Initial skeleton of Subzero.

src/IceGlobalContext.h

Index: src/IceGlobalContext.h
diff --git a/src/IceGlobalContext.h b/src/IceGlobalContext.h
new file mode 100644
index 0000000000000000000000000000000000000000..9224d899cf449281efb176836bece1af6fc5d166
--- /dev/null
+++ b/src/IceGlobalContext.h
@@ -0,0 +1,85 @@
+//===- subzero/src/IceGlobalContext.h - Global context defs -----*- C++ -*-===//
+//
+//                        The Subzero Code Generator
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares aspects of the compilation that persist across
+// multiple functions.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SUBZERO_SRC_ICEGLOBALCONTEXT_H
+#define SUBZERO_SRC_ICEGLOBALCONTEXT_H
+
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/Support/Allocator.h"
+#include "llvm/Support/raw_ostream.h"
+
+#include "IceDefs.h"
+#include "IceTypes.h"
+
+namespace Ice {
+
+// TODO: Accesses to all non-const fields of GlobalContext need to
+// be synchronized, especially the constant pool, the allocator, and
+// the output streams.
+class GlobalContext {
+public:
+  GlobalContext(llvm::raw_ostream *OsDump, llvm::raw_ostream *OsEmit,
+                VerboseMask Mask, IceString TestPrefix);
+  ~GlobalContext();
+
+  // Returns true if any of the specified options in the verbose mask
+  // are set.  If the argument is omitted, it checks if any verbose
+  // options at all are set.  IceV_Timing is treated specially, so
+  // that running with just IceV_Timing verbosity doesn't trigger an
+  // avalanche of extra output.
+  bool isVerbose(VerboseMask Mask = (IceV_All & ~IceV_Timing)) const {
+    return VMask & Mask;
+  }
+  void setVerbose(VerboseMask Mask) { VMask = Mask; }
+  void addVerbose(VerboseMask Mask) { VMask |= Mask; }
+  void subVerbose(VerboseMask Mask) { VMask &= ~Mask; }
+
+  Ostream &getStrDump() { return StrDump; }
+  Ostream &getStrEmit() { return StrEmit; }
+
+  // When emitting assembly, we allow a string to be prepended to
+  // names of translated functions.  This makes it easier to create an
+  // execution test against a reference translator like llc, with both
+  // translators using the same bitcode as input.
+  IceString getTestPrefix() const { return TestPrefix; }
+  IceString mangleName(const IceString &Name) const;
+
+  // Manage Constants.
+  // getConstant*() functions are not const because they might add
+  // something to the constant pool.
+  Constant *getConstantInt(Type Ty, uint64_t ConstantInt64);
+  Constant *getConstantFloat(float Value);
+  Constant *getConstantDouble(double Value);
+  // Returns a symbolic constant.
+  Constant *getConstantSym(Type Ty, int64_t Offset, const IceString &Name = "",
+                           bool SuppressMangling = false);
+
+  // Allocate data of type T using the global allocator.
+  template <typename T> T *allocate() { return Allocator.Allocate<T>(); }
+
+private:
+  Ostream StrDump; // Stream for dumping / diagnostics
+  Ostream StrEmit; // Stream for code emission
+
+  llvm::BumpPtrAllocator Allocator;
+  VerboseMask VMask;
+  llvm::OwningPtr<class ConstantPool> ConstPool;
+  const IceString TestPrefix;
+  GlobalContext(const GlobalContext &) LLVM_DELETED_FUNCTION;
+  GlobalContext &operator=(const GlobalContext &) LLVM_DELETED_FUNCTION;
+};
+
+} // end of namespace Ice
+
+#endif // SUBZERO_SRC_ICEGLOBALCONTEXT_H