[llvm] 836c7dc - DAG: Fix getNode dropping flags if there's a glue output

[Matt Arsenault via llvm-commits]

Author: Matt Arsenault
Date: 2020-06-01T13:48:02-04:00
New Revision: 836c7dcf1238683ff18882affac1dae5ae5c5f79

URL: https://github.com/llvm/llvm-project/commit/836c7dcf1238683ff18882affac1dae5ae5c5f79
DIFF: https://github.com/llvm/llvm-project/commit/836c7dcf1238683ff18882affac1dae5ae5c5f79.diff

LOG: DAG: Fix getNode dropping flags if there's a glue output

The AMDGPU non-strict fdiv lowering needs to introduce an FP mode
switch in some cases, and has custom nodes to provide chain/glue for
the intermediate FP operations. We need to propagate nofpexcept here,
but getNode was dropping the flags.

Adding nofpexcept in the AMDGPU custom lowering is left to a future
patch.

Also fix a second case where flags were dropped, but in this case it
seems it just didn't handle this number of operands.

Test will be included in future AMDGPU patch.

Added: 
    

Modified: 
    llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 232b1ea6bb78..7e1991c866eb 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -7444,6 +7444,7 @@ SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
     createOperands(N, Ops);
   }
 
+  N->setFlags(Flags);
   InsertNode(N);
   SDValue V(N, 0);
   NewSDValueDbgMsg(V, "Creating new node: ", this);
@@ -7525,13 +7526,14 @@ SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList,
       return SDValue(E, 0);
 
     N = newSDNode<SDNode>(Opcode, DL.getIROrder(), DL.getDebugLoc(), VTList);
-    N->setFlags(Flags);
     createOperands(N, Ops);
     CSEMap.InsertNode(N, IP);
   } else {
     N = newSDNode<SDNode>(Opcode, DL.getIROrder(), DL.getDebugLoc(), VTList);
     createOperands(N, Ops);
   }
+
+  N->setFlags(Flags);
   InsertNode(N);
   SDValue V(N, 0);
   NewSDValueDbgMsg(V, "Creating new node: ", this);