R600/SI: Combine min3/max3 instructions

[oota-llvm.git] / lib / Target / R600 / AMDGPUISelLowering.cpp

diff --git a/lib/Target/R600/AMDGPUISelLowering.cpp b/lib/Target/R600/AMDGPUISelLowering.cpp
index 5561bf8976c2352b99cdbb57b6184e5e3a53ac26..83083786fe8699aaac5fce6834ff8632b3227a48 100644 (file)
--- a/lib/Target/R600/AMDGPUISelLowering.cpp
+++ b/lib/Target/R600/AMDGPUISelLowering.cpp
@@ -378,6 +378,7 @@ AMDGPUTargetLowering::AMDGPUTargetLowering(TargetMachine &TM) :
   setOperationAction(ISD::FNEARBYINT, MVT::f64, Custom);
 
   setTargetDAGCombine(ISD::MUL);
+  setTargetDAGCombine(ISD::SELECT);
   setTargetDAGCombine(ISD::SELECT_CC);
   setTargetDAGCombine(ISD::STORE);
 
@@ -999,21 +1000,16 @@ SDValue AMDGPUTargetLowering::LowerIntrinsicLRP(SDValue Op,
 }
 
 /// \brief Generate Min/Max node
-SDValue AMDGPUTargetLowering::CombineMinMax(SDNode *N,
-                                            SelectionDAG &DAG) const {
-  SDLoc DL(N);
-  EVT VT = N->getValueType(0);
-
-  SDValue LHS = N->getOperand(0);
-  SDValue RHS = N->getOperand(1);
-  SDValue True = N->getOperand(2);
-  SDValue False = N->getOperand(3);
-  SDValue CC = N->getOperand(4);
-
-  if (VT != MVT::f32 ||
-      !((LHS == True && RHS == False) || (LHS == False && RHS == True))) {
+SDValue AMDGPUTargetLowering::CombineFMinMax(SDLoc DL,
+                                             EVT VT,
+                                             SDValue LHS,
+                                             SDValue RHS,
+                                             SDValue True,
+                                             SDValue False,
+                                             SDValue CC,
+                                             SelectionDAG &DAG) const {
+  if (!(LHS == True && RHS == False) && !(LHS == False && RHS == True))
     return SDValue();
-  }
 
   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(CC)->get();
   switch (CCOpcode) {
@@ -1029,14 +1025,15 @@ SDValue AMDGPUTargetLowering::CombineMinMax(SDNode *N,
   case ISD::SETTRUE2:
   case ISD::SETUO:
   case ISD::SETO:
-    llvm_unreachable("Operation should already be optimised!");
+    break;
   case ISD::SETULE:
   case ISD::SETULT:
   case ISD::SETOLE:
   case ISD::SETOLT:
   case ISD::SETLE:
   case ISD::SETLT: {
-    unsigned Opc = (LHS == True) ? AMDGPUISD::FMIN : AMDGPUISD::FMAX;
+    unsigned Opc
+      = (LHS == True) ? AMDGPUISD::FMIN_LEGACY : AMDGPUISD::FMAX_LEGACY;
     return DAG.getNode(Opc, DL, VT, LHS, RHS);
   }
   case ISD::SETGT:
@@ -1045,7 +1042,8 @@ SDValue AMDGPUTargetLowering::CombineMinMax(SDNode *N,
   case ISD::SETOGE:
   case ISD::SETUGT:
   case ISD::SETOGT: {
-    unsigned Opc = (LHS == True) ? AMDGPUISD::FMAX : AMDGPUISD::FMIN;
+    unsigned Opc
+      = (LHS == True) ? AMDGPUISD::FMAX_LEGACY : AMDGPUISD::FMIN_LEGACY;
     return DAG.getNode(Opc, DL, VT, LHS, RHS);
   }
   case ISD::SETCC_INVALID:
@@ -1054,6 +1052,45 @@ SDValue AMDGPUTargetLowering::CombineMinMax(SDNode *N,
   return SDValue();
 }
 
+/// \brief Generate Min/Max node
+SDValue AMDGPUTargetLowering::CombineIMinMax(SDLoc DL,
+                                             EVT VT,
+                                             SDValue LHS,
+                                             SDValue RHS,
+                                             SDValue True,
+                                             SDValue False,
+                                             SDValue CC,
+                                             SelectionDAG &DAG) const {
+  if (!(LHS == True && RHS == False) && !(LHS == False && RHS == True))
+    return SDValue();
+
+  ISD::CondCode CCOpcode = cast<CondCodeSDNode>(CC)->get();
+  switch (CCOpcode) {
+  case ISD::SETULE:
+  case ISD::SETULT: {
+    unsigned Opc = (LHS == True) ? AMDGPUISD::UMIN : AMDGPUISD::UMAX;
+    return DAG.getNode(Opc, DL, VT, LHS, RHS);
+  }
+  case ISD::SETLE:
+  case ISD::SETLT: {
+    unsigned Opc = (LHS == True) ? AMDGPUISD::SMIN : AMDGPUISD::SMAX;
+    return DAG.getNode(Opc, DL, VT, LHS, RHS);
+  }
+  case ISD::SETGT:
+  case ISD::SETGE: {
+    unsigned Opc = (LHS == True) ? AMDGPUISD::SMAX : AMDGPUISD::SMIN;
+    return DAG.getNode(Opc, DL, VT, LHS, RHS);
+  }
+  case ISD::SETUGE:
+  case ISD::SETUGT: {
+    unsigned Opc = (LHS == True) ? AMDGPUISD::UMAX : AMDGPUISD::UMIN;
+    return DAG.getNode(Opc, DL, VT, LHS, RHS);
+  }
+  default:
+    return SDValue();
+  }
+}
+
 SDValue AMDGPUTargetLowering::ScalarizeVectorLoad(const SDValue Op,
                                                   SelectionDAG &DAG) const {
   LoadSDNode *Load = cast<LoadSDNode>(Op);
@@ -2110,9 +2147,51 @@ SDValue AMDGPUTargetLowering::PerformDAGCombine(SDNode *N,
       simplifyI24(N1, DCI);
       return SDValue();
     }
-    case ISD::SELECT_CC: {
-      return CombineMinMax(N, DAG);
+  case ISD::SELECT_CC: {
+    SDLoc DL(N);
+    EVT VT = N->getValueType(0);
+
+    if (VT == MVT::f32 ||
+        (VT == MVT::f64 &&
+         Subtarget->getGeneration() >= AMDGPUSubtarget::SOUTHERN_ISLANDS)) {
+      SDValue LHS = N->getOperand(0);
+      SDValue RHS = N->getOperand(1);
+      SDValue True = N->getOperand(2);
+      SDValue False = N->getOperand(3);
+      SDValue CC = N->getOperand(4);
+
+      return CombineFMinMax(DL, VT, LHS, RHS, True, False, CC, DAG);
     }
+
+    break;
+  }
+  case ISD::SELECT: {
+    SDValue Cond = N->getOperand(0);
+    if (Cond.getOpcode() == ISD::SETCC) {
+      SDLoc DL(N);
+      EVT VT = N->getValueType(0);
+      SDValue LHS = Cond.getOperand(0);
+      SDValue RHS = Cond.getOperand(1);
+      SDValue CC = Cond.getOperand(2);
+
+      SDValue True = N->getOperand(1);
+      SDValue False = N->getOperand(2);
+
+      if (VT == MVT::f32 ||
+          (VT == MVT::f64 &&
+           Subtarget->getGeneration() >= AMDGPUSubtarget::SOUTHERN_ISLANDS)) {
+        return CombineFMinMax(DL, VT, LHS, RHS, True, False, CC, DAG);
+      }
+
+      // TODO: Implement min / max Evergreen instructions.
+      if (VT == MVT::i32 &&
+          Subtarget->getGeneration() >= AMDGPUSubtarget::SOUTHERN_ISLANDS) {
+        return CombineIMinMax(DL, VT, LHS, RHS, True, False, CC, DAG);
+      }
+    }
+
+    break;
+  }
   case AMDGPUISD::BFE_I32:
   case AMDGPUISD::BFE_U32: {
     assert(!N->getValueType(0).isVector() &&
@@ -2289,12 +2368,18 @@ const char* AMDGPUTargetLowering::getTargetNodeName(unsigned Opcode) const {
   NODE_NAME_CASE(FRACT)
   NODE_NAME_CASE(CLAMP)
   NODE_NAME_CASE(MAD)
-  NODE_NAME_CASE(FMAX)
+  NODE_NAME_CASE(FMAX_LEGACY)
   NODE_NAME_CASE(SMAX)
   NODE_NAME_CASE(UMAX)
-  NODE_NAME_CASE(FMIN)
+  NODE_NAME_CASE(FMIN_LEGACY)
   NODE_NAME_CASE(SMIN)
   NODE_NAME_CASE(UMIN)
+  NODE_NAME_CASE(FMAX3)
+  NODE_NAME_CASE(SMAX3)
+  NODE_NAME_CASE(UMAX3)
+  NODE_NAME_CASE(FMIN3)
+  NODE_NAME_CASE(SMIN3)
+  NODE_NAME_CASE(UMIN3)
   NODE_NAME_CASE(URECIP)
   NODE_NAME_CASE(DIV_SCALE)
   NODE_NAME_CASE(DIV_FMAS)