fsanitize=numerical %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-NSAN-X86-64-LINUX
 // CHECK-NSAN-X86-64-LINUX: "-fsanitize=numerical"
 
-// RUN: %clang --target=aarch64-unknown-linux-gnu -fsanitize=numerical %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-NSAN-AARCH64-LINUX
-// CHECK-NSAN-AARCH64-LINUX: "-fsanitize=numerical"
+// RUN: not %clang --target=aarch64-unknown-linux-gnu -fsanitize=numerical %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-NSAN-AARCH64-LINUX
+// CHECK-NSAN-AARCH64-LINUX: error: unsupported option '-fsanitize=numerical' for target 'aarch64-unknown-linux-gnu'
 
 // RUN: not %clang --target=mips-unknown-linux -fsanitize=numerical %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-NSAN-MIPS-LINUX
 // CHECK-NSAN-MIPS-LINUX: error: unsupported option '-fsanitize=numerical' for target 'mips-unknown-linux'
@@ -471,8 +471,8 @@
 // RUN: %clang --target=x86_64-apple-macos -fsanitize=numerical %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-NSAN-X86-64-MACOS
 // CHECK-NSAN-X86-64-MACOS: "-fsanitize=numerical"
 
-// RUN: %clang --target=arm64-apple-macos -fsanitize=numerical %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-NSAN-ARM64-MACOS
-// CHECK-NSAN-ARM64-MACOS: "-fsanitize=numerical"
+// RUN: not %clang --target=arm64-apple-macos -fsanitize=numerical %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-NSAN-ARM64-MACOS
+// CHECK-NSAN-ARM64-MACOS: error: unsupported option '-fsanitize=numerical' for target 'arm64-apple-macos'
 
 // RUN: %clang --target=x86_64-apple-darwin -fsanitize=thread %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-TSAN-X86-64-DARWIN
 // CHECK-TSAN-X86-64-DARWIN-NOT: unsupported option

[MaskRay]

If the code is generic, it might already work on aarch64... It seems sufficient to avoid compiler-rt runtime testing.

[alexander-shaposhnikov]

~90% of the functionality would work on aarch64, but there are a few x86_64-specific quirks (__float128, x86-64-specific assumptions about long double in the helper routines) that need to be refactored (beyond my current bandwidth).

[MaskRay]

~90% of the functionality would work on aarch64, but there are a few x86_64-specific quirks (__float128, x86-64-specific assumptions about long double in the helper routines) that need to be refactored (beyond my current bandwidth).

I am happy to investigate them. I guess we don't need to exclude driver now? xray compiler instrumentation works for Mach-O but the runtime is not yet, we don't disable the driver for Mach-O

[alexander-shaposhnikov]

yeah, but I kind of wanted to be defensive - people will try the tool and I wanted to avoid any potential confusions / overpromises.