diff options
Diffstat (limited to 'source/slang/check.cpp')
| -rw-r--r-- | source/slang/check.cpp | 45 |
1 files changed, 34 insertions, 11 deletions
diff --git a/source/slang/check.cpp b/source/slang/check.cpp index 4f914ee1f..38a79f1b7 100644 --- a/source/slang/check.cpp +++ b/source/slang/check.cpp @@ -78,6 +78,28 @@ namespace Slang return isEffectivelyStatic(decl, parentDecl); } + /// Is `decl` a global shader parameter declaration? + bool isGlobalShaderParameter(VarDeclBase* decl) + { + // A global shader parameter must be declared at global (module) scope. + // + if(!dynamic_cast<ModuleDecl*>(decl->ParentDecl)) return false; + + // A global variable marked `static` indicates a traditional + // global variable (albeit one that is implicitly local to + // the translation unit) + // + if(decl->HasModifier<HLSLStaticModifier>()) return false; + + // The `groupshared` modifier indicates that a variable cannot + // be a shader parameters, but is instead transient storage + // allocated for the duration of a thread-group's execution. + // + if(decl->HasModifier<HLSLGroupSharedModifier>()) return false; + + return true; + } + // A flat representation of basic types (scalars, vectors and matrices) // that can be used as lookup key in caches struct BasicTypeKey @@ -4218,17 +4240,6 @@ namespace Slang if (function || checkingPhase == CheckingPhase::Header) { TypeExp typeExp = CheckUsableType(varDecl->type); -#if 0 - if (typeExp.type->GetBindableResourceType() != BindableResourceType::NonBindable) - { - // We don't want to allow bindable resource types as local variables (at least for now). - auto parentDecl = varDecl->ParentDecl; - if (auto parentScopeDecl = dynamic_cast<ScopeDecl*>(parentDecl)) - { - getSink()->diagnose(varDecl->type, Diagnostics::invalidTypeForLocalVariable); - } - } -#endif varDecl->type = typeExp; if (varDecl->type.Equals(getSession()->getVoidType())) { @@ -9015,6 +9026,18 @@ namespace Slang if(varDeclRef.getDecl()->FindModifier<ConstModifier>()) isLValue = false; + // Global-scope shader parameters should not be writable, + // since they are effectively program inputs. + // + // TODO: We could eventually treat a mutable global shader + // parameter as a shorthand for an immutable parameter and + // a global variable that gets initialized from that parameter, + // but in order to do so we'd need to support global variables + // with resource types better in the back-end. + // + if(isGlobalShaderParameter(varDeclRef.getDecl())) + isLValue = false; + qualType.IsLeftValue = isLValue; return qualType; } |