4 files changed, 15 insertions, 1 deletions
diff --git a/llvm/lib/Target/PowerPC/PPC.td b/llvm/lib/Target/PowerPC/PPC.td
index b40b530f4c5..ac1c3060046 100644
--- a/llvm/lib/Target/PowerPC/PPC.td
+++ b/llvm/lib/Target/PowerPC/PPC.td
@@ -136,6 +136,8 @@ def FeatureInvariantFunctionDescriptors :
   SubtargetFeature<"invariant-function-descriptors",
                    "HasInvariantFunctionDescriptors", "true",
                    "Assume function descriptors are invariant">;
+def FeatureLongCall : SubtargetFeature<"longcall", "UseLongCalls", "true",
+                                       "Always use indirect calls">;
 def FeatureHTM : SubtargetFeature<"htm", "HasHTM", "true",
                                   "Enable Hardware Transactional Memory instructions">;
 def FeatureMFTB   : SubtargetFeature<"", "FeatureMFTB", "true",
diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index f895b06ac68..09887c3e4d1 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -4695,7 +4695,9 @@ PPCTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
   ImmutableCallSite *CS                 = CLI.CS;
 
   if (isTailCall) {
-    if (Subtarget.isSVR4ABI() && Subtarget.isPPC64())
+    if (Subtarget.useLongCalls() && !(CS && CS->isMustTailCall()))
+      isTailCall = false;
+    else if (Subtarget.isSVR4ABI() && Subtarget.isPPC64())
       isTailCall =
         IsEligibleForTailCallOptimization_64SVR4(Callee, CallConv, CS,
                                                  isVarArg, Outs, Ins, DAG);
@@ -4725,6 +4727,13 @@ PPCTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
     report_fatal_error("failed to perform tail call elimination on a call "
                        "site marked musttail");
 
+  // When long calls (i.e. indirect calls) are always used, calls are always
+  // made via function pointer. If we have a function name, first translate it
+  // into a pointer.
+  if (Subtarget.useLongCalls() && isa<GlobalAddressSDNode>(Callee) &&
+      !isTailCall)
+    Callee = LowerGlobalAddress(Callee, DAG);
+
   if (Subtarget.isSVR4ABI()) {
     if (Subtarget.isPPC64())
       return LowerCall_64SVR4(Chain, Callee, CallConv, isVarArg,
diff --git a/llvm/lib/Target/PowerPC/PPCSubtarget.cpp b/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
index 603f0fccc7c..19570735295 100644
--- a/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
+++ b/llvm/lib/Target/PowerPC/PPCSubtarget.cpp
@@ -105,6 +105,7 @@ void PPCSubtarget::initializeEnvironment() {
   HasFusion = false;
   HasFloat128 = false;
   IsISA3_0 = false;
+  UseLongCalls = false;
 
   HasPOPCNTD = POPCNTD_Unavailable;
 }
diff --git a/llvm/lib/Target/PowerPC/PPCSubtarget.h b/llvm/lib/Target/PowerPC/PPCSubtarget.h
index 9fe286a3b7a..f58c7c10c8b 100644
--- a/llvm/lib/Target/PowerPC/PPCSubtarget.h
+++ b/llvm/lib/Target/PowerPC/PPCSubtarget.h
@@ -132,6 +132,7 @@ protected:
   bool HasFusion;
   bool HasFloat128;
   bool IsISA3_0;
+  bool UseLongCalls;
 
   POPCNTDKind HasPOPCNTD;
 
@@ -275,6 +276,7 @@ public:
   bool hasFusion() const { return HasFusion; }
   bool hasFloat128() const { return HasFloat128; }
   bool isISA3_0() const { return IsISA3_0; }
+  bool useLongCalls() const { return UseLongCalls; }
 
   POPCNTDKind hasPOPCNTD() const { return HasPOPCNTD; }