[clang] ac500fd - [asan][clang] Add flag to outline instrumentation
Vitaly Buka via cfe-commits
cfe-commits at lists.llvm.org
Wed Jul 14 13:36:44 PDT 2021
Author: Kirill Stoimenov
Date: 2021-07-14T13:36:34-07:00
New Revision: ac500fd18f0615c45d9d127bfb576ffa1e11425a
URL: https://github.com/llvm/llvm-project/commit/ac500fd18f0615c45d9d127bfb576ffa1e11425a
DIFF: https://github.com/llvm/llvm-project/commit/ac500fd18f0615c45d9d127bfb576ffa1e11425a.diff
LOG: [asan][clang] Add flag to outline instrumentation
Summary This option can be used to reduce the size of the
binary. The trade-off in this case would be the run-time
performance.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D105726
Added:
clang/test/CodeGen/asan-use-callbacks.cpp
Modified:
clang/docs/AddressSanitizer.rst
clang/docs/UsersManual.rst
clang/include/clang/Driver/Options.td
clang/include/clang/Driver/SanitizerArgs.h
clang/lib/Driver/SanitizerArgs.cpp
clang/test/Driver/fsanitize.c
Removed:
################################################################################
diff --git a/clang/docs/AddressSanitizer.rst b/clang/docs/AddressSanitizer.rst
index 14f3938496c30..15ac6ff5ac850 100644
--- a/clang/docs/AddressSanitizer.rst
+++ b/clang/docs/AddressSanitizer.rst
@@ -276,6 +276,18 @@ library name in the symbolized stack trace of the leak report. See
<https://github.com/google/sanitizers/wiki/AddressSanitizerLeakSanitizer#suppressions>`_
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
index 57d53415c5807..f7f76ed3f3e20 100644
--- a/clang/docs/UsersManual.rst
+++ b/clang/docs/UsersManual.rst
@@ -1649,6 +1649,14 @@ are listed below.
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
index c15690d448843..79955f4fa4f08 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -1558,6 +1558,12 @@ def fno_sanitize_memory_track_origins : Flag<["-"], "fno-sanitize-memory-track-o
Group<f_clang_Group>,
Flags<[CoreOption, NoXarchOption]>,
HelpText<"Disable origins tracking in MemorySanitizer">;
+def fsanitize_address_outline_instrumentation : Flag<["-"], "fsanitize-address-outline-instrumentation">,
+ Group<f_clang_Group>,
+ HelpText<"Always generate function calls for address sanitizer instrumentation">;
+def fno_sanitize_address_outline_instrumentation : Flag<["-"], "fno-sanitize-address-outline-instrumentation">,
+ Group<f_clang_Group>,
+ HelpText<"Use default code inlining logic for the address sanitizer">;
def fsanitize_hwaddress_experimental_aliasing
: Flag<["-"], "fsanitize-hwaddress-experimental-aliasing">,
Group<f_clang_Group>,
diff --git a/clang/include/clang/Driver/SanitizerArgs.h b/clang/include/clang/Driver/SanitizerArgs.h
index 63a195fdf7537..e9e329e7cb53f 100644
--- a/clang/include/clang/Driver/SanitizerArgs.h
+++ b/clang/include/clang/Driver/SanitizerArgs.h
@@ -44,6 +44,7 @@ class SanitizerArgs {
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
index 68975aafcd370..8770fb1cf9fef 100644
--- a/clang/lib/Driver/SanitizerArgs.cpp
+++ b/clang/lib/Driver/SanitizerArgs.cpp
@@ -805,6 +805,11 @@ SanitizerArgs::SanitizerArgs(const ToolChain &TC,
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 @@ void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
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
index 0000000000000..280b51701e075
--- /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
index baa37b5fd79d9..b7d61abe7ec53 100644
--- 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
More information about the cfe-commits
mailing list