Added Sphinx documentation generation to CMake build system.

[oota-llvm.git] / docs / LangRef.rst

diff --git a/docs/LangRef.rst b/docs/LangRef.rst
index d18d4ebac9089936335c384fa9ce1b185bbb4952..752e3578222d546a41ce9e3f3c96831b014bd363 100644 (file)
--- a/docs/LangRef.rst
+++ b/docs/LangRef.rst
@@ -681,6 +681,10 @@ the aliasee.
 
 The aliasee must be a definition.
 
 
 The aliasee must be a definition.
 

+Aliases are not allowed to point to aliases with linkages that can be
+overridden. Since they are only a second name, the possibility of the
+intermediate alias being overridden cannot be represented in an object file.
+

 .. _namedmetadatastructure:
 
 Named Metadata
 .. _namedmetadatastructure:
 
 Named Metadata


@@ -765,8 +769,6 @@ Currently, only the following parameter attributes are defined:
 
 ``inalloca``
 
 
 ``inalloca``
 

-.. Warning:: This feature is unstable and not fully implemented.
-

     The ``inalloca`` argument attribute allows the caller to take the
     address of outgoing stack arguments.  An ``inalloca`` argument must
     be a pointer to stack memory produced by an ``alloca`` instruction.
     The ``inalloca`` argument attribute allows the caller to take the
     address of outgoing stack arguments.  An ``inalloca`` argument must
     be a pointer to stack memory produced by an ``alloca`` instruction.


@@ -800,6 +802,9 @@ Currently, only the following parameter attributes are defined:
     not to trap and to be properly aligned. This may only be applied to
     the first parameter. This is not a valid attribute for return
     values.
     not to trap and to be properly aligned. This may only be applied to
     the first parameter. This is not a valid attribute for return
     values.

+
+.. _noalias:
+

 ``noalias``
     This indicates that pointer values :ref:`based <pointeraliasing>` on
     the argument or return value do not alias pointer values which are
 ``noalias``
     This indicates that pointer values :ref:`based <pointeraliasing>` on
     the argument or return value do not alias pointer values which are


@@ -809,8 +814,8 @@ Currently, only the following parameter attributes are defined:
     "irrelevant" to the ``noalias`` keyword for the arguments and return
     value used in that call. The caller shares the responsibility with
     the callee for ensuring that these requirements are met. For further
     "irrelevant" to the ``noalias`` keyword for the arguments and return
     value used in that call. The caller shares the responsibility with
     the callee for ensuring that these requirements are met. For further

-    details, please see the discussion of the NoAlias response in `alias
-    analysis <AliasAnalysis.html#MustMayNo>`_.
+    details, please see the discussion of the NoAlias response in :ref:`alias
+    analysis <Must, May, or No>`.

 
     Note that this definition of ``noalias`` is intentionally similar
     to the definition of ``restrict`` in C99 for function arguments,
 
     Note that this definition of ``noalias`` is intentionally similar
     to the definition of ``restrict`` in C99 for function arguments,


@@ -1984,6 +1989,8 @@ notion of a forward declared structure.
 | ``opaque``   | An opaque type.   |
 +--------------+-------------------+
 
 | ``opaque``   | An opaque type.   |
 +--------------+-------------------+
 

+.. _constants:
+

 Constants
 =========
 
 Constants
 =========
 


@@ -6116,7 +6123,7 @@ Overview:
 """""""""
 
 The '``select``' instruction is used to choose one value based on a
 """""""""
 
 The '``select``' instruction is used to choose one value based on a

-condition, without branching.
+condition, without IR-level branching.

 
 Arguments:
 """"""""""
 
 Arguments:
 """"""""""


@@ -6952,22 +6959,25 @@ Syntax:
 Overview:
 """""""""
 
 Overview:
 """""""""
 

-The '``llvm.clear_cache``' intrinsic provides access to the systemcall
-that flushes the cache at the range specified. Some targets need this
-to specifically flush the instruction cache when executable data changes
-in memory (self-modifying code). Other targets have unified intruction
-and data cache, so they don't need any calls.
+The '``llvm.clear_cache``' intrinsic ensures visibility of modifications
+in the specified range to the execution unit of the processor. On
+targets with non-unified instruction and data cache, the implementation
+flushes the instruction cache.

 
 Semantics:
 """"""""""
 
 
 Semantics:
 """"""""""
 

-When directly supported, this intrinsic will either return a call to
-the appropriate cache clearing system call (usually ``__clear_cache``)
-when the caches are not unified (ARM, Mips) or just remove the call
-altogether when they are (ex. x86_64).
+On platforms with coherent instruction and data caches (e.g. x86), this
+intrinsic is a nop. On platforms with non-coherent instruction and data
+cache (e.g. ARM, MIPS), the intrinsic is lowered either to appropriate
+instructions or a system call, if cache flushing requires special
+privileges.
+
+The default behavior is to emit a call to ``__clear_cache`` from the run
+time library.

 
 

-Targets must implement it directly to have either behaviour, as the
-default is to bail with "Not Implemented" message.
+This instrinsic does *not* empty the instruction pipeline. Modifications
+of the current function are outside the scope of the intrinsic.

 
 Standard C Library Intrinsics
 -----------------------------
 
 Standard C Library Intrinsics
 -----------------------------