[nvvm] Mark ldu and ldg intrinsics as IntrArgMemOnly.

[jlebar]

Summary

Previously these intrinsics were marked as can-read any memory address.
Now they're marked as reading only the pointer they're passed.

[jlebar]

Fix typo.

[rnk]

lgtm

include/llvm/IR/IntrinsicsNVVM.td

def int_nvvm_read_ptx_sreg_warpsize :
       Intrinsic<[llvm_i32_ty], [], [IntrNoMem]>,
       GCCBuiltin<"__nvvm_read_ptx_sreg_warpsize">;
 
 
 // Generated within nvvm. Use for ldu on sm_20 or later.  Second arg is the
 // pointer's alignment.
 def int_nvvm_ldu_global_i : Intrinsic<[llvm_anyint_ty],
   [LLVMAnyPointerType<LLVMMatchType<0>>, llvm_i32_ty],
-  [IntrReadMem, NoCapture<0>],
+  [IntrReadMem, IntrArgMemOnly, NoCapture<0>],
   "llvm.nvvm.ldu.global.i">;
 def int_nvvm_ldu_global_f : Intrinsic<[llvm_anyfloat_ty],
   [LLVMAnyPointerType<LLVMMatchType<0>>, llvm_i32_ty],
-  [IntrReadMem, NoCapture<0>],
+  [IntrReadMem, IntrArgMemOnly, NoCapture<0>],
   "llvm.nvvm.ldu.global.f">;
 def int_nvvm_ldu_global_p : Intrinsic<[llvm_anyptr_ty],
   [LLVMAnyPointerType<LLVMMatchType<0>>, llvm_i32_ty],
-  [IntrReadMem, NoCapture<0>],
+  [IntrReadMem, IntrArgMemOnly, NoCapture<0>],
   "llvm.nvvm.ldu.global.p">;
 
 // Generated within nvvm. Use for ldg on sm_35 or later.  Second arg is the
 // pointer's alignment.
 def int_nvvm_ldg_global_i : Intrinsic<[llvm_anyint_ty],
   [LLVMAnyPointerType<LLVMMatchType<0>>, llvm_i32_ty],
-  [IntrReadMem, NoCapture<0>],
+  [IntrReadMem, IntrArgMemOnly, NoCapture<0>],
   "llvm.nvvm.ldg.global.i">;
 def int_nvvm_ldg_global_f : Intrinsic<[llvm_anyfloat_ty],
   [LLVMAnyPointerType<LLVMMatchType<0>>, llvm_i32_ty],
-  [IntrReadMem, NoCapture<0>],
+  [IntrReadMem, IntrArgMemOnly, NoCapture<0>],
   "llvm.nvvm.ldg.global.f">;
 def int_nvvm_ldg_global_p : Intrinsic<[llvm_anyptr_ty],
   [LLVMAnyPointerType<LLVMMatchType<0>>, llvm_i32_ty],
-  [IntrReadMem, NoCapture<0>],
+  [IntrReadMem, IntrArgMemOnly, NoCapture<0>],
   "llvm.nvvm.ldg.global.p">;
 
 // Use for generic pointers
 // - These intrinsics are used to convert address spaces.
 // - The input pointer and output pointer must have the same type, except for
 //   the address-space. (This restriction is not enforced here as there is
 //   currently no way to describe it).
 // - This complements the llvm bitcast, which can be used to cast one type