[Hexagon] Return 0 from getDotNewPredOp when .new opcode does not exist

This allows using this function to test if an instruction can be converted
to a .new form.

llvm-svn: 304549

2 files changed, 45 insertions, 3 deletions

diff --git a/llvm/lib/Target/Hexagon/HexagonInstrInfo.cpp b/llvm/lib/Target/Hexagon/HexagonInstrInfo.cpp
index 0fef91ec4d3..b76da727237 100644
--- a/llvm/lib/Target/Hexagon/HexagonInstrInfo.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonInstrInfo.cpp
@@ -3419,9 +3419,7 @@ int HexagonInstrInfo::getDotNewPredOp(const MachineInstr &MI,
   int NewOpcode = Hexagon::getPredNewOpcode(MI.getOpcode());
   if (NewOpcode >= 0)
     return NewOpcode;
-
-  dbgs() << "Cannot convert to .new: " << getName(MI.getOpcode()) << '\n';
-  llvm_unreachable(nullptr);
+  return 0;
 }
 
 int HexagonInstrInfo::getDotOldOp(const MachineInstr &MI) const {
diff --git a/llvm/test/CodeGen/Hexagon/newify-crash.ll b/llvm/test/CodeGen/Hexagon/newify-crash.ll
new file mode 100644
index 00000000000..705170b13a5
--- /dev/null
+++ b/llvm/test/CodeGen/Hexagon/newify-crash.ll
@@ -0,0 +1,44 @@
+; RUN: llc -march=hexagon < %s | FileCheck %s
+;
+; Check that this testcase doesn't crash.
+; CHECK: vadd
+
+target triple = "hexagon"
+
+define void @fred() #0 {
+b0:
+  br label %b1
+
+b1:                                               ; preds = %b7, %b0
+  %v2 = phi i32 [ 0, %b0 ], [ %v16, %b7 ]
+  %v3 = phi <32 x i32> [ undef, %b0 ], [ %v15, %b7 ]
+  %v4 = icmp slt i32 %v2, undef
+  br i1 %v4, label %b5, label %b7
+
+b5:                                               ; preds = %b1
+  %v6 = tail call <32 x i32> @llvm.hexagon.V6.vaddhsat.128B(<32 x i32> %v3, <32 x i32> undef)
+  br label %b7
+
+b7:                                               ; preds = %b5, %b1
+  %v8 = phi <32 x i32> [ %v6, %b5 ], [ %v3, %b1 ]
+  %v9 = tail call <32 x i32> @llvm.hexagon.V6.vaddhsat.128B(<32 x i32> %v8, <32 x i32> undef)
+  %v10 = tail call <32 x i32> @llvm.hexagon.V6.vaddhsat.128B(<32 x i32> %v9, <32 x i32> undef)
+  %v11 = tail call <32 x i32> @llvm.hexagon.V6.vaddhsat.128B(<32 x i32> %v10, <32 x i32> undef)
+  %v12 = tail call <32 x i32> @llvm.hexagon.V6.vaddhsat.128B(<32 x i32> %v11, <32 x i32> undef)
+  %v13 = tail call <32 x i32> @llvm.hexagon.V6.vaddhsat.128B(<32 x i32> %v12, <32 x i32> zeroinitializer)
+  %v14 = tail call <32 x i32> @llvm.hexagon.V6.vaddhsat.128B(<32 x i32> %v13, <32 x i32> undef)
+  %v15 = tail call <32 x i32> @llvm.hexagon.V6.vaddhsat.128B(<32 x i32> %v14, <32 x i32> undef)
+  %v16 = add nsw i32 %v2, 8
+  %v17 = icmp eq i32 %v16, 64
+  br i1 %v17, label %b18, label %b1
+
+b18:                                              ; preds = %b7
+  tail call void @f0() #0
+  ret void
+}
+
+declare <32 x i32> @llvm.hexagon.V6.vaddhsat.128B(<32 x i32>, <32 x i32>) #1
+declare void @f0() #0
+
+attributes #0 = { nounwind "target-cpu"="hexagonv60" "target-features"="+hvx,+hvx-double" }
+attributes #1 = { nounwind readnone }