According to one embodiment, an occurrence of an instruction is fetched. The instruction's format specifies its only source operand from a single vector write mask register, and specifies as its destination a single general purpose register. In addition, the instruction's format includes a first field whose contents selects the single vector write mask register, and includes a second field whose contents selects the single general purpose register. The source operand is a write mask including a plurality of one bit vector write mask elements that correspond to different multi-bit data element positions within architectural vector registers. The method also includes, responsive to executing the single occurrence of the single instruction, storing data in the single general purpose register such that its contents represent either a first or second scalar constant based on whether the plurality of one bit vector write mask elements in the source operand are all zero.