diff --git a/docs/UndefinedBehaviorSanitizer.rst b/docs/UndefinedBehaviorSanitizer.rst
index db1325cc022e2b7e9be21687fc316cf5db81cd9a..7babb96a65a14c8330e4c64477f9d466433f17f2 100644
--- a/docs/UndefinedBehaviorSanitizer.rst
+++ b/docs/UndefinedBehaviorSanitizer.rst
@@ -228,6 +228,26 @@ UndefinedBehaviorSanitizer is available on selected platforms starting from LLVM
3.3. The test suite is integrated into the CMake build and can be run with
``check-ubsan`` command.
+Additional Configuration
+========================
+
+UndefinedBehaviorSanitizer adds static check data for each check unless it is
+in trap mode. This check data includes the full file name. The option
+``-fsanitize-undefined-strip-path-components=N`` can be used to trim this
+information. If ``N`` is positive, file information emitted by
+UndefinedBehaviorSanitizer will drop the first ``N`` components from the file
+path. If ``N`` is negative, the last ``N`` components will be kept.
+
+Example
+-------
+
+For a file called ``/code/library/file.cpp``, here is what would be emitted:
+* Default (No flag, or ``-fsanitize-undefined-strip-path-components=0``): ``/code/library/file.cpp``
+* ``-fsanitize-undefined-strip-path-components=1``: ``code/library/file.cpp``
+* ``-fsanitize-undefined-strip-path-components=2``: ``library/file.cpp``
+* ``-fsanitize-undefined-strip-path-components=-1``: ``file.cpp``
+* ``-fsanitize-undefined-strip-path-components=-2``: ``library/file.cpp``
+
More Information
================
diff --git a/include/clang/Driver/Options.td b/include/clang/Driver/Options.td
index 602e8fa7de7d00826a5c1ee66b089aba8dd3df3f..4dd092599a589d7edec244920189809ae37795a9 100644
--- a/include/clang/Driver/Options.td
+++ b/include/clang/Driver/Options.td
@@ -677,6 +677,10 @@ def fsanitize_stats : Flag<["-"], "fsanitize-stats">,
def fno_sanitize_stats : Flag<["-"], "fno-sanitize-stats">,
Group<f_clang_Group>, Flags<[CC1Option]>,
HelpText<"Disable sanitizer statistics gathering.">;
+def fsanitize_undefined_strip_path_components_EQ : Joined<["-"], "fsanitize-undefined-strip-path-components=">,
+ Group<f_clang_Group>, Flags<[CC1Option]>, MetaVarName<"<number>">,
+ HelpText<"Strip (or keep only, if negative) a given number of path components "
+ "when emitting check metadata.">;
def funsafe_math_optimizations : Flag<["-"], "funsafe-math-optimizations">,
Group<f_Group>;
def fno_unsafe_math_optimizations : Flag<["-"], "fno-unsafe-math-optimizations">,
diff --git a/include/clang/Frontend/CodeGenOptions.def b/include/clang/Frontend/CodeGenOptions.def
index d0d4f7a69399922184de2caed83dd4768ee96383..2e2344a8e4a487eca22401edc69fff8773ac4f47 100644
--- a/include/clang/Frontend/CodeGenOptions.def
+++ b/include/clang/Frontend/CodeGenOptions.def
@@ -225,6 +225,10 @@ ENUM_CODEGENOPT(VecLib, VectorLibrary, 1, NoLibrary)
/// The default TLS model to use.
ENUM_CODEGENOPT(DefaultTLSModel, TLSModel, 2, GeneralDynamicTLSModel)
+/// Number of path components to strip when emitting checks. (0 == full
+/// filename)
+VALUE_CODEGENOPT(EmitCheckPathComponentsToStrip, 32, 0)
+
#undef CODEGENOPT
#undef ENUM_CODEGENOPT
#undef VALUE_CODEGENOPT
diff --git a/lib/CodeGen/CGExpr.cpp b/lib/CodeGen/CGExpr.cpp
index 3ecd8e3f0f6c1d7437824400e67106e5ef39e8a1..8896eb4db123d09e79d0eef40cb83267e91f2940 100644
--- a/lib/CodeGen/CGExpr.cpp
+++ b/lib/CodeGen/CGExpr.cpp
@@ -32,6 +32,7 @@
#include "llvm/IR/MDBuilder.h"
#include "llvm/Support/ConvertUTF.h"
#include "llvm/Support/MathExtras.h"
+#include "llvm/Support/Path.h"
#include "llvm/Transforms/Utils/SanitizerStats.h"
using namespace clang;
@@ -2367,7 +2368,33 @@ llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) {
PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc);
if (PLoc.isValid()) {
- auto FilenameGV = CGM.GetAddrOfConstantCString(PLoc.getFilename(), ".src");
+ StringRef FilenameString = PLoc.getFilename();
+
+ int PathComponentsToStrip =
+ CGM.getCodeGenOpts().EmitCheckPathComponentsToStrip;
+ if (PathComponentsToStrip < 0) {
+ assert(PathComponentsToStrip != INT_MIN);
+ int PathComponentsToKeep = -PathComponentsToStrip;
+ auto I = llvm::sys::path::rbegin(FilenameString);
+ auto E = llvm::sys::path::rend(FilenameString);
+ while (I != E && --PathComponentsToKeep)
+ ++I;
+
+ FilenameString = FilenameString.substr(I - E);
+ } else if (PathComponentsToStrip > 0) {
+ auto I = llvm::sys::path::begin(FilenameString);
+ auto E = llvm::sys::path::end(FilenameString);
+ while (I != E && PathComponentsToStrip--)
+ ++I;
+
+ if (I != E)
+ FilenameString =
+ FilenameString.substr(I - llvm::sys::path::begin(FilenameString));
+ else
+ FilenameString = llvm::sys::path::filename(FilenameString);
+ }
+
+ auto FilenameGV = CGM.GetAddrOfConstantCString(FilenameString, ".src");
CGM.getSanitizerMetadata()->disableSanitizerForGlobal(
cast<llvm::GlobalVariable>(FilenameGV.getPointer()));
Filename = FilenameGV.getPointer();
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 98c0d1deebcdc464f4f935eb699479f793b25099..5da1fd6c969c7d9b80a851f8a9f79f12853c66a5 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -5607,6 +5607,10 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
if (Arg *A = Args.getLastArg(options::OPT_fshow_overloads_EQ))
A->render(Args, CmdArgs);
+ if (Arg *A = Args.getLastArg(
+ options::OPT_fsanitize_undefined_strip_path_components_EQ))
+ A->render(Args, CmdArgs);
+
// -fdollars-in-identifiers default varies depending on platform and
// language; only pass if specified.
if (Arg *A = Args.getLastArg(options::OPT_fdollars_in_identifiers,
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index f11188d0ff95af8d306a82d8e1f38f42400e0ea2..8e93ff1a4b4ef415ac856814ec21834f33fb67dc 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -823,6 +823,9 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
Opts.Backchain = Args.hasArg(OPT_mbackchain);
+ Opts.EmitCheckPathComponentsToStrip = getLastArgIntValue(
+ Args, OPT_fsanitize_undefined_strip_path_components_EQ, 0, Diags);
+
return Success;
}
diff --git a/test/CodeGen/ubsan-strip-path-components.cpp b/test/CodeGen/ubsan-strip-path-components.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..7a95324d128befba07d380335a3d69c3f0884841
--- /dev/null
+++ b/test/CodeGen/ubsan-strip-path-components.cpp
@@ -0,0 +1,29 @@
+// RUN: %clang_cc1 %s -triple=x86_64-linux-gnu -emit-llvm -fsanitize=unreachable -o - | FileCheck %s -check-prefix=REGULAR -check-prefix=CHECK
+// RUN: %clang_cc1 %s -triple=x86_64-linux-gnu -emit-llvm -fsanitize=unreachable -o - -fsanitize-undefined-strip-path-components=0 | FileCheck %s -check-prefix=REGULAR -check-prefix=CHECK
+// RUN: %clang_cc1 %s -triple=x86_64-linux-gnu -emit-llvm -fsanitize=unreachable -o - -fsanitize-undefined-strip-path-components=2 | FileCheck %s -check-prefix=REMOVE-FIRST-TWO -check-prefix=CHECK
+
+// Try to strip too much:
+// RUN: %clang_cc1 %s -triple=x86_64-linux-gnu -emit-llvm -fsanitize=unreachable -o - -fsanitize-undefined-strip-path-components=-99999 | FileCheck %s -check-prefix=REGULAR
+// RUN: %clang_cc1 %s -triple=x86_64-linux-gnu -emit-llvm -fsanitize=unreachable -o - -fsanitize-undefined-strip-path-components=99999 | FileCheck %s -check-prefix=LAST-ONLY
+
+// Check stripping from the file name
+// RUN: %clang_cc1 %s -triple=x86_64-linux-gnu -emit-llvm -fsanitize=unreachable -o - -fsanitize-undefined-strip-path-components=-2 | FileCheck %s -check-prefix=LAST-TWO
+// RUN: %clang_cc1 %s -triple=x86_64-linux-gnu -emit-llvm -fsanitize=unreachable -o - -fsanitize-undefined-strip-path-components=-1 | FileCheck %s -check-prefix=LAST-ONLY
+
+// REGULAR: @[[SRC:[0-9.a-zA-Z_]+]] = private unnamed_addr constant [{{.*}} x i8] c"{{.*test(.|\\5C)CodeGen(.|\\5C)ubsan-strip-path-components\.cpp}}\00", align 1
+
+// First path component: "/" or "$drive_letter:", then a name, or '\5C' on Windows
+// REMOVE-FIRST-TWO: @[[STR:[0-9.a-zA-Z_]+]] = private unnamed_addr constant [{{.*}} x i8] c"{{(.:|/)([^\\/]*(/|\\5C))}}[[REST:.*ubsan-strip-path-components\.cpp]]\00", align 1
+// REMOVE-FIRST-TWO: @[[SRC:[0-9.a-zA-Z_]+]] = private unnamed_addr constant [{{.*}} x i8] c"[[REST]]\00", align 1
+
+// LAST-TWO: @[[SRC:[0-9.a-zA-Z_]+]] = private unnamed_addr constant [{{.*}} x i8] c"CodeGen{{/|\\5C}}ubsan-strip-path-components.cpp\00", align 1
+// LAST-ONLY: @[[SRC:[0-9.a-zA-Z_]+]] = private unnamed_addr constant [{{.*}} x i8] c"ubsan-strip-path-components.cpp\00", align 1
+
+// CHECK: @[[STATIC_DATA:[0-9.a-zA-Z_]+]] = private unnamed_addr global { { [{{.*}} x i8]*, i32, i32 } } { { [{{.*}} x i8]*, i32, i32 } { [{{.*}} x i8]* @[[SRC]], i32 [[@LINE+6]], i32 3 } }
+void g(const char *);
+void f() {
+ // CHECK-LABEL: @_Z1fv(
+ g(__FILE__);
+ // CHECK: call void @__ubsan_handle_builtin_unreachable(i8* bitcast ({ { [{{.*}} x i8]*, i32, i32 } }* @[[STATIC_DATA]] to i8*)) {{.*}}, !nosanitize
+ __builtin_unreachable();
+}
diff --git a/test/Driver/fubsan-strip-path-components.cpp b/test/Driver/fubsan-strip-path-components.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..130024142f20d15d2f6c9735015025a3d41891d2
--- /dev/null
+++ b/test/Driver/fubsan-strip-path-components.cpp
@@ -0,0 +1,2 @@
+// RUN: %clang %s -### -o %t.o -fsanitize-undefined-strip-path-components=42 2>&1 | FileCheck %s
+// CHECK: "-fsanitize-undefined-strip-path-components=42"