Extracted pass ObjCARCExpand from ObjCARC.cpp => ObjCARCExpand.cpp.

I also added the local header ObjCARC.h for common functions used by the
various passes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173651 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 242 insertions, 0 deletions

diff --git a/lib/Transforms/ObjCARC/ObjCARC.h b/lib/Transforms/ObjCARC/ObjCARC.h
new file mode 100644
index 0000000000..ac04cad764
--- /dev/null
+++ b/lib/Transforms/ObjCARC/ObjCARC.h
@@ -0,0 +1,242 @@
+//===- ObjCARC.h - ObjC ARC Optimization --------------*- mode: c++ -*-----===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+/// \file
+/// This file defines common definitions/declarations used by the ObjC ARC
+/// Optimizer. ARC stands for Automatic Reference Counting and is a system for
+/// managing reference counts for objects in Objective C.
+///
+/// WARNING: This file knows about certain library functions. It recognizes them
+/// by name, and hardwires knowledge of their semantics.
+///
+/// WARNING: This file knows about how certain Objective-C library functions are
+/// used. Naive LLVM IR transformations which would otherwise be
+/// behavior-preserving may break these assumptions.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_SCALAR_OBJCARC_H
+#define LLVM_TRANSFORMS_SCALAR_OBJCARC_H
+
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/Passes.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/InstIterator.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Transforms/ObjCARC.h"
+
+namespace llvm {
+namespace objcarc {
+
+/// \brief A handy option to enable/disable all ARC Optimizations.
+extern bool EnableARCOpts;
+
+/// \brief Test if the given module looks interesting to run ARC optimization
+/// on.
+static inline bool ModuleHasARC(const Module &M) {
+  return
+    M.getNamedValue("objc_retain") ||
+    M.getNamedValue("objc_release") ||
+    M.getNamedValue("objc_autorelease") ||
+    M.getNamedValue("objc_retainAutoreleasedReturnValue") ||
+    M.getNamedValue("objc_retainBlock") ||
+    M.getNamedValue("objc_autoreleaseReturnValue") ||
+    M.getNamedValue("objc_autoreleasePoolPush") ||
+    M.getNamedValue("objc_loadWeakRetained") ||
+    M.getNamedValue("objc_loadWeak") ||
+    M.getNamedValue("objc_destroyWeak") ||
+    M.getNamedValue("objc_storeWeak") ||
+    M.getNamedValue("objc_initWeak") ||
+    M.getNamedValue("objc_moveWeak") ||
+    M.getNamedValue("objc_copyWeak") ||
+    M.getNamedValue("objc_retainedObject") ||
+    M.getNamedValue("objc_unretainedObject") ||
+    M.getNamedValue("objc_unretainedPointer");
+}
+
+/// \enum InstructionClass
+/// \brief A simple classification for instructions.
+enum InstructionClass {
+  IC_Retain,              ///< objc_retain
+  IC_RetainRV,            ///< objc_retainAutoreleasedReturnValue
+  IC_RetainBlock,         ///< objc_retainBlock
+  IC_Release,             ///< objc_release
+  IC_Autorelease,         ///< objc_autorelease
+  IC_AutoreleaseRV,       ///< objc_autoreleaseReturnValue
+  IC_AutoreleasepoolPush, ///< objc_autoreleasePoolPush
+  IC_AutoreleasepoolPop,  ///< objc_autoreleasePoolPop
+  IC_NoopCast,            ///< objc_retainedObject, etc.
+  IC_FusedRetainAutorelease, ///< objc_retainAutorelease
+  IC_FusedRetainAutoreleaseRV, ///< objc_retainAutoreleaseReturnValue
+  IC_LoadWeakRetained,    ///< objc_loadWeakRetained (primitive)
+  IC_StoreWeak,           ///< objc_storeWeak (primitive)
+  IC_InitWeak,            ///< objc_initWeak (derived)
+  IC_LoadWeak,            ///< objc_loadWeak (derived)
+  IC_MoveWeak,            ///< objc_moveWeak (derived)
+  IC_CopyWeak,            ///< objc_copyWeak (derived)
+  IC_DestroyWeak,         ///< objc_destroyWeak (derived)
+  IC_StoreStrong,         ///< objc_storeStrong (derived)
+  IC_CallOrUser,          ///< could call objc_release and/or "use" pointers
+  IC_Call,                ///< could call objc_release
+  IC_User,                ///< could "use" a pointer
+  IC_None                 ///< anything else
+};
+
+static raw_ostream &operator<<(raw_ostream &OS, const InstructionClass Class)
+  LLVM_ATTRIBUTE_USED;
+
+static raw_ostream &operator<<(raw_ostream &OS, const InstructionClass Class) {
+  switch (Class) {
+  case IC_Retain:
+    return OS << "IC_Retain";
+  case IC_RetainRV:
+    return OS << "IC_RetainRV";
+  case IC_RetainBlock:
+    return OS << "IC_RetainBlock";
+  case IC_Release:
+    return OS << "IC_Release";
+  case IC_Autorelease:
+    return OS << "IC_Autorelease";
+  case IC_AutoreleaseRV:
+    return OS << "IC_AutoreleaseRV";
+  case IC_AutoreleasepoolPush:
+    return OS << "IC_AutoreleasepoolPush";
+  case IC_AutoreleasepoolPop:
+    return OS << "IC_AutoreleasepoolPop";
+  case IC_NoopCast:
+    return OS << "IC_NoopCast";
+  case IC_FusedRetainAutorelease:
+    return OS << "IC_FusedRetainAutorelease";
+  case IC_FusedRetainAutoreleaseRV:
+    return OS << "IC_FusedRetainAutoreleaseRV";
+  case IC_LoadWeakRetained:
+    return OS << "IC_LoadWeakRetained";
+  case IC_StoreWeak:
+    return OS << "IC_StoreWeak";
+  case IC_InitWeak:
+    return OS << "IC_InitWeak";
+  case IC_LoadWeak:
+    return OS << "IC_LoadWeak";
+  case IC_MoveWeak:
+    return OS << "IC_MoveWeak";
+  case IC_CopyWeak:
+    return OS << "IC_CopyWeak";
+  case IC_DestroyWeak:
+    return OS << "IC_DestroyWeak";
+  case IC_StoreStrong:
+    return OS << "IC_StoreStrong";
+  case IC_CallOrUser:
+    return OS << "IC_CallOrUser";
+  case IC_Call:
+    return OS << "IC_Call";
+  case IC_User:
+    return OS << "IC_User";
+  case IC_None:
+    return OS << "IC_None";
+  }
+  llvm_unreachable("Unknown instruction class!");
+}
+
+
+/// \brief Determine if F is one of the special known Functions.  If it isn't,
+/// return IC_CallOrUser.
+static inline InstructionClass GetFunctionClass(const Function *F) {
+  Function::const_arg_iterator AI = F->arg_begin(), AE = F->arg_end();
+
+  // No arguments.
+  if (AI == AE)
+    return StringSwitch<InstructionClass>(F->getName())
+      .Case("objc_autoreleasePoolPush",  IC_AutoreleasepoolPush)
+      .Default(IC_CallOrUser);
+
+  // One argument.
+  const Argument *A0 = AI++;
+  if (AI == AE)
+    // Argument is a pointer.
+    if (PointerType *PTy = dyn_cast<PointerType>(A0->getType())) {
+      Type *ETy = PTy->getElementType();
+      // Argument is i8*.
+      if (ETy->isIntegerTy(8))
+        return StringSwitch<InstructionClass>(F->getName())
+          .Case("objc_retain",                IC_Retain)
+          .Case("objc_retainAutoreleasedReturnValue", IC_RetainRV)
+          .Case("objc_retainBlock",           IC_RetainBlock)
+          .Case("objc_release",               IC_Release)
+          .Case("objc_autorelease",           IC_Autorelease)
+          .Case("objc_autoreleaseReturnValue", IC_AutoreleaseRV)
+          .Case("objc_autoreleasePoolPop",    IC_AutoreleasepoolPop)
+          .Case("objc_retainedObject",        IC_NoopCast)
+          .Case("objc_unretainedObject",      IC_NoopCast)
+          .Case("objc_unretainedPointer",     IC_NoopCast)
+          .Case("objc_retain_autorelease",    IC_FusedRetainAutorelease)
+          .Case("objc_retainAutorelease",     IC_FusedRetainAutorelease)
+          .Case("objc_retainAutoreleaseReturnValue",IC_FusedRetainAutoreleaseRV)
+          .Default(IC_CallOrUser);
+
+      // Argument is i8**
+      if (PointerType *Pte = dyn_cast<PointerType>(ETy))
+        if (Pte->getElementType()->isIntegerTy(8))
+          return StringSwitch<InstructionClass>(F->getName())
+            .Case("objc_loadWeakRetained",      IC_LoadWeakRetained)
+            .Case("objc_loadWeak",              IC_LoadWeak)
+            .Case("objc_destroyWeak",           IC_DestroyWeak)
+            .Default(IC_CallOrUser);
+    }
+
+  // Two arguments, first is i8**.
+  const Argument *A1 = AI++;
+  if (AI == AE)
+    if (PointerType *PTy = dyn_cast<PointerType>(A0->getType()))
+      if (PointerType *Pte = dyn_cast<PointerType>(PTy->getElementType()))
+        if (Pte->getElementType()->isIntegerTy(8))
+          if (PointerType *PTy1 = dyn_cast<PointerType>(A1->getType())) {
+            Type *ETy1 = PTy1->getElementType();
+            // Second argument is i8*
+            if (ETy1->isIntegerTy(8))
+              return StringSwitch<InstructionClass>(F->getName())
+                     .Case("objc_storeWeak",             IC_StoreWeak)
+                     .Case("objc_initWeak",              IC_InitWeak)
+                     .Case("objc_storeStrong",           IC_StoreStrong)
+                     .Default(IC_CallOrUser);
+            // Second argument is i8**.
+            if (PointerType *Pte1 = dyn_cast<PointerType>(ETy1))
+              if (Pte1->getElementType()->isIntegerTy(8))
+                return StringSwitch<InstructionClass>(F->getName())
+                       .Case("objc_moveWeak",              IC_MoveWeak)
+                       .Case("objc_copyWeak",              IC_CopyWeak)
+                       .Default(IC_CallOrUser);
+          }
+
+  // Anything else.
+  return IC_CallOrUser;
+}
+
+/// \brief Determine which objc runtime call instruction class V belongs to.
+///
+/// This is similar to GetInstructionClass except that it only detects objc
+/// runtime calls. This allows it to be faster.
+///
+static inline InstructionClass GetBasicInstructionClass(const Value *V) {
+  if (const CallInst *CI = dyn_cast<CallInst>(V)) {
+    if (const Function *F = CI->getCalledFunction())
+      return GetFunctionClass(F);
+    // Otherwise, be conservative.
+    return IC_CallOrUser;
+  }
+
+  // Otherwise, be conservative.
+  return isa<InvokeInst>(V) ? IC_CallOrUser : IC_User;
+}
+
+} // end namespace objcarc
+} // end namespace llvm
+
+#endif // LLVM_TRANSFORMS_SCALAR_OBJCARC_H