//===-- Local.h - Functions to perform local transformations ----*- C++ -*-===//
-//
+//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
+//
//===----------------------------------------------------------------------===//
//
// This family of functions perform various local transformations to the
namespace llvm {
class Pass;
+class PHINode;
+class AllocaInst;
+class ConstantExpr;
//===----------------------------------------------------------------------===//
// Local constant propagation...
///
bool ConstantFoldTerminator(BasicBlock *BB);
+/// ConstantFoldInstruction - Attempt to constant fold the specified
+/// instruction. If successful, the constant result is returned, if not, null
+/// is returned. Note that this function can only fail when attempting to fold
+/// instructions like loads and stores, which have no constant expression form.
+///
+Constant *ConstantFoldInstruction(Instruction *I);
+
+
+/// canConstantFoldCallTo - Return true if its even possible to fold a call to
+/// the specified function.
+bool canConstantFoldCallTo(Function *F);
+
+/// ConstantFoldCall - Attempt to constant fold a call to the specified function
+/// with the specified arguments, returning null if unsuccessful.
+Constant *ConstantFoldCall(Function *F, const std::vector<Constant*> &Operands);
+
+/// ConstantFoldLoadThroughGEPConstantExpr - Given a constant and a
+/// getelementptr constantexpr, return the constant value being addressed by the
+/// constant expression, or null if something is funny and we can't decide.
+Constant *ConstantFoldLoadThroughGEPConstantExpr(Constant *C, ConstantExpr *CE);
//===----------------------------------------------------------------------===//
// Local dead code elimination...
///
bool dceInstruction(BasicBlock::iterator &BBI);
-
//===----------------------------------------------------------------------===//
// Control Flow Graph Restructuring...
//
///
bool SimplifyCFG(BasicBlock *BB);
+/// DemoteRegToStack - This function takes a virtual register computed by an
+/// Instruction and replaces it with a slot in the stack frame, allocated via
+/// alloca. This allows the CFG to be changed around without fear of
+/// invalidating the SSA information for the value. It returns the pointer to
+/// the alloca inserted to create a stack slot for X.
+///
+AllocaInst *DemoteRegToStack(Instruction &X, bool VolatileLoads = false);
+
} // End llvm namespace
#endif