Fold conditional branches on constants away.

llvm-svn: 19360
2005-01-07 22:49:57 +00:00 · 2005-01-07 22:49:57 +00:00 · 5c66e45b92
parent cda3efa6e5
commit 5c66e45b92
1 changed files with 6 additions and 0 deletions
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@ -727,6 +727,12 @@ SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT,
    }

    break;
+  case ISD::BRCOND:
+    if (N2C)
+      if (N2C->getValue()) // Unconditional branch
+        return getNode(ISD::BR, MVT::Other, N1, N3);
+      else
+        return N1;         // Never-taken branch
  }

  SDNode *N = new SDNode(Opcode, N1, N2, N3);