From 9201b10daac2660f2f45534f12b52e3ee3501e88 Mon Sep 17 00:00:00 2001
From: Bruno Cardoso Lopes <bruno.cardoso@gmail.com>
Date: Tue, 19 Jan 2010 17:00:43 +0000
Subject: [PATCH] On pic function calls some arguments were marked dead and the
 instruction to load those args removed. This fix PR6071

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93880 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/Mips/MipsISelDAGToDAG.cpp | 35 ++++++++++++++++++++--------
 lib/Target/Mips/MipsInstrInfo.td     | 10 ++++----
 2 files changed, 30 insertions(+), 15 deletions(-)

diff --git a/lib/Target/Mips/MipsISelDAGToDAG.cpp b/lib/Target/Mips/MipsISelDAGToDAG.cpp
index 4cd64989ea5..f2005d0bff0 100644
--- a/lib/Target/Mips/MipsISelDAGToDAG.cpp
+++ b/lib/Target/Mips/MipsISelDAGToDAG.cpp
@@ -495,10 +495,15 @@ SDNode* MipsDAGToDAGISel::Select(SDNode *Node) {
     /// be loaded with 3 instructions. 
     case MipsISD::JmpLink: {
       if (TM.getRelocationModel() == Reloc::PIC_) {
+        unsigned LastOpNum = Node->getNumOperands()-1;
+
         SDValue Chain  = Node->getOperand(0);
         SDValue Callee = Node->getOperand(1);
-        SDValue T9Reg = CurDAG->getRegister(Mips::T9, MVT::i32);
-        SDValue InFlag(0, 0);
+        SDValue InFlag;
+
+        // Skip the incomming flag if present
+        if (Node->getOperand(LastOpNum).getValueType() == MVT::Flag)
+          LastOpNum--;
 
         if ( (isa<GlobalAddressSDNode>(Callee)) ||
              (isa<ExternalSymbolSDNode>(Callee)) )
@@ -513,18 +518,28 @@ SDNode* MipsDAGToDAGISel::Select(SDNode *Node) {
           Chain = Load.getValue(1);
 
           // Call target must be on T9
-          Chain = CurDAG->getCopyToReg(Chain, dl, T9Reg, Load, InFlag);
+          Chain = CurDAG->getCopyToReg(Chain, dl, Mips::T9, Load, InFlag);
         } else 
           /// Indirect call
-          Chain = CurDAG->getCopyToReg(Chain, dl, T9Reg, Callee, InFlag);
+          Chain = CurDAG->getCopyToReg(Chain, dl, Mips::T9, Callee, InFlag);
+
+        // Map the JmpLink operands to JALR
+        SDVTList NodeTys = CurDAG->getVTList(MVT::Other, MVT::Flag);
+        SmallVector<SDValue, 8> Ops;
+        Ops.push_back(CurDAG->getRegister(Mips::T9, MVT::i32));
+
+        for (unsigned i = 2, e = LastOpNum+1; i != e; ++i)
+          Ops.push_back(Node->getOperand(i));
+        Ops.push_back(Chain);
+        Ops.push_back(Chain.getValue(1));
 
         // Emit Jump and Link Register
-        SDNode *ResNode = CurDAG->getMachineNode(Mips::JALR, dl, MVT::Other,
-                                  MVT::Flag, T9Reg, Chain);
-        Chain  = SDValue(ResNode, 0);
-        InFlag = SDValue(ResNode, 1);
-        ReplaceUses(SDValue(Node, 0), Chain);
-        ReplaceUses(SDValue(Node, 1), InFlag);
+        SDNode *ResNode = CurDAG->getMachineNode(Mips::JALR, dl, NodeTys, 
+                                  &Ops[0], Ops.size());
+
+        // Replace Chain and InFlag
+        ReplaceUses(SDValue(Node, 0), SDValue(ResNode, 0));
+        ReplaceUses(SDValue(Node, 1), SDValue(ResNode, 1));
         return ResNode;
       } 
     }
diff --git a/lib/Target/Mips/MipsInstrInfo.td b/lib/Target/Mips/MipsInstrInfo.td
index 46cf43e422d..e67bcbfc177 100644
--- a/lib/Target/Mips/MipsInstrInfo.td
+++ b/lib/Target/Mips/MipsInstrInfo.td
@@ -28,8 +28,8 @@ def SDT_MipsCallSeqStart : SDCallSeqStart<[SDTCisVT<0, i32>]>;
 def SDT_MipsCallSeqEnd   : SDCallSeqEnd<[SDTCisVT<0, i32>, SDTCisVT<1, i32>]>;
 
 // Call
-def MipsJmpLink : SDNode<"MipsISD::JmpLink",SDT_MipsJmpLink, [SDNPHasChain,
-                         SDNPOutFlag]>;
+def MipsJmpLink : SDNode<"MipsISD::JmpLink",SDT_MipsJmpLink, 
+                         [SDNPHasChain, SDNPOutFlag, SDNPOptInFlag]>;
 
 // Hi and Lo nodes are used to handle global addresses. Used on 
 // MipsISelLowering to lower stuff like GlobalAddress, ExternalSymbol 
@@ -306,7 +306,7 @@ let isCall=1, hasDelaySlot=1,
   class JumpLink<bits<6> op, string instr_asm>:
     FJ< op,
         (outs),
-        (ins calltarget:$target),
+        (ins calltarget:$target, variable_ops),
         !strconcat(instr_asm, "\t$target"),
         [(MipsJmpLink imm:$target)], IIBranch>;
 
@@ -315,14 +315,14 @@ let isCall=1, hasDelaySlot=1,
     FR< op,
         func,
         (outs),
-        (ins CPURegs:$rs),
+        (ins CPURegs:$rs, variable_ops),
         !strconcat(instr_asm, "\t$rs"),
         [(MipsJmpLink CPURegs:$rs)], IIBranch>;
 
   class BranchLink<string instr_asm>:
     FI< 0x1,
         (outs),
-        (ins CPURegs:$rs, brtarget:$target),
+        (ins CPURegs:$rs, brtarget:$target, variable_ops),
         !strconcat(instr_asm, "\t$rs, $target"),
         [], IIBranch>;
 }
-- 
2.34.1