[PATCH] D26767: [AMDGPU] Promote f16/i16 conversions to f32/i32 + custom lower f16 = fp_round f64

[Matt Arsenault via llvm-commits]

arsenm added inline comments.


================
Comment at: lib/Target/AMDGPU/SIISelLowering.cpp:3664-3668
+  case ISD::BITCAST: {
+    if (N->getValueType(0) == N->getOperand(0).getValueType())
+      return N->getOperand(0);
+    break;
+  }
----------------
kzhuravl wrote:
> arsenm wrote:
> > kzhuravl wrote:
> > > arsenm wrote:
> > > > This should be very unnecessary
> > > I am getting a "cannot select: i16 = bitcast i16". Do you have a suggestion on how to solve it?
> > > 
> > > Thanks
> > Where is that coming from? I thought getNode folded out trivial bitcasts like this already
> It is coming right after:
> https://github.com/llvm-mirror/llvm/blob/master/lib/Target/AMDGPU/AMDGPUISelLowering.cpp#L2100
> 
> in the optimized dag phase
I don't see how that would create a bitcast, or create one that somehow bypasses the no-op fold


https://reviews.llvm.org/D26767