1 //===- Target.td - Target Independent TableGen interface ---*- tablegen -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the target-independent interfaces which should be
11 // implemented by each target which is using a TableGen based code generator.
13 //===----------------------------------------------------------------------===//
15 include "llvm/CodeGen/ValueTypes.td"
17 //===----------------------------------------------------------------------===//
18 // Register file description - These classes are used to fill in the target
19 // description classes.
21 class RegisterClass; // Forward def
23 // Register - You should define one instance of this class for each register
24 // in the target machine. String n will become the "name" of the register.
25 class Register<string n> {
26 string Namespace = "";
29 // SpillSize - If this value is set to a non-zero value, it is the size in
30 // bits of the spill slot required to hold this register. If this value is
31 // set to zero, the information is inferred from any register classes the
32 // register belongs to.
35 // SpillAlignment - This value is used to specify the alignment required for
36 // spilling the register. Like SpillSize, this should only be explicitly
37 // specified if the register is not in a register class.
38 int SpillAlignment = 0;
40 // Aliases - A list of registers that this register overlaps with. A read or
41 // modification of this register can potentially read or modifie the aliased
44 list<Register> Aliases = [];
47 // RegisterGroup - This can be used to define instances of Register which
48 // need to specify aliases.
49 // List "aliases" specifies which registers are aliased to this one. This
50 // allows the code generator to be careful not to put two values with
51 // overlapping live ranges into registers which alias.
52 class RegisterGroup<string n, list<Register> aliases> : Register<n> {
53 let Aliases = aliases;
56 // RegisterClass - Now that all of the registers are defined, and aliases
57 // between registers are defined, specify which registers belong to which
58 // register classes. This also defines the default allocation order of
59 // registers by register allocators.
61 class RegisterClass<string namespace, list<ValueType> regTypes, int alignment,
62 list<Register> regList> {
63 string Namespace = namespace;
65 // RegType - Specify the ValueType of the registers in this register class.
66 // Note that all registers in a register class must have the same ValueType.
68 list<ValueType> RegTypes = regTypes;
70 // Size - Specify the spill size in bits of the registers. A default value of
71 // zero lets tablgen pick an appropriate size.
74 // Alignment - Specify the alignment required of the registers when they are
75 // stored or loaded to memory.
77 int Alignment = alignment;
79 // MemberList - Specify which registers are in this class. If the
80 // allocation_order_* method are not specified, this also defines the order of
81 // allocation used by the register allocator.
83 list<Register> MemberList = regList;
85 // MethodProtos/MethodBodies - These members can be used to insert arbitrary
86 // code into a generated register class. The normal usage of this is to
87 // overload virtual methods.
88 code MethodProtos = [{}];
89 code MethodBodies = [{}];
93 //===----------------------------------------------------------------------===//
94 // Pull in the common support for scheduling
96 include "../TargetSchedule.td"
98 class Predicate; // Forward def
100 //===----------------------------------------------------------------------===//
101 // Instruction set description - These classes correspond to the C++ classes in
102 // the Target/TargetInstrInfo.h file.
105 string Name = ""; // The opcode string for this instruction
106 string Namespace = "";
108 dag OperandList; // An dag containing the MI operand list.
109 string AsmString = ""; // The .s format to print the instruction with.
111 // Pattern - Set to the DAG pattern for this instruction, if we know of one,
112 // otherwise, uninitialized.
115 // The follow state will eventually be inferred automatically from the
116 // instruction pattern.
118 list<Register> Uses = []; // Default to using no non-operand registers
119 list<Register> Defs = []; // Default to modifying no non-operand registers
121 // Predicates - List of predicates which will be turned into isel matching
123 list<Predicate> Predicates = [];
125 // These bits capture information about the high-level semantics of the
127 bit isReturn = 0; // Is this instruction a return instruction?
128 bit isBranch = 0; // Is this instruction a branch instruction?
129 bit isBarrier = 0; // Can control flow fall through this instruction?
130 bit isCall = 0; // Is this instruction a call instruction?
131 bit isLoad = 0; // Is this instruction a load instruction?
132 bit isStore = 0; // Is this instruction a store instruction?
133 bit isTwoAddress = 0; // Is this a two address instruction?
134 bit isConvertibleToThreeAddress = 0; // Can this 2-addr instruction promote?
135 bit isCommutable = 0; // Is this 3 operand instruction commutable?
136 bit isTerminator = 0; // Is this part of the terminator for a basic block?
137 bit hasDelaySlot = 0; // Does this instruction have an delay slot?
138 bit usesCustomDAGSchedInserter = 0; // Pseudo instr needing special help.
139 bit hasCtrlDep = 0; // Does this instruction r/w ctrl-flow chains?
140 bit noResults = 0; // Does this instruction produce no results?
142 InstrItinClass Itinerary = NoItinerary;// Execution steps used for scheduling.
145 /// Predicates - These are extra conditionals which are turned into instruction
146 /// selector matching code. Currently each predicate is just a string.
147 class Predicate<string cond> {
148 string CondString = cond;
151 class Requires<list<Predicate> preds> {
152 list<Predicate> Predicates = preds;
155 /// ops definition - This is just a simple marker used to identify the operands
156 /// list for an instruction. This should be used like this:
157 /// (ops R32:$dst, R32:$src) or something similar.
160 /// variable_ops definition - Mark this instruction as taking a variable number
164 /// Operand Types - These provide the built-in operand types that may be used
165 /// by a target. Targets can optionally provide their own operand types as
166 /// needed, though this should not be needed for RISC targets.
167 class Operand<ValueType ty> {
169 string PrintMethod = "printOperand";
170 int NumMIOperands = 1;
171 dag MIOperandInfo = (ops);
174 def i1imm : Operand<i1>;
175 def i8imm : Operand<i8>;
176 def i16imm : Operand<i16>;
177 def i32imm : Operand<i32>;
178 def i64imm : Operand<i64>;
180 // InstrInfo - This class should only be instantiated once to provide parameters
181 // which are global to the the target machine.
184 // If the target wants to associate some target-specific information with each
185 // instruction, it should provide these two lists to indicate how to assemble
186 // the target specific information into the 32 bits available.
188 list<string> TSFlagsFields = [];
189 list<int> TSFlagsShifts = [];
191 // Target can specify its instructions in either big or little-endian formats.
192 // For instance, while both Sparc and PowerPC are big-endian platforms, the
193 // Sparc manual specifies its instructions in the format [31..0] (big), while
194 // PowerPC specifies them using the format [0..31] (little).
195 bit isLittleEndianEncoding = 0;
198 // Standard Instructions.
199 def PHI : Instruction {
200 let OperandList = (ops variable_ops);
201 let AsmString = "PHINODE";
203 def INLINEASM : Instruction {
204 let OperandList = (ops variable_ops);
208 //===----------------------------------------------------------------------===//
209 // AsmWriter - This class can be implemented by targets that need to customize
210 // the format of the .s file writer.
212 // Subtargets can have multiple different asmwriters (e.g. AT&T vs Intel syntax
213 // on X86 for example).
216 // AsmWriterClassName - This specifies the suffix to use for the asmwriter
217 // class. Generated AsmWriter classes are always prefixed with the target
219 string AsmWriterClassName = "AsmPrinter";
221 // InstFormatName - AsmWriters can specify the name of the format string to
222 // print instructions with.
223 string InstFormatName = "AsmString";
225 // Variant - AsmWriters can be of multiple different variants. Variants are
226 // used to support targets that need to emit assembly code in ways that are
227 // mostly the same for different targets, but have minor differences in
228 // syntax. If the asmstring contains {|} characters in them, this integer
229 // will specify which alternative to use. For example "{x|y|z}" with Variant
230 // == 1, will expand to "y".
233 def DefaultAsmWriter : AsmWriter;
236 //===----------------------------------------------------------------------===//
237 // Target - This class contains the "global" target information
240 // CalleeSavedRegisters - As you might guess, this is a list of the callee
241 // saved registers for a target.
242 list<Register> CalleeSavedRegisters = [];
244 // PointerType - Specify the value type to be used to represent pointers in
245 // this target. Typically this is an i32 or i64 type.
246 ValueType PointerType;
248 // InstructionSet - Instruction set description for this target.
249 InstrInfo InstructionSet;
251 // AssemblyWriters - The AsmWriter instances available for this target.
252 list<AsmWriter> AssemblyWriters = [DefaultAsmWriter];
255 //===----------------------------------------------------------------------===//
256 // SubtargetFeature - A characteristic of the chip set.
258 class SubtargetFeature<string n, string a, string v, string d> {
259 // Name - Feature name. Used by command line (-mattr=) to determine the
260 // appropriate target chip.
264 // Attribute - Attribute to be set by feature.
266 string Attribute = a;
268 // Value - Value the attribute to be set to by feature.
272 // Desc - Feature description. Used by command line (-mattr=) to display help
278 //===----------------------------------------------------------------------===//
279 // Processor chip sets - These values represent each of the chip sets supported
280 // by the scheduler. Each Processor definition requires corresponding
281 // instruction itineraries.
283 class Processor<string n, ProcessorItineraries pi, list<SubtargetFeature> f> {
284 // Name - Chip set name. Used by command line (-mcpu=) to determine the
285 // appropriate target chip.
289 // ProcItin - The scheduling information for the target processor.
291 ProcessorItineraries ProcItin = pi;
293 // Features - list of
294 list<SubtargetFeature> Features = f;
297 //===----------------------------------------------------------------------===//
298 // Pull in the common support for DAG isel generation
300 include "../TargetSelectionDAG.td"