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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27360 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/PowerPC/README.txt b/lib/Target/PowerPC/README.txt
index 14a0bc124ed7f42bfa1374f323615426675535ef..e29dd52e282d32146ec2c88a19cd47ac11a78488 100644 (file)
--- a/lib/Target/PowerPC/README.txt
+++ b/lib/Target/PowerPC/README.txt
@@ -551,3 +551,12 @@ void func(unsigned int *ret, float dx, float dy, float dz, float dw) {
 
 ===-------------------------------------------------------------------------===
 
+extract_vector_elt of an arbitrary constant vector can be done with the 
+following instructions:
+
+vTemp = vec_splat(v0,2);    // 2 is the element the src is in.
+vec_ste(&destloc,0,vTemp);
+
+We can do an arbitrary non-constant value by using lvsr/perm/ste.
+
+===-------------------------------------------------------------------------===