[sancov] Disable sanitizer coverage on functions using SEH

Splitting basic blocks really messes up WinEHPrepare. We can remove this
change when SEH uses the new EH IR.

llvm-svn: 246799

2 files changed, 11 insertions, 6 deletions

diff --git a/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp b/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp
index 3bcb8de1c4f..b021f31e652 100644
--- a/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp
+++ b/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp
@@ -31,6 +31,7 @@
 #include "llvm/Transforms/Instrumentation.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/SmallVector.h"
+#include "llvm/Analysis/LibCallSemantics.h"
 #include "llvm/IR/CallSite.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/DebugInfo.h"
@@ -290,6 +291,12 @@ bool SanitizerCoverageModule::runOnFunction(Function &F) {
   if (F.empty()) return false;
   if (F.getName().find(".module_ctor") != std::string::npos)
     return false;  // Should not instrument sanitizer init functions.
+  // Don't instrument functions using SEH for now. Splitting basic blocks like
+  // we do for coverage breaks WinEHPrepare.
+  // FIXME: Remove this when SEH no longer uses landingpad pattern matching.
+  if (F.hasPersonalityFn() &&
+      isAsynchronousEHPersonality(classifyEHPersonality(F.getPersonalityFn())))
+    return false;
   if (Options.CoverageType >= SanitizerCoverageOptions::SCK_Edge)
     SplitAllCriticalEdges(F);
   SmallVector<Instruction*, 8> IndirCalls;
diff --git a/llvm/test/Instrumentation/SanitizerCoverage/localescape.ll b/llvm/test/Instrumentation/SanitizerCoverage/seh.ll
index eff47c64f09..ce18334ed20 100644
--- a/llvm/test/Instrumentation/SanitizerCoverage/localescape.ll
+++ b/llvm/test/Instrumentation/SanitizerCoverage/seh.ll
@@ -45,14 +45,12 @@ eh.resume:                                        ; preds = %lpad
   resume { i8*, i32 } %1
 }
 
-; Check that the alloca remains static and the localescape call remains in the
-; entry block.
+; Check that we don't do any instrumentation.
 
 ; CHECK-LABEL: define i32 @main()
-; CHECK-NOT: br {{.*}}label
-; CHECK: %__exception_code = alloca i32, align 4
-; CHECK-NOT: br {{.*}}label
-; CHECK: call void (...) @llvm.localescape(i32* nonnull %__exception_code)
+; CHECK-NOT: load atomic i32, i32* {{.*}} monotonic, align 4, !nosanitize
+; CHECK-NOT: call void @__sanitizer_cov
+; CHECK: ret i32
 
 ; Function Attrs: nounwind
 define internal i32 @"\01?filt$0@0@main@@"() #1 {