Unify alloca, outgoing arg, and prolog construction

src/IceTargetLowering.h

 //===- subzero/src/IceTargetLowering.h - Lowering interface -----*- C++ -*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 203 matching lines @@
   virtual uint32_t maxOutArgsSizeBytes() const { return 0; }
 
   /// Return whether a 64-bit Variable should be split into a Variable64On32.
   virtual bool shouldSplitToVariable64On32(Type Ty) const = 0;
 
   bool hasComputedFrame() const { return HasComputedFrame; }
   /// Returns true if this function calls a function that has the "returns
   /// twice" attribute.
   bool callsReturnsTwice() const { return CallsReturnsTwice; }
   void setCallsReturnsTwice(bool RetTwice) { CallsReturnsTwice = RetTwice; }
-  int32_t getStackAdjustment() const { return StackAdjustment; }
-  void updateStackAdjustment(int32_t Offset) { StackAdjustment += Offset; }
-  void resetStackAdjustment() { StackAdjustment = 0; }
   SizeT makeNextLabelNumber() { return NextLabelNumber++; }
   SizeT makeNextJumpTableNumber() { return NextJumpTableNumber++; }
   LoweringContext &getContext() { return Context; }
 
   enum RegSet {
     RegSet_None = 0,
     RegSet_CallerSave = 1 << 0,
     RegSet_CalleeSave = 1 << 1,
     RegSet_StackPointer = 1 << 2,
     RegSet_FramePointer = 1 << 3,
     RegSet_All = ~RegSet_None
   };
   using RegSetMask = uint32_t;
 
   virtual llvm::SmallBitVector getRegisterSet(RegSetMask Include,
                                               RegSetMask Exclude) const = 0;
   virtual const llvm::SmallBitVector &
   getRegistersForVariable(const Variable *Var) const = 0;
   virtual const llvm::SmallBitVector &getAliasesForRegister(SizeT) const = 0;
 
   void regAlloc(RegAllocKind Kind);
 
   virtual void
   makeRandomRegisterPermutation(llvm::SmallVectorImpl<int32_t> &Permutation,
                                 const llvm::SmallBitVector &ExcludeRegisters,
                                 uint64_t Salt) const = 0;
 
-  /// Save/restore any mutable state for the situation where code emission needs
-  /// multiple passes, such as sandboxing or relaxation. Subclasses may provide
-  /// their own implementation, but should be sure to also call the parent
-  /// class's methods.
-  virtual void snapshotEmitState() {
-    SnapshotStackAdjustment = StackAdjustment;
-  }
-  virtual void rollbackEmitState() {
-    StackAdjustment = SnapshotStackAdjustment;
-  }
-
   /// Get the minimum number of clusters required for a jump table to be
   /// considered.
   virtual SizeT getMinJumpTableSize() const = 0;
   virtual void emitJumpTable(const Cfg *Func,
                              const InstJumpTable *JumpTable) const = 0;
 
   virtual void emitVariable(const Variable *Var) const = 0;
 
   void emitWithoutPrefix(const ConstantRelocatable *CR) const;
   void emit(const ConstantRelocatable *CR) const;
@@ skipping 111 matching lines @@
   }
   void _bundle_unlock() { Context.insert(InstBundleUnlock::create(Func)); }
   void _set_dest_redefined() { Context.getLastInserted()->setDestRedefined(); }
 
   bool shouldOptimizeMemIntrins();
 
   Cfg *Func;
   GlobalContext *Ctx;
   bool HasComputedFrame = false;
   bool CallsReturnsTwice = false;
-  /// StackAdjustment keeps track of the current stack offset from its natural
-  /// location, e.g. as arguments are pushed for a function call or as
-  /// fixed-size alloca instructions are executed in the entry block.
-  int32_t StackAdjustment = 0;
   SizeT NextLabelNumber = 0;
   SizeT NextJumpTableNumber = 0;
   LoweringContext Context;
 
   // Runtime helper function names
   const static constexpr char *H_bitcast_16xi1_i16 = "__Sz_bitcast_16xi1_i16";
   const static constexpr char *H_bitcast_8xi1_i8 = "__Sz_bitcast_8xi1_i8";
   const static constexpr char *H_bitcast_i16_16xi1 = "__Sz_bitcast_i16_16xi1";
   const static constexpr char *H_bitcast_i8_8xi1 = "__Sz_bitcast_i8_8xi1";
   const static constexpr char *H_call_ctpop_i32 = "__popcountsi2";
@@ skipping 21 matching lines @@
   const static constexpr char *H_srem_i64 = "__moddi3";
   const static constexpr char *H_udiv_i32 = "__udivsi3";
   const static constexpr char *H_udiv_i64 = "__udivdi3";
   const static constexpr char *H_uitofp_4xi32_4xf32 = "__Sz_uitofp_4xi32_4xf32";
   const static constexpr char *H_uitofp_i32_f32 = "__Sz_uitofp_i32_f32";
   const static constexpr char *H_uitofp_i32_f64 = "__Sz_uitofp_i32_f64";
   const static constexpr char *H_uitofp_i64_f32 = "__Sz_uitofp_i64_f32";
   const static constexpr char *H_uitofp_i64_f64 = "__Sz_uitofp_i64_f64";
   const static constexpr char *H_urem_i32 = "__umodsi3";
   const static constexpr char *H_urem_i64 = "__umoddi3";
-
-private:
-  int32_t SnapshotStackAdjustment = 0;
 };
 
 /// TargetDataLowering is used for "lowering" data including initializers for
 /// global variables, and the internal constant pools. It is separated out from
 /// TargetLowering because it does not require a Cfg.
 class TargetDataLowering {
   TargetDataLowering() = delete;
   TargetDataLowering(const TargetDataLowering &) = delete;
   TargetDataLowering &operator=(const TargetDataLowering &) = delete;
 
@@ skipping 35 matching lines @@
   virtual void lower() {}
 
 protected:
   explicit TargetHeaderLowering(GlobalContext *Ctx) : Ctx(Ctx) {}
   GlobalContext *Ctx;
 };
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICETARGETLOWERING_H