PR2957

ISD::VECTOR_SHUFFLE now stores an array of integers representing the shuffle
mask internal to the node, rather than taking a BUILD_VECTOR of ConstantSDNodes
as the shuffle mask.  A value of -1 represents UNDEF.

In addition to eliminating the creation of illegal BUILD_VECTORS just to 
represent shuffle masks, we are better about canonicalizing the shuffle mask,
resulting in substantially better code for some classes of shuffles.

A clean up of x86 shuffle code, and some canonicalizing in DAGCombiner is next.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69952 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCISelLowering.h b/lib/Target/PowerPC/PPCISelLowering.h
index 01111cf..7946474 100644
--- a/lib/Target/PowerPC/PPCISelLowering.h
+++ b/lib/Target/PowerPC/PPCISelLowering.h
@@ -175,19 +175,21 @@
   namespace PPC {
     /// isVPKUHUMShuffleMask - Return true if this is the shuffle mask for a
     /// VPKUHUM instruction.
-    bool isVPKUHUMShuffleMask(SDNode *N, bool isUnary);
+    bool isVPKUHUMShuffleMask(ShuffleVectorSDNode *N, bool isUnary);
     
     /// isVPKUWUMShuffleMask - Return true if this is the shuffle mask for a
     /// VPKUWUM instruction.
-    bool isVPKUWUMShuffleMask(SDNode *N, bool isUnary);
+    bool isVPKUWUMShuffleMask(ShuffleVectorSDNode *N, bool isUnary);
 
     /// isVMRGLShuffleMask - Return true if this is a shuffle mask suitable for
     /// a VRGL* instruction with the specified unit size (1,2 or 4 bytes).
-    bool isVMRGLShuffleMask(SDNode *N, unsigned UnitSize, bool isUnary);
+    bool isVMRGLShuffleMask(ShuffleVectorSDNode *N, unsigned UnitSize,
+                            bool isUnary);
 
     /// isVMRGHShuffleMask - Return true if this is a shuffle mask suitable for
     /// a VRGH* instruction with the specified unit size (1,2 or 4 bytes).
-    bool isVMRGHShuffleMask(SDNode *N, unsigned UnitSize, bool isUnary);
+    bool isVMRGHShuffleMask(ShuffleVectorSDNode *N, unsigned UnitSize,
+                            bool isUnary);
     
     /// isVSLDOIShuffleMask - If this is a vsldoi shuffle mask, return the shift
     /// amount, otherwise return -1.
@@ -196,7 +198,7 @@
     /// isSplatShuffleMask - Return true if the specified VECTOR_SHUFFLE operand
     /// specifies a splat of a single element that is suitable for input to
     /// VSPLTB/VSPLTH/VSPLTW.
-    bool isSplatShuffleMask(SDNode *N, unsigned EltSize);
+    bool isSplatShuffleMask(ShuffleVectorSDNode *N, unsigned EltSize);
     
     /// isAllNegativeZeroVector - Returns true if all elements of build_vector
     /// are -0.0.