[PATCH] D24221: AVX512F: FMA intrinsic + FNEG - sequence optimization

[Sanjay Patel via llvm-commits]

spatel added inline comments.

================
Comment at: ../lib/Target/X86/X86ISelLowering.cpp:30307
@@ +30306,3 @@
+/// In this case we go though all bitcasts.
+bool isFNEG(SDNode *N, SDValue* Op0 = nullptr) {
+  if (N->getOpcode() == ISD::FNEG) {
----------------
This interface feels awkward. The normal pattern is:
static SDValue getFNeg(SDNode *N)

Ie, if there's no negated value, it will return the empty SDValue(), and the caller can use that as a bool value if it wants to.

================
Comment at: ../lib/Target/X86/X86ISelLowering.cpp:30359-30361
@@ +30358,5 @@
+  SDValue Arg;
+  bool IsFNEGNode = isFNEG(N, &Arg);
+  if (!IsFNEGNode)
+    llvm_unreachable("Expected FNEG node");
+ 
----------------
This question was missed?


Repository:
  rL LLVM

https://reviews.llvm.org/D24221