[PATCH] D140381: [PowerPC] Use Power9 test data class instruction to lower IS_FPCLASS

[Serge Pavlov via Phabricator via llvm-commits]

sepavloff added inline comments.


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Comment at: llvm/lib/Target/PowerPC/PPCISelLowering.cpp:10958
 
+static SDValue getDataClassTest(SDValue Op, unsigned Mask, const SDLoc &Dl,
+                                SelectionDAG &DAG,
----------------
It is better to use `FPClassTest` instead of `unsigned`. 


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Comment at: llvm/lib/Target/PowerPC/PPCISelLowering.cpp:10988
+    SDValue Rev =
+        getDataClassTest(Op, (~Mask) & fcAllFlags, Dl, DAG, Subtarget);
+    return DAG.getNOT(Dl, Rev, MVT::i1);
----------------
If `Mask` were `FPClassTest`, `& fcAllFlags` could be omitted.


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Comment at: llvm/lib/Target/PowerPC/PPCISelLowering.cpp:10995
+  if ((Mask & fcNormal) != 0) {
+    SDValue Rest = getDataClassTest(Op, Mask & (fcAllFlags ^ fcNormal), Dl, DAG,
+                                    Subtarget);
----------------
Should it be `Mask & ~fcNormal`? 


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Comment at: llvm/lib/Target/PowerPC/PPCISelLowering.cpp:11065
+  unsigned NativeMask = 0;
+  if (Mask & fcNan)
+    NativeMask |= DC_NAN;
----------------
Should it be `(Mask & fcNan) == fcNan)`?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D140381/new/

https://reviews.llvm.org/D140381