Don't #include MemoryBuffer.h from Host.h.

It turns out this #include isn't used from Host.h anyway,
but by having it it causes circular include dependencies.
This issues only surfaced while I was working on a separate
patch, so I'm submitting this first so that it's independent
of the other, unrelated patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318489 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/ADT/StringExtras.h

@@ -17,6 +17,7 @@
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/Twine.h"
 #include <cassert>
 #include <cstddef>
 #include <cstdint>

include/llvm/DebugInfo/PDB/Native/NativeSession.h

@@ -22,6 +22,7 @@
 #include "llvm/Support/Error.h"
 
 namespace llvm {
+class MemoryBuffer;
 namespace pdb {
 class PDBFile;
 

include/llvm/MC/MCFragment.h

@@ -17,6 +17,7 @@
 #include "llvm/ADT/ilist_node.h"
 #include "llvm/MC/MCFixup.h"
 #include "llvm/MC/MCInst.h"
+#include "llvm/Support/Casting.h"
 #include "llvm/Support/SMLoc.h"
 #include <cstdint>
 #include <utility>

include/llvm/Support/CodeGenCoverage.h

@@ -17,6 +17,7 @@
 
 namespace llvm {
 class LLVMContext;
+class MemoryBuffer;
 
 class CodeGenCoverage {
 protected:

include/llvm/Support/Host.h

@@ -15,7 +15,6 @@
 #define LLVM_SUPPORT_HOST_H
 
 #include "llvm/ADT/StringMap.h"
-#include "llvm/Support/MemoryBuffer.h"
 
 #if defined(__linux__) || defined(__GNU__) || defined(__HAIKU__)
 #include <endian.h>

lib/DebugInfo/PDB/PDB.cpp

@@ -16,6 +16,7 @@
 #endif
 #include "llvm/DebugInfo/PDB/Native/NativeSession.h"
 #include "llvm/Support/Error.h"
+#include "llvm/Support/MemoryBuffer.h"
 
 using namespace llvm;
 using namespace llvm::pdb;

lib/Support/CodeGenCoverage.cpp

@@ -14,6 +14,7 @@
 
 #include "llvm/Support/Endian.h"
 #include "llvm/Support/FileSystem.h"
+#include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/Mutex.h"
 #include "llvm/Support/ScopedPrinter.h"
 #include "llvm/Support/ToolOutputFile.h"

tools/llvm-mt/llvm-mt.cpp

@@ -18,6 +18,7 @@
 #include "llvm/Support/Error.h"
 #include "llvm/Support/FileOutputBuffer.h"
 #include "llvm/Support/ManagedStatic.h"
+#include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/PrettyStackTrace.h"
 #include "llvm/Support/Process.h"

tools/llvm-rc/ResourceFileWriter.cpp

@@ -17,6 +17,7 @@
 #include "llvm/Support/ConvertUTF.h"
 #include "llvm/Support/Endian.h"
 #include "llvm/Support/EndianStream.h"
+#include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Process.h"
 

tools/llvm-rc/ResourceFileWriter.h

@@ -20,6 +20,9 @@
 #include "llvm/Support/Endian.h"
 
 namespace llvm {
+
+class MemoryBuffer;
+
 namespace rc {
 
 struct SearchParams {

tools/llvm-rc/llvm-rc.cpp

@@ -22,6 +22,7 @@
 #include "llvm/Support/Error.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/ManagedStatic.h"
+#include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/PrettyStackTrace.h"
 #include "llvm/Support/Process.h"
 #include "llvm/Support/Signals.h"