[llvm-branch-commits] [llvm] [DirectX] Lower `llvm.dx.resource.handlefromheap` intrinsic (PR #216459)

via llvm-branch-commits llvm-branch-commits at lists.llvm.org
Sun Aug 16 23:46:44 PDT 2026


llvmorg-github-actions[bot] wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-directx

Author: Helena Kotas (hekota)

<details>
<summary>Changes</summary>

Add lowering of `llvm.dx.resource.handlefromheap` intrinsic. It gets translated to DXIL ops `createHandleFromHeap` and `annotateHandle`.

For example, the intrinsic call

```llvm
%typed = call target("dx.TypedBuffer", <4 x float>, 1, 0, 0)
    @<!-- -->llvm.dx.resource.handlefromheap.tdx.TypedBuffer_v4f32_1_0_0(i32 3, i1 false)
```

will lower to

```llvm
%0 = call %dx.types.Handle @<!-- -->dx.op.createHandleFromHeap(i32 218, i32 3, i1 false, i1 false)
%1 = call %dx.types.Handle @<!-- -->dx.op.annotateHandle(i32 216, %dx.types.Handle %0,
         %dx.types.ResourceProperties { i32 4106, i32 1033 })
```

The value of non-uniform index flag is calculated using existing `hasNonUniformIndex` helper function.

Fixes #<!-- -->91406

Depends on #<!-- -->216454 

---
Full diff: https://github.com/llvm/llvm-project/pull/216459.diff


4 Files Affected:

- (modified) llvm/lib/Target/DirectX/DXIL.td (+8) 
- (modified) llvm/lib/Target/DirectX/DXILOpLowering.cpp (+45) 
- (added) llvm/test/CodeGen/DirectX/CreateHandleHeap-NURI.ll (+33) 
- (added) llvm/test/CodeGen/DirectX/CreateHandleHeap.ll (+32) 


``````````diff
diff --git a/llvm/lib/Target/DirectX/DXIL.td b/llvm/lib/Target/DirectX/DXIL.td
index bbf7cddb5c17c..4beafd0c619b0 100644
--- a/llvm/lib/Target/DirectX/DXIL.td
+++ b/llvm/lib/Target/DirectX/DXIL.td
@@ -1531,3 +1531,11 @@ def CreateHandleFromBinding : DXILOp<217, createHandleFromBinding> {
   let stages = [Stages<DXIL1_6, [all_stages]>];
   let attributes = [Attributes<DXIL1_0, [ReadNone]>];
 }
+
+def CreateHandleFromHeap : DXILOp<218, createHandleFromHeap> {
+  let Doc = "create resource handle from heap";
+  let arguments = [Int32Ty, Int1Ty, Int1Ty];
+  let result = HandleTy;
+  let stages = [Stages<DXIL1_6, [all_stages]>];
+  let attributes = [Attributes<DXIL1_0, [ReadNone]>];
+}
diff --git a/llvm/lib/Target/DirectX/DXILOpLowering.cpp b/llvm/lib/Target/DirectX/DXILOpLowering.cpp
index dc15c02481468..b0e58c6559c9d 100644
--- a/llvm/lib/Target/DirectX/DXILOpLowering.cpp
+++ b/llvm/lib/Target/DirectX/DXILOpLowering.cpp
@@ -433,6 +433,48 @@ class OpLowerer {
     return lowerToBindAndAnnotateHandle(F);
   }
 
+  bool lowerHandleFromHeap(Function &F) {
+    IRBuilder<> &IRB = OpBuilder.getIRB();
+    Type *Int1Ty = IRB.getInt1Ty();
+
+    return replaceFunction(F, [&](CallInst *CI) -> Error {
+      IRB.SetInsertPoint(CI);
+
+      auto *It = DRM.find(CI);
+      assert(It != DRM.end() && "Resource not in map?");
+      dxil::ResourceInfo &RI = *It;
+      dxil::ResourceTypeInfo &RTI = DRTM[RI.getHandleTy()];
+
+      Value *IndexOp = CI->getArgOperand(0);
+      Value *IsSamplerHeap = CI->getArgOperand(1);
+
+      std::pair<uint32_t, uint32_t> Props =
+          RI.getAnnotateProps(*F.getParent(), RTI);
+
+      bool NonUniformIndex = hasNonUniformIndex(IndexOp);
+      Constant *NonUniformOp = ConstantInt::get(Int1Ty, NonUniformIndex);
+
+      std::array<Value *, 3> Args{IndexOp, IsSamplerHeap, NonUniformOp};
+      Expected<CallInst *> OpCreateHandle = OpBuilder.tryCreateOp(
+          OpCode::CreateHandleFromHeap, Args, CI->getName());
+      if (Error E = OpCreateHandle.takeError())
+        return E;
+
+      std::array<Value *, 2> AnnotateArgs{
+          *OpCreateHandle, OpBuilder.getResProps(Props.first, Props.second)};
+      Expected<CallInst *> OpAnnotate = OpBuilder.tryCreateOp(
+          OpCode::AnnotateHandle, AnnotateArgs,
+          CI->hasName() ? CI->getName() + "_annot" : Twine());
+      if (Error E = OpAnnotate.takeError())
+        return E;
+
+      Value *Cast = createTmpHandleCast(*OpAnnotate, CI->getType());
+      CI->replaceAllUsesWith(Cast);
+      CI->eraseFromParent();
+      return Error::success();
+    });
+  }
+
   /// Replace uses of \c Intrin with the values in the `dx.ResRet` of \c Op.
   /// Since we expect to be post-scalarization, make an effort to avoid vectors.
   Error replaceResRetUses(CallInst *Intrin, CallInst *Op, bool HasCheckBit) {
@@ -1281,6 +1323,9 @@ class OpLowerer {
       case Intrinsic::dx_resource_handlefrombinding:
         HasErrors |= lowerHandleFromBinding(F);
         break;
+      case Intrinsic::dx_resource_handlefromheap:
+        HasErrors |= lowerHandleFromHeap(F);
+        break;
       case Intrinsic::dx_resource_getbasepointer:
       case Intrinsic::dx_resource_getpointer:
         HasErrors |= lowerGetPointer(F);
diff --git a/llvm/test/CodeGen/DirectX/CreateHandleHeap-NURI.ll b/llvm/test/CodeGen/DirectX/CreateHandleHeap-NURI.ll
new file mode 100644
index 0000000000000..ab77035da3616
--- /dev/null
+++ b/llvm/test/CodeGen/DirectX/CreateHandleHeap-NURI.ll
@@ -0,0 +1,33 @@
+; RUN: opt -S -passes=dxil-op-lower %s | FileCheck %s
+
+target triple = "dxil-pc-shadermodel6.6-compute"
+
+declare i32 @some_val();
+
+define void @test_with_nuri() {
+
+  %val = call i32 @some_val()
+  %foo = alloca i32, align 4
+
+  ; int val = some_val();
+  ; RWBuffer<float4> Buf = ResourceDescriptorHeap[NonUniformResourceIndex(val)]
+  %nuri = tail call noundef i32 @llvm.dx.resource.nonuniformindex(i32 %val)
+  %typed0 = call target("dx.TypedBuffer", <4 x float>, 1, 0, 0)
+              @llvm.dx.resource.handlefromheap.tdx.TypedBuffer_v4f32_1_0_0(i32 %nuri, i1 false)
+  ; CHECK: [[HANDLE0:%.*]] = call %dx.types.Handle @dx.op.createHandleFromHeap(i32 218, i32 %val, i1 false, i1 true)
+  ; CHECK: [[ANNOT_HANDLE0:%.*]] = call %dx.types.Handle @dx.op.annotateHandle(i32 216, %dx.types.Handle [[HANDLE0]], %dx.types.ResourceProperties { i32 4106, i32 1033 })
+
+  ; SamplerState Samp = SamplerDescriptorHeap[NonUniformResourceIndex(val + 1) % 10];
+  %add1 = add i32 %val, 1
+  %nuri2 = tail call noundef i32 @llvm.dx.resource.nonuniformindex(i32 %add1)
+  %rem1 = urem i32 %nuri2, 10
+  %samp = call target("dx.Sampler", 0)
+              @llvm.dx.resource.handlefromheap.tdx.Sampler_0(i32 %rem1, i1 true)
+  ; CHECK: [[HANDLE1:%.*]] = call %dx.types.Handle @dx.op.createHandleFromHeap(i32 218, i32 %rem1, i1 true, i1 true)
+  ; CHECK: [[ANNOT_HANDLE1:%.*]] = call %dx.types.Handle @dx.op.annotateHandle(i32 216, %dx.types.Handle [[HANDLE1]], %dx.types.ResourceProperties { i32 14, i32 0 })
+
+  ret void
+}
+
+; CHECK: declare %dx.types.Handle @dx.op.createHandleFromHeap(i32, i32, i1, i1)
+; CHECK: declare %dx.types.Handle @dx.op.annotateHandle(i32, %dx.types.Handle, %dx.types.ResourceProperties)
diff --git a/llvm/test/CodeGen/DirectX/CreateHandleHeap.ll b/llvm/test/CodeGen/DirectX/CreateHandleHeap.ll
new file mode 100644
index 0000000000000..ac7b36a58c0f0
--- /dev/null
+++ b/llvm/test/CodeGen/DirectX/CreateHandleHeap.ll
@@ -0,0 +1,32 @@
+; RUN: opt -S -passes=dxil-op-lower %s | FileCheck %s
+
+target triple = "dxil-pc-shadermodel6.6-compute"
+
+declare i32 @some_val();
+
+define void @test() {
+  ; RWBuffer<float4> Buf = ResourceDescriptorHeap[3]
+  %typed = call target("dx.TypedBuffer", <4 x float>, 1, 0, 0)
+              @llvm.dx.resource.handlefromheap.tdx.TypedBuffer_v4f32_1_0_0(i32 3, i1 false)
+  ; CHECK: [[HANDLE0:%.*]] = call %dx.types.Handle @dx.op.createHandleFromHeap(i32 218, i32 3, i1 false, i1 false)
+  ; CHECK: [[ANNOT_HANDLE0:%.*]] = call %dx.types.Handle @dx.op.annotateHandle(i32 216, %dx.types.Handle [[HANDLE0]], %dx.types.ResourceProperties { i32 4106, i32 1033 })
+
+  ; int val = some_val();
+  ; RWBuffer<float4> Buf = ResourceDescriptorHeap[val]
+  %val = call i32 @some_val()
+  %typed1 = call target("dx.TypedBuffer", <4 x float>, 1, 0, 0)
+              @llvm.dx.resource.handlefromheap.tdx.TypedBuffer_v4f32_1_0_0(i32 %val, i1 false)
+  ; CHECK: [[HANDLE0:%.*]] = call %dx.types.Handle @dx.op.createHandleFromHeap(i32 218, i32 %val, i1 false, i1 false)
+  ; CHECK: [[ANNOT_HANDLE0:%.*]] = call %dx.types.Handle @dx.op.annotateHandle(i32 216, %dx.types.Handle [[HANDLE0]], %dx.types.ResourceProperties { i32 4106, i32 1033 })
+
+  ; SamplerState Samp = SamplerDescriptorHeap[val];
+  %samp = call target("dx.Sampler", 0)
+              @llvm.dx.resource.handlefromheap.tdx.Sampler_0(i32 %val, i1 true)
+  ; CHECK: [[HANDLE1:%.*]] = call %dx.types.Handle @dx.op.createHandleFromHeap(i32 218, i32 %val, i1 true, i1 false)
+  ; CHECK: [[ANNOT_HANDLE1:%.*]] = call %dx.types.Handle @dx.op.annotateHandle(i32 216, %dx.types.Handle [[HANDLE1]], %dx.types.ResourceProperties { i32 14, i32 0 })
+
+  ret void
+}
+
+; CHECK: declare %dx.types.Handle @dx.op.createHandleFromHeap(i32, i32, i1, i1)
+; CHECK: declare %dx.types.Handle @dx.op.annotateHandle(i32, %dx.types.Handle, %dx.types.ResourceProperties)

``````````

</details>


https://github.com/llvm/llvm-project/pull/216459


More information about the llvm-branch-commits mailing list