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[LangRef] Move catchpad to "Other Operators" (NFC) 

It is no longer a terminator, so should no longer be grouped with them.

llvm-svn: 257276
This commit is contained in:
Joseph Tremoulet 2016-01-10 04:46:10 +00:00
parent a9a05cbcf9
commit 2adaa98927
1 changed files with 68 additions and 68 deletions
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136
llvm/docs/LangRef.rst
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@ -5447,74 +5447,6 @@ Example:
dispatch2: dispatch2:
%cs2 = catchswitch within %parenthandler [label %handler0] unwind label %cleanup %cs2 = catchswitch within %parenthandler [label %handler0] unwind label %cleanup
.. _i_catchpad:
'``catchpad``' Instruction
^^^^^^^^^^^^^^^^^^^^^^^^^^
Syntax:
"""""""
::
<resultval> = catchpad within <catchswitch> [<args>*]
Overview:
"""""""""
The '``catchpad``' instruction is used by `LLVM's exception handling
system <ExceptionHandling.html#overview>`_ to specify that a basic block
begins a catch handler --- one where a personality routine attempts to transfer
control to catch an exception.
Arguments:
""""""""""
The ``catchswitch`` operand must always be a token produced by a
:ref:`catchswitch <i_catchswitch>` instruction in a predecessor block. This
ensures that each ``catchpad`` has exactly one predecessor block, and it always
terminates in a ``catchswitch``.
The ``args`` correspond to whatever information the personality routine
requires to know if this is an appropriate handler for the exception. Control
will transfer to the ``catchpad`` if this is the first appropriate handler for
the exception.
The ``resultval`` has the type :ref:`token <t_token>` and is used to match the
``catchpad`` to corresponding :ref:`catchrets <i_catchret>` and other nested EH
pads.
Semantics:
""""""""""
When the call stack is being unwound due to an exception being thrown, the
exception is compared against the ``args``. If it doesn't match, control will
not reach the ``catchpad`` instruction. The representation of ``args`` is
entirely target and personality function-specific.
Like the :ref:`landingpad <i_landingpad>` instruction, the ``catchpad``
instruction must be the first non-phi of its parent basic block.
The meaning of the tokens produced and consumed by ``catchpad`` and other "pad"
instructions is described in the
`Windows exception handling documentation\ <ExceptionHandling.html#wineh>`_.
When a ``catchpad`` has been "entered" but not yet "exited" (as
described in the `EH documentation\ <ExceptionHandling.html#wineh-constraints>`_),
it is undefined behavior to execute a :ref:`call <i_call>` or :ref:`invoke <i_invoke>`
that does not carry an appropriate :ref:`"funclet" bundle <ob_funclet>`.
Example:
""""""""
.. code-block:: llvm
dispatch:
%cs = catchswitch within none [label %handler0] unwind to caller
;; A catch block which can catch an integer.
handler0:
%tok = catchpad within %cs [i8** @_ZTIi]
.. _i_catchret: .. _i_catchret:
'``catchret``' Instruction '``catchret``' Instruction
@ -8598,6 +8530,74 @@ Example:
catch i8** @_ZTIi catch i8** @_ZTIi
filter [1 x i8**] [@_ZTId] filter [1 x i8**] [@_ZTId]
.. _i_catchpad:
'``catchpad``' Instruction
^^^^^^^^^^^^^^^^^^^^^^^^^^
Syntax:
"""""""
::
<resultval> = catchpad within <catchswitch> [<args>*]
Overview:
"""""""""
The '``catchpad``' instruction is used by `LLVM's exception handling
system <ExceptionHandling.html#overview>`_ to specify that a basic block
begins a catch handler --- one where a personality routine attempts to transfer
control to catch an exception.
Arguments:
""""""""""
The ``catchswitch`` operand must always be a token produced by a
:ref:`catchswitch <i_catchswitch>` instruction in a predecessor block. This
ensures that each ``catchpad`` has exactly one predecessor block, and it always
terminates in a ``catchswitch``.
The ``args`` correspond to whatever information the personality routine
requires to know if this is an appropriate handler for the exception. Control
will transfer to the ``catchpad`` if this is the first appropriate handler for
the exception.
The ``resultval`` has the type :ref:`token <t_token>` and is used to match the
``catchpad`` to corresponding :ref:`catchrets <i_catchret>` and other nested EH
pads.
Semantics:
""""""""""
When the call stack is being unwound due to an exception being thrown, the
exception is compared against the ``args``. If it doesn't match, control will
not reach the ``catchpad`` instruction. The representation of ``args`` is
entirely target and personality function-specific.
Like the :ref:`landingpad <i_landingpad>` instruction, the ``catchpad``
instruction must be the first non-phi of its parent basic block.
The meaning of the tokens produced and consumed by ``catchpad`` and other "pad"
instructions is described in the
`Windows exception handling documentation\ <ExceptionHandling.html#wineh>`_.
When a ``catchpad`` has been "entered" but not yet "exited" (as
described in the `EH documentation\ <ExceptionHandling.html#wineh-constraints>`_),
it is undefined behavior to execute a :ref:`call <i_call>` or :ref:`invoke <i_invoke>`
that does not carry an appropriate :ref:`"funclet" bundle <ob_funclet>`.
Example:
""""""""
.. code-block:: llvm
dispatch:
%cs = catchswitch within none [label %handler0] unwind to caller
;; A catch block which can catch an integer.
handler0:
%tok = catchpad within %cs [i8** @_ZTIi]
.. _i_cleanuppad: .. _i_cleanuppad:
'``cleanuppad``' Instruction '``cleanuppad``' Instruction