7.4.4. Tracing LSMs

When the first data transfer associated with an LSM is traced, a Normal data packet, or an Out-of-order placeholder packet, is placed in the FIFO. If data address tracing is enabled this packet includes the data address. All subsequent data transfers for that LSM place a packet in the FIFO according to the following rules:

A compiler can combine adjacent loads or stores into an LSM to speed up execution. In ETMv1, data tracing can be enabled only at the beginning of a Load/Store Multiple (LSM) instruction. ETMv2 and ETMv3 can partially trace an LSM and output only the data values that match the filtering criteria. For example, the ViewData setting might match only from the third word of the LSM. In this case this third transfer is the first transfer traced for the LSM, and if data address tracing is enabled the trace packet includes the data address of the third word of the LSM.

For more information about tracing LSMs in data-only mode see Tracing LSM instructions in data-only mode.

See Load/Store Multiple (LSM) instructions for a list of the LSM instructions.

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