AMDGPU: Cleanup fmin/fmax legacy function

Use a more specific subtarget check and combine hasOneUse checks

llvm-svn: 293726

4 files changed, 14 insertions, 13 deletions

diff --git a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
index e7f15bcb081..70eb3e1a82c 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
@@ -972,14 +972,11 @@ SDValue AMDGPUTargetLowering::LowerINTRINSIC_WO_CHAIN(SDValue Op,
 }
 
 /// \brief Generate Min/Max node
-SDValue AMDGPUTargetLowering::CombineFMinMaxLegacy(const SDLoc &DL, EVT VT,
+SDValue AMDGPUTargetLowering::combineFMinMaxLegacy(const SDLoc &DL, EVT VT,
                                                    SDValue LHS, SDValue RHS,
                                                    SDValue True, SDValue False,
                                                    SDValue CC,
                                                    DAGCombinerInfo &DCI) const {
-  if (Subtarget->getGeneration() >= AMDGPUSubtarget::VOLCANIC_ISLANDS)
-    return SDValue();
-
   if (!(LHS == True && RHS == False) && !(LHS == False && RHS == True))
     return SDValue();
 
@@ -2830,14 +2827,14 @@ SDValue AMDGPUTargetLowering::performSelectCombine(SDNode *N,
       SDValue NewCond = DAG.getSetCC(SL, Cond.getValueType(), LHS, RHS, NewCC);
       return DAG.getNode(ISD::SELECT, SL, VT, NewCond, False, True);
     }
-  }
 
-  if (VT == MVT::f32 && Cond.hasOneUse()) {
-    SDValue MinMax
-      = CombineFMinMaxLegacy(SDLoc(N), VT, LHS, RHS, True, False, CC, DCI);
-    // Revisit this node so we can catch min3/max3/med3 patterns.
-    //DCI.AddToWorklist(MinMax.getNode());
-    return MinMax;
+    if (VT == MVT::f32 && Subtarget->hasFminFmaxLegacy()) {
+      SDValue MinMax
+        = combineFMinMaxLegacy(SDLoc(N), VT, LHS, RHS, True, False, CC, DCI);
+      // Revisit this node so we can catch min3/max3/med3 patterns.
+      //DCI.AddToWorklist(MinMax.getNode());
+      return MinMax;
+    }
   }
 
   // There's no reason to not do this if the condition has other uses.
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h
index f323c786e1d..880d571078b 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h
+++ b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h
@@ -174,7 +174,7 @@ public:
                           SmallVectorImpl<SDValue> &Results,
                           SelectionDAG &DAG) const override;
 
-  SDValue CombineFMinMaxLegacy(const SDLoc &DL, EVT VT, SDValue LHS,
+  SDValue combineFMinMaxLegacy(const SDLoc &DL, EVT VT, SDValue LHS,
                                SDValue RHS, SDValue True, SDValue False,
                                SDValue CC, DAGCombinerInfo &DCI) const;
 
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUSubtarget.h b/llvm/lib/Target/AMDGPU/AMDGPUSubtarget.h
index 485f6f29de4..f66ebd6afc2 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUSubtarget.h
+++ b/llvm/lib/Target/AMDGPU/AMDGPUSubtarget.h
@@ -329,6 +329,10 @@ public:
     return isAmdHsaOS() || isMesaKernel(MF);
   }
 
+  bool hasFminFmaxLegacy() const {
+    return getGeneration() < AMDGPUSubtarget::VOLCANIC_ISLANDS;
+  }
+
   /// \brief Returns the offset in bytes from the start of the input buffer
   ///        of the first explicit kernel argument.
   unsigned getExplicitKernelArgOffset(const MachineFunction &MF) const {
diff --git a/llvm/lib/Target/AMDGPU/R600ISelLowering.cpp b/llvm/lib/Target/AMDGPU/R600ISelLowering.cpp
index c31af80258f..812555060b2 100644
--- a/llvm/lib/Target/AMDGPU/R600ISelLowering.cpp
+++ b/llvm/lib/Target/AMDGPU/R600ISelLowering.cpp
@@ -916,7 +916,7 @@ SDValue R600TargetLowering::LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const
 
   if (VT == MVT::f32) {
     DAGCombinerInfo DCI(DAG, AfterLegalizeVectorOps, true, nullptr);
-    SDValue MinMax = CombineFMinMaxLegacy(DL, VT, LHS, RHS, True, False, CC, DCI);
+    SDValue MinMax = combineFMinMaxLegacy(DL, VT, LHS, RHS, True, False, CC, DCI);
     if (MinMax)
       return MinMax;
   }