vendor/llvm-project/llvmorg-16-init-18548-gb0daacf58f41

1 files changed, 37 insertions, 20 deletions

diff --git a/llvm/lib/Transforms/Utils/LowerAtomic.cpp b/llvm/lib/Transforms/Utils/LowerAtomic.cpp
index 2247b8107739..b6f40de0daa6 100644
--- a/llvm/lib/Transforms/Utils/LowerAtomic.cpp
+++ b/llvm/lib/Transforms/Utils/LowerAtomic.cpp
@@ -41,43 +41,60 @@ bool llvm::lowerAtomicCmpXchgInst(AtomicCmpXchgInst *CXI) {
 
 Value *llvm::buildAtomicRMWValue(AtomicRMWInst::BinOp Op,
                                  IRBuilderBase &Builder, Value *Loaded,
-                                 Value *Inc) {
+                                 Value *Val) {
   Value *NewVal;
   switch (Op) {
   case AtomicRMWInst::Xchg:
-    return Inc;
+    return Val;
   case AtomicRMWInst::Add:
-    return Builder.CreateAdd(Loaded, Inc, "new");
+    return Builder.CreateAdd(Loaded, Val, "new");
   case AtomicRMWInst::Sub:
-    return Builder.CreateSub(Loaded, Inc, "new");
+    return Builder.CreateSub(Loaded, Val, "new");
   case AtomicRMWInst::And:
-    return Builder.CreateAnd(Loaded, Inc, "new");
+    return Builder.CreateAnd(Loaded, Val, "new");
   case AtomicRMWInst::Nand:
-    return Builder.CreateNot(Builder.CreateAnd(Loaded, Inc), "new");
+    return Builder.CreateNot(Builder.CreateAnd(Loaded, Val), "new");
   case AtomicRMWInst::Or:
-    return Builder.CreateOr(Loaded, Inc, "new");
+    return Builder.CreateOr(Loaded, Val, "new");
   case AtomicRMWInst::Xor:
-    return Builder.CreateXor(Loaded, Inc, "new");
+    return Builder.CreateXor(Loaded, Val, "new");
   case AtomicRMWInst::Max:
-    NewVal = Builder.CreateICmpSGT(Loaded, Inc);
-    return Builder.CreateSelect(NewVal, Loaded, Inc, "new");
+    NewVal = Builder.CreateICmpSGT(Loaded, Val);
+    return Builder.CreateSelect(NewVal, Loaded, Val, "new");
   case AtomicRMWInst::Min:
-    NewVal = Builder.CreateICmpSLE(Loaded, Inc);
-    return Builder.CreateSelect(NewVal, Loaded, Inc, "new");
+    NewVal = Builder.CreateICmpSLE(Loaded, Val);
+    return Builder.CreateSelect(NewVal, Loaded, Val, "new");
   case AtomicRMWInst::UMax:
-    NewVal = Builder.CreateICmpUGT(Loaded, Inc);
-    return Builder.CreateSelect(NewVal, Loaded, Inc, "new");
+    NewVal = Builder.CreateICmpUGT(Loaded, Val);
+    return Builder.CreateSelect(NewVal, Loaded, Val, "new");
   case AtomicRMWInst::UMin:
-    NewVal = Builder.CreateICmpULE(Loaded, Inc);
-    return Builder.CreateSelect(NewVal, Loaded, Inc, "new");
+    NewVal = Builder.CreateICmpULE(Loaded, Val);
+    return Builder.CreateSelect(NewVal, Loaded, Val, "new");
   case AtomicRMWInst::FAdd:
-    return Builder.CreateFAdd(Loaded, Inc, "new");
+    return Builder.CreateFAdd(Loaded, Val, "new");
   case AtomicRMWInst::FSub:
-    return Builder.CreateFSub(Loaded, Inc, "new");
+    return Builder.CreateFSub(Loaded, Val, "new");
   case AtomicRMWInst::FMax:
-    return Builder.CreateMaxNum(Loaded, Inc);
+    return Builder.CreateMaxNum(Loaded, Val);
   case AtomicRMWInst::FMin:
-    return Builder.CreateMinNum(Loaded, Inc);
+    return Builder.CreateMinNum(Loaded, Val);
+  case AtomicRMWInst::UIncWrap: {
+    Constant *One = ConstantInt::get(Loaded->getType(), 1);
+    Value *Inc = Builder.CreateAdd(Loaded, One);
+    Value *Cmp = Builder.CreateICmpUGE(Loaded, Val);
+    Constant *Zero = ConstantInt::get(Loaded->getType(), 0);
+    return Builder.CreateSelect(Cmp, Zero, Inc, "new");
+  }
+  case AtomicRMWInst::UDecWrap: {
+    Constant *Zero = ConstantInt::get(Loaded->getType(), 0);
+    Constant *One = ConstantInt::get(Loaded->getType(), 1);
+
+    Value *Dec = Builder.CreateSub(Loaded, One);
+    Value *CmpEq0 = Builder.CreateICmpEQ(Loaded, Zero);
+    Value *CmpOldGtVal = Builder.CreateICmpUGT(Loaded, Val);
+    Value *Or = Builder.CreateOr(CmpEq0, CmpOldGtVal);
+    return Builder.CreateSelect(Or, Val, Dec, "new");
+  }
   default:
     llvm_unreachable("Unknown atomic op");
   }