Optmize call convention in SBFv2

llvm/lib/Target/SBF/CMakeLists.txt

@@ -34,6 +34,7 @@ add_llvm_target(SBFCodeGen
   SBFMIChecking.cpp
   SBFMISimplifyPatchable.cpp
   BTFDebug.cpp
+  SBFFunctionInfo.cpp
 
   LINK_COMPONENTS
   Analysis

llvm/lib/Target/SBF/SBFFunctionInfo.cpp

@@ -0,0 +1,28 @@
+//=- SBFFunctionInfo.cpp - SBF Machine Function Info ---------=//
+
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file implements SBF-specific per-machine-function
+/// information.
+///
+//===----------------------------------------------------------------------===//
+
+#include "SBFFunctionInfo.h"
+
+namespace llvm {
+
+void SBFFunctionInfo::storeFrameIndexArgument(int FI) {
+  frameIndexes.insert(FI);
+}
+
+bool SBFFunctionInfo::containsFrameIndex(int FI) const {
+  return frameIndexes.find(FI) != frameIndexes.end();
+}
+
+} // namespace llvm

llvm/lib/Target/SBF/SBFFunctionInfo.h

@@ -0,0 +1,32 @@
+//=- SBFFunctionInfo.h - SBF machine function info -*- C++ -*-=//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares SBF-specific per-machine-function information.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SBFFUNCTIONINFO_H
+#define LLVM_SBFFUNCTIONINFO_H
+
+#include "SBFSubtarget.h"
+#include <unordered_set>
+
+namespace llvm {
+
+class SBFFunctionInfo final : public MachineFunctionInfo {
+  std::unordered_set<int> frameIndexes;
+
+public:
+  SBFFunctionInfo(const Function &F, const SBFSubtarget *STI){};
+
+  void storeFrameIndexArgument(int FI);
+  bool containsFrameIndex(int FI) const;
+};
+} // namespace llvm
+
+#endif // LLVM_SBFFUNCTIONINFO_H

llvm/lib/Target/SBF/SBFISelLowering.cpp

@@ -11,6 +11,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "SBFFunctionInfo.h"
 #include "SBFRegisterInfo.h"
 #include "SBFSubtarget.h"
 #include "llvm/CodeGen/CallingConvLower.h"
@@ -413,8 +414,15 @@ SDValue SBFTargetLowering::LowerFormalArguments(
   SmallVector<CCValAssign, 16> ArgLocs;
   CCState CCInfo(CallConv, IsVarArg, MF, ArgLocs, *DAG.getContext());
   if (Subtarget->isSolana() && Ins.size() > MaxArgs) {
-    // Pass args 1-4 via registers, remaining args via stack, referenced via SBF::R5
-    CCInfo.AnalyzeFormalArguments(Ins, getHasAlu32() ? CC_SBF32_X : CC_SBF64_X);
+    if (Subtarget->getEnableNewCallConvention()) {
+      // Pass args 1-5 via registers, remaining args via stack.
+      CCInfo.AnalyzeFormalArguments(Ins, getHasAlu32() ? CC_SBF32 : CC_SBF64);
+    } else {
+      // Pass args 1-4 via registers, remaining args via stack, referenced via
+      // SBF::R5
+      CCInfo.AnalyzeFormalArguments(Ins,
+                                    getHasAlu32() ? CC_SBF32_X : CC_SBF64_X);
+    }
   } else {
     // Pass all args via registers
     CCInfo.AnalyzeFormalArguments(Ins, getHasAlu32() ? CC_SBF32 : CC_SBF64);
@@ -461,20 +469,37 @@ SDValue SBFTargetLowering::LowerFormalArguments(
       EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy(DAG.getDataLayout());
       EVT LocVT = VA.getLocVT();
 
-      unsigned Offset;
-      if (Subtarget->getHasDynamicFrames()) {
-        // In SBFv2, the arguments are stored on the start of the frame.
-        Offset = VA.getLocMemOffset() + PtrVT.getFixedSizeInBits() / 8;
+      SDValue SDV;
+      if (Subtarget->getEnableNewCallConvention()) {
+        // In the new convention, arguments are in at the start
+        // of the callee frame
+        uint64_t Size = PtrVT.getFixedSizeInBits() / 8;
+        int64_t Offset = -static_cast<int64_t>(VA.getLocMemOffset() + Size);
+        int FrameIndex =
+            MF.getFrameInfo().CreateFixedObject(Size, Offset, false);
+        SDValue DstAddr = DAG.getFrameIndex(FrameIndex, PtrVT);
+        MachinePointerInfo DstInfo =
+            MachinePointerInfo::getFixedStack(MF, FrameIndex, Offset);
+        SDV = DAG.getLoad(LocVT, DL, Chain, DstAddr, DstInfo);
       } else {
-        Offset = SBFRegisterInfo::FrameLength - VA.getLocMemOffset();
+        unsigned Offset;
+        if (Subtarget->getHasDynamicFrames()) {
+          // In the old convention, the arguments are stored on
+          // the start of caller the frame.
+          Offset = VA.getLocMemOffset() + PtrVT.getFixedSizeInBits() / 8;
+        } else {
+          Offset = SBFRegisterInfo::FrameLength - VA.getLocMemOffset();
+        }
+
+        // Arguments relative to SBF::R5
+        unsigned reg = MF.addLiveIn(SBF::R5, &SBF::GPRRegClass);
+        SDValue Const = DAG.getConstant(Offset, DL, MVT::i64);
+        SDV = DAG.getCopyFromReg(Chain, DL, reg,
+                                 getPointerTy(MF.getDataLayout()));
+        SDV = DAG.getNode(ISD::SUB, DL, PtrVT, SDV, Const);
+        SDV = DAG.getLoad(LocVT, DL, Chain, SDV, MachinePointerInfo());
       }
 
-      // Arguments relative to SBF::R5
-      unsigned reg = MF.addLiveIn(SBF::R5, &SBF::GPRRegClass);
-      SDValue Const = DAG.getConstant(Offset, DL, MVT::i64);
-      SDValue SDV = DAG.getCopyFromReg(Chain, DL, reg, getPointerTy(MF.getDataLayout()));
-      SDV = DAG.getNode(ISD::SUB, DL, PtrVT, SDV, Const);
-      SDV = DAG.getLoad(LocVT, DL, Chain, SDV, MachinePointerInfo());
       InVals.push_back(SDV);
     } else {
       fail(DL, DAG, "defined with too many args");
@@ -524,8 +549,14 @@ SDValue SBFTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
   SmallVector<CCValAssign, 16> ArgLocs;
   CCState CCInfo(CallConv, IsVarArg, MF, ArgLocs, *DAG.getContext());
   if (Subtarget->isSolana() && Outs.size() > MaxArgs) {
-    // Pass args 1-4 via registers, remaining args via stack, referenced via SBF::R5
-    CCInfo.AnalyzeCallOperands(Outs, getHasAlu32() ? CC_SBF32_X : CC_SBF64_X);
+    if (Subtarget->getEnableNewCallConvention()) {
+      // Pass args 1-5 via registers, remaining args via stack
+      CCInfo.AnalyzeCallOperands(Outs, getHasAlu32() ? CC_SBF32 : CC_SBF64);
+    } else {
+      // Pass args 1-4 via registers, remaining args via stack, referenced via
+      // SBF::R5
+      CCInfo.AnalyzeCallOperands(Outs, getHasAlu32() ? CC_SBF32_X : CC_SBF64_X);
+    }
   } else {
     // Pass all args via registers
     CCInfo.AnalyzeCallOperands(Outs, getHasAlu32() ? CC_SBF32 : CC_SBF64);
@@ -595,6 +626,7 @@ SDValue SBFTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
                                           Subtarget->getRegisterInfo()->getFrameRegister(MF),
                                           getPointerTy(MF.getDataLayout()));
 
+    SBFFunctionInfo * SBFFuncInfo = MF.getInfo<SBFFunctionInfo>();
     // Stack arguments have to be walked in reverse order by inserting
     // chained stores, this ensures their order is not changed by the scheduler
     // and that the push instruction sequence generated is correct, otherwise they
@@ -610,13 +642,19 @@ SDValue SBFTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
       SDValue DstAddr;
       MachinePointerInfo DstInfo;
       if (Subtarget->getHasDynamicFrames()) {
-        // When dynamic frames are enabled, the frame size is only calculated
-        // after lowering instructions, so we must place arguments at the start
-        // of the frame.
-        int64_t Offset = -static_cast<int64_t>(VA.getLocMemOffset() +
-                                               PtrVT.getFixedSizeInBits() / 8);
+        // In the new call convention, arguments are stored in the callee frame
+        // The positive offset signals that the variable does not occupy space
+        // in the caller frame.
+        int64_t Offset = static_cast<int64_t>(VA.getLocMemOffset() +
+                                              PtrVT.getFixedSizeInBits() / 8);
+        if (!Subtarget->getEnableNewCallConvention())
+          // In the old call convention, we place argument at the start of the
+          // frame in a fixed stack offset.
+          Offset = -Offset;
+
         int FrameIndex = MF.getFrameInfo().CreateFixedObject(
             VA.getLocVT().getFixedSizeInBits() / 8, Offset, false);
+        SBFFuncInfo->storeFrameIndexArgument(FrameIndex);
         DstAddr = DAG.getFrameIndex(FrameIndex, PtrVT);
         DstInfo = MachinePointerInfo::getFixedStack(MF, FrameIndex, Offset);
       } else {

llvm/lib/Target/SBF/SBFRegisterInfo.cpp

@@ -10,8 +10,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "SBFFunctionInfo.h"
 #include "SBFRegisterInfo.h"
-#include "SBF.h"
 #include "SBFSubtarget.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineFunction.h"
@@ -102,7 +102,7 @@ bool SBFRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
   const TargetInstrInfo &TII = *MF.getSubtarget().getInstrInfo();
 
   if (MI.getOpcode() == SBF::MOV_rr) {
-    int Offset = MF.getFrameInfo().getObjectOffset(FrameIndex);
+    int Offset = resolveInternalFrameIndex(MF, FrameIndex, std::nullopt);
 
     if (!MF.getSubtarget<SBFSubtarget>().getHasDynamicFrames()) {
       WarnSize(Offset, MF, DL);
@@ -115,8 +115,9 @@ bool SBFRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
     return false;
   }
 
-  int Offset = MF.getFrameInfo().getObjectOffset(FrameIndex) +
-               MI.getOperand(i + 1).getImm();
+  int Offset =
+      resolveInternalFrameIndex(MF, FrameIndex, MI.getOperand(i + 1).getImm());
+
 
   if (!isInt<32>(Offset))
     llvm_unreachable("bug in frame offset");
@@ -146,6 +147,22 @@ bool SBFRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
   return false;
 }
 
+int SBFRegisterInfo::resolveInternalFrameIndex(
+    const llvm::MachineFunction &MF, int FI, std::optional<int64_t> Imm) const {
+  const MachineFrameInfo &MFI = MF.getFrameInfo();
+  const SBFFunctionInfo *SBFFuncInfo = MF.getInfo<SBFFunctionInfo>();
+  int Offset = MFI.getObjectOffset(FI);
+  if (MF.getSubtarget<SBFSubtarget>().getEnableNewCallConvention() &&
+      SBFFuncInfo->containsFrameIndex(FI)) {
+    uint64_t StackSize = MFI.getStackSize();
+    Offset = -static_cast<int>(StackSize) - Offset;
+  } else if (Imm.has_value()) {
+    Offset += Imm.value();
+  }
+
+  return Offset;
+}
+
 Register SBFRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
   return SBF::R10;
 }

llvm/lib/Target/SBF/SBFRegisterInfo.h

@@ -14,6 +14,7 @@
 #define LLVM_LIB_TARGET_SBF_SBFREGISTERINFO_H
 
 #include "llvm/CodeGen/TargetRegisterInfo.h"
+#include <optional>
 
 #define GET_REGINFO_HEADER
 #include "SBFGenRegisterInfo.inc"
@@ -34,6 +35,9 @@ struct SBFRegisterInfo : public SBFGenRegisterInfo {
                            RegScavenger *RS = nullptr) const override;
 
   Register getFrameRegister(const MachineFunction &MF) const override;
+
+  int resolveInternalFrameIndex(const MachineFunction &MF, int FI,
+                                std::optional<int64_t> Imm) const;
 };
 }
 

llvm/lib/Target/SBF/SBFSubtarget.cpp

@@ -47,6 +47,7 @@ void SBFSubtarget::initializeEnvironment(const Triple &TT) {
   NoLddw = false;
   CallxRegSrc = false;
   HasPqrClass = false;
+  NewCallConvention = false;
 }
 
 void SBFSubtarget::initSubtargetFeatures(StringRef CPU, StringRef FS) {

llvm/lib/Target/SBF/SBFSubtarget.h

@@ -80,6 +80,9 @@ class SBFSubtarget : public SBFGenSubtargetInfo {
   // Whether we have the PQR instruction class
   bool HasPqrClass;
 
+  // Whether to use the new call convention in SBFv2
+  bool NewCallConvention;
+
 public:
   // This constructor initializes the data members to match that
   // of the specified triple.
@@ -102,7 +105,9 @@ class SBFSubtarget : public SBFGenSubtargetInfo {
   bool getNoLddw() const { return NoLddw; }
   bool getCallXRegSrc() const { return CallxRegSrc; }
   bool getHasPqrClass() const { return HasPqrClass; }
-
+  bool getEnableNewCallConvention() const {
+    return HasDynamicFrames && NewCallConvention;
+  }
   const SBFInstrInfo *getInstrInfo() const override { return &InstrInfo; }
   const SBFFrameLowering *getFrameLowering() const override {
     return &FrameLowering;

llvm/lib/Target/SBF/SBFTargetFeatures.td

@@ -46,6 +46,9 @@ def FeatureCallxRegSrc : SubtargetFeature<"callx-reg-src", "CallxRegSrc", "true"
 def FeaturePqrInstr : SubtargetFeature<"pqr-instr", "HasPqrClass", "true",
                                     "Enable the PQR instruction class">;
 
+def FeatureCallConv : SubtargetFeature<"new-call-conv", "NewCallConvention", "true",
+                                    "Enable new call convetion for SBFv2">;
+
 class Proc<string Name, list<SubtargetFeature> Features>
  : Processor<Name, NoItineraries, Features>;
 
@@ -55,4 +58,4 @@ def : Proc<"v2", []>;
 def : Proc<"v3", [ALU32]>;
 def : Proc<"sbfv2", [FeatureSolana, FeatureDynamicFrames, FeatureRelocAbs64, FeatureStaticSyscalls,
                         FeatureDisableNeg, FeatureReverseSubImm, FeatureDisableLddw, FeatureCallxRegSrc,
-                          FeaturePqrInstr]>;
+                          FeaturePqrInstr, FeatureCallConv]>;

llvm/lib/Target/SBF/SBFTargetMachine.cpp

@@ -10,9 +10,10 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "SBFTargetMachine.h"
 #include "SBF.h"
+#include "SBFTargetMachine.h"
 #include "SBFTargetTransformInfo.h"
+#include "SBFFunctionInfo.h"
 #include "MCTargetDesc/SBFMCAsmInfo.h"
 #include "TargetInfo/SBFTargetInfo.h"
 #include "llvm/CodeGen/Passes.h"
@@ -134,6 +135,13 @@ SBFTargetMachine::getTargetTransformInfo(const Function &F) const {
   return TargetTransformInfo(SBFTTIImpl(this, F));
 }
 
+MachineFunctionInfo *SBFTargetMachine::createMachineFunctionInfo(
+    llvm::BumpPtrAllocator &Allocator, const llvm::Function &F,
+    const llvm::TargetSubtargetInfo *STI) const {
+  return SBFFunctionInfo::create<SBFFunctionInfo>(
+      Allocator, F, static_cast<const SBFSubtarget *>(STI));
+}
+
 // Install an instruction selector pass using
 // the ISelDag to gen SBF code.
 bool SBFPassConfig::addInstSelector() {

llvm/lib/Target/SBF/SBFTargetMachine.h

@@ -42,6 +42,10 @@ class SBFTargetMachine : public LLVMTargetMachine {
   }
 
   void registerPassBuilderCallbacks(PassBuilder &PB) override;
+
+  MachineFunctionInfo *
+  createMachineFunctionInfo(BumpPtrAllocator &Allocator, const Function &F,
+                            const TargetSubtargetInfo *STI) const override;
 };
 }