1 files changed, 11 insertions, 0 deletions
diff --git a/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUInstPrinter.cpp b/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUInstPrinter.cpp
index d3b5718..3563caa 100644
--- a/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUInstPrinter.cpp
+++ b/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUInstPrinter.cpp
@@ -1280,6 +1280,17 @@ void AMDGPUInstPrinter::printPackedModifier(const MCInst *MI,
         (ModIdx != -1) ? MI->getOperand(ModIdx).getImm() : DefaultValue;
   }
 
+  // Some instructions, e.g. v_interp_p2_f16 in GFX9, have src0, src2, but no
+  // src1.
+  if (NumOps == 1 && AMDGPU::hasNamedOperand(Opc, AMDGPU::OpName::src2) &&
+      !AMDGPU::hasNamedOperand(Opc, AMDGPU::OpName::src1)) {
+    Ops[NumOps++] = DefaultValue; // Set src1_modifiers to default.
+    int Mod2Idx =
+        AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src2_modifiers);
+    assert(Mod2Idx != -1);
+    Ops[NumOps++] = MI->getOperand(Mod2Idx).getImm();
+  }
+
   const bool HasDst =
       (AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::vdst) != -1) ||
       (AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::sdst) != -1);