[PATCH] D78728: [ARM] Convert floating point splats to integer

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: llvm/lib/CodeGen/CodeGenPrepare.cpp:6436
 /// codegen can spot all lanes are identical.
-bool CodeGenPrepare::optimizeShuffleVectorInst(ShuffleVectorInst *SVI) {
+bool CodeGenPrepare::sinkShuffleVectorToShift(ShuffleVectorInst *SVI) {
   BasicBlock *DefBB = SVI->getParent();
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I guess this is only loosely related to your patch, but should this transform also be handled by tryToSinkFreeOperands?


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Comment at: llvm/lib/CodeGen/CodeGenPrepare.cpp:6525
+    if (auto *Op = dyn_cast<Instruction>(BCI->getOperand(0)))
+      if (BCI->getParent() != Op->getParent() && !isa<PHINode>(Op))
+        BCI->moveAfter(Op);
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Checking whether an insertion point is legal is more complicated than this.  In particular, you can't insert code after an invoke/callbr, and you can't insert code into a block terminated by a catchswitch.

I'm not sure if there's a helper for this check anywhere.


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Comment at: llvm/lib/Target/ARM/ARMISelLowering.cpp:15786
 
+Type *ARMTargetLowering::shouldConvertSplatType(Instruction *SVI) const {
+  if (!Subtarget->hasMVEIntegerOps())
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Is this specifically a ShuffleVectorInst?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D78728/new/

https://reviews.llvm.org/D78728