OpenMP: add allocsize(0) attribute to __kmpc_alloc_shared

[durin42]

Summary

This is the second step in obviating two columns about allocation
functions in MemoryBuiltins.cpp.

[jdoerfert]

LG, if the rest gets in.

llvm/include/llvm/Frontend/OpenMP/OMPKinds.def

 __OMP_RTL(__last, false, Void, )
 
 #undef __OMP_RTL
 #undef OMP_RTL
 
 #define ParamAttrs(...) ArrayRef<AttributeSet>({__VA_ARGS__})
 #define EnumAttr(Kind) Attribute::get(Ctx, Attribute::AttrKind::Kind)
 #define EnumAttrInt(Kind, N) Attribute::get(Ctx, Attribute::AttrKind::Kind, N)
+#define AllocSizeAttr(N, M) Attribute::getWithAllocSizeArgs(Ctx, N, M)
 #define AttributeSet(...)                                                      \
   AttributeSet::get(Ctx, ArrayRef<Attribute>({__VA_ARGS__}))
 
 #ifndef OMP_ATTRS_SET
 #define OMP_ATTRS_SET(VarName, AttrSet)
 #endif
 
 #define __OMP_ATTRS_SET(VarName, AttrSet) OMP_ATTRS_SET(VarName, AttrSet)
__OMP_RTL_ATTRS(__kmpc_doacross_init, BarrierAttrs, AttributeSet(),
                 ParamAttrs(ReadOnlyPtrAttrs))
 __OMP_RTL_ATTRS(__kmpc_doacross_post, BarrierAttrs, AttributeSet(),
                 ParamAttrs(ReadOnlyPtrAttrs, AttributeSet(), ReadOnlyPtrAttrs))
 __OMP_RTL_ATTRS(__kmpc_doacross_wait, BarrierAttrs, AttributeSet(),
                 ParamAttrs(ReadOnlyPtrAttrs, AttributeSet(), ReadOnlyPtrAttrs))
 __OMP_RTL_ATTRS(__kmpc_doacross_fini, BarrierAttrs, AttributeSet(),
                 ParamAttrs(ReadOnlyPtrAttrs))
 
-__OMP_RTL_ATTRS(__kmpc_alloc_shared, DeviceAllocAttrs, ReturnPtrAttrs,
-                ParamAttrs())
+__OMP_RTL_ATTRS(__kmpc_alloc_shared, AttributeSet(
+  EnumAttr(NoUnwind),
+  EnumAttr(NoSync), 
+  AllocSizeAttr(0, None)), ReturnPtrAttrs, ParamAttrs())
 __OMP_RTL_ATTRS(__kmpc_free_shared, DeviceAllocAttrs, AttributeSet(),
                 ParamAttrs(NoCaptureAttrs))
 
 __OMP_RTL_ATTRS(__kmpc_alloc, DefaultAttrs, ReturnPtrAttrs, ParamAttrs())
 __OMP_RTL_ATTRS(__kmpc_aligned_alloc, DefaultAttrs, ReturnPtrAttrs,
                 ParamAttrs())
 __OMP_RTL_ATTRS(__kmpc_free, AllocAttrs, AttributeSet(), ParamAttrs())
 
__OMP_RTL_ATTRS(__kmpc_parallel_51, AlwaysInlineAttrs, AttributeSet(),
                 ParamAttrs())
 
 #undef __OMP_RTL_ATTRS
 #undef OMP_RTL_ATTRS
 #undef AttributeSet
 #undef EnumAttr
 #undef EnumAttrInt
 #undef ParamAttrs
+#undef AllocSizeAttr
 
 ///}
 
 /// KMP ident_t bit flags
 ///
 /// In accordance with the values in `openmp/runtime/src/kmp.h`.
 ///
 ///{

llvm/test/Transforms/OpenMP/spmdization.ll

 !30 = !{!31, !27, i64 0}
 !31 = !{!"kmp_task_t_with_privates", !32, i64 0}
 !32 = !{!"kmp_task_t", !27, i64 0, !27, i64 8, !19, i64 16, !20, i64 24, !20, i64 32}
 ;.
 ; AMDGPU: attributes #[[ATTR0]] = { alwaysinline convergent norecurse nounwind }
 ; AMDGPU: attributes #[[ATTR1]] = { convergent norecurse nounwind }
 ; AMDGPU: attributes #[[ATTR2]] = { nounwind }
 ; AMDGPU: attributes #[[ATTR3:[0-9]+]] = { nosync nounwind }
-; AMDGPU: attributes #[[ATTR4:[0-9]+]] = { nofree nosync nounwind }
+; AMDGPU: attributes #[[ATTR4:[0-9]+]] = { nofree nosync nounwind allocsize(0) }
 ; AMDGPU: attributes #[[ATTR5]] = { convergent "llvm.assume"="ompx_spmd_amenable" }
 ; AMDGPU: attributes #[[ATTR6]] = { convergent }
 ; AMDGPU: attributes #[[ATTR7:[0-9]+]] = { argmemonly nofree nosync nounwind willreturn }
 ; AMDGPU: attributes #[[ATTR8:[0-9]+]] = { alwaysinline }
 ; AMDGPU: attributes #[[ATTR9:[0-9]+]] = { convergent nounwind }
 ;.
 ; NVPTX: attributes #[[ATTR0]] = { alwaysinline convergent norecurse nounwind }
 ; NVPTX: attributes #[[ATTR1]] = { convergent norecurse nounwind }
 ; NVPTX: attributes #[[ATTR2]] = { nounwind }
 ; NVPTX: attributes #[[ATTR3:[0-9]+]] = { nosync nounwind }
-; NVPTX: attributes #[[ATTR4:[0-9]+]] = { nofree nosync nounwind }
+; NVPTX: attributes #[[ATTR4:[0-9]+]] = { nofree nosync nounwind allocsize(0) }
 ; NVPTX: attributes #[[ATTR5]] = { convergent "llvm.assume"="ompx_spmd_amenable" }
 ; NVPTX: attributes #[[ATTR6]] = { convergent }
 ; NVPTX: attributes #[[ATTR7:[0-9]+]] = { argmemonly nofree nosync nounwind willreturn }
 ; NVPTX: attributes #[[ATTR8:[0-9]+]] = { alwaysinline }
 ; NVPTX: attributes #[[ATTR9:[0-9]+]] = { convergent nounwind }
 ;.
 ; AMDGPU-DISABLED: attributes #[[ATTR0]] = { alwaysinline convergent norecurse nounwind }
 ; AMDGPU-DISABLED: attributes #[[ATTR1]] = { convergent norecurse nounwind }
 ; AMDGPU-DISABLED: attributes #[[ATTR2]] = { nounwind }
 ; AMDGPU-DISABLED: attributes #[[ATTR3:[0-9]+]] = { nosync nounwind }
-; AMDGPU-DISABLED: attributes #[[ATTR4:[0-9]+]] = { nofree nosync nounwind }
+; AMDGPU-DISABLED: attributes #[[ATTR4:[0-9]+]] = { nofree nosync nounwind allocsize(0) }
 ; AMDGPU-DISABLED: attributes #[[ATTR5]] = { convergent "llvm.assume"="ompx_spmd_amenable" }
 ; AMDGPU-DISABLED: attributes #[[ATTR6]] = { convergent }
 ; AMDGPU-DISABLED: attributes #[[ATTR7:[0-9]+]] = { argmemonly nofree nosync nounwind willreturn }
 ; AMDGPU-DISABLED: attributes #[[ATTR8:[0-9]+]] = { alwaysinline }
 ; AMDGPU-DISABLED: attributes #[[ATTR9:[0-9]+]] = { convergent nounwind }
 ;.
 ; NVPTX-DISABLED: attributes #[[ATTR0]] = { alwaysinline convergent norecurse nounwind }
 ; NVPTX-DISABLED: attributes #[[ATTR1]] = { convergent norecurse nounwind }
 ; NVPTX-DISABLED: attributes #[[ATTR2]] = { nounwind }
 ; NVPTX-DISABLED: attributes #[[ATTR3:[0-9]+]] = { nosync nounwind }
-; NVPTX-DISABLED: attributes #[[ATTR4:[0-9]+]] = { nofree nosync nounwind }
+; NVPTX-DISABLED: attributes #[[ATTR4:[0-9]+]] = { nofree nosync nounwind allocsize(0) }
 ; NVPTX-DISABLED: attributes #[[ATTR5]] = { convergent "llvm.assume"="ompx_spmd_amenable" }
 ; NVPTX-DISABLED: attributes #[[ATTR6]] = { convergent }
 ; NVPTX-DISABLED: attributes #[[ATTR7:[0-9]+]] = { argmemonly nofree nosync nounwind willreturn }
 ; NVPTX-DISABLED: attributes #[[ATTR8:[0-9]+]] = { alwaysinline }
 ; NVPTX-DISABLED: attributes #[[ATTR9:[0-9]+]] = { convergent nounwind }
 ;.
 ; AMDGPU: [[META0:![0-9]+]] = !{i32 0, i32 64770, i32 541341486, !"do_not_spmdize_task", i32 74, i32 5}
 ; AMDGPU: [[META1:![0-9]+]] = !{i32 0, i32 64770, i32 541341486, !"sequential_loop_to_stack_var", i32 20, i32 1}