[clang] 4fbc66c - [Clang] Enable __has_feature(coverage_sanitizer)

[Marco Elver via cfe-commits]

Author: Marco Elver
Date: 2021-05-27T18:24:21+02:00
New Revision: 4fbc66cd6d90d8d5169c43fcc1b1e26e8a98d3a9

URL: https://github.com/llvm/llvm-project/commit/4fbc66cd6d90d8d5169c43fcc1b1e26e8a98d3a9
DIFF: https://github.com/llvm/llvm-project/commit/4fbc66cd6d90d8d5169c43fcc1b1e26e8a98d3a9.diff

LOG: [Clang] Enable __has_feature(coverage_sanitizer)

Like other sanitizers, enable __has_feature(coverage_sanitizer) if clang
has enabled at least one SanitizerCoverage instrumentation type.

Because coverage instrumentation selection is not handled via normal
-fsanitize= (and thus not in SanitizeSet), passing this information
through to LangOptions required propagating the already parsed
-fsanitize-coverage= options from CodeGenOptions through to LangOptions
in FixupInvocation().

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D103159

Added: 
    clang/test/Lexer/has_feature_coverage_sanitizer.cpp

Modified: 
    clang/docs/SanitizerCoverage.rst
    clang/include/clang/Basic/Features.def
    clang/include/clang/Basic/LangOptions.h
    clang/lib/Frontend/CompilerInvocation.cpp

Removed: 
    


################################################################################
diff  --git a/clang/docs/SanitizerCoverage.rst b/clang/docs/SanitizerCoverage.rst
index b0bb9823eb043..ebd5d72127aaa 100644
--- a/clang/docs/SanitizerCoverage.rst
+++ b/clang/docs/SanitizerCoverage.rst
@@ -316,7 +316,9 @@ Disabling instrumentation with ``__attribute__((no_sanitize("coverage")))``
 ===========================================================================
 
 It is possible to disable coverage instrumentation for select functions via the
-function attribute ``__attribute__((no_sanitize("coverage")))``.
+function attribute ``__attribute__((no_sanitize("coverage")))``. Because this
+attribute may not be supported by other compilers, it is recommended to use it
+together with ``__has_feature(coverage_sanitizer)``.
 
 Disabling instrumentation without source modification
 =====================================================

diff  --git a/clang/include/clang/Basic/Features.def b/clang/include/clang/Basic/Features.def
index 4f7e2db7683d0..a7a5e06a937e0 100644
--- a/clang/include/clang/Basic/Features.def
+++ b/clang/include/clang/Basic/Features.def
@@ -49,6 +49,7 @@ FEATURE(memtag_sanitizer, LangOpts.Sanitize.has(SanitizerKind::MemTag))
 FEATURE(xray_instrument, LangOpts.XRayInstrument)
 FEATURE(undefined_behavior_sanitizer,
         LangOpts.Sanitize.hasOneOf(SanitizerKind::Undefined))
+FEATURE(coverage_sanitizer, LangOpts.SanitizeCoverage)
 FEATURE(assume_nonnull, true)
 FEATURE(attribute_analyzer_noreturn, true)
 FEATURE(attribute_availability, true)

diff  --git a/clang/include/clang/Basic/LangOptions.h b/clang/include/clang/Basic/LangOptions.h
index f5975d89a299e..d618daf3d23c2 100644
--- a/clang/include/clang/Basic/LangOptions.h
+++ b/clang/include/clang/Basic/LangOptions.h
@@ -280,6 +280,8 @@ class LangOptions : public LangOptionsBase {
 
   /// Set of enabled sanitizers.
   SanitizerSet Sanitize;
+  /// Is at least one coverage instrumentation type enabled.
+  bool SanitizeCoverage = false;
 
   /// Paths to files specifying which objects
   /// (files, functions, variables) should not be instrumented.

diff  --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 809492a36d3fa..28cd8391e32e2 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -453,7 +453,7 @@ static bool FixupInvocation(CompilerInvocation &Invocation,
   CodeGenOpts.XRayAlwaysEmitTypedEvents = LangOpts.XRayAlwaysEmitTypedEvents;
   CodeGenOpts.DisableFree = FrontendOpts.DisableFree;
   FrontendOpts.GenerateGlobalModuleIndex = FrontendOpts.UseGlobalModuleIndex;
-
+  LangOpts.SanitizeCoverage = CodeGenOpts.hasSanitizeCoverage();
   LangOpts.ForceEmitVTables = CodeGenOpts.ForceEmitVTables;
   LangOpts.SpeculativeLoadHardening = CodeGenOpts.SpeculativeLoadHardening;
   LangOpts.CurrentModule = LangOpts.ModuleName;

diff  --git a/clang/test/Lexer/has_feature_coverage_sanitizer.cpp b/clang/test/Lexer/has_feature_coverage_sanitizer.cpp
new file mode 100644
index 0000000000000..dfbe3973be043
--- /dev/null
+++ b/clang/test/Lexer/has_feature_coverage_sanitizer.cpp
@@ -0,0 +1,15 @@
+// RUN: %clang -E -fsanitize-coverage=indirect-calls %s -o - | FileCheck --check-prefix=CHECK-SANCOV %s
+// RUN: %clang -E -fsanitize-coverage=inline-8bit-counters %s -o - | FileCheck --check-prefix=CHECK-SANCOV %s
+// RUN: %clang -E -fsanitize-coverage=trace-cmp %s -o - | FileCheck --check-prefix=CHECK-SANCOV %s
+// RUN: %clang -E -fsanitize-coverage=trace-pc %s -o - | FileCheck --check-prefix=CHECK-SANCOV %s
+// RUN: %clang -E -fsanitize-coverage=trace-pc-guard %s -o - | FileCheck --check-prefix=CHECK-SANCOV %s
+// RUN: %clang -E  %s -o - | FileCheck --check-prefix=CHECK-NO-SANCOV %s
+
+#if __has_feature(coverage_sanitizer)
+int SancovEnabled();
+#else
+int SancovDisabled();
+#endif
+
+// CHECK-SANCOV: SancovEnabled
+// CHECK-NO-SANCOV: SancovDisabled