Add the 'noinline' attribute to call sites within __try bodies

LLVM doesn't support non-call exceptions, so inlining makes it harder to
catch such asynchronous exceptions.

llvm-svn: 228876

4 files changed, 16 insertions, 2 deletions

diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index 0574a1a34dc..60ab2effbeb 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -3325,6 +3325,12 @@ RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo,
         Attrs.addAttribute(getLLVMContext(), llvm::AttributeSet::FunctionIndex,
                            llvm::Attribute::AlwaysInline);
 
+  // Disable inlining inside SEH __try blocks.
+  if (IsSEHTryScope)
+    Attrs =
+        Attrs.addAttribute(getLLVMContext(), llvm::AttributeSet::FunctionIndex,
+                           llvm::Attribute::NoInline);
+
   CS.setAttributes(Attrs);
   CS.setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv));
 
diff --git a/clang/lib/CodeGen/CGException.cpp b/clang/lib/CodeGen/CGException.cpp
index 9df4f977318..b8ce205ff1b 100644
--- a/clang/lib/CodeGen/CGException.cpp
+++ b/clang/lib/CodeGen/CGException.cpp
@@ -21,6 +21,7 @@
 #include "clang/AST/StmtObjC.h"
 #include "llvm/IR/CallSite.h"
 #include "llvm/IR/Intrinsics.h"
+#include "llvm/Support/SaveAndRestore.h"
 
 using namespace clang;
 using namespace CodeGen;
@@ -1703,7 +1704,11 @@ void CodeGenFunction::EmitSEHTryStmt(const SEHTryStmt &S) {
 
   SEHFinallyInfo FI;
   EnterSEHTryStmt(S, FI);
-  EmitStmt(S.getTryBlock());
+  {
+    // Disable inlining inside SEH __try scopes.
+    SaveAndRestore<bool> Saver(IsSEHTryScope, true);
+    EmitStmt(S.getTryBlock());
+  }
   ExitSEHTryStmt(S, FI);
 }
 
diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index 79425d4c21e..43dd7a05de1 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -40,7 +40,7 @@ CodeGenFunction::CodeGenFunction(CodeGenModule &cgm, bool suppressNewContext)
       CurFn(nullptr), CapturedStmtInfo(nullptr),
       SanOpts(CGM.getLangOpts().Sanitize), IsSanitizerScope(false),
       CurFuncIsThunk(false), AutoreleaseResult(false), SawAsmBlock(false),
-      BlockInfo(nullptr), BlockPointer(nullptr),
+      IsSEHTryScope(false), BlockInfo(nullptr), BlockPointer(nullptr),
       LambdaThisCaptureField(nullptr), NormalCleanupDest(nullptr),
       NextCleanupDestIndex(1), FirstBlockInfo(nullptr), EHResumeBlock(nullptr),
       ExceptionSlot(nullptr), EHSelectorSlot(nullptr),
diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 998e0676cd2..6011333c9dd 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -263,6 +263,9 @@ public:
   /// potentially set the return value.
   bool SawAsmBlock;
 
+  /// Codegen is currently inside an SEH try block.
+  bool IsSEHTryScope;
+
   const CodeGen::CGBlockInfo *BlockInfo;
   llvm::Value *BlockPointer;