[mips] Make sure loads from lazy-binding entries do not get CSE'd or hoisted out
of loops.
Previously, two consecutive calls to function "func" would result in the
following sequence of instructions:
1. load $16, %got(func)($gp) // load address of lazy-binding stub.
2. move $25, $16
3. jalr $25 // jump to lazy-binding stub.
4. nop
5. move $25, $16
6. jalr $25 // jump to lazy-binding stub again.
With this patch, the second call directly jumps to func's address, bypassing
the lazy-binding resolution routine:
1. load $25, %got(func)($gp) // load address of lazy-binding stub.
2. jalr $25 // jump to lazy-binding stub.
3. nop
4. load $25, %got(func)($gp) // load resolved address of func.
5. jalr $25 // directly jump to func.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191591 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Mips/MipsISelLowering.cpp b/lib/Target/Mips/MipsISelLowering.cpp
index 5aab3f8..3eb2dfb 100644
--- a/lib/Target/Mips/MipsISelLowering.cpp
+++ b/lib/Target/Mips/MipsISelLowering.cpp
@@ -1468,10 +1468,12 @@
if (LargeGOT)
return getAddrGlobalLargeGOT(N, Ty, DAG, MipsII::MO_GOT_HI16,
- MipsII::MO_GOT_LO16);
+ MipsII::MO_GOT_LO16, DAG.getEntryNode(),
+ MachinePointerInfo::getGOT());
return getAddrGlobal(N, Ty, DAG,
- HasMips64 ? MipsII::MO_GOT_DISP : MipsII::MO_GOT16);
+ HasMips64 ? MipsII::MO_GOT_DISP : MipsII::MO_GOT16,
+ DAG.getEntryNode(), MachinePointerInfo::getGOT());
}
SDValue MipsTargetLowering::lowerBlockAddress(SDValue Op,
@@ -2313,6 +2315,7 @@
MachineFunction &MF = DAG.getMachineFunction();
MachineFrameInfo *MFI = MF.getFrameInfo();
const TargetFrameLowering *TFL = MF.getTarget().getFrameLowering();
+ MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
bool IsPIC = getTargetMachine().getRelocationModel() == Reloc::PIC_;
// Analyze operands of the call, assigning locations to each operand.
@@ -2446,29 +2449,36 @@
if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
if (IsPICCall) {
- InternalLinkage = G->getGlobal()->hasInternalLinkage();
+ const GlobalValue *Val = G->getGlobal();
+ InternalLinkage = Val->hasInternalLinkage();
if (InternalLinkage)
Callee = getAddrLocal(G, Ty, DAG, HasMips64);
else if (LargeGOT)
Callee = getAddrGlobalLargeGOT(G, Ty, DAG, MipsII::MO_CALL_HI16,
- MipsII::MO_CALL_LO16);
+ MipsII::MO_CALL_LO16, Chain,
+ FuncInfo->callPtrInfo(Val));
else
- Callee = getAddrGlobal(G, Ty, DAG, MipsII::MO_GOT_CALL);
+ Callee = getAddrGlobal(G, Ty, DAG, MipsII::MO_GOT_CALL, Chain,
+ FuncInfo->callPtrInfo(Val));
} else
Callee = DAG.getTargetGlobalAddress(G->getGlobal(), DL, getPointerTy(), 0,
MipsII::MO_NO_FLAG);
GlobalOrExternal = true;
}
else if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee)) {
+ const char *Sym = S->getSymbol();
+
if (!IsN64 && !IsPIC) // !N64 && static
- Callee = DAG.getTargetExternalSymbol(S->getSymbol(), getPointerTy(),
+ Callee = DAG.getTargetExternalSymbol(Sym, getPointerTy(),
MipsII::MO_NO_FLAG);
else if (LargeGOT)
Callee = getAddrGlobalLargeGOT(S, Ty, DAG, MipsII::MO_CALL_HI16,
- MipsII::MO_CALL_LO16);
+ MipsII::MO_CALL_LO16, Chain,
+ FuncInfo->callPtrInfo(Sym));
else // N64 || PIC
- Callee = getAddrGlobal(S, Ty, DAG, MipsII::MO_GOT_CALL);
+ Callee = getAddrGlobal(S, Ty, DAG, MipsII::MO_GOT_CALL, Chain,
+ FuncInfo->callPtrInfo(Sym));
GlobalOrExternal = true;
}