[DirectX] Add llvm.dx.resource.getdimensions.x intrinsic and lowering to DXIL
#161753
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
…etDimensions DXIL op Closes llvm#112982
|
@llvm/pr-subscribers-llvm-ir @llvm/pr-subscribers-backend-directx Author: Helena Kotas (hekota) ChangesIntroduces LLVM intrinsic Closes #112982 Full diff: https://github.com/llvm/llvm-project/pull/161753.diff 5 Files Affected:
diff --git a/llvm/include/llvm/IR/IntrinsicsDirectX.td b/llvm/include/llvm/IR/IntrinsicsDirectX.td
index 570d6bc35cbd0..38cd3f3e07a87 100644
--- a/llvm/include/llvm/IR/IntrinsicsDirectX.td
+++ b/llvm/include/llvm/IR/IntrinsicsDirectX.td
@@ -77,6 +77,10 @@ def int_dx_resource_updatecounter
: DefaultAttrsIntrinsic<[llvm_i32_ty], [llvm_any_ty, llvm_i8_ty],
[IntrInaccessibleMemOrArgMemOnly]>;
+def int_dx_resource_getdimensions
+ : DefaultAttrsIntrinsic<[llvm_i32_ty, llvm_i32_ty, llvm_i32_ty, llvm_i32_ty], [llvm_any_ty, llvm_i32_ty],
+ [IntrReadMem]>;
+
// Cast between target extension handle types and dxil-style opaque handles
def int_dx_resource_casthandle : Intrinsic<[llvm_any_ty], [llvm_any_ty]>;
diff --git a/llvm/lib/Target/DirectX/DXIL.td b/llvm/lib/Target/DirectX/DXIL.td
index 228114c5c24b2..44c48305f2832 100644
--- a/llvm/lib/Target/DirectX/DXIL.td
+++ b/llvm/lib/Target/DirectX/DXIL.td
@@ -57,6 +57,7 @@ def ResBindTy : DXILOpParamType;
def ResPropsTy : DXILOpParamType;
def SplitDoubleTy : DXILOpParamType;
def BinaryWithCarryTy : DXILOpParamType;
+def DimensionsTy : DXILOpParamType;
class DXILOpClass;
@@ -901,6 +902,13 @@ def CheckAccessFullyMapped : DXILOp<71, checkAccessFullyMapped> {
let attributes = [Attributes<DXIL1_0, [ReadOnly]>];
}
+def GetDimensions : DXILOp<72, getDimensions> {
+ let Doc = "gets the dimensions of a buffer or texture";
+ let arguments = [HandleTy, Int32Ty];
+ let result = DimensionsTy;
+ let stages = [Stages<DXIL1_0, [all_stages]>];
+}
+
def Barrier : DXILOp<80, barrier> {
let Doc = "inserts a memory barrier in the shader";
let intrinsics = [
diff --git a/llvm/lib/Target/DirectX/DXILOpBuilder.cpp b/llvm/lib/Target/DirectX/DXILOpBuilder.cpp
index 1aed8f9867231..944b2e6433988 100644
--- a/llvm/lib/Target/DirectX/DXILOpBuilder.cpp
+++ b/llvm/lib/Target/DirectX/DXILOpBuilder.cpp
@@ -261,6 +261,12 @@ static StructType *getBinaryWithCarryType(LLVMContext &Context) {
return StructType::create({Int32Ty, Int1Ty}, "dx.types.i32c");
}
+static StructType *getDimensionsType(LLVMContext &Ctx) {
+ Type *Int32Ty = Type::getInt32Ty(Ctx);
+ return getOrCreateStructType("dx.types.Dimensions",
+ {Int32Ty, Int32Ty, Int32Ty, Int32Ty}, Ctx);
+}
+
static Type *getTypeFromOpParamType(OpParamType Kind, LLVMContext &Ctx,
Type *OverloadTy) {
switch (Kind) {
@@ -318,6 +324,8 @@ static Type *getTypeFromOpParamType(OpParamType Kind, LLVMContext &Ctx,
return getSplitDoubleType(Ctx);
case OpParamType::BinaryWithCarryTy:
return getBinaryWithCarryType(Ctx);
+ case OpParamType::DimensionsTy:
+ return getDimensionsType(Ctx);
}
llvm_unreachable("Invalid parameter kind");
return nullptr;
diff --git a/llvm/lib/Target/DirectX/DXILOpLowering.cpp b/llvm/lib/Target/DirectX/DXILOpLowering.cpp
index 610d8b63bba27..34bb450bce7d0 100644
--- a/llvm/lib/Target/DirectX/DXILOpLowering.cpp
+++ b/llvm/lib/Target/DirectX/DXILOpLowering.cpp
@@ -627,6 +627,30 @@ class OpLowerer {
});
}
+ [[nodiscard]] bool lowerGetDimensions(Function &F) {
+ IRBuilder<> &IRB = OpBuilder.getIRB();
+ Type *Int32Ty = IRB.getInt32Ty();
+
+ return replaceFunction(F, [&](CallInst *CI) -> Error {
+ IRB.SetInsertPoint(CI);
+ Value *Handle =
+ createTmpHandleCast(CI->getArgOperand(0), OpBuilder.getHandleType());
+ Value *Op1 = CI->getArgOperand(1);
+ if (isa<llvm::PoisonValue>(Op1))
+ Op1 = UndefValue::get(Int32Ty);
+
+ Expected<CallInst *> OpCall = OpBuilder.tryCreateOp(
+ OpCode::GetDimensions, {Handle, Op1}, CI->getName(), Int32Ty);
+ if (Error E = OpCall.takeError())
+ return E;
+ if (Error E = replaceNamedStructUses(CI, *OpCall))
+ return E;
+
+ CI->eraseFromParent();
+ return Error::success();
+ });
+ }
+
[[nodiscard]] bool lowerGetPointer(Function &F) {
// These should have already been handled in DXILResourceAccess, so we can
// just clean up the dead prototype.
@@ -934,6 +958,9 @@ class OpLowerer {
case Intrinsic::dx_resource_updatecounter:
HasErrors |= lowerUpdateCounter(F);
break;
+ case Intrinsic::dx_resource_getdimensions:
+ HasErrors |= lowerGetDimensions(F);
+ break;
case Intrinsic::ctpop:
HasErrors |= lowerCtpopToCountBits(F);
break;
diff --git a/llvm/test/CodeGen/DirectX/bufferGetDimensions.ll b/llvm/test/CodeGen/DirectX/bufferGetDimensions.ll
new file mode 100644
index 0000000000000..7805426181b35
--- /dev/null
+++ b/llvm/test/CodeGen/DirectX/bufferGetDimensions.ll
@@ -0,0 +1,34 @@
+; RUN: opt -S -dxil-op-lower %s | FileCheck %s
+
+target triple = "dxil-pc-shadermodel6.6-compute"
+
+define i32 @test_getdimensions_no_mips() {
+ ; CHECK: [[HANDLE1:%.*]] = call %dx.types.Handle @dx.op.createHandleFromBinding(i32 217,
+ ; CHECK-NEXT: [[ANNOT_HANDLE1:%.*]] = call %dx.types.Handle @dx.op.annotateHandle(i32 216, %dx.types.Handle [[HANDLE1]]
+ %handle1 = call target("dx.TypedBuffer", <4 x float>, 0, 0, 0) @llvm.dx.resource.handlefrombinding(i32 0, i32 0, i32 1, i32 0, ptr null)
+
+ ; CHECK-NEXT: [[RETVAL1:%.*]] = call %dx.types.Dimensions @dx.op.getDimensions(i32 72, %dx.types.Handle [[ANNOT_HANDLE1]], i32 undef)
+ %1 = call { i32, i32, i32, i32 } @llvm.dx.resource.getdimensions.tdx.RawBuffer_i32_1_0t(target("dx.TypedBuffer", <4 x float>, 0, 0, 0) %handle1, i32 poison)
+
+ ; CHECK-NEXT: %[[DIM1:.*]] = extractvalue %dx.types.Dimensions [[RETVAL1]], 0
+ %2 = extractvalue { i32, i32, i32, i32 } %1, 0
+
+ ; CHECK-NEXT: ret i32 %[[DIM1]]
+ ret i32 %2
+}
+
+
+define i32 @test_getdimensions_with_0_mips() {
+ ; CHECK: [[HANDLE2:%.*]] = call %dx.types.Handle @dx.op.createHandleFromBinding(i32 217,
+ ; CHECK-NEXT: [[ANNOT_HANDLE2:%.*]] = call %dx.types.Handle @dx.op.annotateHandle(i32 216, %dx.types.Handle [[HANDLE2]]
+ %handle1 = call target("dx.RawBuffer", float, 0, 0) @llvm.dx.resource.handlefrombinding(i32 0, i32 0, i32 1, i32 0, ptr null)
+
+ ; CHECK-NEXT: [[RETVAL2:%.*]] = call %dx.types.Dimensions @dx.op.getDimensions(i32 72, %dx.types.Handle [[ANNOT_HANDLE2]], i32 0)
+ %1 = call { i32, i32, i32, i32 } @llvm.dx.resource.getdimensions.tdx.RawBuffer_i32_1_0t(target("dx.RawBuffer", float, 0, 0) %handle1, i32 0)
+
+ ; CHECK-NEXT: %[[DIM2:.*]] = extractvalue %dx.types.Dimensions [[RETVAL2]], 0
+ %2 = extractvalue { i32, i32, i32, i32 } %1, 0
+
+ ; CHECK-NEXT: ret i32 %[[DIM2]]
+ ret i32 %2
+}
|
hekota
changed the title
llvm.dx.resource.getdimensions intrinsics and lowering to DXIL
hekota
changed the title
llvm.dx.resource.getdimensions intrinsics and lowering to DXILllvm.dx.resource.getdimensions intrinsic and lowering to DXIL
You can test this locally with the following command:git diff -U0 --pickaxe-regex -S '([^a-zA-Z0-9#_-]undef[^a-zA-Z0-9_-]|UndefValue::get)' 'HEAD~1' HEAD llvm/test/CodeGen/DirectX/bufferGetDimensions.ll llvm/lib/Target/DirectX/DXILOpBuilder.cpp llvm/lib/Target/DirectX/DXILOpLowering.cppThe following files introduce new uses of undef:
Undef is now deprecated and should only be used in the rare cases where no replacement is possible. For example, a load of uninitialized memory yields In tests, avoid using For example, this is considered a bad practice: define void @fn() {
...
br i1 undef, ...
}Please use the following instead: define void @fn(i1 %cond) {
...
br i1 %cond, ...
}Please refer to the Undefined Behavior Manual for more information. |
bogner
reviewed
Oct 8, 2025
There was a problem hiding this comment.
Generally looks good, but I'd like some extra validation since this op has a rather complicated contract, and we should also add a blurb to llvm's DXILResources.rst about the intrinsic and the way it's validated.
bob80905
reviewed
Oct 8, 2025
hekota
changed the title
llvm.dx.resource.getdimensions intrinsic and lowering to DXILllvm.dx.resource.getdimensions.buffer intrinsic and lowering to DXIL
bogner
approved these changes
Oct 9, 2025
|
PR title needs update now that we've gone with |
hekota
changed the title
llvm.dx.resource.getdimensions.buffer intrinsic and lowering to DXILllvm.dx.resource.getdimensions.x intrinsic and lowering to DXIL
llvm-beanz
approved these changes
Oct 14, 2025
There was a problem hiding this comment.
Serious praise here: It is fantastic that we're keeping docs updated with this work! This both makes it easier as a reviewer to make sure the change is correct, and will make it easier for contributors coming into the project.
There was a problem hiding this comment.
Kudos goes to @bogner, he nudged me to do that :)
farzonl
approved these changes
Oct 15, 2025
tex3d
reviewed
Oct 15, 2025
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/3/builds/23482 Here is the relevant piece of the build log for the reference |
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/65/builds/24058 Here is the relevant piece of the build log for the reference |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
8 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Introduces LLVM intrinsic
llvm.dx.resource.getdimensions.xand its lowering to DXIL opop.dx.getDimensions.The intrinsic will be used to implement
GetDimensionfor buffers.Proposal update: llvm/wg-hlsl#350
Closes #112982