Author: Finn Plummer Date: 2026-03-02T11:55:09-08:00 New Revision: ed085573f40279d6b9cc5ff6e53e1b08d3c45df3
URL: https://github.com/llvm/llvm-project/commit/ed085573f40279d6b9cc5ff6e53e1b08d3c45df3 DIFF: https://github.com/llvm/llvm-project/commit/ed085573f40279d6b9cc5ff6e53e1b08d3c45df3.diff LOG: [SemaHLSL] Warn when a local resource is re-assigned to non-unique global resource (#182101) Generate a warning whenever a local resource is (re-)assigned such that it is not guaranteed to map to a single unique global resource. An error is not generated during sema because simple DCE or constant folding might resolve the assignment to be to a unique global resource. Instead, an error will be reported when trying to resolve the resource access in the `dxil-resource-access` pass, implemented [here](https://github.com/llvm/llvm-project/pull/182106). Resolves https://github.com/llvm/llvm-project/issues/179303. Added: clang/test/SemaHLSL/local_resource_bindings.hlsl clang/test/SemaHLSL/local_resource_bindings_errs.hlsl Modified: clang/include/clang/Basic/DiagnosticGroups.td clang/include/clang/Basic/DiagnosticSemaKinds.td clang/include/clang/Sema/SemaHLSL.h clang/lib/Sema/SemaHLSL.cpp Removed: ################################################################################ diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td index f5b6a4a9bfa73..5a1b990bd0943 100644 --- a/clang/include/clang/Basic/DiagnosticGroups.td +++ b/clang/include/clang/Basic/DiagnosticGroups.td @@ -1853,6 +1853,9 @@ def HLSLMixPackOffset : DiagGroup<"mix-packoffset">; // Warning for implicit resource bindings. def HLSLImplicitBinding : DiagGroup<"hlsl-implicit-binding">; +// Warning for explicit resource bindings. +def HLSLExplicitBinding : DiagGroup<"hlsl-explicit-binding">; + // Warnings for DXIL validation def DXILValidation : DiagGroup<"dxil-validation">; diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td index ef0e29af0f224..a2d12a3a2c758 100644 --- a/clang/include/clang/Basic/DiagnosticSemaKinds.td +++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -13591,6 +13591,10 @@ def err_hlsl_incomplete_resource_array_in_function_param: Error< "incomplete resource array in a function parameter">; def err_hlsl_assign_to_global_resource: Error< "assignment to global resource variable %0 is not allowed">; +def warn_hlsl_assigning_local_resource_is_not_unique + : Warning<"assignment of %0 to local resource %1 is not to the same " + "unique global resource">, + InGroup<HLSLExplicitBinding>; def err_hlsl_push_constant_unique : Error<"cannot have more than one push constant block">; diff --git a/clang/include/clang/Sema/SemaHLSL.h b/clang/include/clang/Sema/SemaHLSL.h index 020a4dc44ee7f..a6a38531ac284 100644 --- a/clang/include/clang/Sema/SemaHLSL.h +++ b/clang/include/clang/Sema/SemaHLSL.h @@ -132,6 +132,8 @@ class SemaHLSL : public SemaBase { bool ActOnUninitializedVarDecl(VarDecl *D); void ActOnEndOfTranslationUnit(TranslationUnitDecl *TU); void CheckEntryPoint(FunctionDecl *FD); + + // Return true if everything is ok; returns false if there was an error. bool CheckResourceBinOp(BinaryOperatorKind Opc, Expr *LHSExpr, Expr *RHSExpr, SourceLocation Loc); @@ -234,6 +236,12 @@ class SemaHLSL : public SemaBase { // List of all resource bindings ResourceBindings Bindings; + // Map of local resource variables to their assigned global resources. + // + // The binding can be a nullptr, in which case, the variable has yet to be + // initialized or assigned to. + llvm::DenseMap<const VarDecl *, const DeclBindingInfo *> Assigns; + // Global declaration collected for the $Globals default constant // buffer which will be created at the end of the translation unit. llvm::SmallVector<Decl *> DefaultCBufferDecls; @@ -313,6 +321,15 @@ class SemaHLSL : public SemaBase { bool initGlobalResourceDecl(VarDecl *VD); bool initGlobalResourceArrayDecl(VarDecl *VD); + + // Infer a common global binding info for an Expr + // + // Returns std::nullopt if the expr refers to non-unique global bindings. + // Returns nullptr if it refer to any global binding, otherwise it returns + // a reference to the global binding info. + std::optional<const DeclBindingInfo *> inferGlobalBinding(Expr *E); + + void trackLocalResource(VarDecl *VDecl, Expr *E); }; } // namespace clang diff --git a/clang/lib/Sema/SemaHLSL.cpp b/clang/lib/Sema/SemaHLSL.cpp index 911dba40d3bde..804ea70aaddce 100644 --- a/clang/lib/Sema/SemaHLSL.cpp +++ b/clang/lib/Sema/SemaHLSL.cpp @@ -4686,7 +4686,67 @@ bool SemaHLSL::ActOnUninitializedVarDecl(VarDecl *VD) { return false; } -// Return true if everything is ok; returns false if there was an error. +std::optional<const DeclBindingInfo *> SemaHLSL::inferGlobalBinding(Expr *E) { + if (auto *Ternary = dyn_cast<ConditionalOperator>(E)) { + auto TrueInfo = inferGlobalBinding(Ternary->getTrueExpr()); + auto FalseInfo = inferGlobalBinding(Ternary->getFalseExpr()); + if (!TrueInfo || !FalseInfo) + return std::nullopt; + if (*TrueInfo != *FalseInfo) + return std::nullopt; + return TrueInfo; + } + + if (auto *ASE = dyn_cast<ArraySubscriptExpr>(E)) + E = ASE->getBase()->IgnoreParenImpCasts(); + + if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E->IgnoreParens())) + if (VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) { + const Type *Ty = VD->getType()->getUnqualifiedDesugaredType(); + if (Ty->isArrayType()) + Ty = Ty->getArrayElementTypeNoTypeQual(); + + if (const auto *AttrResType = + HLSLAttributedResourceType::findHandleTypeOnResource(Ty)) { + ResourceClass RC = AttrResType->getAttrs().ResourceClass; + return Bindings.getDeclBindingInfo(VD, RC); + } + } + + return nullptr; +} + +void SemaHLSL::trackLocalResource(VarDecl *VD, Expr *E) { + std::optional<const DeclBindingInfo *> ExprBinding = inferGlobalBinding(E); + if (!ExprBinding) { + SemaRef.Diag(E->getBeginLoc(), + diag::warn_hlsl_assigning_local_resource_is_not_unique) + << E << VD; + return; // Expr use multiple resources + } + + if (*ExprBinding == nullptr) + return; // No binding could be inferred to track, return without error + + auto PrevBinding = Assigns.find(VD); + if (PrevBinding == Assigns.end()) { + // No previous binding recorded, simply record the new assignment + Assigns.insert({VD, *ExprBinding}); + return; + } + + // Otherwise, warn if the assignment implies diff erent resource bindings + if (*ExprBinding != PrevBinding->second) { + SemaRef.Diag(E->getBeginLoc(), + diag::warn_hlsl_assigning_local_resource_is_not_unique) + << E << VD; + SemaRef.Diag(VD->getLocation(), diag::note_var_declared_here) << VD; + return; + } + + return; +} + bool SemaHLSL::CheckResourceBinOp(BinaryOperatorKind Opc, Expr *LHSExpr, Expr *RHSExpr, SourceLocation Loc) { assert((LHSExpr->getType()->isHLSLResourceRecord() || @@ -4709,6 +4769,8 @@ bool SemaHLSL::CheckResourceBinOp(BinaryOperatorKind Opc, Expr *LHSExpr, SemaRef.Diag(VD->getLocation(), diag::note_var_declared_here) << VD; return false; } + + trackLocalResource(VD, RHSExpr); } } return true; @@ -5315,6 +5377,10 @@ QualType SemaHLSL::checkMatrixComponent(Sema &S, QualType baseType, } bool SemaHLSL::handleInitialization(VarDecl *VDecl, Expr *&Init) { + // If initializing a local resource, track the resource binding it is using + if (VDecl->getType()->isHLSLResourceRecord() && !VDecl->hasGlobalStorage()) + trackLocalResource(VDecl, Init); + const HLSLVkConstantIdAttr *ConstIdAttr = VDecl->getAttr<HLSLVkConstantIdAttr>(); if (!ConstIdAttr) diff --git a/clang/test/SemaHLSL/local_resource_bindings.hlsl b/clang/test/SemaHLSL/local_resource_bindings.hlsl new file mode 100644 index 0000000000000..58e7bf47d2d0d --- /dev/null +++ b/clang/test/SemaHLSL/local_resource_bindings.hlsl @@ -0,0 +1,62 @@ +// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-library -finclude-default-header -verify %s + +// expected-no-diagnostics + +RWBuffer<uint> In : register(u0); +RWStructuredBuffer<uint> Out0 : register(u1); +RWStructuredBuffer<uint> Out1 : register(u2); +RWStructuredBuffer<uint> OutArr[]; + +cbuffer c { + bool cond; +}; + +void no_initial_assignment(uint idx) { + RWStructuredBuffer<uint> Out; + if (cond) { + Out = Out1; + } + Out[idx] = In[idx]; +} + +void assignment_to_uninitialized(uint idx) { + RWStructuredBuffer<uint> Out; + Out = Out; + Out[idx] = In[idx]; +} + +void same_assignment(uint idx) { + RWStructuredBuffer<uint> Out = Out1; + if (cond) { + Out = Out1; + } + Out[idx] = In[idx]; +} + +void conditional_initialization_with_index(uint idx) { + RWStructuredBuffer<uint> Out = cond ? OutArr[0] : OutArr[1]; + Out[idx] = In[idx]; +} + +void conditional_assignment_with_index(uint idx) { + RWStructuredBuffer<uint> Out; + if (cond) { + Out = OutArr[0]; + } else { + Out = OutArr[1]; + } + Out[idx] = In[idx]; +} + +void reassignment(uint idx) { + RWStructuredBuffer<uint> Out = Out0; + if (cond) { + Out = Out0; + } + Out[idx] = In[idx]; +} + +void conditional_result_in_same(uint idx) { + RWStructuredBuffer<uint> Out = cond ? Out0 : Out0; + Out[idx] = In[idx]; +} diff --git a/clang/test/SemaHLSL/local_resource_bindings_errs.hlsl b/clang/test/SemaHLSL/local_resource_bindings_errs.hlsl new file mode 100644 index 0000000000000..7404e444390b1 --- /dev/null +++ b/clang/test/SemaHLSL/local_resource_bindings_errs.hlsl @@ -0,0 +1,49 @@ +// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-library -finclude-default-header -verify %s + +RWBuffer<uint> In : register(u0); +RWStructuredBuffer<uint> Out0 : register(u1); +RWStructuredBuffer<uint> Out1 : register(u2); +RWStructuredBuffer<uint> OutArr[]; + +cbuffer c { + bool cond; +}; + +void conditional_initialization(uint idx) { + // expected-warning@+1 {{assignment of 'cond ? Out0 : Out1' to local resource 'Out' is not to the same unique global resource}} + RWStructuredBuffer<uint> Out = cond ? Out0 : Out1; + Out[idx] = In[idx]; +} + +void branched_assignment(uint idx) { + RWStructuredBuffer<uint> Out = Out0; // expected-note {{variable 'Out' is declared here}} + if (cond) { + // expected-warning@+1 {{assignment of 'Out1' to local resource 'Out' is not to the same unique global resource}} + Out = Out1; + } + Out[idx] = In[idx]; +} + +void branched_assignment_with_array(uint idx) { + RWStructuredBuffer<uint> Out = Out0; // expected-note {{variable 'Out' is declared here}} + if (cond) { + // expected-warning@+1 {{assignment of 'OutArr[0]' to local resource 'Out' is not to the same unique global resource}} + Out = OutArr[0]; + } + Out[idx] = In[idx]; +} + +void conditional_assignment(uint idx) { + RWStructuredBuffer<uint> Out; + // expected-warning@+1 {{assignment of 'cond ? Out0 : Out1' to local resource 'Out' is not to the same unique global resource}} + Out = cond ? Out0 : Out1; + Out[idx] = In[idx]; +} + +static RWStructuredBuffer<uint> StaticOut; + +void static_conditional_assignment(uint idx) { + // expected-warning@+1 {{assignment of 'cond ? Out0 : Out1' to local resource 'StaticOut' is not to the same unique global resource}} + StaticOut = cond ? Out0 : Out1; + StaticOut[idx] = In[idx]; +} _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
