GlobalVariable class missing 'attributes' parameter

[varun-r-mallya]

The GlobalVariable class in llvmlite does not support setting attributes on global variables, which is a feature available in LLVM IR.

The GlobalVariable class constructor and instance do not have an attributes parameter or property currently:

https://github.com/numba/llvmlite/blob/7c0e103ffeab6d8d877d8c90cde5fd0aa7be890c/llvmlite/ir/values.py#L789

[gmarkall]

Thanks for the feature request! This seems like a good feature to be able to use. We would like to implement it, but probably won't have the time to do so in time for the next release; I'm putting it in the 0.47 milestone, with the aim of implementing this after the next release.

[sklam]

Leaving note for implementor:

We should try to model the python API like the LLVM C-API

Attribute insertion: https://llvm.org/doxygen/group__LLVMCCoreValueFunction.html

LLVM_C_ABI void 	LLVMAddAttributeAtIndex (LLVMValueRef F, LLVMAttributeIndex Idx, LLVMAttributeRef A)
LLVM_C_ABI unsigned 	LLVMGetAttributeCountAtIndex (LLVMValueRef F, LLVMAttributeIndex Idx)
LLVM_C_ABI void 	LLVMGetAttributesAtIndex (LLVMValueRef F, LLVMAttributeIndex Idx, LLVMAttributeRef *Attrs)
LLVM_C_ABI LLVMAttributeRef 	LLVMGetEnumAttributeAtIndex (LLVMValueRef F, LLVMAttributeIndex Idx, unsigned KindID)
LLVM_C_ABI LLVMAttributeRef 	LLVMGetStringAttributeAtIndex (LLVMValueRef F, LLVMAttributeIndex Idx, const char *K, unsigned KLen)
LLVM_C_ABI void 	LLVMRemoveEnumAttributeAtIndex (LLVMValueRef F, LLVMAttributeIndex Idx, unsigned KindID)
LLVM_C_ABI void 	LLVMRemoveStringAttributeAtIndex (LLVMValueRef F, LLVMAttributeIndex Idx, const char *K, unsigned KLen)
LLVM_C_ABI void 	LLVMAddTargetDependentFunctionAttr (LLVMValueRef Fn, const char *A, const char *V)

Attribute creation: https://llvm.org/doxygen/group__LLVMCCoreContext.html

LLVM_C_ABI unsigned 	LLVMGetEnumAttributeKindForName (const char *Name, size_t SLen)
LLVM_C_ABI unsigned 	LLVMGetLastEnumAttributeKind (void)
LLVM_C_ABI LLVMAttributeRef 	LLVMCreateEnumAttribute (LLVMContextRef C, unsigned KindID, uint64_t Val)
LLVM_C_ABI unsigned 	LLVMGetEnumAttributeKind (LLVMAttributeRef A)
LLVM_C_ABI uint64_t 	LLVMGetEnumAttributeValue (LLVMAttributeRef A)
LLVM_C_ABI LLVMAttributeRef 	LLVMCreateTypeAttribute (LLVMContextRef C, unsigned KindID, LLVMTypeRef type_ref)
LLVM_C_ABI LLVMTypeRef 	LLVMGetTypeAttributeValue (LLVMAttributeRef A)
LLVM_C_ABI LLVMAttributeRef 	LLVMCreateConstantRangeAttribute (LLVMContextRef C, unsigned KindID, unsigned NumBits, const uint64_t LowerWords[], const uint64_t UpperWords[])
LLVM_C_ABI LLVMAttributeRef 	LLVMCreateStringAttribute (LLVMContextRef C, const char *K, unsigned KLength, const char *V, unsigned VLength)
LLVM_C_ABI const char * 	LLVMGetStringAttributeKind (LLVMAttributeRef A, unsigned *Length)
LLVM_C_ABI const char * 	LLVMGetStringAttributeValue (LLVMAttributeRef A, unsigned *Length)
LLVM_C_ABI LLVMBool 	LLVMIsEnumAttribute (LLVMAttributeRef A)
LLVM_C_ABI LLVMBool 	LLVMIsStringAttribute (LLVMAttributeRef A)