[WinEH] Move WinEHFuncInfo from MachineModuleInfo to MachineFunction

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

diff --git a/docs/LangRef.rst b/docs/LangRef.rst
index 507c3bfd334e6f003ed16ba560ef21e772a1281a..b1a92dc0ebde442a14d3104467faaecace415e35 100644 (file)
--- a/docs/LangRef.rst
+++ b/docs/LangRef.rst
@@ -1277,6 +1277,10 @@ example:
     This function attribute indicates that the function never returns
     normally. This produces undefined behavior at runtime if the
     function ever does dynamically return.
+``norecurse``
+    This function attribute indicates that the function does not call itself
+    either directly or indirectly down any possible call path. This produces
+    undefined behavior at runtime if the function ever does recurse.
 ``nounwind``
     This function attribute indicates that the function never raises an
     exception. If the function does raise an exception, its runtime
@@ -1484,6 +1488,27 @@ operand bundle to not miscompile programs containing it.
   of the called function.  Inter-procedural optimizations work as
   usual as long as they take into account the first two properties.
 
+More specific types of operand bundles are described below.
+
+Deoptimization Operand Bundles
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Deoptimization operand bundles are characterized by the ``"deopt``
+operand bundle tag.  These operand bundles represent an alternate
+"safe" continuation for the call site they're attached to, and can be
+used by a suitable runtime to deoptimize the compiled frame at the
+specified call site.  Exact details of deoptimization is out of scope
+for the language reference, but it usually involves rewriting a
+compiled frame into a set of interpreted frames.
+
+From the compiler's perspective, deoptimization operand bundles make
+the call sites they're attached to at least ``readonly``.  They read
+through all of their pointer typed operands (even if they're not
+otherwise escaped) and the entire visible heap.  Deoptimization
+operand bundles do not capture their operands except during
+deoptimization, in which case control will not be returned to the
+compiled frame.
+
 .. _moduleasm:
 
 Module-Level Inline Assembly
@@ -2409,6 +2434,9 @@ Simple Constants
 **Null pointer constants**
     The identifier '``null``' is recognized as a null pointer constant
     and must be of :ref:`pointer type <t_pointer>`.
+**Token constants**
+    The identifier '``none``' is recognized as an empty token constant
+    and must be of :ref:`token type <t_token>`.
 
 The one non-intuitive notation for constants is the hexadecimal form of
 floating point constants. For example, the form
@@ -8382,7 +8410,7 @@ Syntax:
 
 ::
 
-      <result> = [tail | musttail] call [cconv] [ret attrs] <ty> [<fnty>*] <fnptrval>(<function args>) [fn attrs]
+      <result> = [tail | musttail | notail ] call [cconv] [ret attrs] <ty> [<fnty>*] <fnptrval>(<function args>) [fn attrs]
                    [ operand bundles ]
 
 Overview:
@@ -8435,6 +8463,10 @@ This instruction requires several arguments:
    -  `Platform-specific constraints are
       met. <CodeGenerator.html#tailcallopt>`_
 
+#. The optional ``notail`` marker indicates that the optimizers should not add
+   ``tail`` or ``musttail`` markers to the call. It is used to prevent tail
+   call optimization from being performed on the call.
+
 #. The optional "cconv" marker indicates which :ref:`calling
    convention <callingconv>` the call should use. If none is
    specified, the call defaults to using C calling conventions. The
@@ -10385,6 +10417,34 @@ Bit Manipulation Intrinsics
 LLVM provides intrinsics for a few important bit manipulation
 operations. These allow efficient code generation for some algorithms.
 
+'``llvm.bitreverse.*``' Intrinsics
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Syntax:
+"""""""
+
+This is an overloaded intrinsic function. You can use bitreverse on any
+integer type.
+
+::
+
+      declare i16 @llvm.bitreverse.i16(i16 <id>)
+      declare i32 @llvm.bitreverse.i32(i32 <id>)
+      declare i64 @llvm.bitreverse.i64(i64 <id>)
+
+Overview:
+"""""""""
+
+The '``llvm.bitreverse``' family of intrinsics is used to reverse the
+bitpattern of an integer value; for example ``0b1234567`` becomes
+``0b7654321``.
+
+Semantics:
+""""""""""
+
+The ``llvm.bitreverse.iN`` intrinsic returns an i16 value that has bit
+``M`` in the input moved to bit ``N-M`` in the output.
+
 '``llvm.bswap.*``' Intrinsics
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^