[llvm-commits] CVS: llvm/include/llvm/CodeGen/CallingConvLower.h

[Chris Lattner]

Changes in directory llvm/include/llvm/CodeGen:

CallingConvLower.h added (r1.1)
---
Log message:

move CC Lowering stuff to its own public interface


---
Diffs of the changes:  (+149 -0)

 CallingConvLower.h |  149 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 149 insertions(+)


Index: llvm/include/llvm/CodeGen/CallingConvLower.h
diff -c /dev/null llvm/include/llvm/CodeGen/CallingConvLower.h:1.1
*** /dev/null	Mon Feb 26 22:43:12 2007
--- llvm/include/llvm/CodeGen/CallingConvLower.h	Mon Feb 26 22:43:02 2007
***************
*** 0 ****
--- 1,149 ----
+ //===-- llvm/CallingConvLower.h - Calling Conventions -----------*- C++ -*-===//
+ //
+ //                     The LLVM Compiler Infrastructure
+ //
+ // This file was developed by Chris Lattner and is distributed under
+ // the University of Illinois Open Source License. See LICENSE.TXT for details.
+ //
+ //===----------------------------------------------------------------------===//
+ //
+ // This file declares the CCState and CCValAssign classes, used for lowering
+ // and implementing calling conventions.
+ //
+ //===----------------------------------------------------------------------===//
+ 
+ #ifndef LLVM_CODEGEN_CALLINGCONVLOWER_H
+ #define LLVM_CODEGEN_CALLINGCONVLOWER_H
+ 
+ #include "llvm/ADT/SmallVector.h"
+ #include "llvm/CodeGen/ValueTypes.h"
+ 
+ namespace llvm {
+   class MRegisterInfo;
+   
+ /// CCState - This class holds information needed while lowering arguments and
+ /// return values.  It captures which registers are already assigned and which
+ /// stack slots are used.  It provides accessors to allocate these values.
+ class CCState {
+   unsigned StackOffset;
+   const MRegisterInfo &MRI;
+   SmallVector<uint32_t, 16> UsedRegs;
+ public:
+   CCState(const MRegisterInfo &mri);
+   
+   unsigned getNextStackOffset() const { return StackOffset; }
+ 
+   /// isAllocated - Return true if the specified register (or an alias) is
+   /// allocated.
+   bool isAllocated(unsigned Reg) const {
+     return UsedRegs[Reg/32] & (1 << (Reg&31));
+   }
+ 
+   /// getFirstUnallocated - Return the first unallocated register in the set, or
+   /// NumRegs if they are all allocated.
+   unsigned getFirstUnallocated(const unsigned *Regs, unsigned NumRegs) const {
+     for (unsigned i = 0; i != NumRegs; ++i)
+       if (!isAllocated(Regs[i]))
+         return i;
+     return NumRegs;
+   }
+   
+   /// AllocateReg - Attempt to allocate one of the specified registers.  If none
+   /// are available, return zero.  Otherwise, return the first one available,
+   /// marking it and any aliases as allocated.
+   unsigned AllocateReg(const unsigned *Regs, unsigned NumRegs) {
+     unsigned FirstUnalloc = getFirstUnallocated(Regs, NumRegs);
+     if (FirstUnalloc == NumRegs)
+       return 0;    // Didn't find the reg.
+      
+     // Mark the register and any aliases as allocated.
+     unsigned Reg = Regs[FirstUnalloc];
+     MarkAllocated(Reg);
+     return Reg;
+   }
+   
+   /// AllocateStack - Allocate a chunk of stack space with the specified size
+   /// and alignment.
+   unsigned AllocateStack(unsigned Size, unsigned Align) {
+     assert(Align && ((Align-1) & Align) == 0); // Align is power of 2.
+     StackOffset = ((StackOffset + Align-1) & ~(Align-1));
+     unsigned Result = StackOffset;
+     StackOffset += Size;
+     return Result;
+   }
+ private:
+   /// MarkAllocated - Mark a register and all of its aliases as allocated.
+   void MarkAllocated(unsigned Reg);
+ };
+ 
+ /// CCValAssign - Represent assignment of one arg/retval to a location.
+ class CCValAssign {
+ public:
+   enum LocInfo {
+     Full,   // The value fills the full location.
+     SExt,   // The value is sign extended in the location.
+     ZExt,   // The value is zero extended in the location.
+     AExt    // The value is extended with undefined upper bits.
+     // TODO: a subset of the value is in the location.
+   };
+ private:
+   /// ValNo - This is the value number begin assigned (e.g. an argument number).
+   unsigned ValNo;
+   
+   /// Loc is either a stack offset or a register number.
+   unsigned Loc;
+   
+   /// isMem - True if this is a memory loc, false if it is a register loc.
+   bool isMem : 1;
+   
+   /// Information about how the value is assigned.
+   LocInfo HTP : 7;
+   
+   /// ValVT - The type of the value being assigned.
+   MVT::ValueType ValVT : 8;
+ 
+   /// LocVT - The type of the location being assigned to.
+   MVT::ValueType LocVT : 8;
+ public:
+     
+   static CCValAssign getReg(unsigned ValNo, MVT::ValueType ValVT,
+                             unsigned RegNo, MVT::ValueType LocVT,
+                             LocInfo HTP) {
+     CCValAssign Ret;
+     Ret.ValNo = ValNo;
+     Ret.Loc = RegNo;
+     Ret.isMem = false;
+     Ret.HTP = HTP;
+     Ret.ValVT = ValVT;
+     Ret.LocVT = LocVT;
+     return Ret;
+   }
+   static CCValAssign getMem(unsigned ValNo, MVT::ValueType ValVT,
+                             unsigned Offset, MVT::ValueType LocVT,
+                             LocInfo HTP) {
+     CCValAssign Ret;
+     Ret.ValNo = ValNo;
+     Ret.Loc = Offset;
+     Ret.isMem = true;
+     Ret.HTP = HTP;
+     Ret.ValVT = ValVT;
+     Ret.LocVT = LocVT;
+     return Ret;
+   }
+   
+   unsigned getValNo() const { return ValNo; }
+   MVT::ValueType getValVT() const { return ValVT; }
+ 
+   bool isRegLoc() const { return !isMem; }
+   bool isMemLoc() const { return isMem; }
+   
+   unsigned getLocReg() const { assert(isRegLoc()); return Loc; }
+   unsigned getLocMemOffset() const { assert(isMemLoc()); return Loc; }
+   MVT::ValueType getLocVT() const { return LocVT; }
+   
+   LocInfo getLocInfo() const { return HTP; }
+ };
+ 
+ } // end namespace llvm
+ 
+ #endif