From: Evan Cheng <evan.cheng@apple.com>
Date: Thu, 13 Apr 2006 05:09:45 +0000 (+0000)
Subject: Update
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=fc7c17abb511b0a61ccc67ff4c2c159c2b882fa9;p=oota-llvm.git

Update


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27643 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt
index 08dcf5afc42..f58991728ea 100644
--- a/lib/Target/X86/README.txt
+++ b/lib/Target/X86/README.txt
@@ -191,6 +191,18 @@ commutative, it is not matched with the load on both sides.  The dag combiner
 should be made smart enough to cannonicalize the load into the RHS of a compare
 when it can invert the result of the compare for free.
 
+How about intrinsics? An example is:
+  *res = _mm_mulhi_epu16(*A, _mm_mul_epu32(*B, *C));
+
+compiles to
+	pmuludq (%eax), %xmm0
+	movl 8(%esp), %eax
+	movdqa (%eax), %xmm1
+	pmulhuw %xmm0, %xmm1
+
+The transformation probably requires a X86 specific pass or a DAG combiner
+target specific hook.
+
 //===---------------------------------------------------------------------===//
 
 LSR should be turned on for the X86 backend and tuned to take advantage of its