(even better, get the book)
<http://www.mindview.net/Books/TICPP/ThinkingInCPP2e.html>`_.
-You are also encouraged to take a look at the :ref:`LLVM Coding Standards
-<coding_standards>` guide which focuses on how to write maintainable code more
+You are also encouraged to take a look at the :doc:`LLVM Coding Standards
+<CodingStandards>` guide which focuses on how to write maintainable code more
than where to put your curly braces.
.. _resources:
These five templates can be used with any classes, whether they have a v-table
or not. If you want to add support for these templates, see the document
-:ref:`How to set up LLVM-style RTTI for your class hierarchy
-<how-to-set-up-llvm-style-rtti>`
+:doc:`How to set up LLVM-style RTTI for your class hierarchy
+<HowToSetUpLLVMStyleRTTI>`
.. _string_apis:
SmallVector also provides a nice portable and efficient replacement for
``alloca``.
+.. note::
+
+ Prefer to use ``SmallVectorImpl<T>`` as a parameter type.
+
+ In APIs that don't care about the "small size" (most?), prefer to use
+ the ``SmallVectorImpl<T>`` class, which is basically just the "vector
+ header" (and methods) without the elements allocated after it. Note that
+ ``SmallVector<T, N>`` inherits from ``SmallVectorImpl<T>`` so the
+ conversion is implicit and costs nothing. E.g.
+
+ .. code-block:: c++
+
+ // BAD: Clients cannot pass e.g. SmallVector<Foo, 4>.
+ hardcodedSmallSize(SmallVector<Foo, 2> &Out);
+ // GOOD: Clients can pass any SmallVector<Foo, N>.
+ allowsAnySmallSize(SmallVectorImpl<Foo> &Out);
+
+ void someFunc() {
+ SmallVector<Foo, 8> Vec;
+ hardcodedSmallSize(Vec); // Error.
+ allowsAnySmallSize(Vec); // Works.
+ }
+
+ Even though it has "``Impl``" in the name, this is so widely used that
+ it really isn't "private to the implementation" anymore. A name like
+ ``SmallVectorHeader`` would be more appropriate.
+
.. _dss_vector:
<vector>
This combination provides the several nice properties: the result data is
contiguous in memory (good for cache locality), has few allocations, is easy to
address (iterators in the final vector are just indices or pointers), and can be
-efficiently queried with a standard binary or radix search.
+efficiently queried with a standard binary search (e.g.
+``std::lower_bound``; if you want the whole range of elements comparing
+equal, use ``std::equal_range``).
.. _dss_smallset:
and fast iteration over small sets. It is not intended for building composite
data structures.
+.. _dss_sparsemultiset:
+
+llvm/ADT/SparseMultiSet.h
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+SparseMultiSet adds multiset behavior to SparseSet, while retaining SparseSet's
+desirable attributes. Like SparseSet, it typically uses a lot of memory, but
+provides operations that are almost as fast as a vector. Typical keys are
+physical registers, virtual registers, or numbered basic blocks.
+
+SparseMultiSet is useful for algorithms that need very fast
+clear/find/insert/erase of the entire collection, and iteration over sets of
+elements sharing a key. It is often a more efficient choice than using composite
+data structures (e.g. vector-of-vectors, map-of-vectors). It is not intended for
+building composite data structures.
+
.. _dss_FoldingSet:
llvm/ADT/FoldingSet.h
set and has the sum of constant factors from the set-like container and the
sequential container that it uses. Use it **only** if you need to iterate over
the elements in a deterministic order. SetVector is also expensive to delete
-elements out of (linear time), unless you use it's "pop_back" method, which is
+elements out of (linear time), unless you use its "pop_back" method, which is
faster.
``SetVector`` is an adapter class that defaults to using ``std::vector`` and a
Note that both of these calls must be made *in isolation*. That is to say that
no other LLVM API calls may be executing at any time during the execution of
-``llvm_start_multithreaded()`` or ``llvm_stop_multithreaded``. It's is the
+``llvm_start_multithreaded()`` or ``llvm_stop_multithreaded``. It is the
client's responsibility to enforce this isolation.
The return value of ``llvm_start_multithreaded()`` indicates the success or
A bit-encoding in the 2 LSBits (least significant bits) of the ``Use::Prev``
allows to find the start of the ``User`` object:
-* ``00`` –> binary digit 0
+* ``00`` --- binary digit 0
-* ``01`` –> binary digit 1
+* ``01`` --- binary digit 1
-* ``10`` –> stop and calculate (``s``)
+* ``10`` --- stop and calculate (``s``)
-* ``11`` –> full stop (``S``)
+* ``11`` --- full stop (``S``)
Given a ``Use*``, all we have to do is to walk till we get a stop and we either
have a ``User`` immediately behind or we have to walk to the next stop picking
The Core LLVM Class Hierarchy Reference
=======================================
-``#include "llvm/Type.h"``
+``#include "llvm/IR/Type.h"``
header source: `Type.h <http://llvm.org/doxygen/Type_8h-source.html>`_
The ``Module`` class
--------------------
-``#include "llvm/Module.h"``
+``#include "llvm/IR/Module.h"``
header source: `Module.h <http://llvm.org/doxygen/Module_8h-source.html>`_
The ``Value`` class
-------------------
-``#include "llvm/Value.h"``
+``#include "llvm/IR/Value.h"``
header source: `Value.h <http://llvm.org/doxygen/Value_8h-source.html>`_
The ``User`` class
------------------
-``#include "llvm/User.h"``
+``#include "llvm/IR/User.h"``
header source: `User.h <http://llvm.org/doxygen/User_8h-source.html>`_
The ``Instruction`` class
-------------------------
-``#include "llvm/Instruction.h"``
+``#include "llvm/IR/Instruction.h"``
header source: `Instruction.h
<http://llvm.org/doxygen/Instruction_8h-source.html>`_
The ``GlobalValue`` class
-------------------------
-``#include "llvm/GlobalValue.h"``
+``#include "llvm/IR/GlobalValue.h"``
header source: `GlobalValue.h
<http://llvm.org/doxygen/GlobalValue_8h-source.html>`_
The ``Function`` class
----------------------
-``#include "llvm/Function.h"``
+``#include "llvm/IR/Function.h"``
header source: `Function.h <http://llvm.org/doxygen/Function_8h-source.html>`_
The ``GlobalVariable`` class
----------------------------
-``#include "llvm/GlobalVariable.h"``
+``#include "llvm/IR/GlobalVariable.h"``
header source: `GlobalVariable.h
<http://llvm.org/doxygen/GlobalVariable_8h-source.html>`_
The ``BasicBlock`` class
------------------------
-``#include "llvm/BasicBlock.h"``
+``#include "llvm/IR/BasicBlock.h"``
header source: `BasicBlock.h
<http://llvm.org/doxygen/BasicBlock_8h-source.html>`_
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