Store μops

Store instructions are those that write the contents of a processor register to memory.

Stores Are Handled by the Store Buffers

Background” on page 1070 introduced the Store Buffers.

Store instructions are executed in strict program order and are never executed speculatively. Figure 41-2 on page 1073 pictures the Store execution units:

  • On an integer store operation, the double-speed ALU on port 0 executes the Store Data μop. The Store Address execution unit on port 3 simultaneously executes the Store Address μop.

  • On a FP, SSE or SSE2 store operation, the FP Move execution unit on port 1 executes the Store Data μop. The Store Address execution unit on port 3 simultaneously executes the Store Address μop.

Figure 41-2. The Store Execution ...

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