From: Chris Lattner <sabre@nondot.org>
Date: Sat, 14 Apr 2007 23:06:09 +0000 (+0000)
Subject: add a note
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=7c162645ae4c33474df6e2b25412387ed94e421b;p=oota-llvm.git

add a note


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36028 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt
index 7c274280605..0ed1e30f768 100644
--- a/lib/Target/X86/README.txt
+++ b/lib/Target/X86/README.txt
@@ -1049,3 +1049,21 @@ int decode_byte (const decode_t* decode) {
 
 //===---------------------------------------------------------------------===//
 
+This:
+#include <xmmintrin.h>
+unsigned test(float f) {
+ return _mm_cvtsi128_si32( (__m128i) _mm_set_ss( f ));
+}
+
+Compiles to:
+_test:
+        movss 4(%esp), %xmm0
+        movd %xmm0, %eax
+        ret
+
+it should compile to a move from the stack slot directly into eax.  DAGCombine
+has this xform, but it is currently disabled until the alignment fields of 
+the load/store nodes are trustworthy.
+
+
+