1 files changed, 14 insertions, 12 deletions

diff --git a/clang/lib/CodeGen/CGStmt.cpp b/clang/lib/CodeGen/CGStmt.cpp
index 92636f2..fdc1a11 100644
--- a/clang/lib/CodeGen/CGStmt.cpp
+++ b/clang/lib/CodeGen/CGStmt.cpp
@@ -2674,7 +2674,8 @@ EmitAsmStores(CodeGenFunction &CGF, const AsmStmt &S,
               const llvm::ArrayRef<LValue> ResultRegDests,
               const llvm::ArrayRef<QualType> ResultRegQualTys,
               const llvm::BitVector &ResultTypeRequiresCast,
-              const llvm::BitVector &ResultRegIsFlagReg) {
+              const std::vector<std::optional<std::pair<unsigned, unsigned>>>
+                  &ResultBounds) {
   CGBuilderTy &Builder = CGF.Builder;
   CodeGenModule &CGM = CGF.CGM;
   llvm::LLVMContext &CTX = CGF.getLLVMContext();
@@ -2685,18 +2686,20 @@ EmitAsmStores(CodeGenFunction &CGF, const AsmStmt &S,
   // ResultRegDests can be also populated by addReturnRegisterOutputs() above,
   // in which case its size may grow.
   assert(ResultTypeRequiresCast.size() <= ResultRegDests.size());
-  assert(ResultRegIsFlagReg.size() <= ResultRegDests.size());
+  assert(ResultBounds.size() <= ResultRegDests.size());
 
   for (unsigned i = 0, e = RegResults.size(); i != e; ++i) {
     llvm::Value *Tmp = RegResults[i];
     llvm::Type *TruncTy = ResultTruncRegTypes[i];
 
-    if ((i < ResultRegIsFlagReg.size()) && ResultRegIsFlagReg[i]) {
-      // Target must guarantee the Value `Tmp` here is lowered to a boolean
-      // value.
-      llvm::Constant *Two = llvm::ConstantInt::get(Tmp->getType(), 2);
+    if ((i < ResultBounds.size()) && ResultBounds[i].has_value()) {
+      const auto [LowerBound, UpperBound] = ResultBounds[i].value();
+      // FIXME: Support for nonzero lower bounds not yet implemented.
+      assert(LowerBound == 0 && "Output operand lower bound is not zero.");
+      llvm::Constant *UpperBoundConst =
+          llvm::ConstantInt::get(Tmp->getType(), UpperBound);
       llvm::Value *IsBooleanValue =
-          Builder.CreateCmp(llvm::CmpInst::ICMP_ULT, Tmp, Two);
+          Builder.CreateCmp(llvm::CmpInst::ICMP_ULT, Tmp, UpperBoundConst);
       llvm::Function *FnAssume = CGM.getIntrinsic(llvm::Intrinsic::assume);
       Builder.CreateCall(FnAssume, IsBooleanValue);
     }
@@ -2825,7 +2828,7 @@ void CodeGenFunction::EmitAsmStmt(const AsmStmt &S) {
   std::vector<llvm::Type *> ArgElemTypes;
   std::vector<llvm::Value*> Args;
   llvm::BitVector ResultTypeRequiresCast;
-  llvm::BitVector ResultRegIsFlagReg;
+  std::vector<std::optional<std::pair<unsigned, unsigned>>> ResultBounds;
 
   // Keep track of inout constraints.
   std::string InOutConstraints;
@@ -2883,8 +2886,7 @@ void CodeGenFunction::EmitAsmStmt(const AsmStmt &S) {
       ResultRegQualTys.push_back(QTy);
       ResultRegDests.push_back(Dest);
 
-      bool IsFlagReg = llvm::StringRef(OutputConstraint).starts_with("{@cc");
-      ResultRegIsFlagReg.push_back(IsFlagReg);
+      ResultBounds.emplace_back(Info.getOutputOperandBounds());
 
       llvm::Type *Ty = ConvertTypeForMem(QTy);
       const bool RequiresCast = Info.allowsRegister() &&
@@ -3231,7 +3233,7 @@ void CodeGenFunction::EmitAsmStmt(const AsmStmt &S) {
 
   EmitAsmStores(*this, S, RegResults, ResultRegTypes, ResultTruncRegTypes,
                 ResultRegDests, ResultRegQualTys, ResultTypeRequiresCast,
-                ResultRegIsFlagReg);
+                ResultBounds);
 
   // If this is an asm goto with outputs, repeat EmitAsmStores, but with a
   // different insertion point; one for each indirect destination and with
@@ -3242,7 +3244,7 @@ void CodeGenFunction::EmitAsmStmt(const AsmStmt &S) {
       Builder.SetInsertPoint(Succ, --(Succ->end()));
       EmitAsmStores(*this, S, CBRRegResults[Succ], ResultRegTypes,
                     ResultTruncRegTypes, ResultRegDests, ResultRegQualTys,
-                    ResultTypeRequiresCast, ResultRegIsFlagReg);
+                    ResultTypeRequiresCast, ResultBounds);
     }
   }
 }