[PATCH] D46957: [x86] Lower some trunc + shuffle patterns to vpmov[q|d][b|w]

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.


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Comment at: lib/Target/X86/X86ISelLowering.cpp:9414
+
+  if (SwappedOps) {
+    // Look for e.g.: <8, 10, 12, 14, 0, 0, 0, 0>
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Instead of repeating for SwappedOps - can't you just use start/end values? Else take a local copy of the shuffle mask and use ShuffleVectorSDNode::commuteMask?


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Comment at: lib/Target/X86/X86ISelLowering.cpp:9418
+    // These should refer to the second vectors elements
+    while (I < N) {
+      if (Mask[I] != Size + I * delta)
----------------
Can you use the shuffle mask helpers for any/all of these - isUndefOrInRange etc?


https://reviews.llvm.org/D46957