[clang] Implement address sanitizer on AIX (1/3)

The PR includes clang changes needed for the address sanitizer on AIX. Will also post llvm and
compiler-rt PRs following this.

Author: jakeegan

clang/include/clang/Basic/DiagnosticDriverKinds.td

@@ -257,6 +257,8 @@ def err_drv_malformed_sanitizer_metadata_ignorelist : Error<
   "malformed sanitizer metadata ignorelist: '%0'">;
 def err_drv_unsupported_static_sanitizer_darwin : Error<
   "static %0 runtime is not supported on darwin">;
+def err_drv_unsupported_shared_sanitizer_aix : Error<
+  "shared %0 runtime is not supported on AIX">;
 def err_drv_duplicate_config : Error<
   "no more than one option '--config' is allowed">;
 def err_drv_cannot_open_config_file : Error<

clang/include/clang/Driver/Options.td

@@ -1542,7 +1542,7 @@ defm xl_pragma_pack : BoolFOption<"xl-pragma-pack",
           "Enable IBM XL #pragma pack handling">,
   NegFlag<SetFalse>>;
 def shared_libsan : Flag<["-"], "shared-libsan">,
-  HelpText<"Dynamically link the sanitizer runtime">;
+  HelpText<"Dynamically link the sanitizer runtime (Not supported for ASan on AIX)">;
 def static_libsan : Flag<["-"], "static-libsan">,
   HelpText<"Statically link the sanitizer runtime (Not supported for ASan, TSan or UBSan on darwin)">;
 def : Flag<["-"], "shared-libasan">, Alias<shared_libsan>;

clang/lib/CodeGen/BackendUtil.cpp

@@ -275,13 +275,14 @@ static bool asanUseGlobalsGC(const Triple &T, const CodeGenOptions &CGOpts) {
     return !CGOpts.DisableIntegratedAS;
   case Triple::GOFF:
     llvm::report_fatal_error("ASan not implemented for GOFF");
-  case Triple::XCOFF:
-    llvm::report_fatal_error("ASan not implemented for XCOFF.");
   case Triple::Wasm:
   case Triple::DXContainer:
   case Triple::SPIRV:
   case Triple::UnknownObjectFormat:
     break;
+  case Triple::XCOFF:
+    // FIXME: try to enable GC-friendly instrumentation for globals on AIX.
+    return false;
   }
   return false;
 }

clang/lib/Driver/ToolChain.cpp

@@ -749,7 +749,7 @@ std::string ToolChain::buildCompilerRTBasename(const llvm::opt::ArgList &Args,
   case ToolChain::FT_Shared:
     Suffix = TT.isOSWindows()
                  ? (TT.isWindowsGNUEnvironment() ? ".dll.a" : ".lib")
-                 : ".so";
+                 : (TT.isOSAIX() ? ".a" : ".so");
     break;
   }
 

clang/lib/Driver/ToolChains/AIX.cpp

@@ -20,6 +20,7 @@
 #include <set>
 
 using AIX = clang::driver::toolchains::AIX;
+using namespace clang;
 using namespace clang::driver;
 using namespace clang::driver::tools;
 using namespace clang::driver::toolchains;
@@ -233,6 +234,44 @@ void aix::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   // Specify linker input file(s).
   AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs, JA);
 
+  // Add sanitizer libraries.
+  const SanitizerArgs &Sanitize = ToolChain.getSanitizerArgs(Args);
+  const char *sanitizer = nullptr;
+  bool NeedsSanitizerDeps = false;
+  // For now, only support address sanitizer.
+  if (Sanitize.needsAsanRt())
+    sanitizer = "AddressSanitizer";
+
+  if (sanitizer) {
+    if (Sanitize.needsSharedRt()) {
+      ToolChain.getDriver().Diag(diag::err_drv_unsupported_shared_sanitizer_aix) << sanitizer;
+      return;
+    }
+    NeedsSanitizerDeps = addSanitizerRuntimes(ToolChain, Args, CmdArgs);
+  }
+
+  // Add sanitizer runtime dependencies.
+  if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles,
+                   options::OPT_shared, options::OPT_r)) {
+    if (NeedsSanitizerDeps)
+      linkSanitizerRuntimeDeps(ToolChain, Args, CmdArgs);
+  }
+
+  // We won't add the static sanitizer libraries to the DSO, but we will
+  // introduce the undefined sanitizer symbols like __asan_init to the DSO. On
+  // AIX, this undefined sanitizer symbol cannot pass final link. Add the
+  // import file to make these undefined symbols be resolved at runtime.
+  if (Args.hasArg(options::OPT_shared) &&
+      ToolChain.getSanitizerArgs(Args).needsAsanRt()) {
+    CmdArgs.push_back(
+        Args.MakeArgString(Twine("-bI:") + ToolChain.getCompilerRTPath() +
+                           "/asan.link_with_main_exec.txt"));
+    if (ToolChain.getSanitizerArgs(Args).linkCXXRuntimes())
+      CmdArgs.push_back(
+          Args.MakeArgString(Twine("-bI:") + ToolChain.getCompilerRTPath() +
+                             "/asan_cxx.link_with_main_exec.txt"));
+  }
+
   if (D.isUsingLTO()) {
     assert(!Inputs.empty() && "Must have at least one input.");
     // Find the first filename InputInfo object.
@@ -590,6 +629,12 @@ ToolChain::RuntimeLibType AIX::GetDefaultRuntimeLibType() const {
   return ToolChain::RLT_CompilerRT;
 }
 
+SanitizerMask AIX::getSupportedSanitizers() const {
+  SanitizerMask Res = ToolChain::getSupportedSanitizers();
+  Res |= SanitizerKind::Address;
+  return Res;
+}
+
 auto AIX::buildAssembler() const -> Tool * { return new aix::Assembler(*this); }
 
 auto AIX::buildLinker() const -> Tool * { return new aix::Linker(*this); }

clang/lib/Driver/ToolChains/AIX.h

@@ -98,6 +98,8 @@ class LLVM_LIBRARY_VISIBILITY AIX : public ToolChain {
     return llvm::DebuggerKind::DBX;
   }
 
+  SanitizerMask getSupportedSanitizers() const override;
+
 protected:
   Tool *buildAssembler() const override;
   Tool *buildLinker() const override;

clang/lib/Driver/ToolChains/CommonArgs.cpp

@@ -1395,6 +1395,19 @@ static bool addSanitizerDynamicList(const ToolChain &TC, const ArgList &Args,
   // the option, so don't try to pass it.
   if (TC.getTriple().isOSSolaris() && !LinkerIsGnuLd)
     return true;
+
+  if (TC.getTriple().isOSAIX()) {
+    SmallString<128> SanRTSymbolList;
+    (Twine(TC.getCompilerRTPath()) + "/" + Sanitizer +
+     ".link_with_main_exec.txt")
+        .toVector(SanRTSymbolList);
+    if (llvm::sys::fs::exists(SanRTSymbolList)) {
+      CmdArgs.push_back(Args.MakeArgString(Twine("-bE:") + SanRTSymbolList));
+      return true;
+    }
+    return false;
+  }
+
   SmallString<128> SanRT(TC.getCompilerRT(Args, Sanitizer));
   if (llvm::sys::fs::exists(SanRT + ".syms")) {
     CmdArgs.push_back(Args.MakeArgString("--dynamic-list=" + SanRT + ".syms"));
@@ -1429,7 +1442,9 @@ void tools::linkSanitizerRuntimeDeps(const ToolChain &TC,
                                      ArgStringList &CmdArgs) {
   // Force linking against the system libraries sanitizers depends on
   // (see PR15823 why this is necessary).
-  addAsNeededOption(TC, Args, CmdArgs, false);
+  // AIX does not support any --as-needed options.
+  if (!TC.getTriple().isOSAIX())
+    addAsNeededOption(TC, Args, CmdArgs, false);
   // There's no libpthread or librt on RTEMS & Android.
   if (TC.getTriple().getOS() != llvm::Triple::RTEMS &&
       !TC.getTriple().isAndroid() && !TC.getTriple().isOHOSFamily()) {
@@ -1453,6 +1468,9 @@ void tools::linkSanitizerRuntimeDeps(const ToolChain &TC,
   if (TC.getTriple().isOSLinux() && !TC.getTriple().isAndroid() &&
       !TC.getTriple().isMusl())
     CmdArgs.push_back("-lresolv");
+
+  if (TC.getTriple().isOSAIX())
+    CmdArgs.push_back("-latomic");
 }
 
 static void
@@ -1508,7 +1526,8 @@ collectSanitizerRuntimes(const ToolChain &TC, const ArgList &Args,
     StaticRuntimes.push_back("stats_client");
 
   // Always link the static runtime regardless of DSO or executable.
-  if (SanArgs.needsAsanRt())
+  // Don't see a reason that AIX needs asan_static library though.
+  if (SanArgs.needsAsanRt() && !TC.getTriple().isOSAIX())
     HelperStaticRuntimes.push_back("asan_static");
 
   // Collect static runtimes.
@@ -1642,7 +1661,9 @@ bool tools::addSanitizerRuntimes(const ToolChain &TC, const ArgList &Args,
     addSanitizerRuntime(TC, Args, CmdArgs, RT, false, true);
   bool AddExportDynamic = false;
   for (auto RT : StaticRuntimes) {
-    addSanitizerRuntime(TC, Args, CmdArgs, RT, false, true);
+    // AIX does not support --whole-archive.
+    addSanitizerRuntime(TC, Args, CmdArgs, RT, false,
+                        !TC.getTriple().isOSAIX());
     AddExportDynamic |= !addSanitizerDynamicList(TC, Args, CmdArgs, RT);
   }
   for (auto RT : NonWholeStaticRuntimes) {
@@ -1651,8 +1672,13 @@ bool tools::addSanitizerRuntimes(const ToolChain &TC, const ArgList &Args,
   }
   // If there is a static runtime with no dynamic list, force all the symbols
   // to be dynamic to be sure we export sanitizer interface functions.
-  if (AddExportDynamic)
-    CmdArgs.push_back("--export-dynamic");
+  if (AddExportDynamic) {
+    if (!TC.getTriple().isOSAIX())
+      CmdArgs.push_back("--export-dynamic");
+    else
+      llvm::report_fatal_error("Sanitizer interface functions must be exported "
+                               "by export files on AIX.");
+  }
 
   if (SanArgs.hasCrossDsoCfi() && !AddExportDynamic)
     CmdArgs.push_back("--export-dynamic-symbol=__cfi_check");

clang/test/Driver/Inputs/resource_dir/lib/aix/asan.link_with_main_exec.txt

@@ -1216,3 +1216,107 @@
 // CHECK-DSO-SHARED-HWASAN-AARCH64-LINUX-NOT: "-lresolv"
 // CHECK-DSO-SHARED-HWASAN-AARCH64-LINUX-NOT: "--export-dynamic"
 // CHECK-DSO-SHARED-HWASAN-AARCH64-LINUX-NOT: "--dynamic-list"
+
+// RUN: %clang -fsanitize=address -### %s 2>&1 \
+// RUN:     --target=powerpc-unknown-aix \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/aix_ppc_tree \
+// RUN:   | FileCheck --check-prefixes=CHECK-ASAN-LINK-RUNTIME-AIX,CHECK-ASAN-LINK-RUNTIME-AIX32 %s
+//
+// RUN: %clang -fsanitize=address -### %s 2>&1 \
+// RUN:     --target=powerpc64-unknown-aix \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/aix_ppc_tree \
+// RUN:   | FileCheck --check-prefixes=CHECK-ASAN-LINK-RUNTIME-AIX,CHECK-ASAN-LINK-RUNTIME-AIX64 %s
+//
+// RUN: %clang --driver-mode=g++ -fsanitize=address -### %s 2>&1 \
+// RUN:     --target=powerpc-unknown-aix \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/aix_ppc_tree \
+// RUN:   | FileCheck --check-prefixes=CHECK-ASAN-LINK-RUNTIME-AIX,CHECK-ASAN-LINK-RUNTIME-AIX32,CHECK-ASAN-LINK-RUNTIME-AIXCXX32,CHECK-ASAN-LINK-RUNTIME-AIXCXX %s
+//
+// RUN: %clang --driver-mode=g++ -fsanitize=address -### %s 2>&1 \
+// RUN:     --target=powerpc64-unknown-aix \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/aix_ppc_tree \
+// RUN:   | FileCheck --check-prefixes=CHECK-ASAN-LINK-RUNTIME-AIX,CHECK-ASAN-LINK-RUNTIME-AIX64,CHECK-ASAN-LINK-RUNTIME-AIXCXX64,CHECK-ASAN-LINK-RUNTIME-AIXCXX %s
+//
+// RUN: %clang -fsanitize=address -### %s 2>&1 \
+// RUN:     -static-libsan --target=powerpc-unknown-aix \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/aix_ppc_tree \
+// RUN:   | FileCheck --check-prefixes=CHECK-ASAN-LINK-RUNTIME-AIX,CHECK-ASAN-LINK-RUNTIME-AIX32 %s
+//
+// RUN: %clang -fsanitize=address -### %s 2>&1 \
+// RUN:     -static-libsan --target=powerpc64-unknown-aix \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/aix_ppc_tree \
+// RUN:   | FileCheck --check-prefixes=CHECK-ASAN-LINK-RUNTIME-AIX,CHECK-ASAN-LINK-RUNTIME-AIX64 %s
+//
+// CHECK-ASAN-LINK-RUNTIME-AIX: "{{.*}}ld{{(.exe)?}}"
+// CHECK-ASAN-LINK-RUNTIME-AIX32: "-b32"
+// CHECK-ASAN-LINK-RUNTIME-AIX64: "-b64"
+// CHECK-ASAN-LINK-RUNTIME-AIX: "-bcdtors:all:0:s"
+// CHECK-ASAN-LINK-RUNTIME-AIX32: "{{.*}}libclang_rt.asan-powerpc.a"
+// CHECK-ASAN-LINK-RUNTIME-AIX64: "{{.*}}libclang_rt.asan-powerpc64.a"
+// CHECK-ASAN-LINK-RUNTIME-AIX: "-bE:{{.*}}asan.link_with_main_exec.txt"
+// CHECK-ASAN-LINK-RUNTIME-AIXCXX32: "{{.*}}libclang_rt.asan_cxx-powerpc.a"
+// CHECK-ASAN-LINK-RUNTIME-AIXCXX64: "{{.*}}libclang_rt.asan_cxx-powerpc64.a"
+// CHECK-ASAN-LINK-RUNTIME-AIXCXX: "-bE:{{.*}}asan_cxx.link_with_main_exec.txt"
+// CHECK-ASAN-LINK-RUNTIME-AIX: "-lpthread"
+// CHECK-ASAN-LINK-RUNTIME-AIX: "-latomic"
+// CHECK-ASAN-LINK-RUNTIME-AIX: "-lunwind"
+// CHECK-ASAN-LINK-RUNTIME-AIX: "-lc"
+
+// RUN: not %clang -fsanitize=address -### %s 2>&1 \
+// RUN:     -shared-libsan --target=powerpc-unknown-aix \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/aix_ppc_tree \
+// RUN:   | FileCheck --check-prefixes=CHECK-SHARED-ASAN-AIX %s
+//
+// RUN: not %clang -fsanitize=address -### %s 2>&1 \
+// RUN:     -shared-libsan --target=powerpc64-unknown-aix \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/aix_ppc_tree \
+// RUN:   | FileCheck --check-prefixes=CHECK-SHARED-ASAN-AIX %s
+//
+// CHECK-SHARED-ASAN-AIX: {{.*}}error: shared AddressSanitizer runtime is not supported on AIX
+
+// RUN: %clang -fsanitize=address -shared -### %s 2>&1 \
+// RUN:     --target=powerpc-unknown-aix \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/aix_ppc_tree \
+// RUN:   | FileCheck --check-prefixes=CHECK-ASAN-SHARED-LIBRARY-AIX,CHECK-ASAN-SHARED-LIBRARY-AIX32 %s
+//
+// RUN: %clang -fsanitize=address -shared -### %s 2>&1 \
+// RUN:     --target=powerpc64-unknown-aix \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/aix_ppc_tree \
+// RUN:   | FileCheck --check-prefixes=CHECK-ASAN-SHARED-LIBRARY-AIX,CHECK-ASAN-SHARED-LIBRARY-AIX64 %s
+//
+// RUN: %clang -fsanitize=address --driver-mode=g++ -shared -### %s 2>&1 \
+// RUN:     --target=powerpc-unknown-aix \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/aix_ppc_tree \
+// RUN:   | FileCheck --check-prefixes=CHECK-ASAN-SHARED-LIBRARY-AIX,CHECK-ASAN-SHARED-LIBRARY-AIX32,CHECK-ASAN-SHARED-LIBRARY-AIXCXX %s
+//
+// RUN: %clang -fsanitize=address --driver-mode=g++ -shared -### %s 2>&1 \
+// RUN:     --target=powerpc64-unknown-aix \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     --sysroot=%S/Inputs/aix_ppc_tree \
+// RUN:   | FileCheck --check-prefixes=CHECK-ASAN-SHARED-LIBRARY-AIX,CHECK-ASAN-SHARED-LIBRARY-AIX64,CHECK-ASAN-SHARED-LIBRARY-AIXCXX %s
+//
+// CHECK-ASAN-SHARED-LIBRARY-AIX: "{{.*}}ld{{(.exe)?}}"
+// CHECK-ASAN-SHARED-LIBRARY-AIX32: "-b32"
+// CHECK-ASAN-SHARED-LIBRARY-AIX64: "-b64"
+// CHECK-ASAN-SHARED-LIBRARY-AIX: "-bcdtors:all:0:s"
+// CHECK-ASAN-SHARED-LIBRARY-AIX: "-bI:{{.*}}asan.link_with_main_exec.txt"
+// CHECK-ASAN-SHARED-LIBRARY-AIXCXX: "-bI:{{.*}}asan_cxx.link_with_main_exec.txt"
+// CHECK-ASAN-SHARED-LIBRARY-AIX32-NOT: "{{.*}}libclang_rt.asan-powerpc.a"
+// CHECK-ASAN-SHARED-LIBRARY-AIX64-NOT: "{{.*}}libclang_rt.asan-powerpc64.a"
+// CHECK-ASAN-SHARED-LIBRARY-AIXCXX-NOT: "{{.*}}libclang_rt.asan_cxx-powerpc{{.*}}"
+// CHECK-ASAN-SHARED-LIBRARY-AIX-NOT: "-lpthread"
+// CHECK-ASAN-SHARED-LIBRARY-AIX-NOT: "-latomic"
+// CHECK-ASAN-SHARED-LIBRARY-AIX: "-lunwind"
+// CHECK-ASAN-SHARED-LIBRARY-AIX: "-lc"
+