DAG: Avoid using getLibcallName for function support test (#170583)

Author: arsenm

llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp

@@ -3878,7 +3878,7 @@ bool SelectionDAGLegalize::ExpandNode(SDNode *Node) {
     RTLIB::Libcall LC = RTLIB::getLDEXP(VT);
     // Use the LibCall instead, it is very likely faster
     // FIXME: Use separate LibCall action.
-    if (TLI.getLibcallName(LC))
+    if (TLI.getLibcallImpl(LC) != RTLIB::Unsupported)
       break;
 
     if (SDValue Expanded = expandLdexp(Node)) {
@@ -3893,7 +3893,7 @@ bool SelectionDAGLegalize::ExpandNode(SDNode *Node) {
     RTLIB::Libcall LC = RTLIB::getFREXP(Node->getValueType(0));
     // Use the LibCall instead, it is very likely faster
     // FIXME: Use separate LibCall action.
-    if (TLI.getLibcallName(LC))
+    if (TLI.getLibcallImpl(LC) != RTLIB::Unsupported)
       break;
 
     if (SDValue Expanded = expandFrexp(Node)) {
@@ -4695,7 +4695,7 @@ void SelectionDAGLegalize::ConvertNodeToLibcall(SDNode *Node) {
     RTLIB::Libcall LC = RTLIB::getOUTLINE_ATOMIC(Opc, Order, VT);
     EVT RetVT = Node->getValueType(0);
     SmallVector<SDValue, 4> Ops;
-    if (TLI.getLibcallName(LC)) {
+    if (TLI.getLibcallImpl(LC) != RTLIB::Unsupported) {
       // If outline atomic available, prepare its arguments and expand.
       Ops.append(Node->op_begin() + 2, Node->op_end());
       Ops.push_back(Node->getOperand(1));
@@ -4961,7 +4961,7 @@ void SelectionDAGLegalize::ConvertNodeToLibcall(SDNode *Node) {
   case ISD::STRICT_FPOWI: {
     RTLIB::Libcall LC = RTLIB::getPOWI(Node->getSimpleValueType(0));
     assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unexpected fpowi.");
-    if (!TLI.getLibcallName(LC)) {
+    if (TLI.getLibcallImpl(LC) == RTLIB::Unsupported) {
       // Some targets don't have a powi libcall; use pow instead.
       if (Node->isStrictFPOpcode()) {
         SDValue Exponent =

llvm/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp

@@ -717,7 +717,7 @@ SDValue DAGTypeLegalizer::SoftenFloatRes_ExpOp(SDNode *N) {
   RTLIB::Libcall LC = IsPowI ? RTLIB::getPOWI(N->getValueType(0))
                              : RTLIB::getLDEXP(N->getValueType(0));
   assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unexpected fpowi.");
-  if (!TLI.getLibcallName(LC)) {
+  if (TLI.getLibcallImpl(LC) == RTLIB::Unsupported) {
     // Some targets don't have a powi libcall; use pow instead.
     // FIXME: Implement this if some target needs it.
     DAG.getContext()->emitError("do not know how to soften fpowi to fpow");
@@ -802,7 +802,7 @@ bool DAGTypeLegalizer::SoftenFloatRes_UnaryWithTwoFPResults(
   assert(VT == N->getValueType(1) &&
          "expected both return values to have the same type");
 
-  if (!TLI.getLibcallName(LC))
+  if (TLI.getLibcallImpl(LC) == RTLIB::Unsupported)
     return false;
 
   EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), VT);
@@ -862,7 +862,8 @@ SDValue DAGTypeLegalizer::SoftenFloatRes_FSINCOS(SDNode *N) {
   RTLIB::Libcall CosLC = RTLIB::getCOS(VT);
 
   SDValue SoftSin, SoftCos;
-  if (!TLI.getLibcallName(SinLC) || !TLI.getLibcallName(CosLC)) {
+  if (TLI.getLibcallImpl(SinLC) == RTLIB::Unsupported ||
+      TLI.getLibcallImpl(CosLC) == RTLIB::Unsupported) {
     DAG.getContext()->emitError("do not know how to soften fsincos");
 
     EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), VT);

llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp

@@ -2692,7 +2692,7 @@ SDValue DAGTypeLegalizer::PromoteIntOp_ExpOp(SDNode *N) {
   RTLIB::Libcall LC = IsPowI ? RTLIB::getPOWI(N->getValueType(0))
                              : RTLIB::getLDEXP(N->getValueType(0));
 
-  if (LC == RTLIB::UNKNOWN_LIBCALL || !TLI.getLibcallName(LC)) {
+  if (TLI.getLibcallImpl(LC) == RTLIB::Unsupported) {
     // Scalarize vector FPOWI instead of promoting the type. This allows the
     // scalar FPOWIs to be visited and converted to libcalls before promoting
     // the type.