[llvm] [HLSL] Analyze updateCounter usage (PR #135669)

[Ashley Coleman via llvm-commits]

================
@@ -775,6 +778,42 @@ void DXILResourceMap::populate(Module &M, DXILResourceTypeMap &DRTM) {
     // Adjust the resource binding to use the next ID.
     RI.setBindingID(NextID++);
   }
+
+  for (Function &F : M.functions()) {
+    if (!isUpdateCounterIntrinsic(F))
+      continue;
+
+    LLVM_DEBUG(dbgs() << "Update Counter Function: " << F.getName() << "\n");
+
+    for (const User *U : F.users()) {
+      const CallInst *CI = dyn_cast<CallInst>(U);
+      assert(CI && "Users of dx_resource_updateCounter must be call instrs");
+
+      // Determine if the use is an increment or decrement
+      Value *CountArg = CI->getArgOperand(1);
+      ConstantInt *CountValue = cast<ConstantInt>(CountArg);
+      int64_t CountLiteral = CountValue->getSExtValue();
+
+      // 0 is an unknown direction and shouldn't result in an insert
+      if (CountLiteral == 0)
+        continue;
+
+      ResourceCounterDirection Direction = ResourceCounterDirection::Decrement;
+      if (CountLiteral > 0)
+        Direction = ResourceCounterDirection::Increment;
+
+      // Collect all potential creation points for the handle arg
+      Value *HandleArg = CI->getArgOperand(0);
+      SmallVector<ResourceInfo *> RBInfos = findByUse(HandleArg);
+      for (ResourceInfo *RBInfo : RBInfos) {
+        if (RBInfo->CounterDirection == ResourceCounterDirection::Unknown ||
+            RBInfo->CounterDirection == Direction)
+          RBInfo->CounterDirection = Direction;
+        else
+          RBInfo->CounterDirection = ResourceCounterDirection::Invalid;
----------------
V-FEXrt wrote:

Conflicting information! 

If CounterDirection is detected as both Increment and Decrement that is considered invalid (because only one direction is allowed)

https://github.com/llvm/llvm-project/pull/135669