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diff --git a/contrib/llvm-project/llvm/lib/CodeGen/StackFrameLayoutAnalysisPass.cpp b/contrib/llvm-project/llvm/lib/CodeGen/StackFrameLayoutAnalysisPass.cpp
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+++ b/contrib/llvm-project/llvm/lib/CodeGen/StackFrameLayoutAnalysisPass.cpp
@@ -0,0 +1,253 @@
+//===-- StackFrameLayoutAnalysisPass.cpp
+//------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// StackFrameLayoutAnalysisPass implementation. Outputs information about the
+// layout of the stack frame, using the remarks interface. On the CLI it prints
+// a textual representation of the stack frame. When possible it prints the
+// values that occupy a stack slot using any available debug information. Since
+// output is remarks based, it is also available in a machine readable file
+// format, such as YAML.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/SetVector.h"
+#include "llvm/Analysis/OptimizationRemarkEmitter.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineOptimizationRemarkEmitter.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/CodeGen/SlotIndexes.h"
+#include "llvm/CodeGen/StackProtector.h"
+#include "llvm/CodeGen/TargetFrameLowering.h"
+#include "llvm/CodeGen/TargetSubtargetInfo.h"
+#include "llvm/IR/DebugInfoMetadata.h"
+#include "llvm/IR/PrintPasses.h"
+#include "llvm/InitializePasses.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/FormatVariadic.h"
+#include "llvm/Support/raw_ostream.h"
+
+#include <sstream>
+
+using namespace llvm;
+
+#define DEBUG_TYPE "stack-frame-layout"
+
+namespace {
+
+/// StackFrameLayoutAnalysisPass - This is a pass to dump the stack frame of a
+/// MachineFunction.
+///
+struct StackFrameLayoutAnalysisPass : public MachineFunctionPass {
+  using SlotDbgMap = SmallDenseMap<int, SetVector<const DILocalVariable *>>;
+  static char ID;
+
+  enum SlotType {
+    Spill,          // a Spill slot
+    StackProtector, // Stack Protector slot
+    Variable,       // a slot used to store a local data (could be a tmp)
+    Invalid         // It's an error for a slot to have this type
+  };
+
+  struct SlotData {
+    int Slot;
+    int Size;
+    int Align;
+    int Offset;
+    SlotType SlotTy;
+
+    SlotData(const MachineFrameInfo &MFI, const int ValOffset, const int Idx)
+        : Slot(Idx), Size(MFI.getObjectSize(Idx)),
+          Align(MFI.getObjectAlign(Idx).value()),
+          Offset(MFI.getObjectOffset(Idx) - ValOffset), SlotTy(Invalid) {
+      if (MFI.isSpillSlotObjectIndex(Idx))
+        SlotTy = SlotType::Spill;
+      else if (Idx == MFI.getStackProtectorIndex())
+        SlotTy = SlotType::StackProtector;
+      else
+        SlotTy = SlotType::Variable;
+    }
+
+    // we use this to sort in reverse order, so that the layout is displayed
+    // correctly
+    bool operator<(const SlotData &Rhs) const { return Offset > Rhs.Offset; }
+  };
+
+  StackFrameLayoutAnalysisPass() : MachineFunctionPass(ID) {}
+
+  StringRef getPassName() const override {
+    return "Stack Frame Layout Analysis";
+  }
+
+  void getAnalysisUsage(AnalysisUsage &AU) const override {
+    AU.setPreservesAll();
+    MachineFunctionPass::getAnalysisUsage(AU);
+    AU.addRequired<MachineOptimizationRemarkEmitterPass>();
+  }
+
+  bool runOnMachineFunction(MachineFunction &MF) override {
+    // TODO: We should implement a similar filter for remarks:
+    //   -Rpass-func-filter=<regex>
+    if (!isFunctionInPrintList(MF.getName()))
+      return false;
+
+    LLVMContext &Ctx = MF.getFunction().getContext();
+    if (!Ctx.getDiagHandlerPtr()->isAnalysisRemarkEnabled(DEBUG_TYPE))
+      return false;
+
+    MachineOptimizationRemarkAnalysis Rem(DEBUG_TYPE, "StackLayout",
+                                          MF.getFunction().getSubprogram(),
+                                          &MF.front());
+    Rem << ("\nFunction: " + MF.getName()).str();
+    emitStackFrameLayoutRemarks(MF, Rem);
+    getAnalysis<MachineOptimizationRemarkEmitterPass>().getORE().emit(Rem);
+    return false;
+  }
+
+  std::string getTypeString(SlotType Ty) {
+    switch (Ty) {
+    case SlotType::Spill:
+      return "Spill";
+    case SlotType::StackProtector:
+      return "Protector";
+    case SlotType::Variable:
+      return "Variable";
+    default:
+      llvm_unreachable("bad slot type for stack layout");
+    }
+  }
+
+  void emitStackSlotRemark(const MachineFunction &MF, const SlotData &D,
+                           MachineOptimizationRemarkAnalysis &Rem) {
+    // To make it easy to understand the stack layout from the CLI, we want to
+    // print each slot like the following:
+    //
+    //   Offset: [SP+8], Type: Spill, Align: 8, Size: 16
+    //       foo @ /path/to/file.c:25
+    //       bar @ /path/to/file.c:35
+    //
+    // Which prints the size, alignment, and offset from the SP at function
+    // entry.
+    //
+    // But we also want the machine readable remarks data to be nicely
+    // organized. So we print some additional data as strings for the CLI
+    // output, but maintain more structured data for the YAML.
+    //
+    // For example we store the Offset in YAML as:
+    //    ...
+    //    - Offset: -8
+    //
+    // But we print it to the CLI as
+    //   Offset: [SP-8]
+
+    // Negative offsets will print a leading `-`, so only add `+`
+    std::string Prefix =
+        formatv("\nOffset: [SP{0}", (D.Offset < 0) ? "" : "+").str();
+    Rem << Prefix << ore::NV("Offset", D.Offset)
+        << "], Type: " << ore::NV("Type", getTypeString(D.SlotTy))
+        << ", Align: " << ore::NV("Align", D.Align)
+        << ", Size: " << ore::NV("Size", D.Size);
+  }
+
+  void emitSourceLocRemark(const MachineFunction &MF, const DILocalVariable *N,
+                           MachineOptimizationRemarkAnalysis &Rem) {
+    std::string Loc =
+        formatv("{0} @ {1}:{2}", N->getName(), N->getFilename(), N->getLine())
+            .str();
+    Rem << "\n    " << ore::NV("DataLoc", Loc);
+  }
+
+  void emitStackFrameLayoutRemarks(MachineFunction &MF,
+                                   MachineOptimizationRemarkAnalysis &Rem) {
+    const MachineFrameInfo &MFI = MF.getFrameInfo();
+    if (!MFI.hasStackObjects())
+      return;
+
+    // ValOffset is the offset to the local area from the SP at function entry.
+    // To display the true offset from SP, we need to subtract ValOffset from
+    // MFI's ObjectOffset.
+    const TargetFrameLowering *FI = MF.getSubtarget().getFrameLowering();
+    const int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0);
+
+    LLVM_DEBUG(dbgs() << "getStackProtectorIndex =="
+                      << MFI.getStackProtectorIndex() << "\n");
+
+    std::vector<SlotData> SlotInfo;
+
+    const unsigned int NumObj = MFI.getNumObjects();
+    SlotInfo.reserve(NumObj);
+    // initialize slot info
+    for (int Idx = MFI.getObjectIndexBegin(), EndIdx = MFI.getObjectIndexEnd();
+         Idx != EndIdx; ++Idx) {
+      if (MFI.isDeadObjectIndex(Idx))
+        continue;
+      SlotInfo.emplace_back(MFI, ValOffset, Idx);
+    }
+
+    // sort the ordering, to match the actual layout in memory
+    llvm::sort(SlotInfo);
+
+    SlotDbgMap SlotMap = genSlotDbgMapping(MF);
+
+    for (const SlotData &Info : SlotInfo) {
+      emitStackSlotRemark(MF, Info, Rem);
+      for (const DILocalVariable *N : SlotMap[Info.Slot])
+        emitSourceLocRemark(MF, N, Rem);
+    }
+  }
+
+  // We need to generate a mapping of slots to the values that are stored to
+  // them. This information is lost by the time we need to print out the frame,
+  // so we reconstruct it here by walking the CFG, and generating the mapping.
+  SlotDbgMap genSlotDbgMapping(MachineFunction &MF) {
+    SlotDbgMap SlotDebugMap;
+
+    // add variables to the map
+    for (MachineFunction::VariableDbgInfo &DI : MF.getVariableDbgInfo())
+      SlotDebugMap[DI.Slot].insert(DI.Var);
+
+    // Then add all the spills that have debug data
+    for (MachineBasicBlock &MBB : MF) {
+      for (MachineInstr &MI : MBB) {
+        for (MachineMemOperand *MO : MI.memoperands()) {
+          if (!MO->isStore())
+            continue;
+          auto *FI = dyn_cast_or_null<FixedStackPseudoSourceValue>(
+              MO->getPseudoValue());
+          if (!FI)
+            continue;
+          int FrameIdx = FI->getFrameIndex();
+          SmallVector<MachineInstr *> Dbg;
+          MI.collectDebugValues(Dbg);
+
+          for (MachineInstr *MI : Dbg)
+            SlotDebugMap[FrameIdx].insert(MI->getDebugVariable());
+        }
+      }
+    }
+
+    return SlotDebugMap;
+  }
+};
+
+char StackFrameLayoutAnalysisPass::ID = 0;
+} // namespace
+
+char &llvm::StackFrameLayoutAnalysisPassID = StackFrameLayoutAnalysisPass::ID;
+INITIALIZE_PASS(StackFrameLayoutAnalysisPass, "stack-frame-layout",
+                "Stack Frame Layout", false, false)
+
+namespace llvm {
+/// Returns a newly-created StackFrameLayout pass.
+MachineFunctionPass *createStackFrameLayoutAnalysisPass() {
+  return new StackFrameLayoutAnalysisPass();
+}
+
+} // namespace llvm