10.10 Floating-point data types in A32/T32 instructions

Most floating-point instructions use a data type specifier to define the size and type of data that the instruction operates on.

Data type specifiers in floating-point instructions consist of a letter indicating the type of data, usually followed by a number indicating the width. They are separated from the instruction mnemonic by a point.

The following data types are available in floating-point instructions:

F32 (or F)
F64 (or D)

The datatype of the second (or only) operand is specified in the instruction.


  • Most instructions have a restricted range of permitted data types. See the instruction descriptions for details. However, the data type description is flexible:

    • If the description specifies I, you can also use the S or U data types.
    • If only the data size is specified, you can specify a type (S, U, P or F).
    • If no data type is specified, you can specify a data type.
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