summaryrefslogtreecommitdiffstats
path: root/llvm/docs/LangRef.html
diff options
context:
space:
mode:
authorDan Gohman <gohman@apple.com>2010-07-06 15:26:33 +0000
committerDan Gohman <gohman@apple.com>2010-07-06 15:26:33 +0000
commit6c858db40cfe6bcb0d79eeadd467db44dc6b71d0 (patch)
tree22fa52298bcfb4720381769e409579ee2c7b5dfe /llvm/docs/LangRef.html
parente4152304770369471414c8b9b5beb5df741e2254 (diff)
downloadbcm5719-llvm-6c858db40cfe6bcb0d79eeadd467db44dc6b71d0.tar.gz
bcm5719-llvm-6c858db40cfe6bcb0d79eeadd467db44dc6b71d0.zip
Note the relationship between C99 restrict and LLVM noalias, and
clarify a few other things. llvm-svn: 107659
Diffstat (limited to 'llvm/docs/LangRef.html')
-rw-r--r--llvm/docs/LangRef.html13
1 files changed, 11 insertions, 2 deletions
diff --git a/llvm/docs/LangRef.html b/llvm/docs/LangRef.html
index ad730deffb8..f8a2643803c 100644
--- a/llvm/docs/LangRef.html
+++ b/llvm/docs/LangRef.html
@@ -1062,7 +1062,15 @@ declare signext i8 @returns_signed_char()
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
- <a href="AliasAnalysis.html#MustMayNo">alias analysis</a>.</dd>
+ <a href="AliasAnalysis.html#MustMayNo">alias analysis</a>.<br>
+<br>
+ Note that this definition of <tt>noalias<tt> is intentionally
+ similar to the definition of <tt>restrict<tt> in C99 for function
+ arguments, thought it is slightly weaker.
+<br>
+ For function return values, C99's <tt>restrict</tt> is not meaningful,
+ while LLVM's <tt>noalias</tt> is.
+ </dd>
<dt><tt><b><a name="nocapture">nocapture</a></b></tt></dt>
<dd>This indicates that the callee does not make any copies of the pointer
@@ -2397,7 +2405,8 @@ has undefined behavior.</p>
<li>An instruction with externally visible side effects depends on the most
recent preceding instruction with externally visible side effects, following
- the order in the IR. (This includes volatile loads and stores.)</li>
+ the order in the IR. (This includes
+ <a href="#volatile">volatile operations</a>.)</li>
<li>An instruction <i>control-depends</i> on a
<a href="#terminators">terminator instruction</a>
OpenPOWER on IntegriCloud