10 files changed, 19 insertions, 3 deletions

diff --git a/llvm/lib/AsmParser/LLLexer.cpp b/llvm/lib/AsmParser/LLLexer.cpp
index b543115a88e..a60639bef0c 100644
--- a/llvm/lib/AsmParser/LLLexer.cpp
+++ b/llvm/lib/AsmParser/LLLexer.cpp
@@ -656,6 +656,7 @@ lltok::Kind LLLexer::LexIdentifier() {
   KEYWORD(nonnull);
   KEYWORD(noredzone);
   KEYWORD(noreturn);
+  KEYWORD(expect_noreturn);
   KEYWORD(nocf_check);
   KEYWORD(nounwind);
   KEYWORD(optforfuzzing);
diff --git a/llvm/lib/AsmParser/LLParser.cpp b/llvm/lib/AsmParser/LLParser.cpp
index 855c5d26500..9167694607f 100644
--- a/llvm/lib/AsmParser/LLParser.cpp
+++ b/llvm/lib/AsmParser/LLParser.cpp
@@ -1248,6 +1248,8 @@ bool LLParser::ParseFnAttributeValuePairs(AttrBuilder &B,
     case lltok::kw_nonlazybind: B.addAttribute(Attribute::NonLazyBind); break;
     case lltok::kw_noredzone: B.addAttribute(Attribute::NoRedZone); break;
     case lltok::kw_noreturn: B.addAttribute(Attribute::NoReturn); break;
+    case lltok::kw_expect_noreturn:
+      B.addAttribute(Attribute::ExpectNoReturn); break;
     case lltok::kw_nocf_check: B.addAttribute(Attribute::NoCfCheck); break;
     case lltok::kw_norecurse: B.addAttribute(Attribute::NoRecurse); break;
     case lltok::kw_nounwind: B.addAttribute(Attribute::NoUnwind); break;
@@ -1611,6 +1613,7 @@ bool LLParser::ParseOptionalParamAttrs(AttrBuilder &B) {
     case lltok::kw_nonlazybind:
     case lltok::kw_noredzone:
     case lltok::kw_noreturn:
+    case lltok::kw_expect_noreturn:
     case lltok::kw_nocf_check:
     case lltok::kw_nounwind:
     case lltok::kw_optforfuzzing:
@@ -1708,6 +1711,7 @@ bool LLParser::ParseOptionalReturnAttrs(AttrBuilder &B) {
     case lltok::kw_nonlazybind:
     case lltok::kw_noredzone:
     case lltok::kw_noreturn:
+    case lltok::kw_expect_noreturn:
     case lltok::kw_nocf_check:
     case lltok::kw_nounwind:
     case lltok::kw_optforfuzzing:
diff --git a/llvm/lib/AsmParser/LLToken.h b/llvm/lib/AsmParser/LLToken.h
index 41899b29ce5..b90394f4c1f 100644
--- a/llvm/lib/AsmParser/LLToken.h
+++ b/llvm/lib/AsmParser/LLToken.h
@@ -200,6 +200,7 @@ enum Kind {
   kw_nonnull,
   kw_noredzone,
   kw_noreturn,
+  kw_expect_noreturn,
   kw_nocf_check,
   kw_nounwind,
   kw_optforfuzzing,
diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index 0b93a61dc40..d377b6ae515 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -1186,8 +1186,8 @@ static uint64_t getRawAttributeMask(Attribute::AttrKind Val) {
   case Attribute::NoCfCheck:       return 1ULL << 57;
   case Attribute::OptForFuzzing:   return 1ULL << 58;
   case Attribute::ShadowCallStack: return 1ULL << 59;
-  case Attribute::SpeculativeLoadHardening:
-    return 1ULL << 60;
+  case Attribute::SpeculativeLoadHardening: return 1ULL << 60;
+  case Attribute::ExpectNoReturn:  return 1ULL << 61;
   case Attribute::Dereferenceable:
     llvm_unreachable("dereferenceable attribute not supported in raw format");
     break;
@@ -1366,6 +1366,8 @@ static Attribute::AttrKind getAttrFromCode(uint64_t Code) {
     return Attribute::NoRedZone;
   case bitc::ATTR_KIND_NO_RETURN:
     return Attribute::NoReturn;
+  case bitc::ATTR_KIND_EXPECT_NO_RETURN:
+    return Attribute::ExpectNoReturn;
   case bitc::ATTR_KIND_NOCF_CHECK:
     return Attribute::NoCfCheck;
   case bitc::ATTR_KIND_NO_UNWIND:
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index f4a539e51f7..f16cdacaae3 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -654,6 +654,8 @@ static uint64_t getAttrKindEncoding(Attribute::AttrKind Kind) {
     return bitc::ATTR_KIND_NO_RED_ZONE;
   case Attribute::NoReturn:
     return bitc::ATTR_KIND_NO_RETURN;
+  case Attribute::ExpectNoReturn:
+    return bitc::ATTR_KIND_EXPECT_NO_RETURN;
   case Attribute::NoCfCheck:
     return bitc::ATTR_KIND_NOCF_CHECK;
   case Attribute::NoUnwind:
diff --git a/llvm/lib/IR/Attributes.cpp b/llvm/lib/IR/Attributes.cpp
index a474d5740fe..ab49adba81c 100644
--- a/llvm/lib/IR/Attributes.cpp
+++ b/llvm/lib/IR/Attributes.cpp
@@ -298,6 +298,8 @@ std::string Attribute::getAsString(bool InAttrGrp) const {
     return "noredzone";
   if (hasAttribute(Attribute::NoReturn))
     return "noreturn";
+  if (hasAttribute(Attribute::ExpectNoReturn))
+    return "expect_noreturn";
   if (hasAttribute(Attribute::NoCfCheck))
     return "nocf_check";
   if (hasAttribute(Attribute::NoRecurse))
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 1000e210533..3b3e3158059 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -1477,6 +1477,7 @@ void Verifier::visitModuleFlagCGProfileEntry(const MDOperand &MDO) {
 static bool isFuncOnlyAttr(Attribute::AttrKind Kind) {
   switch (Kind) {
   case Attribute::NoReturn:
+  case Attribute::ExpectNoReturn:
   case Attribute::NoCfCheck:
   case Attribute::NoUnwind:
   case Attribute::NoInline:
diff --git a/llvm/lib/Transforms/IPO/ForceFunctionAttrs.cpp b/llvm/lib/Transforms/IPO/ForceFunctionAttrs.cpp
index cd1fc379820..7300ca06ce7 100644
--- a/llvm/lib/Transforms/IPO/ForceFunctionAttrs.cpp
+++ b/llvm/lib/Transforms/IPO/ForceFunctionAttrs.cpp
@@ -41,6 +41,7 @@ static Attribute::AttrKind parseAttrKind(StringRef Kind) {
       .Case("nonlazybind", Attribute::NonLazyBind)
       .Case("noredzone", Attribute::NoRedZone)
       .Case("noreturn", Attribute::NoReturn)
+      .Case("expect_noreturn", Attribute::ExpectNoReturn)
       .Case("nocf_check", Attribute::NoCfCheck)
       .Case("norecurse", Attribute::NoRecurse)
       .Case("nounwind", Attribute::NoUnwind)
diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 1a007b4258f..8d27ee9d1e1 100644
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -2568,7 +2568,8 @@ bool AddressSanitizer::runOnFunction(Function &F) {
         if (CS) {
           // A call inside BB.
           TempsToInstrument.clear();
-          if (CS.doesNotReturn()) NoReturnCalls.push_back(CS.getInstruction());
+          if (CS.doesNotReturn() || CS.hasFnAttr(Attribute::ExpectNoReturn))
+            NoReturnCalls.push_back(CS.getInstruction());
         }
         if (CallInst *CI = dyn_cast<CallInst>(&Inst))
           maybeMarkSanitizerLibraryCallNoBuiltin(CI, TLI);
diff --git a/llvm/lib/Transforms/Utils/CodeExtractor.cpp b/llvm/lib/Transforms/Utils/CodeExtractor.cpp
index 03e2b9db078..3cf26b5e0c3 100644
--- a/llvm/lib/Transforms/Utils/CodeExtractor.cpp
+++ b/llvm/lib/Transforms/Utils/CodeExtractor.cpp
@@ -779,6 +779,7 @@ Function *CodeExtractor::constructFunction(const ValueSet &inputs,
       case Attribute::NoBuiltin:
       case Attribute::NoCapture:
       case Attribute::NoReturn:
+      case Attribute::ExpectNoReturn:
       case Attribute::None:
       case Attribute::NonNull:
       case Attribute::ReadNone: