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-rw-r--r--contrib/llvm/lib/CodeGen/CallingConvLower.cpp247
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diff --git a/contrib/llvm/lib/CodeGen/CallingConvLower.cpp b/contrib/llvm/lib/CodeGen/CallingConvLower.cpp
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+//===-- CallingConvLower.cpp - Calling Conventions ------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the CCState class, used for lowering and implementing
+// calling conventions.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/CallingConvLower.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/SaveAndRestore.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetLowering.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
+using namespace llvm;
+
+CCState::CCState(CallingConv::ID CC, bool isVarArg, MachineFunction &mf,
+ SmallVectorImpl<CCValAssign> &locs, LLVMContext &C)
+ : CallingConv(CC), IsVarArg(isVarArg), MF(mf),
+ TRI(*MF.getSubtarget().getRegisterInfo()), Locs(locs), Context(C),
+ CallOrPrologue(Unknown) {
+ // No stack is used.
+ StackOffset = 0;
+
+ clearByValRegsInfo();
+ UsedRegs.resize((TRI.getNumRegs()+31)/32);
+}
+
+/// Allocate space on the stack large enough to pass an argument by value.
+/// The size and alignment information of the argument is encoded in
+/// its parameter attribute.
+void CCState::HandleByVal(unsigned ValNo, MVT ValVT,
+ MVT LocVT, CCValAssign::LocInfo LocInfo,
+ int MinSize, int MinAlign,
+ ISD::ArgFlagsTy ArgFlags) {
+ unsigned Align = ArgFlags.getByValAlign();
+ unsigned Size = ArgFlags.getByValSize();
+ if (MinSize > (int)Size)
+ Size = MinSize;
+ if (MinAlign > (int)Align)
+ Align = MinAlign;
+ MF.getFrameInfo()->ensureMaxAlignment(Align);
+ MF.getSubtarget().getTargetLowering()->HandleByVal(this, Size, Align);
+ Size = unsigned(RoundUpToAlignment(Size, MinAlign));
+ unsigned Offset = AllocateStack(Size, Align);
+ addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
+}
+
+/// Mark a register and all of its aliases as allocated.
+void CCState::MarkAllocated(unsigned Reg) {
+ for (MCRegAliasIterator AI(Reg, &TRI, true); AI.isValid(); ++AI)
+ UsedRegs[*AI/32] |= 1 << (*AI&31);
+}
+
+/// Analyze an array of argument values,
+/// incorporating info about the formals into this state.
+void
+CCState::AnalyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Ins,
+ CCAssignFn Fn) {
+ unsigned NumArgs = Ins.size();
+
+ for (unsigned i = 0; i != NumArgs; ++i) {
+ MVT ArgVT = Ins[i].VT;
+ ISD::ArgFlagsTy ArgFlags = Ins[i].Flags;
+ if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
+#ifndef NDEBUG
+ dbgs() << "Formal argument #" << i << " has unhandled type "
+ << EVT(ArgVT).getEVTString() << '\n';
+#endif
+ llvm_unreachable(nullptr);
+ }
+ }
+}
+
+/// Analyze the return values of a function, returning true if the return can
+/// be performed without sret-demotion and false otherwise.
+bool CCState::CheckReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
+ CCAssignFn Fn) {
+ // Determine which register each value should be copied into.
+ for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
+ MVT VT = Outs[i].VT;
+ ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
+ if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this))
+ return false;
+ }
+ return true;
+}
+
+/// Analyze the returned values of a return,
+/// incorporating info about the result values into this state.
+void CCState::AnalyzeReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
+ CCAssignFn Fn) {
+ // Determine which register each value should be copied into.
+ for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
+ MVT VT = Outs[i].VT;
+ ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
+ if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this)) {
+#ifndef NDEBUG
+ dbgs() << "Return operand #" << i << " has unhandled type "
+ << EVT(VT).getEVTString() << '\n';
+#endif
+ llvm_unreachable(nullptr);
+ }
+ }
+}
+
+/// Analyze the outgoing arguments to a call,
+/// incorporating info about the passed values into this state.
+void CCState::AnalyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Outs,
+ CCAssignFn Fn) {
+ unsigned NumOps = Outs.size();
+ for (unsigned i = 0; i != NumOps; ++i) {
+ MVT ArgVT = Outs[i].VT;
+ ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
+ if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
+#ifndef NDEBUG
+ dbgs() << "Call operand #" << i << " has unhandled type "
+ << EVT(ArgVT).getEVTString() << '\n';
+#endif
+ llvm_unreachable(nullptr);
+ }
+ }
+}
+
+/// Same as above except it takes vectors of types and argument flags.
+void CCState::AnalyzeCallOperands(SmallVectorImpl<MVT> &ArgVTs,
+ SmallVectorImpl<ISD::ArgFlagsTy> &Flags,
+ CCAssignFn Fn) {
+ unsigned NumOps = ArgVTs.size();
+ for (unsigned i = 0; i != NumOps; ++i) {
+ MVT ArgVT = ArgVTs[i];
+ ISD::ArgFlagsTy ArgFlags = Flags[i];
+ if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
+#ifndef NDEBUG
+ dbgs() << "Call operand #" << i << " has unhandled type "
+ << EVT(ArgVT).getEVTString() << '\n';
+#endif
+ llvm_unreachable(nullptr);
+ }
+ }
+}
+
+/// Analyze the return values of a call, incorporating info about the passed
+/// values into this state.
+void CCState::AnalyzeCallResult(const SmallVectorImpl<ISD::InputArg> &Ins,
+ CCAssignFn Fn) {
+ for (unsigned i = 0, e = Ins.size(); i != e; ++i) {
+ MVT VT = Ins[i].VT;
+ ISD::ArgFlagsTy Flags = Ins[i].Flags;
+ if (Fn(i, VT, VT, CCValAssign::Full, Flags, *this)) {
+#ifndef NDEBUG
+ dbgs() << "Call result #" << i << " has unhandled type "
+ << EVT(VT).getEVTString() << '\n';
+#endif
+ llvm_unreachable(nullptr);
+ }
+ }
+}
+
+/// Same as above except it's specialized for calls that produce a single value.
+void CCState::AnalyzeCallResult(MVT VT, CCAssignFn Fn) {
+ if (Fn(0, VT, VT, CCValAssign::Full, ISD::ArgFlagsTy(), *this)) {
+#ifndef NDEBUG
+ dbgs() << "Call result has unhandled type "
+ << EVT(VT).getEVTString() << '\n';
+#endif
+ llvm_unreachable(nullptr);
+ }
+}
+
+static bool isValueTypeInRegForCC(CallingConv::ID CC, MVT VT) {
+ if (VT.isVector())
+ return true; // Assume -msse-regparm might be in effect.
+ if (!VT.isInteger())
+ return false;
+ if (CC == CallingConv::X86_VectorCall || CC == CallingConv::X86_FastCall)
+ return true;
+ return false;
+}
+
+void CCState::getRemainingRegParmsForType(SmallVectorImpl<MCPhysReg> &Regs,
+ MVT VT, CCAssignFn Fn) {
+ unsigned SavedStackOffset = StackOffset;
+ unsigned NumLocs = Locs.size();
+
+ // Set the 'inreg' flag if it is used for this calling convention.
+ ISD::ArgFlagsTy Flags;
+ if (isValueTypeInRegForCC(CallingConv, VT))
+ Flags.setInReg();
+
+ // Allocate something of this value type repeatedly until we get assigned a
+ // location in memory.
+ bool HaveRegParm = true;
+ while (HaveRegParm) {
+ if (Fn(0, VT, VT, CCValAssign::Full, Flags, *this)) {
+#ifndef NDEBUG
+ dbgs() << "Call has unhandled type " << EVT(VT).getEVTString()
+ << " while computing remaining regparms\n";
+#endif
+ llvm_unreachable(nullptr);
+ }
+ HaveRegParm = Locs.back().isRegLoc();
+ }
+
+ // Copy all the registers from the value locations we added.
+ assert(NumLocs < Locs.size() && "CC assignment failed to add location");
+ for (unsigned I = NumLocs, E = Locs.size(); I != E; ++I)
+ if (Locs[I].isRegLoc())
+ Regs.push_back(MCPhysReg(Locs[I].getLocReg()));
+
+ // Clear the assigned values and stack memory. We leave the registers marked
+ // as allocated so that future queries don't return the same registers, i.e.
+ // when i64 and f64 are both passed in GPRs.
+ StackOffset = SavedStackOffset;
+ Locs.resize(NumLocs);
+}
+
+void CCState::analyzeMustTailForwardedRegisters(
+ SmallVectorImpl<ForwardedRegister> &Forwards, ArrayRef<MVT> RegParmTypes,
+ CCAssignFn Fn) {
+ // Oftentimes calling conventions will not user register parameters for
+ // variadic functions, so we need to assume we're not variadic so that we get
+ // all the registers that might be used in a non-variadic call.
+ SaveAndRestore<bool> SavedVarArg(IsVarArg, false);
+
+ for (MVT RegVT : RegParmTypes) {
+ SmallVector<MCPhysReg, 8> RemainingRegs;
+ getRemainingRegParmsForType(RemainingRegs, RegVT, Fn);
+ const TargetLowering *TL = MF.getSubtarget().getTargetLowering();
+ const TargetRegisterClass *RC = TL->getRegClassFor(RegVT);
+ for (MCPhysReg PReg : RemainingRegs) {
+ unsigned VReg = MF.addLiveIn(PReg, RC);
+ Forwards.push_back(ForwardedRegister(VReg, PReg, RegVT));
+ }
+ }
+}
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