[llvm-commits] [llvm] r45662 - /llvm/trunk/docs/LangRef.html

Chris Lattner sabre at nondot.org
Sun Jan 6 13:04:44 PST 2008


Author: lattner
Date: Sun Jan  6 15:04:43 2008
New Revision: 45662

URL: http://llvm.org/viewvc/llvm-project?rev=45662&view=rev
Log:
improve description of alignment, patch by Alain Frisch.

Modified:
    llvm/trunk/docs/LangRef.html

Modified: llvm/trunk/docs/LangRef.html
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/docs/LangRef.html?rev=45662&r1=45661&r2=45662&view=diff

==============================================================================
--- llvm/trunk/docs/LangRef.html (original)
+++ llvm/trunk/docs/LangRef.html Sun Jan  6 15:04:43 2008
@@ -2843,6 +2843,16 @@
 the number or order of execution of this <tt>load</tt> with other
 volatile <tt>load</tt> and <tt><a href="#i_store">store</a></tt>
 instructions. </p>
+<p>
+The optional "align" argument specifies the alignment of the operation
+(that is, the alignment of the memory address). A value of 0 or an
+omitted "align" argument means that the operation has the preferential
+alignment for the target. It is the responsibility of the code emitter
+to ensure that the alignment information is correct. Overestimating
+the alignment results in an undefined behavior. Underestimating the
+alignment may produce less efficient code. An alignment of 1 is always
+safe.
+</p>
 <h5>Semantics:</h5>
 <p>The location of memory pointed to is loaded.</p>
 <h5>Examples:</h5>
@@ -2870,6 +2880,16 @@
 optimizer is not allowed to modify the number or order of execution of
 this <tt>store</tt> with other volatile <tt>load</tt> and <tt><a
  href="#i_store">store</a></tt> instructions.</p>
+<p>
+The optional "align" argument specifies the alignment of the operation
+(that is, the alignment of the memory address). A value of 0 or an
+omitted "align" argument means that the operation has the preferential
+alignment for the target. It is the responsibility of the code emitter
+to ensure that the alignment information is correct. Overestimating
+the alignment results in an undefined behavior. Underestimating the
+alignment may produce less efficient code. An alignment of 1 is always
+safe.
+</p>
 <h5>Semantics:</h5>
 <p>The contents of memory are updated to contain '<tt><value></tt>'
 at the location specified by the '<tt><pointer></tt>' operand.</p>





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