[llvm] r265291 - [SystemZ] Support llvm.frameaddress/llvm.returnaddress intrinsics
Ulrich Weigand via llvm-commits
llvm-commits at lists.llvm.org
Mon Apr 4 05:44:56 PDT 2016
Author: uweigand
Date: Mon Apr 4 07:44:55 2016
New Revision: 265291
URL: http://llvm.org/viewvc/llvm-project?rev=265291&view=rev
Log:
[SystemZ] Support llvm.frameaddress/llvm.returnaddress intrinsics
Enable the SystemZ back-end to lower FRAMEADDR and RETURNADDR, which
previously would cause the back-end to crash. Currently, only a
frame count of zero is supported.
Author: bryanpkc
Differential Revision: http://reviews.llvm.org/D18514
Added:
llvm/trunk/test/CodeGen/SystemZ/frameaddr-01.ll
llvm/trunk/test/CodeGen/SystemZ/ret-addr-01.ll
Modified:
llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp
llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.h
llvm/trunk/lib/Target/SystemZ/SystemZMachineFunctionInfo.h
Modified: llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp?rev=265291&r1=265290&r2=265291&view=diff
==============================================================================
--- llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp Mon Apr 4 07:44:55 2016
@@ -2676,6 +2676,57 @@ SDValue SystemZTargetLowering::lowerCons
return DAG.getNode(SystemZISD::PCREL_WRAPPER, DL, PtrVT, Result);
}
+SDValue SystemZTargetLowering::lowerFRAMEADDR(SDValue Op,
+ SelectionDAG &DAG) const {
+ MachineFunction &MF = DAG.getMachineFunction();
+ MachineFrameInfo *MFI = MF.getFrameInfo();
+ MFI->setFrameAddressIsTaken(true);
+
+ SDLoc DL(Op);
+ unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
+ EVT PtrVT = getPointerTy(DAG.getDataLayout());
+
+ // If the back chain frame index has not been allocated yet, do so.
+ SystemZMachineFunctionInfo *FI = MF.getInfo<SystemZMachineFunctionInfo>();
+ int BackChainIdx = FI->getFramePointerSaveIndex();
+ if (!BackChainIdx) {
+ // By definition, the frame address is the address of the back chain.
+ BackChainIdx = MFI->CreateFixedObject(8, -SystemZMC::CallFrameSize, false);
+ FI->setFramePointerSaveIndex(BackChainIdx);
+ }
+ SDValue BackChain = DAG.getFrameIndex(BackChainIdx, PtrVT);
+
+ // FIXME The frontend should detect this case.
+ if (Depth > 0) {
+ report_fatal_error("Unsupported stack frame traversal count");
+ }
+
+ return BackChain;
+}
+
+SDValue SystemZTargetLowering::lowerRETURNADDR(SDValue Op,
+ SelectionDAG &DAG) const {
+ MachineFunction &MF = DAG.getMachineFunction();
+ MachineFrameInfo *MFI = MF.getFrameInfo();
+ MFI->setReturnAddressIsTaken(true);
+
+ if (verifyReturnAddressArgumentIsConstant(Op, DAG))
+ return SDValue();
+
+ SDLoc DL(Op);
+ unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
+ EVT PtrVT = getPointerTy(DAG.getDataLayout());
+
+ // FIXME The frontend should detect this case.
+ if (Depth > 0) {
+ report_fatal_error("Unsupported stack frame traversal count");
+ }
+
+ // Return R14D, which has the return address. Mark it an implicit live-in.
+ unsigned LinkReg = MF.addLiveIn(SystemZ::R14D, &SystemZ::GR64BitRegClass);
+ return DAG.getCopyFromReg(DAG.getEntryNode(), DL, LinkReg, PtrVT);
+}
+
SDValue SystemZTargetLowering::lowerBITCAST(SDValue Op,
SelectionDAG &DAG) const {
SDLoc DL(Op);
@@ -4347,6 +4398,10 @@ SDValue SystemZTargetLowering::lowerShif
SDValue SystemZTargetLowering::LowerOperation(SDValue Op,
SelectionDAG &DAG) const {
switch (Op.getOpcode()) {
+ case ISD::FRAMEADDR:
+ return lowerFRAMEADDR(Op, DAG);
+ case ISD::RETURNADDR:
+ return lowerRETURNADDR(Op, DAG);
case ISD::BR_CC:
return lowerBR_CC(Op, DAG);
case ISD::SELECT_CC:
Modified: llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.h?rev=265291&r1=265290&r2=265291&view=diff
==============================================================================
--- llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.h (original)
+++ llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.h Mon Apr 4 07:44:55 2016
@@ -467,6 +467,8 @@ private:
SelectionDAG &DAG) const;
SDValue lowerJumpTable(JumpTableSDNode *JT, SelectionDAG &DAG) const;
SDValue lowerConstantPool(ConstantPoolSDNode *CP, SelectionDAG &DAG) const;
+ SDValue lowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const;
+ SDValue lowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerVASTART(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerVACOPY(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) const;
Modified: llvm/trunk/lib/Target/SystemZ/SystemZMachineFunctionInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/SystemZ/SystemZMachineFunctionInfo.h?rev=265291&r1=265290&r2=265291&view=diff
==============================================================================
--- llvm/trunk/lib/Target/SystemZ/SystemZMachineFunctionInfo.h (original)
+++ llvm/trunk/lib/Target/SystemZ/SystemZMachineFunctionInfo.h Mon Apr 4 07:44:55 2016
@@ -22,14 +22,15 @@ class SystemZMachineFunctionInfo : publi
unsigned VarArgsFirstFPR;
unsigned VarArgsFrameIndex;
unsigned RegSaveFrameIndex;
+ int FramePointerSaveIndex;
bool ManipulatesSP;
unsigned NumLocalDynamics;
public:
explicit SystemZMachineFunctionInfo(MachineFunction &MF)
: LowSavedGPR(0), HighSavedGPR(0), VarArgsFirstGPR(0), VarArgsFirstFPR(0),
- VarArgsFrameIndex(0), RegSaveFrameIndex(0), ManipulatesSP(false),
- NumLocalDynamics(0) {}
+ VarArgsFrameIndex(0), RegSaveFrameIndex(0), FramePointerSaveIndex(0),
+ ManipulatesSP(false), NumLocalDynamics(0) {}
// Get and set the first call-saved GPR that should be saved and restored
// by this function. This is 0 if no GPRs need to be saved or restored.
@@ -59,6 +60,10 @@ public:
unsigned getRegSaveFrameIndex() const { return RegSaveFrameIndex; }
void setRegSaveFrameIndex(unsigned FI) { RegSaveFrameIndex = FI; }
+ // Get and set the frame index of where the old frame pointer is stored.
+ int getFramePointerSaveIndex() const { return FramePointerSaveIndex; }
+ void setFramePointerSaveIndex(int Idx) { FramePointerSaveIndex = Idx; }
+
// Get and set whether the function directly manipulates the stack pointer,
// e.g. through STACKSAVE or STACKRESTORE.
bool getManipulatesSP() const { return ManipulatesSP; }
Added: llvm/trunk/test/CodeGen/SystemZ/frameaddr-01.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/SystemZ/frameaddr-01.ll?rev=265291&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/SystemZ/frameaddr-01.ll (added)
+++ llvm/trunk/test/CodeGen/SystemZ/frameaddr-01.ll Mon Apr 4 07:44:55 2016
@@ -0,0 +1,28 @@
+; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
+
+; The current function's frame address is the address of
+; the optional back chain slot.
+define i8* @fp0() nounwind {
+entry:
+; CHECK-LABEL: fp0:
+; CHECK: la %r2, 0(%r15)
+; CHECK: br %r14
+ %0 = tail call i8* @llvm.frameaddress(i32 0)
+ ret i8* %0
+}
+
+; Check that the frame address is correct in a presence
+; of a stack frame.
+define i8* @fp0f() nounwind {
+entry:
+; CHECK-LABEL: fp0f:
+; CHECK: aghi %r15, -168
+; CHECK: la %r2, 168(%r15)
+; CHECK: aghi %r15, 168
+; CHECK: br %r14
+ %0 = alloca i64, align 8
+ %1 = tail call i8* @llvm.frameaddress(i32 0)
+ ret i8* %1
+}
+
+declare i8* @llvm.frameaddress(i32) nounwind readnone
Added: llvm/trunk/test/CodeGen/SystemZ/ret-addr-01.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/SystemZ/ret-addr-01.ll?rev=265291&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/SystemZ/ret-addr-01.ll (added)
+++ llvm/trunk/test/CodeGen/SystemZ/ret-addr-01.ll Mon Apr 4 07:44:55 2016
@@ -0,0 +1,15 @@
+; Test support for the llvm.returnaddress intrinsic.
+;
+; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
+
+; The current function's return address is in the link register.
+define i8* @rt0() norecurse nounwind readnone {
+entry:
+; CHECK-LABEL: rt0:
+; CHECK: lgr %r2, %r14
+; CHECK: br %r14
+ %0 = tail call i8* @llvm.returnaddress(i32 0)
+ ret i8* %0
+}
+
+declare i8* @llvm.returnaddress(i32) nounwind readnone
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