Jim Stichnoth | 5bc2b1d | 2014-05-22 13:38:48 -0700 | [diff] [blame] | 1 | //===- subzero/src/IceTargetLowering.h - Lowering interface -----*- C++ -*-===// |
| 2 | // |
| 3 | // The Subzero Code Generator |
| 4 | // |
| 5 | // This file is distributed under the University of Illinois Open Source |
| 6 | // License. See LICENSE.TXT for details. |
| 7 | // |
| 8 | //===----------------------------------------------------------------------===// |
| 9 | // |
| 10 | // This file declares the TargetLowering and LoweringContext |
| 11 | // classes. TargetLowering is an abstract class used to drive the |
| 12 | // translation/lowering process. LoweringContext maintains a |
| 13 | // context for lowering each instruction, offering conveniences such |
| 14 | // as iterating over non-deleted instructions. |
| 15 | // |
| 16 | //===----------------------------------------------------------------------===// |
| 17 | |
| 18 | #ifndef SUBZERO_SRC_ICETARGETLOWERING_H |
| 19 | #define SUBZERO_SRC_ICETARGETLOWERING_H |
| 20 | |
| 21 | #include "IceDefs.h" |
| 22 | #include "IceTypes.h" |
| 23 | |
| 24 | #include "IceInst.h" // for the names of the Inst subtypes |
| 25 | |
| 26 | namespace Ice { |
| 27 | |
| 28 | // LoweringContext makes it easy to iterate through non-deleted |
| 29 | // instructions in a node, and insert new (lowered) instructions at |
| 30 | // the current point. Along with the instruction list container and |
| 31 | // associated iterators, it holds the current node, which is needed |
| 32 | // when inserting new instructions in order to track whether variables |
| 33 | // are used as single-block or multi-block. |
| 34 | class LoweringContext { |
| 35 | public: |
| 36 | LoweringContext() : Node(NULL) {} |
| 37 | ~LoweringContext() {} |
| 38 | void init(CfgNode *Node); |
| 39 | Inst *getNextInst() const { |
| 40 | if (Next == End) |
| 41 | return NULL; |
| 42 | return *Next; |
| 43 | } |
| 44 | CfgNode *getNode() const { return Node; } |
| 45 | bool atEnd() const { return Cur == End; } |
| 46 | InstList::iterator getCur() const { return Cur; } |
| 47 | InstList::iterator getEnd() const { return End; } |
| 48 | void insert(Inst *Inst); |
| 49 | void advanceCur() { Cur = Next; } |
| 50 | void advanceNext() { advance(Next); } |
| 51 | void setInsertPoint(const InstList::iterator &Position) { Next = Position; } |
| 52 | |
| 53 | private: |
| 54 | // Node is the argument to Inst::updateVars(). |
| 55 | CfgNode *Node; |
| 56 | // Cur points to the current instruction being considered. It is |
| 57 | // guaranteed to point to a non-deleted instruction, or to be End. |
| 58 | InstList::iterator Cur; |
| 59 | // Next doubles as a pointer to the next valid instruction (if any), |
| 60 | // and the new-instruction insertion point. It is also updated for |
| 61 | // the caller in case the lowering consumes more than one high-level |
| 62 | // instruction. It is guaranteed to point to a non-deleted |
| 63 | // instruction after Cur, or to be End. TODO: Consider separating |
| 64 | // the notion of "next valid instruction" and "new instruction |
| 65 | // insertion point", to avoid confusion when previously-deleted |
| 66 | // instructions come between the two points. |
| 67 | InstList::iterator Next; |
| 68 | // End is a copy of Insts.end(), used if Next needs to be advanced. |
| 69 | InstList::iterator End; |
| 70 | |
| 71 | void skipDeleted(InstList::iterator &I); |
| 72 | void advance(InstList::iterator &I); |
| 73 | LoweringContext(const LoweringContext &) LLVM_DELETED_FUNCTION; |
| 74 | LoweringContext &operator=(const LoweringContext &) LLVM_DELETED_FUNCTION; |
| 75 | }; |
| 76 | |
| 77 | class TargetLowering { |
| 78 | public: |
| 79 | static TargetLowering *createLowering(TargetArch Target, Cfg *Func); |
| 80 | void translate() { |
| 81 | switch (Ctx->getOptLevel()) { |
| 82 | case Opt_m1: |
| 83 | translateOm1(); |
| 84 | break; |
| 85 | case Opt_0: |
| 86 | translateO0(); |
| 87 | break; |
| 88 | case Opt_1: |
| 89 | translateO1(); |
| 90 | break; |
| 91 | case Opt_2: |
| 92 | translateO2(); |
| 93 | break; |
| 94 | default: |
| 95 | Func->setError("Target doesn't specify lowering steps."); |
| 96 | break; |
| 97 | } |
| 98 | } |
| 99 | virtual void translateOm1() { |
| 100 | Func->setError("Target doesn't specify Om1 lowering steps."); |
| 101 | } |
| 102 | virtual void translateO0() { |
| 103 | Func->setError("Target doesn't specify O0 lowering steps."); |
| 104 | } |
| 105 | virtual void translateO1() { |
| 106 | Func->setError("Target doesn't specify O1 lowering steps."); |
| 107 | } |
| 108 | virtual void translateO2() { |
| 109 | Func->setError("Target doesn't specify O2 lowering steps."); |
| 110 | } |
| 111 | |
Jim Stichnoth | d97c7df | 2014-06-04 11:57:08 -0700 | [diff] [blame] | 112 | // Tries to do address mode optimization on a single instruction. |
| 113 | void doAddressOpt(); |
Jim Stichnoth | 5bc2b1d | 2014-05-22 13:38:48 -0700 | [diff] [blame] | 114 | // Lowers a single instruction. |
| 115 | void lower(); |
| 116 | |
| 117 | // Returns a variable pre-colored to the specified physical |
| 118 | // register. This is generally used to get very direct access to |
| 119 | // the register such as in the prolog or epilog or for marking |
| 120 | // scratch registers as killed by a call. |
| 121 | virtual Variable *getPhysicalRegister(SizeT RegNum) = 0; |
| 122 | // Returns a printable name for the register. |
| 123 | virtual IceString getRegName(SizeT RegNum, Type Ty) const = 0; |
| 124 | |
| 125 | virtual bool hasFramePointer() const { return false; } |
| 126 | virtual SizeT getFrameOrStackReg() const = 0; |
| 127 | virtual size_t typeWidthInBytesOnStack(Type Ty) = 0; |
| 128 | bool hasComputedFrame() const { return HasComputedFrame; } |
| 129 | int32_t getStackAdjustment() const { return StackAdjustment; } |
| 130 | void updateStackAdjustment(int32_t Offset) { StackAdjustment += Offset; } |
| 131 | void resetStackAdjustment() { StackAdjustment = 0; } |
| 132 | LoweringContext &getContext() { return Context; } |
| 133 | |
| 134 | enum RegSet { |
| 135 | RegSet_None = 0, |
| 136 | RegSet_CallerSave = 1 << 0, |
| 137 | RegSet_CalleeSave = 1 << 1, |
| 138 | RegSet_StackPointer = 1 << 2, |
| 139 | RegSet_FramePointer = 1 << 3, |
| 140 | RegSet_All = ~RegSet_None |
| 141 | }; |
| 142 | typedef uint32_t RegSetMask; |
| 143 | |
| 144 | virtual llvm::SmallBitVector getRegisterSet(RegSetMask Include, |
| 145 | RegSetMask Exclude) const = 0; |
| 146 | virtual const llvm::SmallBitVector &getRegisterSetForType(Type Ty) const = 0; |
| 147 | void regAlloc(); |
| 148 | |
| 149 | virtual void emitVariable(const Variable *Var, const Cfg *Func) const = 0; |
| 150 | |
Matt Wala | 45a0623 | 2014-07-09 16:33:22 -0700 | [diff] [blame] | 151 | // Performs target-specific argument lowering. |
| 152 | virtual void lowerArguments() = 0; |
| 153 | |
Jim Stichnoth | 5bc2b1d | 2014-05-22 13:38:48 -0700 | [diff] [blame] | 154 | virtual void addProlog(CfgNode *Node) = 0; |
| 155 | virtual void addEpilog(CfgNode *Node) = 0; |
| 156 | |
Jim Stichnoth | f61d5b2 | 2014-05-23 13:31:24 -0700 | [diff] [blame] | 157 | virtual void emitConstants() const = 0; |
| 158 | |
Jim Stichnoth | 5bc2b1d | 2014-05-22 13:38:48 -0700 | [diff] [blame] | 159 | virtual ~TargetLowering() {} |
| 160 | |
| 161 | protected: |
| 162 | TargetLowering(Cfg *Func) |
| 163 | : Func(Func), Ctx(Func->getContext()), HasComputedFrame(false), |
| 164 | StackAdjustment(0) {} |
| 165 | virtual void lowerAlloca(const InstAlloca *Inst) = 0; |
| 166 | virtual void lowerArithmetic(const InstArithmetic *Inst) = 0; |
| 167 | virtual void lowerAssign(const InstAssign *Inst) = 0; |
| 168 | virtual void lowerBr(const InstBr *Inst) = 0; |
| 169 | virtual void lowerCall(const InstCall *Inst) = 0; |
| 170 | virtual void lowerCast(const InstCast *Inst) = 0; |
| 171 | virtual void lowerFcmp(const InstFcmp *Inst) = 0; |
Matt Wala | 4988923 | 2014-07-18 12:45:09 -0700 | [diff] [blame] | 172 | virtual void lowerExtractElement(const InstExtractElement *Inst) = 0; |
Jim Stichnoth | 5bc2b1d | 2014-05-22 13:38:48 -0700 | [diff] [blame] | 173 | virtual void lowerIcmp(const InstIcmp *Inst) = 0; |
Matt Wala | 4988923 | 2014-07-18 12:45:09 -0700 | [diff] [blame] | 174 | virtual void lowerInsertElement(const InstInsertElement *Inst) = 0; |
Jan Voung | 3bd9f1a | 2014-06-18 10:50:57 -0700 | [diff] [blame] | 175 | virtual void lowerIntrinsicCall(const InstIntrinsicCall *Inst) = 0; |
Jim Stichnoth | 5bc2b1d | 2014-05-22 13:38:48 -0700 | [diff] [blame] | 176 | virtual void lowerLoad(const InstLoad *Inst) = 0; |
| 177 | virtual void lowerPhi(const InstPhi *Inst) = 0; |
| 178 | virtual void lowerRet(const InstRet *Inst) = 0; |
| 179 | virtual void lowerSelect(const InstSelect *Inst) = 0; |
| 180 | virtual void lowerStore(const InstStore *Inst) = 0; |
| 181 | virtual void lowerSwitch(const InstSwitch *Inst) = 0; |
| 182 | virtual void lowerUnreachable(const InstUnreachable *Inst) = 0; |
| 183 | |
Jim Stichnoth | d97c7df | 2014-06-04 11:57:08 -0700 | [diff] [blame] | 184 | virtual void doAddressOptLoad() {} |
| 185 | virtual void doAddressOptStore() {} |
Jim Stichnoth | 5bc2b1d | 2014-05-22 13:38:48 -0700 | [diff] [blame] | 186 | // This gives the target an opportunity to post-process the lowered |
| 187 | // expansion before returning. The primary intention is to do some |
| 188 | // Register Manager activity as necessary, specifically to eagerly |
| 189 | // allocate registers based on affinity and other factors. The |
| 190 | // simplest lowering does nothing here and leaves it all to a |
| 191 | // subsequent global register allocation pass. |
| 192 | virtual void postLower() {} |
| 193 | |
| 194 | Cfg *Func; |
| 195 | GlobalContext *Ctx; |
| 196 | bool HasComputedFrame; |
| 197 | // StackAdjustment keeps track of the current stack offset from its |
| 198 | // natural location, as arguments are pushed for a function call. |
| 199 | int32_t StackAdjustment; |
| 200 | LoweringContext Context; |
| 201 | |
| 202 | private: |
| 203 | TargetLowering(const TargetLowering &) LLVM_DELETED_FUNCTION; |
| 204 | TargetLowering &operator=(const TargetLowering &) LLVM_DELETED_FUNCTION; |
| 205 | }; |
| 206 | |
Jim Stichnoth | de4ca71 | 2014-06-29 08:13:48 -0700 | [diff] [blame] | 207 | // TargetGlobalInitLowering is used for "lowering" global |
| 208 | // initializers. It is separated out from TargetLowering because it |
| 209 | // does not require a Cfg. |
| 210 | class TargetGlobalInitLowering { |
| 211 | public: |
| 212 | static TargetGlobalInitLowering *createLowering(TargetArch Target, |
| 213 | GlobalContext *Ctx); |
Jan Voung | 839c4ce | 2014-07-28 15:19:43 -0700 | [diff] [blame^] | 214 | virtual ~TargetGlobalInitLowering(); |
| 215 | |
Jim Stichnoth | de4ca71 | 2014-06-29 08:13:48 -0700 | [diff] [blame] | 216 | // TODO: Allow relocations to be represented as part of the Data. |
| 217 | virtual void lower(const IceString &Name, SizeT Align, bool IsInternal, |
| 218 | bool IsConst, bool IsZeroInitializer, SizeT Size, |
| 219 | const char *Data, bool DisableTranslation) = 0; |
| 220 | |
| 221 | protected: |
| 222 | TargetGlobalInitLowering(GlobalContext *Ctx) : Ctx(Ctx) {} |
| 223 | GlobalContext *Ctx; |
| 224 | |
| 225 | private: |
| 226 | TargetGlobalInitLowering(const TargetGlobalInitLowering &) |
| 227 | LLVM_DELETED_FUNCTION; |
| 228 | TargetGlobalInitLowering & |
| 229 | operator=(const TargetGlobalInitLowering &) LLVM_DELETED_FUNCTION; |
| 230 | }; |
| 231 | |
Jim Stichnoth | 5bc2b1d | 2014-05-22 13:38:48 -0700 | [diff] [blame] | 232 | } // end of namespace Ice |
| 233 | |
| 234 | #endif // SUBZERO_SRC_ICETARGETLOWERING_H |