diff --git a/clang/docs/AddressSanitizer.rst b/clang/docs/AddressSanitizer.rst --- a/clang/docs/AddressSanitizer.rst +++ b/clang/docs/AddressSanitizer.rst @@ -276,6 +276,18 @@ `_ for more details. +Code generation control +======================= + +Instrumentation code outlining +------------------------------ + +By default AddressSanitizer inlines the instumentation code to improve the +run-time performance, which leads to increased binary size. Using the +(clang flag ``-fsanitize-address-outline-instrumentation` default: ``false``) +flag forces all code instumentation to be outlined, which reduces the size +of the binary, but also reduces the run-time performace. + Limitations =========== diff --git a/clang/docs/UsersManual.rst b/clang/docs/UsersManual.rst --- a/clang/docs/UsersManual.rst +++ b/clang/docs/UsersManual.rst @@ -1649,6 +1649,14 @@ Enable simple code coverage in addition to certain sanitizers. See :doc:`SanitizerCoverage` for more details. +**-f[no-]sanitize-address-outline-instrumentation** + + Controls how address sanitizer code is generated. If enabled will always use + a function call instead of inlining the code. Turning this option on could + reduce the binary size, but might result in a worse run-time performance. + + See :doc: `AddressSanitizer` for more details. + **-f[no-]sanitize-stats** Enable simple statistics gathering for the enabled sanitizers. diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td --- a/clang/include/clang/Driver/Options.td +++ b/clang/include/clang/Driver/Options.td @@ -1558,6 +1558,12 @@ Group, Flags<[CoreOption, NoXarchOption]>, HelpText<"Disable origins tracking in MemorySanitizer">; +def fsanitize_address_outline_instrumentation : Flag<["-"], "fsanitize-address-outline-instrumentation">, + Group, + HelpText<"Always generate function calls for address sanitizer instrumentation">; +def fno_sanitize_address_outline_instrumentation : Flag<["-"], "fno-sanitize-address-outline-instrumentation">, + Group, + HelpText<"Use default code inlining logic for the address sanitizer">; def fsanitize_hwaddress_experimental_aliasing : Flag<["-"], "fsanitize-hwaddress-experimental-aliasing">, Group, diff --git a/clang/include/clang/Driver/SanitizerArgs.h b/clang/include/clang/Driver/SanitizerArgs.h --- a/clang/include/clang/Driver/SanitizerArgs.h +++ b/clang/include/clang/Driver/SanitizerArgs.h @@ -44,6 +44,7 @@ bool AsanUseOdrIndicator = false; bool AsanInvalidPointerCmp = false; bool AsanInvalidPointerSub = false; + bool AsanOutlineInstrumentation = false; llvm::AsanDtorKind AsanDtorKind = llvm::AsanDtorKind::Invalid; std::string HwasanAbi; bool LinkRuntimes = true; diff --git a/clang/lib/Driver/SanitizerArgs.cpp b/clang/lib/Driver/SanitizerArgs.cpp --- a/clang/lib/Driver/SanitizerArgs.cpp +++ b/clang/lib/Driver/SanitizerArgs.cpp @@ -805,6 +805,11 @@ options::OPT_fno_sanitize_address_poison_custom_array_cookie, AsanPoisonCustomArrayCookie); + AsanOutlineInstrumentation = + Args.hasFlag(options::OPT_fsanitize_address_outline_instrumentation, + options::OPT_fno_sanitize_address_outline_instrumentation, + AsanOutlineInstrumentation); + // As a workaround for a bug in gold 2.26 and earlier, dead stripping of // globals in ASan is disabled by default on ELF targets. // See https://sourceware.org/bugzilla/show_bug.cgi?id=19002 @@ -1118,6 +1123,11 @@ CmdArgs.push_back("-asan-detect-invalid-pointer-sub"); } + if (AsanOutlineInstrumentation) { + CmdArgs.push_back("-mllvm"); + CmdArgs.push_back("-asan-instrumentation-with-call-threshold=0"); + } + // Only pass the option to the frontend if the user requested, // otherwise the frontend will just use the codegen default. if (AsanDtorKind != llvm::AsanDtorKind::Invalid) { diff --git a/clang/test/CodeGen/asan-use-callbacks.cpp b/clang/test/CodeGen/asan-use-callbacks.cpp new file mode 100644 --- /dev/null +++ b/clang/test/CodeGen/asan-use-callbacks.cpp @@ -0,0 +1,12 @@ +// RUN: %clang -S -fsanitize=address -emit-llvm -o - -fsanitize=address %s \ +// RUN: | FileCheck %s --check-prefixes=CHECK-NO-OUTLINE +// RUN: %clang -S -fsanitize=address -emit-llvm -o - -fsanitize=address %s \ +// RUN: -fsanitize-address-outline-instrumentation \ +// RUN: | FileCheck %s --check-prefixes=CHECK-OUTLINE + +// CHECK-NO-OUTLINE-NOT: call{{.*}}@__asan_load4 +// CHECK-OUTLINE: call{{.*}}@__asan_load4 + +int deref(int *p) { + return *p; +} diff --git a/clang/test/Driver/fsanitize.c b/clang/test/Driver/fsanitize.c --- a/clang/test/Driver/fsanitize.c +++ b/clang/test/Driver/fsanitize.c @@ -247,6 +247,20 @@ // CHECK-ASAN-GLOBALS: -cc1{{.*}}-fsanitize-address-globals-dead-stripping // CHECK-NO-ASAN-GLOBALS-NOT: -cc1{{.*}}-fsanitize-address-globals-dead-stripping +// RUN: %clang -target x86_64-linux-gnu -fsanitize-address-outline-instrumentation %s -### 2>&1 | \ +// RUN: FileCheck %s --check-prefix=CHECK-ASAN-OUTLINE-WARN +// CHECK-ASAN-OUTLINE-WARN: warning: argument unused during compilation: '-fsanitize-address-outline-instrumentation' +// RUN: %clang -target x86_64-linux-gnu -fsanitize=address -fsanitize-address-outline-instrumentation %s -### 2>&1 | \ +// RUN: FileCheck %s --check-prefix=CHECK-ASAN-OUTLINE-OK +// RUN: %clang -target x86_64-linux-gnu -fsanitize=address -fno-sanitize-address-outline-instrumentation -fsanitize-address-outline-instrumentation %s -### 2>&1 | \ +// RUN: FileCheck %s --check-prefix=CHECK-ASAN-OUTLINE-OK +// CHECK-ASAN-OUTLINE-OK: "-mllvm" "-asan-instrumentation-with-call-threshold=0" +// RUN: %clang -target x86_64-linux-gnu -fsanitize=address -fno-sanitize-address-outline-instrumentation %s -### 2>&1 | \ +// RUN: FileCheck %s --check-prefix=CHECK-NO-CHECK-ASAN-CALLBACK +// RUN: %clang -target x86_64-linux-gnu -fsanitize=address -fsanitize-address-outline-instrumentation -fno-sanitize-address-outline-instrumentation %s -### 2>&1 | \ +// RUN: FileCheck %s --check-prefix=CHECK-NO-CHECK-ASAN-CALLBACK +// CHECK-NO-CHECK-ASAN-CALLBACK-NOT: "-mllvm" "-asan-instrumentation-with-call-threshold=0" + // RUN: %clang -target x86_64-linux-gnu -fsanitize=address -fsanitize-address-use-odr-indicator %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-ASAN-ODR-INDICATOR // RUN: %clang_cl --target=x86_64-windows -fsanitize=address -fsanitize-address-use-odr-indicator -### -- %s 2>&1 | FileCheck %s --check-prefix=CHECK-ASAN-ODR-INDICATOR // CHECK-ASAN-ODR-INDICATOR: -cc1{{.*}}-fsanitize-address-use-odr-indicator