Merge "Update prebuilt Clang to r353983." into p9.0HEADp9.0-backupp9.0

1 files changed, 102 insertions, 0 deletions

diff --git a/clang-r353983/include/llvm/MC/ConstantPools.h b/clang-r353983/include/llvm/MC/ConstantPools.h
new file mode 100644
index 00000000..2fe5ce25
--- /dev/null
+++ b/clang-r353983/include/llvm/MC/ConstantPools.h
@@ -0,0 +1,102 @@
+//===- ConstantPools.h - Keep track of assembler-generated ------*- 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 the ConstantPool and AssemblerConstantPools classes.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_CONSTANTPOOLS_H
+#define LLVM_MC_CONSTANTPOOLS_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/MapVector.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/SMLoc.h"
+#include <cstdint>
+#include <map>
+
+namespace llvm {
+
+class MCContext;
+class MCExpr;
+class MCSection;
+class MCStreamer;
+class MCSymbol;
+class MCSymbolRefExpr;
+
+struct ConstantPoolEntry {
+  ConstantPoolEntry(MCSymbol *L, const MCExpr *Val, unsigned Sz, SMLoc Loc_)
+    : Label(L), Value(Val), Size(Sz), Loc(Loc_) {}
+
+  MCSymbol *Label;
+  const MCExpr *Value;
+  unsigned Size;
+  SMLoc Loc;
+};
+
+// A class to keep track of assembler-generated constant pools that are use to
+// implement the ldr-pseudo.
+class ConstantPool {
+  using EntryVecTy = SmallVector<ConstantPoolEntry, 4>;
+  EntryVecTy Entries;
+  std::map<int64_t, const MCSymbolRefExpr *> CachedEntries;
+
+public:
+  // Initialize a new empty constant pool
+  ConstantPool() = default;
+
+  // Add a new entry to the constant pool in the next slot.
+  // \param Value is the new entry to put in the constant pool.
+  // \param Size is the size in bytes of the entry
+  //
+  // \returns a MCExpr that references the newly inserted value
+  const MCExpr *addEntry(const MCExpr *Value, MCContext &Context,
+                         unsigned Size, SMLoc Loc);
+
+  // Emit the contents of the constant pool using the provided streamer.
+  void emitEntries(MCStreamer &Streamer);
+
+  // Return true if the constant pool is empty
+  bool empty();
+
+  void clearCache();
+};
+
+class AssemblerConstantPools {
+  // Map type used to keep track of per-Section constant pools used by the
+  // ldr-pseudo opcode. The map associates a section to its constant pool. The
+  // constant pool is a vector of (label, value) pairs. When the ldr
+  // pseudo is parsed we insert a new (label, value) pair into the constant pool
+  // for the current section and add MCSymbolRefExpr to the new label as
+  // an opcode to the ldr. After we have parsed all the user input we
+  // output the (label, value) pairs in each constant pool at the end of the
+  // section.
+  //
+  // We use the MapVector for the map type to ensure stable iteration of
+  // the sections at the end of the parse. We need to iterate over the
+  // sections in a stable order to ensure that we have print the
+  // constant pools in a deterministic order when printing an assembly
+  // file.
+  using ConstantPoolMapTy = MapVector<MCSection *, ConstantPool>;
+  ConstantPoolMapTy ConstantPools;
+
+public:
+  void emitAll(MCStreamer &Streamer);
+  void emitForCurrentSection(MCStreamer &Streamer);
+  void clearCacheForCurrentSection(MCStreamer &Streamer);
+  const MCExpr *addEntry(MCStreamer &Streamer, const MCExpr *Expr,
+                         unsigned Size, SMLoc Loc);
+
+private:
+  ConstantPool *getConstantPool(MCSection *Section);
+  ConstantPool &getOrCreateConstantPool(MCSection *Section);
+};
+
+} // end namespace llvm
+
+#endif // LLVM_MC_CONSTANTPOOLS_H