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authorvitalyisaev <vitalyisaev@yandex-team.com>2023-06-29 10:00:50 +0300
committervitalyisaev <vitalyisaev@yandex-team.com>2023-06-29 10:00:50 +0300
commit6ffe9e53658409f212834330e13564e4952558f6 (patch)
tree85b1e00183517648b228aafa7c8fb07f5276f419 /contrib/libs/llvm14/lib/CodeGen/SafeStackLayout.cpp
parent726057070f9c5a91fc10fde0d5024913d10f1ab9 (diff)
downloadydb-6ffe9e53658409f212834330e13564e4952558f6.tar.gz
YQ Connector: support managed ClickHouse
Со стороны dqrun можно обратиться к инстансу коннектора, который работает на streaming стенде, и извлечь данные из облачного CH.
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diff --git a/contrib/libs/llvm14/lib/CodeGen/SafeStackLayout.cpp b/contrib/libs/llvm14/lib/CodeGen/SafeStackLayout.cpp
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+//===- SafeStackLayout.cpp - SafeStack frame layout -----------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "SafeStackLayout.h"
+#include "llvm/IR/Value.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/MathExtras.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+#include <cassert>
+
+using namespace llvm;
+using namespace llvm::safestack;
+
+#define DEBUG_TYPE "safestacklayout"
+
+static cl::opt<bool> ClLayout("safe-stack-layout",
+ cl::desc("enable safe stack layout"), cl::Hidden,
+ cl::init(true));
+
+LLVM_DUMP_METHOD void StackLayout::print(raw_ostream &OS) {
+ OS << "Stack regions:\n";
+ for (unsigned i = 0; i < Regions.size(); ++i) {
+ OS << " " << i << ": [" << Regions[i].Start << ", " << Regions[i].End
+ << "), range " << Regions[i].Range << "\n";
+ }
+ OS << "Stack objects:\n";
+ for (auto &IT : ObjectOffsets) {
+ OS << " at " << IT.getSecond() << ": " << *IT.getFirst() << "\n";
+ }
+}
+
+void StackLayout::addObject(const Value *V, unsigned Size, Align Alignment,
+ const StackLifetime::LiveRange &Range) {
+ StackObjects.push_back({V, Size, Alignment, Range});
+ ObjectAlignments[V] = Alignment;
+ MaxAlignment = std::max(MaxAlignment, Alignment);
+}
+
+static unsigned AdjustStackOffset(unsigned Offset, unsigned Size,
+ Align Alignment) {
+ return alignTo(Offset + Size, Alignment) - Size;
+}
+
+void StackLayout::layoutObject(StackObject &Obj) {
+ if (!ClLayout) {
+ // If layout is disabled, just grab the next aligned address.
+ // This effectively disables stack coloring as well.
+ unsigned LastRegionEnd = Regions.empty() ? 0 : Regions.back().End;
+ unsigned Start = AdjustStackOffset(LastRegionEnd, Obj.Size, Obj.Alignment);
+ unsigned End = Start + Obj.Size;
+ Regions.emplace_back(Start, End, Obj.Range);
+ ObjectOffsets[Obj.Handle] = End;
+ return;
+ }
+
+ LLVM_DEBUG(dbgs() << "Layout: size " << Obj.Size << ", align "
+ << Obj.Alignment.value() << ", range " << Obj.Range
+ << "\n");
+ assert(Obj.Alignment <= MaxAlignment);
+ unsigned Start = AdjustStackOffset(0, Obj.Size, Obj.Alignment);
+ unsigned End = Start + Obj.Size;
+ LLVM_DEBUG(dbgs() << " First candidate: " << Start << " .. " << End << "\n");
+ for (const StackRegion &R : Regions) {
+ LLVM_DEBUG(dbgs() << " Examining region: " << R.Start << " .. " << R.End
+ << ", range " << R.Range << "\n");
+ assert(End >= R.Start);
+ if (Start >= R.End) {
+ LLVM_DEBUG(dbgs() << " Does not intersect, skip.\n");
+ continue;
+ }
+ if (Obj.Range.overlaps(R.Range)) {
+ // Find the next appropriate location.
+ Start = AdjustStackOffset(R.End, Obj.Size, Obj.Alignment);
+ End = Start + Obj.Size;
+ LLVM_DEBUG(dbgs() << " Overlaps. Next candidate: " << Start << " .. "
+ << End << "\n");
+ continue;
+ }
+ if (End <= R.End) {
+ LLVM_DEBUG(dbgs() << " Reusing region(s).\n");
+ break;
+ }
+ }
+
+ unsigned LastRegionEnd = Regions.empty() ? 0 : Regions.back().End;
+ if (End > LastRegionEnd) {
+ // Insert a new region at the end. Maybe two.
+ if (Start > LastRegionEnd) {
+ LLVM_DEBUG(dbgs() << " Creating gap region: " << LastRegionEnd << " .. "
+ << Start << "\n");
+ Regions.emplace_back(LastRegionEnd, Start, StackLifetime::LiveRange(0));
+ LastRegionEnd = Start;
+ }
+ LLVM_DEBUG(dbgs() << " Creating new region: " << LastRegionEnd << " .. "
+ << End << ", range " << Obj.Range << "\n");
+ Regions.emplace_back(LastRegionEnd, End, Obj.Range);
+ LastRegionEnd = End;
+ }
+
+ // Split starting and ending regions if necessary.
+ for (unsigned i = 0; i < Regions.size(); ++i) {
+ StackRegion &R = Regions[i];
+ if (Start > R.Start && Start < R.End) {
+ StackRegion R0 = R;
+ R.Start = R0.End = Start;
+ Regions.insert(&R, R0);
+ continue;
+ }
+ if (End > R.Start && End < R.End) {
+ StackRegion R0 = R;
+ R0.End = R.Start = End;
+ Regions.insert(&R, R0);
+ break;
+ }
+ }
+
+ // Update live ranges for all affected regions.
+ for (StackRegion &R : Regions) {
+ if (Start < R.End && End > R.Start)
+ R.Range.join(Obj.Range);
+ if (End <= R.End)
+ break;
+ }
+
+ ObjectOffsets[Obj.Handle] = End;
+}
+
+void StackLayout::computeLayout() {
+ // Simple greedy algorithm.
+ // If this is replaced with something smarter, it must preserve the property
+ // that the first object is always at the offset 0 in the stack frame (for
+ // StackProtectorSlot), or handle stack protector in some other way.
+
+ // Sort objects by size (largest first) to reduce fragmentation.
+ if (StackObjects.size() > 2)
+ llvm::stable_sort(drop_begin(StackObjects),
+ [](const StackObject &a, const StackObject &b) {
+ return a.Size > b.Size;
+ });
+
+ for (auto &Obj : StackObjects)
+ layoutObject(Obj);
+
+ LLVM_DEBUG(print(dbgs()));
+}