[llvm-commits] [llvm] r49466 - /llvm/trunk/lib/Target/X86/README-SSE.txt

[Chris Lattner]

Author: lattner
Date: Thu Apr 10 00:54:50 2008
New Revision: 49466

URL: http://llvm.org/viewvc/llvm-project?rev=49466&view=rev
Log:
add a note, this is actually not too bad to implement.

Modified:
    llvm/trunk/lib/Target/X86/README-SSE.txt

Modified: llvm/trunk/lib/Target/X86/README-SSE.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/README-SSE.txt?rev=49466&r1=49465&r2=49466&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/README-SSE.txt (original)
+++ llvm/trunk/lib/Target/X86/README-SSE.txt Thu Apr 10 00:54:50 2008
@@ -472,7 +472,13 @@
 	addl	$12, %esp
 	ret
 
-instead of movsd from the stack.
+instead of movsd from the stack.  This is actually not too bad to implement. The
+best way to do this is to implement a dag combine that turns 
+bitconvert(build_pair(load a, load b)) into one load of the right type.  The
+only trick to this is writing the predicate that determines that a/b are at the
+right offset from each other.  For the enterprising hacker, InferAlignment is a
+helpful place to start poking if interested.
+
 
 //===---------------------------------------------------------------------===//