Check for pre-existing types in the context.

Author: maleadt

src/core/module.jl

@@ -77,25 +77,12 @@ set_used!(mod::Module, values::GlobalVariable...) = nothing
 set_compiler_used!(mod::Module, values::GlobalVariable...) = nothing
 end
 
+
 ## type iteration
 
 export types
 
-struct ModuleTypeDict <: AbstractDict{String,LLVMType}
-    mod::Module
-end
-
-types(mod::Module) = ModuleTypeDict(mod)
-
-function Base.haskey(iter::ModuleTypeDict, name::String)
-    return API.LLVMGetTypeByName(iter.mod, name) != C_NULL
-end
-
-function Base.getindex(iter::ModuleTypeDict, name::String)
-    objref = API.LLVMGetTypeByName(iter.mod, name)
-    objref == C_NULL && throw(KeyError(name))
-    return LLVMType(objref)
-end
+@deprecate types(mod::Module) types(context(mod))
 
 
 ## metadata iteration

src/core/type.jl

@@ -272,3 +272,31 @@ identify(::Type{LLVMType}, ::Val{API.LLVMTokenTypeKind}) = TokenType
 
 TokenType(ctx::Context) =
     TokenType(API.LLVMTokenTypeInContext(ctx))
+
+
+## type iteration
+
+export types
+
+struct ContextTypeDict <: AbstractDict{String,LLVMType}
+    ctx::Context
+end
+
+# FIXME: remove on LLVM 12
+function LLVMGetTypeByName2(ctx::Context, name)
+    Module("dummy", ctx) do mod
+        API.LLVMGetTypeByName(mod, name)
+    end
+end
+
+types(ctx::Context) = ContextTypeDict(ctx)
+
+function Base.haskey(iter::ContextTypeDict, name::String)
+    return LLVMGetTypeByName2(iter.ctx, name) != C_NULL
+end
+
+function Base.getindex(iter::ContextTypeDict, name::String)
+    objref = LLVMGetTypeByName2(iter.ctx, name)
+    objref == C_NULL && throw(KeyError(name))
+    return LLVMType(objref)
+end

src/core/value/constant.jl

@@ -206,7 +206,7 @@ ConstantStruct(typ::StructType, values::Vector{<:Constant}) =
     ConstantStruct(API.LLVMConstNamedStruct(typ, values, length(values)))
 
 # create a ConstantStruct from a Julia object
-function ConstantStruct(value::T, ctx::Context=GlobalContext();
+function ConstantStruct(value::T, ctx::Context=GlobalContext(); name=String(nameof(T)),
                         anonymous::Core.Bool=false, packed::Core.Bool=false) where {T}
     isbitstype(T) || throw(ArgumentError("Can only create a ConstantStruct from an isbits struct"))
     constants = Vector{Constant}()
@@ -228,7 +228,9 @@ function ConstantStruct(value::T, ctx::Context=GlobalContext();
     if anonymous
         ConstantStruct(constants, ctx; packed=packed)
     else
-        typ = StructType(String(nameof(T)), ctx)
+        # check if this name already exists in the context
+        haskey(types(ctx), name) && throw(ArgumentError("Type name '$name' is already used in this context. Use a different context, name, or request an anonymous struct."))
+        typ = StructType(name, ctx)
         ConstantStruct(typ, constants)
     end
 end