[Mesa-dev] [PATCH] radeon/llvm: replaces fragment input with negative index with undef values

[Vincent Lejeune]

---
 lib/Target/AMDGPU/R600ISelLowering.cpp | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/lib/Target/AMDGPU/R600ISelLowering.cpp b/lib/Target/AMDGPU/R600ISelLowering.cpp
index c837705..c6d9c4a 100644
--- a/lib/Target/AMDGPU/R600ISelLowering.cpp
+++ b/lib/Target/AMDGPU/R600ISelLowering.cpp
@@ -450,7 +450,9 @@ SDValue R600TargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const
       return CreateLiveInRegister(DAG, &AMDGPU::R600_TReg32RegClass, Reg, VT);
     }
     case AMDGPUIntrinsic::R600_load_input_perspective: {
-      unsigned slot = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
+      int slot = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
+      if (slot < 0)
+        return DAG.getUNDEF(MVT::f32);
       SDValue FullVector = DAG.getNode(
           AMDGPUISD::INTERP,
           DL, MVT::v4f32,
@@ -459,7 +461,9 @@ SDValue R600TargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const
         DL, VT, FullVector, DAG.getConstant(slot % 4, MVT::i32));
     }
     case AMDGPUIntrinsic::R600_load_input_linear: {
-      unsigned slot = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
+      int slot = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
+      if (slot < 0)
+        return DAG.getUNDEF(MVT::f32);
       SDValue FullVector = DAG.getNode(
         AMDGPUISD::INTERP,
         DL, MVT::v4f32,
@@ -468,7 +472,9 @@ SDValue R600TargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const
         DL, VT, FullVector, DAG.getConstant(slot % 4, MVT::i32));
     }
     case AMDGPUIntrinsic::R600_load_input_constant: {
-      unsigned slot = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
+      int slot = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
+      if (slot < 0)
+        return DAG.getUNDEF(MVT::f32);
       SDValue FullVector = DAG.getNode(
         AMDGPUISD::INTERP_P0,
         DL, MVT::v4f32,
-- 
1.7.11.7