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diff --git a/include/llvm/MC/ConstantPools.h b/include/llvm/MC/ConstantPools.h
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+//===- ConstantPool.h - Keep track of assembler-generated ------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares the ConstantPool and AssemblerConstantPools classes.
+//
+//===----------------------------------------------------------------------===//
+
+
+#ifndef LLVM_MC_CONSTANTPOOL_H
+#define LLVM_MC_CONSTANTPOOL_H
+
+#include "llvm/ADT/SmallVector.h"
+namespace llvm {
+class MCContext;
+class MCExpr;
+class MCSection;
+class MCStreamer;
+class MCSymbol;
+// A class to keep track of assembler-generated constant pools that are use to
+// implement the ldr-pseudo.
+class ConstantPool {
+ typedef SmallVector<std::pair<MCSymbol *, const MCExpr *>, 4> EntryVecTy;
+ EntryVecTy Entries;
+
+public:
+ // Initialize a new empty constant pool
+ ConstantPool() {}
+
+ // Add a new entry to the constant pool in the next slot.
+ // \param Value is the new entry to put in the constant pool.
+ //
+ // \returns a MCExpr that references the newly inserted value
+ const MCExpr *addEntry(const MCExpr *Value, MCContext &Context);
+
+ // 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();
+};
+
+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.
+ typedef MapVector<const MCSection *, ConstantPool> ConstantPoolMapTy;
+ ConstantPoolMapTy ConstantPools;
+
+public:
+ AssemblerConstantPools() {}
+ ~AssemblerConstantPools() {}
+
+ void emitAll(MCStreamer &Streamer);
+ void emitForCurrentSection(MCStreamer &Streamer);
+ const MCExpr *addEntry(MCStreamer &Streamer, const MCExpr *Expr);
+
+private:
+ ConstantPool *getConstantPool(const MCSection *Section);
+ ConstantPool &getOrCreateConstantPool(const MCSection *Section);
+};
+} // end namespace llvm
+
+#endif