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(as.info)Opcodes for i860

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i860 Opcodes
------------

   All of the Intel i860 machine instructions are supported. Please see
either _i860 Microprocessor Programmer's Reference Manual_ or _i860
Microprocessor Architecture_ for more information.

Other instruction support (pseudo-instructions)
...............................................

   For compatibility with some other i860 assemblers, a number of
pseudo-instructions are supported. While these are supported, they are
a very undesirable feature that should be avoided - in particular, when
they result in an expansion to multiple actual i860 instructions. Below
are the pseudo-instructions that result in expansions.
   * Load large immediate into general register:

     The pseudo-instruction `mov imm,%rn' (where the immediate does not
     fit within a signed 16-bit field) will be expanded into:
          orh large_imm@h,%r0,%rn
          or large_imm@l,%rn,%rn

   * Load/store with relocatable address expression:

     For example, the pseudo-instruction `ld.b addr,%rn' will be
     expanded into:
          orh addr_exp@ha,%r0,%r31
          ld.l addr_exp@l(%r31),%rn

     The analogous expansions apply to `ld.x, st.x, fld.x, pfld.x,
     fst.x', and `pst.x' as well.

   * Signed large immediate with add/subtract:

     If any of the arithmetic operations `adds, addu, subs, subu' are
     used with an immediate larger than 16-bits (signed), then they
     will be expanded.  For instance, the pseudo-instruction `adds
     large_imm,%rx,%rn' expands to:
          orh large_imm@h,%r0,%r31
          or large_imm@l,%r31,%r31
          adds %r31,%rx,%rn

   * Unsigned large immediate with logical operations:

     Logical operations (`or, andnot, or, xor') also result in
     expansions.  The pseudo-instruction `or large_imm,%rx,%rn' results
     in:
          orh large_imm@h,%rx,%r31
          or large_imm@l,%r31,%rn

     Similarly for the others, except for `and' which expands to:
          andnot (-1 - large_imm)@h,%rx,%r31
          andnot (-1 - large_imm)@l,%r31,%rn