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-rw-r--r--lib/Target/X86/X86FrameLowering.cpp73
-rw-r--r--lib/Target/X86/X86FrameLowering.h4
-rw-r--r--lib/Target/X86/X86ISelLowering.cpp5
-rw-r--r--lib/Target/X86/X86MCInstLower.cpp64
4 files changed, 145 insertions, 1 deletions
diff --git a/lib/Target/X86/X86FrameLowering.cpp b/lib/Target/X86/X86FrameLowering.cpp
index b9920b1b84c..278e4f910d4 100644
--- a/lib/Target/X86/X86FrameLowering.cpp
+++ b/lib/Target/X86/X86FrameLowering.cpp
@@ -1135,6 +1135,79 @@ int X86FrameLowering::getFrameIndexReference(const MachineFunction &MF, int FI,
return getFrameIndexOffset(MF, FI);
}
+// Simplified from getFrameIndexOffset keeping only StackPointer cases
+int X86FrameLowering::getFrameIndexOffsetFromSP(const MachineFunction &MF, int FI) const {
+ const X86RegisterInfo *RegInfo =
+ static_cast<const X86RegisterInfo*>(MF.getSubtarget().getRegisterInfo());
+ const MachineFrameInfo *MFI = MF.getFrameInfo();
+ const uint64_t StackSize = MFI->getStackSize(); //not including dynamic realign
+
+ {
+#ifndef NDEBUG
+ // Note: LLVM arranges the stack as:
+ // Args > Saved RetPC (<--FP) > CSRs > dynamic alignment (<--BP)
+ // > "Stack Slots" (<--SP)
+ // We can always address StackSlots from RSP. We can usually (unless
+ // needsStackRealignment) address CSRs from RSP, but sometimes need to
+ // address them from RBP. FixedObjects can be placed anywhere in the stack
+ // frame depending on their specific requirements (i.e. we can actually
+ // refer to arguments to the function which are stored in the *callers*
+ // frame). As a result, THE RESULT OF THIS CALL IS MEANINGLESS FOR CSRs
+ // AND FixedObjects IFF needsStackRealignment or hasVarSizedObject.
+
+ assert(!RegInfo->hasBasePointer(MF) && "we don't handle this case");
+
+ // We don't handle tail calls, and shouldn't be seeing them
+ // either.
+ int TailCallReturnAddrDelta =
+ MF.getInfo<X86MachineFunctionInfo>()->getTCReturnAddrDelta();
+ assert(!(TailCallReturnAddrDelta < 0) && "we don't handle this case!");
+#endif
+ }
+
+ // This is how the math works out:
+ //
+ // %rsp grows (i.e. gets lower) left to right. Each box below is
+ // one word (eight bytes). Obj0 is the stack slot we're trying to
+ // get to.
+ //
+ // ----------------------------------
+ // | BP | Obj0 | Obj1 | ... | ObjN |
+ // ----------------------------------
+ // ^ ^ ^ ^
+ // A B C E
+ //
+ // A is the incoming stack pointer.
+ // (B - A) is the local area offset (-8 for x86-64) [1]
+ // (C - A) is the Offset returned by MFI->getObjectOffset for Obj0 [2]
+ //
+ // |(E - B)| is the StackSize (absolute value, positive). For a
+ // stack that grown down, this works out to be (B - E). [3]
+ //
+ // E is also the value of %rsp after stack has been set up, and we
+ // want (C - E) -- the value we can add to %rsp to get to Obj0. Now
+ // (C - E) == (C - A) - (B - A) + (B - E)
+ // { Using [1], [2] and [3] above }
+ // == getObjectOffset - LocalAreaOffset + StackSize
+ //
+
+ // Get the Offset from the StackPointer
+ int Offset = MFI->getObjectOffset(FI) - getOffsetOfLocalArea();
+
+ return Offset + StackSize;
+}
+// Simplified from getFrameIndexReference keeping only StackPointer cases
+int X86FrameLowering::getFrameIndexReferenceFromSP(const MachineFunction &MF, int FI,
+ unsigned &FrameReg) const {
+ const X86RegisterInfo *RegInfo =
+ static_cast<const X86RegisterInfo*>(MF.getSubtarget().getRegisterInfo());
+
+ assert(!RegInfo->hasBasePointer(MF) && "we don't handle this case");
+
+ FrameReg = RegInfo->getStackRegister();
+ return getFrameIndexOffsetFromSP(MF, FI);
+}
+
bool X86FrameLowering::assignCalleeSavedSpillSlots(
MachineFunction &MF, const TargetRegisterInfo *TRI,
std::vector<CalleeSavedInfo> &CSI) const {
diff --git a/lib/Target/X86/X86FrameLowering.h b/lib/Target/X86/X86FrameLowering.h
index 7740c3ad6f3..2ee71159c19 100644
--- a/lib/Target/X86/X86FrameLowering.h
+++ b/lib/Target/X86/X86FrameLowering.h
@@ -69,6 +69,10 @@ public:
int getFrameIndexReference(const MachineFunction &MF, int FI,
unsigned &FrameReg) const override;
+ int getFrameIndexOffsetFromSP(const MachineFunction &MF, int FI) const;
+ int getFrameIndexReferenceFromSP(const MachineFunction &MF, int FI,
+ unsigned &FrameReg) const override;
+
void eliminateCallFramePseudoInstr(MachineFunction &MF,
MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI) const override;
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index b67bbcb39c3..7faa58cf377 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -21346,6 +21346,11 @@ X86TargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
case X86::EH_SjLj_LongJmp64:
return emitEHSjLjLongJmp(MI, BB);
+ case TargetOpcode::STATEPOINT:
+ // As an implementation detail, STATEPOINT shares the STACKMAP format at
+ // this point in the process. We diverge later.
+ return emitPatchPoint(MI, BB);
+
case TargetOpcode::STACKMAP:
case TargetOpcode::PATCHPOINT:
return emitPatchPoint(MI, BB);
diff --git a/lib/Target/X86/X86MCInstLower.cpp b/lib/Target/X86/X86MCInstLower.cpp
index 4e0d594238c..6a10916aa60 100644
--- a/lib/Target/X86/X86MCInstLower.cpp
+++ b/lib/Target/X86/X86MCInstLower.cpp
@@ -808,6 +808,66 @@ static void EmitNops(MCStreamer &OS, unsigned NumBytes, bool Is64Bit, const MCSu
} // while (NumBytes)
}
+static void LowerSTATEPOINT(MCStreamer &OS, StackMaps &SM,
+ const MachineInstr &MI, bool Is64Bit,
+ const TargetMachine& TM,
+ const MCSubtargetInfo& STI,
+ X86MCInstLower &MCInstLowering) {
+ assert(Is64Bit && "Statepoint currently only supports X86-64");
+
+ // We need to record the frame size for stack walking
+ const MachineFunction* MF = MI.getParent()->getParent();
+ assert(MF && "can't find machine function?");
+
+ //
+ // Emit call instruction
+ //
+
+ // Lower call target and choose correct opcode
+ const MachineOperand &call_target = StatepointOpers(&MI).getCallTarget();
+ MCOperand call_target_mcop;
+ unsigned call_opcode;
+ switch (call_target.getType()) {
+ case MachineOperand::MO_GlobalAddress:
+ case MachineOperand::MO_ExternalSymbol:
+ call_target_mcop = MCInstLowering.LowerSymbolOperand(
+ call_target,
+ MCInstLowering.GetSymbolFromOperand(call_target));
+ call_opcode = X86::CALL64pcrel32;
+ // Currently, we only support relative addressing with statepoints.
+ // Otherwise, we'll need a scratch register to hold the target
+ // address. You'll fail asserts during load & relocation if this
+ // symbol is to far away. (TODO: support non-relative addressing)
+ break;
+ case MachineOperand::MO_Immediate:
+ call_target_mcop = MCOperand::CreateImm(call_target.getImm());
+ call_opcode = X86::CALL64pcrel32;
+ // Currently, we only support relative addressing with statepoints.
+ // Otherwise, we'll need a scratch register to hold the target
+ // immediate. You'll fail asserts during load & relocation if this
+ // address is to far away. (TODO: support non-relative addressing)
+ break;
+ case MachineOperand::MO_Register:
+ call_target_mcop = MCOperand::CreateReg(call_target.getReg());
+ call_opcode = X86::CALL64r;
+ break;
+ default:
+ llvm_unreachable("Unsupported operand type in statepoint call target");
+ break;
+ }
+
+ // Emit call
+ MCInst call_inst;
+ call_inst.setOpcode(call_opcode);
+ call_inst.addOperand(call_target_mcop);
+ OS.EmitInstruction(call_inst, STI);
+
+ // Record our statepoint node in the same section used by STACKMAP
+ // and PATCHPOINT
+ SM.recordStatepoint(MI);
+}
+
+
// Lower a stackmap of the form:
// <id>, <shadowBytes>, ...
void X86AsmPrinter::LowerSTACKMAP(const MachineInstr &MI) {
@@ -1030,7 +1090,9 @@ void X86AsmPrinter::EmitInstruction(const MachineInstr *MI) {
.addExpr(DotExpr));
return;
}
-
+ case TargetOpcode::STATEPOINT:
+ return LowerSTATEPOINT(OutStreamer, SM, *MI, Subtarget->is64Bit(), TM,
+ getSubtargetInfo(), MCInstLowering);
case TargetOpcode::STACKMAP:
return LowerSTACKMAP(*MI);