gcc/doc/gcc/extensions-to-the-c-language-family/declaring-attributes-of-functions/h8-300-function-attributes.rst

   1 ..
   2   Copyright 1988-2022 Free Software Foundation, Inc.
   3   This is part of the GCC manual.
   4   For copying conditions, see the copyright.rst file.
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   6 .. _h8-300-function-attributes:
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   8 H8/300 Function Attributes
   9 ^^^^^^^^^^^^^^^^^^^^^^^^^^
  10
  11 These function attributes are available for H8/300 targets:
  12
  13 .. index:: function_vector function attribute, H8/300
  14
  15 .. h8-300-fn-attr:: function_vector
  16
  17   Use this attribute on the H8/300, H8/300H, and H8S to indicate
  18   that the specified function should be called through the function vector.
  19   Calling a function through the function vector reduces code size; however,
  20   the function vector has a limited size (maximum 128 entries on the H8/300
  21   and 64 entries on the H8/300H and H8S)
  22   and shares space with the interrupt vector.
  23
  24 .. index:: interrupt_handler function attribute, H8/300
  25
  26 .. h8-300-fn-attr:: interrupt_handler
  27
  28   Use this attribute on the H8/300, H8/300H, and H8S to
  29   indicate that the specified function is an interrupt handler.  The compiler
  30   generates function entry and exit sequences suitable for use in an
  31   interrupt handler when this attribute is present.
  32
  33 .. index:: saveall function attribute, H8/300, save all registers on the H8/300, H8/300H, and H8S
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  35 .. h8-300-fn-attr:: saveall
  36
  37   Use this attribute on the H8/300, H8/300H, and H8S to indicate that
  38   all registers except the stack pointer should be saved in the prologue
  39   regardless of whether they are used or not.