Document that the shuffle mask may contain undef

values.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47719 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Duncan Sands 2008-02-28 17:12:11 +00:00
parent 9fa4226925
commit 59c2e868ff

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@ -301,16 +301,16 @@ namespace ISD {
/// vector value) starting with the (potentially variable) element number
/// IDX, which must be a multiple of the result vector length.
EXTRACT_SUBVECTOR,
/// VECTOR_SHUFFLE(VEC1, VEC2, SHUFFLEVEC) - Returns a vector, of the same
/// type as VEC1/VEC2. SHUFFLEVEC is a BUILD_VECTOR of constant int values
/// (regardless of whether its datatype is legal or not) that indicate
/// which value each result element will get. The elements of VEC1/VEC2 are
/// enumerated in order. This is quite similar to the Altivec 'vperm'
/// instruction, except that the indices must be constants and are in terms
/// of the element size of VEC1/VEC2, not in terms of bytes.
/// (maybe of an illegal datatype) or undef that indicate which value each
/// result element will get. The elements of VEC1/VEC2 are enumerated in
/// order. This is quite similar to the Altivec 'vperm' instruction, except
/// that the indices must be constants and are in terms of the element size
/// of VEC1/VEC2, not in terms of bytes.
VECTOR_SHUFFLE,
/// SCALAR_TO_VECTOR(VAL) - This represents the operation of loading a
/// scalar value into element 0 of the resultant vector type. The top
/// elements 1 to N-1 of the N-element vector are undefined.