1. A load store queue comprising: a first table which stores in-order information about store instructions; a second table which stores the addresses for and the store values of store instructions, the individual entries in said second table being retrieved by using said addresses as indexes; a first retrieving unit which is connected to said first table and which, according to tag information about a load instruction, retrieves store instructions preceding said load instruction from the in-order information about the store instructions stored in said first table; and a second retrieving unit which is connected between said second table and said first retrieving unit and which outputs a coincidence signal and the store value corresponding to said store instruction as a load value, when the store instruction read from said second table according to the address for said load instruction coincides with the store instruction supplied from said first retrieving unit.