Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 1 | // Copyright 2014 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #ifndef V8_TYPES_H_ |
| 6 | #define V8_TYPES_H_ |
| 7 | |
| 8 | #include "src/conversions.h" |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 9 | #include "src/handles.h" |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 10 | #include "src/objects.h" |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 11 | #include "src/ostreams.h" |
| 12 | |
| 13 | namespace v8 { |
| 14 | namespace internal { |
| 15 | |
| 16 | // SUMMARY |
| 17 | // |
| 18 | // A simple type system for compiler-internal use. It is based entirely on |
| 19 | // union types, and all subtyping hence amounts to set inclusion. Besides the |
| 20 | // obvious primitive types and some predefined unions, the type language also |
| 21 | // can express class types (a.k.a. specific maps) and singleton types (i.e., |
| 22 | // concrete constants). |
| 23 | // |
| 24 | // Types consist of two dimensions: semantic (value range) and representation. |
| 25 | // Both are related through subtyping. |
| 26 | // |
| 27 | // |
| 28 | // SEMANTIC DIMENSION |
| 29 | // |
| 30 | // The following equations and inequations hold for the semantic axis: |
| 31 | // |
| 32 | // None <= T |
| 33 | // T <= Any |
| 34 | // |
| 35 | // Number = Signed32 \/ Unsigned32 \/ Double |
| 36 | // Smi <= Signed32 |
| 37 | // Name = String \/ Symbol |
| 38 | // UniqueName = InternalizedString \/ Symbol |
| 39 | // InternalizedString < String |
| 40 | // |
| 41 | // Receiver = Object \/ Proxy |
| 42 | // Array < Object |
| 43 | // Function < Object |
| 44 | // RegExp < Object |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 45 | // OtherUndetectable < Object |
| 46 | // DetectableReceiver = Receiver - OtherUndetectable |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 47 | // |
| 48 | // Class(map) < T iff instance_type(map) < T |
| 49 | // Constant(x) < T iff instance_type(map(x)) < T |
| 50 | // Array(T) < Array |
| 51 | // Function(R, S, T0, T1, ...) < Function |
| 52 | // Context(T) < Internal |
| 53 | // |
| 54 | // Both structural Array and Function types are invariant in all parameters; |
| 55 | // relaxing this would make Union and Intersect operations more involved. |
| 56 | // There is no subtyping relation between Array, Function, or Context types |
| 57 | // and respective Constant types, since these types cannot be reconstructed |
| 58 | // for arbitrary heap values. |
| 59 | // Note also that Constant(x) < Class(map(x)) does _not_ hold, since x's map can |
| 60 | // change! (Its instance type cannot, however.) |
| 61 | // TODO(rossberg): the latter is not currently true for proxies, because of fix, |
| 62 | // but will hold once we implement direct proxies. |
| 63 | // However, we also define a 'temporal' variant of the subtyping relation that |
| 64 | // considers the _current_ state only, i.e., Constant(x) <_now Class(map(x)). |
| 65 | // |
| 66 | // |
| 67 | // REPRESENTATIONAL DIMENSION |
| 68 | // |
| 69 | // For the representation axis, the following holds: |
| 70 | // |
| 71 | // None <= R |
| 72 | // R <= Any |
| 73 | // |
| 74 | // UntaggedInt = UntaggedInt1 \/ UntaggedInt8 \/ |
| 75 | // UntaggedInt16 \/ UntaggedInt32 |
| 76 | // UntaggedFloat = UntaggedFloat32 \/ UntaggedFloat64 |
| 77 | // UntaggedNumber = UntaggedInt \/ UntaggedFloat |
| 78 | // Untagged = UntaggedNumber \/ UntaggedPtr |
| 79 | // Tagged = TaggedInt \/ TaggedPtr |
| 80 | // |
| 81 | // Subtyping relates the two dimensions, for example: |
| 82 | // |
| 83 | // Number <= Tagged \/ UntaggedNumber |
| 84 | // Object <= TaggedPtr \/ UntaggedPtr |
| 85 | // |
| 86 | // That holds because the semantic type constructors defined by the API create |
| 87 | // types that allow for all possible representations, and dually, the ones for |
| 88 | // representation types initially include all semantic ranges. Representations |
| 89 | // can then e.g. be narrowed for a given semantic type using intersection: |
| 90 | // |
| 91 | // SignedSmall /\ TaggedInt (a 'smi') |
| 92 | // Number /\ TaggedPtr (a heap number) |
| 93 | // |
| 94 | // |
| 95 | // RANGE TYPES |
| 96 | // |
| 97 | // A range type represents a continuous integer interval by its minimum and |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 98 | // maximum value. Either value may be an infinity, in which case that infinity |
| 99 | // itself is also included in the range. A range never contains NaN or -0. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 100 | // |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 101 | // If a value v happens to be an integer n, then Constant(v) is considered a |
| 102 | // subtype of Range(n, n) (and therefore also a subtype of any larger range). |
| 103 | // In order to avoid large unions, however, it is usually a good idea to use |
| 104 | // Range rather than Constant. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 105 | // |
| 106 | // |
| 107 | // PREDICATES |
| 108 | // |
| 109 | // There are two main functions for testing types: |
| 110 | // |
| 111 | // T1->Is(T2) -- tests whether T1 is included in T2 (i.e., T1 <= T2) |
| 112 | // T1->Maybe(T2) -- tests whether T1 and T2 overlap (i.e., T1 /\ T2 =/= 0) |
| 113 | // |
| 114 | // Typically, the former is to be used to select representations (e.g., via |
| 115 | // T->Is(SignedSmall())), and the latter to check whether a specific case needs |
| 116 | // handling (e.g., via T->Maybe(Number())). |
| 117 | // |
| 118 | // There is no functionality to discover whether a type is a leaf in the |
| 119 | // lattice. That is intentional. It should always be possible to refine the |
| 120 | // lattice (e.g., splitting up number types further) without invalidating any |
| 121 | // existing assumptions or tests. |
| 122 | // Consequently, do not normally use Equals for type tests, always use Is! |
| 123 | // |
| 124 | // The NowIs operator implements state-sensitive subtying, as described above. |
| 125 | // Any compilation decision based on such temporary properties requires runtime |
| 126 | // guarding! |
| 127 | // |
| 128 | // |
| 129 | // PROPERTIES |
| 130 | // |
| 131 | // Various formal properties hold for constructors, operators, and predicates |
| 132 | // over types. For example, constructors are injective and subtyping is a |
| 133 | // complete partial order. |
| 134 | // |
| 135 | // See test/cctest/test-types.cc for a comprehensive executable specification, |
| 136 | // especially with respect to the properties of the more exotic 'temporal' |
| 137 | // constructors and predicates (those prefixed 'Now'). |
| 138 | // |
| 139 | // |
| 140 | // IMPLEMENTATION |
| 141 | // |
| 142 | // Internally, all 'primitive' types, and their unions, are represented as |
| 143 | // bitsets. Bit 0 is reserved for tagging. Class is a heap pointer to the |
| 144 | // respective map. Only structured types require allocation. |
| 145 | // Note that the bitset representation is closed under both Union and Intersect. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 146 | |
| 147 | |
| 148 | // ----------------------------------------------------------------------------- |
| 149 | // Values for bitset types |
| 150 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 151 | // clang-format off |
| 152 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 153 | #define MASK_BITSET_TYPE_LIST(V) \ |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 154 | V(Representation, 0xffc00000u) \ |
| 155 | V(Semantic, 0x003ffffeu) |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 156 | |
| 157 | #define REPRESENTATION(k) ((k) & BitsetType::kRepresentation) |
| 158 | #define SEMANTIC(k) ((k) & BitsetType::kSemantic) |
| 159 | |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 160 | #define REPRESENTATION_BITSET_TYPE_LIST(V) \ |
| 161 | V(None, 0) \ |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 162 | V(UntaggedBit, 1u << 22 | kSemantic) \ |
| 163 | V(UntaggedIntegral8, 1u << 23 | kSemantic) \ |
| 164 | V(UntaggedIntegral16, 1u << 24 | kSemantic) \ |
| 165 | V(UntaggedIntegral32, 1u << 25 | kSemantic) \ |
| 166 | V(UntaggedFloat32, 1u << 26 | kSemantic) \ |
| 167 | V(UntaggedFloat64, 1u << 27 | kSemantic) \ |
| 168 | V(UntaggedSimd128, 1u << 28 | kSemantic) \ |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 169 | V(UntaggedPointer, 1u << 29 | kSemantic) \ |
| 170 | V(TaggedSigned, 1u << 30 | kSemantic) \ |
| 171 | V(TaggedPointer, 1u << 31 | kSemantic) \ |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 172 | \ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 173 | V(UntaggedIntegral, kUntaggedBit | kUntaggedIntegral8 | \ |
| 174 | kUntaggedIntegral16 | kUntaggedIntegral32) \ |
| 175 | V(UntaggedFloat, kUntaggedFloat32 | kUntaggedFloat64) \ |
| 176 | V(UntaggedNumber, kUntaggedIntegral | kUntaggedFloat) \ |
| 177 | V(Untagged, kUntaggedNumber | kUntaggedPointer) \ |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 178 | V(Tagged, kTaggedSigned | kTaggedPointer) |
| 179 | |
| 180 | #define INTERNAL_BITSET_TYPE_LIST(V) \ |
| 181 | V(OtherUnsigned31, 1u << 1 | REPRESENTATION(kTagged | kUntaggedNumber)) \ |
| 182 | V(OtherUnsigned32, 1u << 2 | REPRESENTATION(kTagged | kUntaggedNumber)) \ |
| 183 | V(OtherSigned32, 1u << 3 | REPRESENTATION(kTagged | kUntaggedNumber)) \ |
| 184 | V(OtherNumber, 1u << 4 | REPRESENTATION(kTagged | kUntaggedNumber)) |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 185 | |
| 186 | #define SEMANTIC_BITSET_TYPE_LIST(V) \ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 187 | V(Negative31, 1u << 5 | REPRESENTATION(kTagged | kUntaggedNumber)) \ |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 188 | V(Null, 1u << 6 | REPRESENTATION(kTaggedPointer)) \ |
| 189 | V(Undefined, 1u << 7 | REPRESENTATION(kTaggedPointer)) \ |
| 190 | V(Boolean, 1u << 8 | REPRESENTATION(kTaggedPointer)) \ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 191 | V(Unsigned30, 1u << 9 | REPRESENTATION(kTagged | kUntaggedNumber)) \ |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 192 | V(MinusZero, 1u << 10 | REPRESENTATION(kTagged | kUntaggedNumber)) \ |
| 193 | V(NaN, 1u << 11 | REPRESENTATION(kTagged | kUntaggedNumber)) \ |
| 194 | V(Symbol, 1u << 12 | REPRESENTATION(kTaggedPointer)) \ |
| 195 | V(InternalizedString, 1u << 13 | REPRESENTATION(kTaggedPointer)) \ |
| 196 | V(OtherString, 1u << 14 | REPRESENTATION(kTaggedPointer)) \ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 197 | V(Simd, 1u << 15 | REPRESENTATION(kTaggedPointer)) \ |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 198 | V(OtherObject, 1u << 17 | REPRESENTATION(kTaggedPointer)) \ |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 199 | V(OtherUndetectable, 1u << 16 | REPRESENTATION(kTaggedPointer)) \ |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 200 | V(Proxy, 1u << 18 | REPRESENTATION(kTaggedPointer)) \ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 201 | V(Function, 1u << 19 | REPRESENTATION(kTaggedPointer)) \ |
| 202 | V(Internal, 1u << 20 | REPRESENTATION(kTagged | kUntagged)) \ |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 203 | \ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 204 | V(Signed31, kUnsigned30 | kNegative31) \ |
| 205 | V(Signed32, kSigned31 | kOtherUnsigned31 | kOtherSigned32) \ |
| 206 | V(Negative32, kNegative31 | kOtherSigned32) \ |
| 207 | V(Unsigned31, kUnsigned30 | kOtherUnsigned31) \ |
| 208 | V(Unsigned32, kUnsigned30 | kOtherUnsigned31 | \ |
| 209 | kOtherUnsigned32) \ |
| 210 | V(Integral32, kSigned32 | kUnsigned32) \ |
| 211 | V(PlainNumber, kIntegral32 | kOtherNumber) \ |
| 212 | V(OrderedNumber, kPlainNumber | kMinusZero) \ |
| 213 | V(MinusZeroOrNaN, kMinusZero | kNaN) \ |
| 214 | V(Number, kOrderedNumber | kNaN) \ |
| 215 | V(String, kInternalizedString | kOtherString) \ |
| 216 | V(UniqueName, kSymbol | kInternalizedString) \ |
| 217 | V(Name, kSymbol | kString) \ |
| 218 | V(BooleanOrNumber, kBoolean | kNumber) \ |
| 219 | V(BooleanOrNullOrUndefined, kBoolean | kNull | kUndefined) \ |
| 220 | V(NullOrUndefined, kNull | kUndefined) \ |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 221 | V(Undetectable, kNullOrUndefined | kOtherUndetectable) \ |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 222 | V(NumberOrOddball, kNumber | kNullOrUndefined | kBoolean) \ |
| 223 | V(NumberOrSimdOrString, kNumber | kSimd | kString) \ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 224 | V(NumberOrString, kNumber | kString) \ |
| 225 | V(NumberOrUndefined, kNumber | kUndefined) \ |
| 226 | V(PlainPrimitive, kNumberOrString | kBoolean | kNullOrUndefined) \ |
| 227 | V(Primitive, kSymbol | kSimd | kPlainPrimitive) \ |
| 228 | V(DetectableReceiver, kFunction | kOtherObject | kProxy) \ |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 229 | V(Object, kFunction | kOtherObject | kOtherUndetectable) \ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 230 | V(Receiver, kObject | kProxy) \ |
| 231 | V(StringOrReceiver, kString | kReceiver) \ |
| 232 | V(Unique, kBoolean | kUniqueName | kNull | kUndefined | \ |
| 233 | kReceiver) \ |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 234 | V(NonInternal, kPrimitive | kReceiver) \ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 235 | V(NonNumber, kUnique | kString | kInternal) \ |
| 236 | V(Any, 0xfffffffeu) |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 237 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 238 | // clang-format on |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 239 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 240 | /* |
| 241 | * The following diagrams show how integers (in the mathematical sense) are |
| 242 | * divided among the different atomic numerical types. |
| 243 | * |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 244 | * ON OS32 N31 U30 OU31 OU32 ON |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 245 | * ______[_______[_______[_______[_______[_______[_______ |
| 246 | * -2^31 -2^30 0 2^30 2^31 2^32 |
| 247 | * |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 248 | * E.g., OtherUnsigned32 (OU32) covers all integers from 2^31 to 2^32-1. |
| 249 | * |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 250 | * Some of the atomic numerical bitsets are internal only (see |
| 251 | * INTERNAL_BITSET_TYPE_LIST). To a types user, they should only occur in |
| 252 | * union with certain other bitsets. For instance, OtherNumber should only |
| 253 | * occur as part of PlainNumber. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 254 | */ |
| 255 | |
| 256 | #define PROPER_BITSET_TYPE_LIST(V) \ |
| 257 | REPRESENTATION_BITSET_TYPE_LIST(V) \ |
| 258 | SEMANTIC_BITSET_TYPE_LIST(V) |
| 259 | |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 260 | #define BITSET_TYPE_LIST(V) \ |
| 261 | MASK_BITSET_TYPE_LIST(V) \ |
| 262 | REPRESENTATION_BITSET_TYPE_LIST(V) \ |
| 263 | INTERNAL_BITSET_TYPE_LIST(V) \ |
| 264 | SEMANTIC_BITSET_TYPE_LIST(V) |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 265 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 266 | class Type; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 267 | |
| 268 | // ----------------------------------------------------------------------------- |
| 269 | // Bitset types (internal). |
| 270 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 271 | class BitsetType { |
| 272 | public: |
| 273 | typedef uint32_t bitset; // Internal |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 274 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 275 | enum : uint32_t { |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 276 | #define DECLARE_TYPE(type, value) k##type = (value), |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 277 | BITSET_TYPE_LIST(DECLARE_TYPE) |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 278 | #undef DECLARE_TYPE |
| 279 | kUnusedEOL = 0 |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 280 | }; |
| 281 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 282 | static bitset SignedSmall(); |
| 283 | static bitset UnsignedSmall(); |
| 284 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 285 | bitset Bitset() { |
| 286 | return static_cast<bitset>(reinterpret_cast<uintptr_t>(this) ^ 1u); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 287 | } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 288 | |
| 289 | static bool IsInhabited(bitset bits) { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 290 | return SEMANTIC(bits) != kNone && REPRESENTATION(bits) != kNone; |
| 291 | } |
| 292 | |
| 293 | static bool SemanticIsInhabited(bitset bits) { |
| 294 | return SEMANTIC(bits) != kNone; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 295 | } |
| 296 | |
| 297 | static bool Is(bitset bits1, bitset bits2) { |
| 298 | return (bits1 | bits2) == bits2; |
| 299 | } |
| 300 | |
| 301 | static double Min(bitset); |
| 302 | static double Max(bitset); |
| 303 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 304 | static bitset Glb(Type* type); // greatest lower bound that's a bitset |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 305 | static bitset Glb(double min, double max); |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 306 | static bitset Lub(Type* type); // least upper bound that's a bitset |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 307 | static bitset Lub(i::Map* map); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 308 | static bitset Lub(i::Object* value); |
| 309 | static bitset Lub(double value); |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 310 | static bitset Lub(double min, double max); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 311 | static bitset ExpandInternals(bitset bits); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 312 | |
| 313 | static const char* Name(bitset); |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 314 | static void Print(std::ostream& os, bitset); // NOLINT |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 315 | #ifdef DEBUG |
| 316 | static void Print(bitset); |
| 317 | #endif |
| 318 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 319 | static bitset NumberBits(bitset bits); |
| 320 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 321 | static bool IsBitset(Type* type) { |
| 322 | return reinterpret_cast<uintptr_t>(type) & 1; |
| 323 | } |
| 324 | |
| 325 | static Type* NewForTesting(bitset bits) { return New(bits); } |
| 326 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 327 | private: |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 328 | friend class Type; |
| 329 | |
| 330 | static Type* New(bitset bits) { |
| 331 | return reinterpret_cast<Type*>(static_cast<uintptr_t>(bits | 1u)); |
| 332 | } |
| 333 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 334 | struct Boundary { |
| 335 | bitset internal; |
| 336 | bitset external; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 337 | double min; |
| 338 | }; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 339 | static const Boundary BoundariesArray[]; |
| 340 | static inline const Boundary* Boundaries(); |
| 341 | static inline size_t BoundariesSize(); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 342 | }; |
| 343 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 344 | // ----------------------------------------------------------------------------- |
| 345 | // Superclass for non-bitset types (internal). |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 346 | class TypeBase { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 347 | protected: |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 348 | friend class Type; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 349 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 350 | enum Kind { |
| 351 | kClass, |
| 352 | kConstant, |
| 353 | kContext, |
| 354 | kArray, |
| 355 | kFunction, |
| 356 | kTuple, |
| 357 | kUnion, |
| 358 | kRange |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 359 | }; |
| 360 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 361 | Kind kind() const { return kind_; } |
| 362 | explicit TypeBase(Kind kind) : kind_(kind) {} |
| 363 | |
| 364 | static bool IsKind(Type* type, Kind kind) { |
| 365 | if (BitsetType::IsBitset(type)) return false; |
| 366 | TypeBase* base = reinterpret_cast<TypeBase*>(type); |
| 367 | return base->kind() == kind; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 368 | } |
| 369 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 370 | // The hacky conversion to/from Type*. |
| 371 | static Type* AsType(TypeBase* type) { return reinterpret_cast<Type*>(type); } |
| 372 | static TypeBase* FromType(Type* type) { |
| 373 | return reinterpret_cast<TypeBase*>(type); |
| 374 | } |
| 375 | |
| 376 | private: |
| 377 | Kind kind_; |
| 378 | }; |
| 379 | |
| 380 | // ----------------------------------------------------------------------------- |
| 381 | // Class types. |
| 382 | |
| 383 | class ClassType : public TypeBase { |
| 384 | public: |
| 385 | i::Handle<i::Map> Map() { return map_; } |
| 386 | |
| 387 | private: |
| 388 | friend class Type; |
| 389 | friend class BitsetType; |
| 390 | |
| 391 | static Type* New(i::Handle<i::Map> map, Zone* zone) { |
| 392 | return AsType(new (zone->New(sizeof(ClassType))) |
| 393 | ClassType(BitsetType::Lub(*map), map)); |
| 394 | } |
| 395 | |
| 396 | static ClassType* cast(Type* type) { |
| 397 | DCHECK(IsKind(type, kClass)); |
| 398 | return static_cast<ClassType*>(FromType(type)); |
| 399 | } |
| 400 | |
| 401 | ClassType(BitsetType::bitset bitset, i::Handle<i::Map> map) |
| 402 | : TypeBase(kClass), bitset_(bitset), map_(map) {} |
| 403 | |
| 404 | BitsetType::bitset Lub() { return bitset_; } |
| 405 | |
| 406 | BitsetType::bitset bitset_; |
| 407 | Handle<i::Map> map_; |
| 408 | }; |
| 409 | |
| 410 | // ----------------------------------------------------------------------------- |
| 411 | // Constant types. |
| 412 | |
| 413 | class ConstantType : public TypeBase { |
| 414 | public: |
| 415 | i::Handle<i::Object> Value() { return object_; } |
| 416 | |
| 417 | private: |
| 418 | friend class Type; |
| 419 | friend class BitsetType; |
| 420 | |
| 421 | static Type* New(i::Handle<i::Object> value, Zone* zone) { |
| 422 | BitsetType::bitset bitset = BitsetType::Lub(*value); |
| 423 | return AsType(new (zone->New(sizeof(ConstantType))) |
| 424 | ConstantType(bitset, value)); |
| 425 | } |
| 426 | |
| 427 | static ConstantType* cast(Type* type) { |
| 428 | DCHECK(IsKind(type, kConstant)); |
| 429 | return static_cast<ConstantType*>(FromType(type)); |
| 430 | } |
| 431 | |
| 432 | ConstantType(BitsetType::bitset bitset, i::Handle<i::Object> object) |
| 433 | : TypeBase(kConstant), bitset_(bitset), object_(object) {} |
| 434 | |
| 435 | BitsetType::bitset Lub() { return bitset_; } |
| 436 | |
| 437 | BitsetType::bitset bitset_; |
| 438 | Handle<i::Object> object_; |
| 439 | }; |
| 440 | // TODO(neis): Also cache value if numerical. |
| 441 | // TODO(neis): Allow restricting the representation. |
| 442 | |
| 443 | // ----------------------------------------------------------------------------- |
| 444 | // Range types. |
| 445 | |
| 446 | class RangeType : public TypeBase { |
| 447 | public: |
| 448 | struct Limits { |
| 449 | double min; |
| 450 | double max; |
| 451 | Limits(double min, double max) : min(min), max(max) {} |
| 452 | explicit Limits(RangeType* range) : min(range->Min()), max(range->Max()) {} |
| 453 | bool IsEmpty(); |
| 454 | static Limits Empty() { return Limits(1, 0); } |
| 455 | static Limits Intersect(Limits lhs, Limits rhs); |
| 456 | static Limits Union(Limits lhs, Limits rhs); |
| 457 | }; |
| 458 | |
| 459 | double Min() { return limits_.min; } |
| 460 | double Max() { return limits_.max; } |
| 461 | |
| 462 | private: |
| 463 | friend class Type; |
| 464 | friend class BitsetType; |
| 465 | friend class UnionType; |
| 466 | |
| 467 | static Type* New(double min, double max, BitsetType::bitset representation, |
| 468 | Zone* zone) { |
| 469 | return New(Limits(min, max), representation, zone); |
| 470 | } |
| 471 | |
| 472 | static bool IsInteger(double x) { |
| 473 | return nearbyint(x) == x && !i::IsMinusZero(x); // Allows for infinities. |
| 474 | } |
| 475 | |
| 476 | static Type* New(Limits lim, BitsetType::bitset representation, Zone* zone) { |
| 477 | DCHECK(IsInteger(lim.min) && IsInteger(lim.max)); |
| 478 | DCHECK(lim.min <= lim.max); |
| 479 | DCHECK(REPRESENTATION(representation) == representation); |
| 480 | BitsetType::bitset bits = |
| 481 | SEMANTIC(BitsetType::Lub(lim.min, lim.max)) | representation; |
| 482 | |
| 483 | return AsType(new (zone->New(sizeof(RangeType))) RangeType(bits, lim)); |
| 484 | } |
| 485 | |
| 486 | static RangeType* cast(Type* type) { |
| 487 | DCHECK(IsKind(type, kRange)); |
| 488 | return static_cast<RangeType*>(FromType(type)); |
| 489 | } |
| 490 | |
| 491 | RangeType(BitsetType::bitset bitset, Limits limits) |
| 492 | : TypeBase(kRange), bitset_(bitset), limits_(limits) {} |
| 493 | |
| 494 | BitsetType::bitset Lub() { return bitset_; } |
| 495 | |
| 496 | BitsetType::bitset bitset_; |
| 497 | Limits limits_; |
| 498 | }; |
| 499 | |
| 500 | // ----------------------------------------------------------------------------- |
| 501 | // Context types. |
| 502 | |
| 503 | class ContextType : public TypeBase { |
| 504 | public: |
| 505 | Type* Outer() { return outer_; } |
| 506 | |
| 507 | private: |
| 508 | friend class Type; |
| 509 | |
| 510 | static Type* New(Type* outer, Zone* zone) { |
| 511 | return AsType(new (zone->New(sizeof(ContextType))) ContextType(outer)); |
| 512 | } |
| 513 | |
| 514 | static ContextType* cast(Type* type) { |
| 515 | DCHECK(IsKind(type, kContext)); |
| 516 | return static_cast<ContextType*>(FromType(type)); |
| 517 | } |
| 518 | |
| 519 | explicit ContextType(Type* outer) : TypeBase(kContext), outer_(outer) {} |
| 520 | |
| 521 | Type* outer_; |
| 522 | }; |
| 523 | |
| 524 | // ----------------------------------------------------------------------------- |
| 525 | // Array types. |
| 526 | |
| 527 | class ArrayType : public TypeBase { |
| 528 | public: |
| 529 | Type* Element() { return element_; } |
| 530 | |
| 531 | private: |
| 532 | friend class Type; |
| 533 | |
| 534 | explicit ArrayType(Type* element) : TypeBase(kArray), element_(element) {} |
| 535 | |
| 536 | static Type* New(Type* element, Zone* zone) { |
| 537 | return AsType(new (zone->New(sizeof(ArrayType))) ArrayType(element)); |
| 538 | } |
| 539 | |
| 540 | static ArrayType* cast(Type* type) { |
| 541 | DCHECK(IsKind(type, kArray)); |
| 542 | return static_cast<ArrayType*>(FromType(type)); |
| 543 | } |
| 544 | |
| 545 | Type* element_; |
| 546 | }; |
| 547 | |
| 548 | // ----------------------------------------------------------------------------- |
| 549 | // Superclass for types with variable number of type fields. |
| 550 | class StructuralType : public TypeBase { |
| 551 | public: |
| 552 | int LengthForTesting() { return Length(); } |
| 553 | |
| 554 | protected: |
| 555 | friend class Type; |
| 556 | |
| 557 | int Length() { return length_; } |
| 558 | |
| 559 | Type* Get(int i) { |
| 560 | DCHECK(0 <= i && i < this->Length()); |
| 561 | return elements_[i]; |
| 562 | } |
| 563 | |
| 564 | void Set(int i, Type* type) { |
| 565 | DCHECK(0 <= i && i < this->Length()); |
| 566 | elements_[i] = type; |
| 567 | } |
| 568 | |
| 569 | void Shrink(int length) { |
| 570 | DCHECK(2 <= length && length <= this->Length()); |
| 571 | length_ = length; |
| 572 | } |
| 573 | |
| 574 | StructuralType(Kind kind, int length, i::Zone* zone) |
| 575 | : TypeBase(kind), length_(length) { |
| 576 | elements_ = reinterpret_cast<Type**>(zone->New(sizeof(Type*) * length)); |
| 577 | } |
| 578 | |
| 579 | private: |
| 580 | int length_; |
| 581 | Type** elements_; |
| 582 | }; |
| 583 | |
| 584 | // ----------------------------------------------------------------------------- |
| 585 | // Function types. |
| 586 | |
| 587 | class FunctionType : public StructuralType { |
| 588 | public: |
| 589 | int Arity() { return this->Length() - 2; } |
| 590 | Type* Result() { return this->Get(0); } |
| 591 | Type* Receiver() { return this->Get(1); } |
| 592 | Type* Parameter(int i) { return this->Get(2 + i); } |
| 593 | |
| 594 | void InitParameter(int i, Type* type) { this->Set(2 + i, type); } |
| 595 | |
| 596 | private: |
| 597 | friend class Type; |
| 598 | |
| 599 | FunctionType(Type* result, Type* receiver, int arity, Zone* zone) |
| 600 | : StructuralType(kFunction, 2 + arity, zone) { |
| 601 | Set(0, result); |
| 602 | Set(1, receiver); |
| 603 | } |
| 604 | |
| 605 | static Type* New(Type* result, Type* receiver, int arity, Zone* zone) { |
| 606 | return AsType(new (zone->New(sizeof(FunctionType))) |
| 607 | FunctionType(result, receiver, arity, zone)); |
| 608 | } |
| 609 | |
| 610 | static FunctionType* cast(Type* type) { |
| 611 | DCHECK(IsKind(type, kFunction)); |
| 612 | return static_cast<FunctionType*>(FromType(type)); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 613 | } |
| 614 | }; |
| 615 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 616 | // ----------------------------------------------------------------------------- |
| 617 | // Tuple types. |
| 618 | |
| 619 | class TupleType : public StructuralType { |
| 620 | public: |
| 621 | int Arity() { return this->Length(); } |
| 622 | Type* Element(int i) { return this->Get(i); } |
| 623 | |
| 624 | void InitElement(int i, Type* type) { this->Set(i, type); } |
| 625 | |
| 626 | private: |
| 627 | friend class Type; |
| 628 | |
| 629 | TupleType(int length, Zone* zone) : StructuralType(kTuple, length, zone) {} |
| 630 | |
| 631 | static Type* New(int length, Zone* zone) { |
| 632 | return AsType(new (zone->New(sizeof(TupleType))) TupleType(length, zone)); |
| 633 | } |
| 634 | |
| 635 | static TupleType* cast(Type* type) { |
| 636 | DCHECK(IsKind(type, kTuple)); |
| 637 | return static_cast<TupleType*>(FromType(type)); |
| 638 | } |
| 639 | }; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 640 | |
| 641 | // ----------------------------------------------------------------------------- |
| 642 | // Union types (internal). |
| 643 | // A union is a structured type with the following invariants: |
| 644 | // - its length is at least 2 |
| 645 | // - at most one field is a bitset, and it must go into index 0 |
| 646 | // - no field is a union |
| 647 | // - no field is a subtype of any other field |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 648 | class UnionType : public StructuralType { |
| 649 | private: |
| 650 | friend Type; |
| 651 | friend BitsetType; |
| 652 | |
| 653 | UnionType(int length, Zone* zone) : StructuralType(kUnion, length, zone) {} |
| 654 | |
| 655 | static Type* New(int length, Zone* zone) { |
| 656 | return AsType(new (zone->New(sizeof(UnionType))) UnionType(length, zone)); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 657 | } |
| 658 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 659 | static UnionType* cast(Type* type) { |
| 660 | DCHECK(IsKind(type, kUnion)); |
| 661 | return static_cast<UnionType*>(FromType(type)); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 662 | } |
| 663 | |
| 664 | bool Wellformed(); |
| 665 | }; |
| 666 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 667 | class Type { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 668 | public: |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 669 | typedef BitsetType::bitset bitset; // Internal |
| 670 | |
| 671 | // Constructors. |
| 672 | #define DEFINE_TYPE_CONSTRUCTOR(type, value) \ |
| 673 | static Type* type() { return BitsetType::New(BitsetType::k##type); } |
| 674 | PROPER_BITSET_TYPE_LIST(DEFINE_TYPE_CONSTRUCTOR) |
| 675 | #undef DEFINE_TYPE_CONSTRUCTOR |
| 676 | |
| 677 | static Type* SignedSmall() { |
| 678 | return BitsetType::New(BitsetType::SignedSmall()); |
| 679 | } |
| 680 | static Type* UnsignedSmall() { |
| 681 | return BitsetType::New(BitsetType::UnsignedSmall()); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 682 | } |
| 683 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 684 | static Type* Class(i::Handle<i::Map> map, Zone* zone) { |
| 685 | return ClassType::New(map, zone); |
| 686 | } |
| 687 | static Type* Constant(i::Handle<i::Object> value, Zone* zone) { |
| 688 | return ConstantType::New(value, zone); |
| 689 | } |
| 690 | static Type* Range(double min, double max, Zone* zone) { |
| 691 | return RangeType::New(min, max, REPRESENTATION(BitsetType::kTagged | |
| 692 | BitsetType::kUntaggedNumber), |
| 693 | zone); |
| 694 | } |
| 695 | static Type* Context(Type* outer, Zone* zone) { |
| 696 | return ContextType::New(outer, zone); |
| 697 | } |
| 698 | static Type* Array(Type* element, Zone* zone) { |
| 699 | return ArrayType::New(element, zone); |
| 700 | } |
| 701 | static Type* Function(Type* result, Type* receiver, int arity, Zone* zone) { |
| 702 | return FunctionType::New(result, receiver, arity, zone); |
| 703 | } |
| 704 | static Type* Function(Type* result, Zone* zone) { |
| 705 | return Function(result, Any(), 0, zone); |
| 706 | } |
| 707 | static Type* Function(Type* result, Type* param0, Zone* zone) { |
| 708 | Type* function = Function(result, Any(), 1, zone); |
| 709 | function->AsFunction()->InitParameter(0, param0); |
| 710 | return function; |
| 711 | } |
| 712 | static Type* Function(Type* result, Type* param0, Type* param1, Zone* zone) { |
| 713 | Type* function = Function(result, Any(), 2, zone); |
| 714 | function->AsFunction()->InitParameter(0, param0); |
| 715 | function->AsFunction()->InitParameter(1, param1); |
| 716 | return function; |
| 717 | } |
| 718 | static Type* Function(Type* result, Type* param0, Type* param1, Type* param2, |
| 719 | Zone* zone) { |
| 720 | Type* function = Function(result, Any(), 3, zone); |
| 721 | function->AsFunction()->InitParameter(0, param0); |
| 722 | function->AsFunction()->InitParameter(1, param1); |
| 723 | function->AsFunction()->InitParameter(2, param2); |
| 724 | return function; |
| 725 | } |
| 726 | static Type* Function(Type* result, int arity, Type** params, Zone* zone) { |
| 727 | Type* function = Function(result, Any(), arity, zone); |
| 728 | for (int i = 0; i < arity; ++i) { |
| 729 | function->AsFunction()->InitParameter(i, params[i]); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 730 | } |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 731 | return function; |
| 732 | } |
| 733 | static Type* Tuple(Type* first, Type* second, Type* third, Zone* zone) { |
| 734 | Type* tuple = TupleType::New(3, zone); |
| 735 | tuple->AsTuple()->InitElement(0, first); |
| 736 | tuple->AsTuple()->InitElement(1, second); |
| 737 | tuple->AsTuple()->InitElement(2, third); |
| 738 | return tuple; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 739 | } |
| 740 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 741 | #define CONSTRUCT_SIMD_TYPE(NAME, Name, name, lane_count, lane_type) \ |
| 742 | static Type* Name(Isolate* isolate, Zone* zone); |
| 743 | SIMD128_TYPES(CONSTRUCT_SIMD_TYPE) |
| 744 | #undef CONSTRUCT_SIMD_TYPE |
| 745 | |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 746 | static Type* Union(Type* type1, Type* type2, Zone* zone); |
| 747 | static Type* Intersect(Type* type1, Type* type2, Zone* zone); |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 748 | |
| 749 | static Type* Of(double value, Zone* zone) { |
| 750 | return BitsetType::New(BitsetType::ExpandInternals(BitsetType::Lub(value))); |
| 751 | } |
| 752 | static Type* Of(i::Object* value, Zone* zone) { |
| 753 | return BitsetType::New(BitsetType::ExpandInternals(BitsetType::Lub(value))); |
| 754 | } |
| 755 | static Type* Of(i::Handle<i::Object> value, Zone* zone) { |
| 756 | return Of(*value, zone); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 757 | } |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 758 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 759 | // Extraction of components. |
| 760 | static Type* Representation(Type* t, Zone* zone); |
| 761 | static Type* Semantic(Type* t, Zone* zone); |
| 762 | |
| 763 | // Predicates. |
| 764 | bool IsInhabited() { return BitsetType::IsInhabited(this->BitsetLub()); } |
| 765 | |
| 766 | bool Is(Type* that) { return this == that || this->SlowIs(that); } |
| 767 | bool Maybe(Type* that); |
| 768 | bool Equals(Type* that) { return this->Is(that) && that->Is(this); } |
| 769 | |
| 770 | // Equivalent to Constant(val)->Is(this), but avoiding allocation. |
| 771 | bool Contains(i::Object* val); |
| 772 | bool Contains(i::Handle<i::Object> val) { return this->Contains(*val); } |
| 773 | |
| 774 | // State-dependent versions of the above that consider subtyping between |
| 775 | // a constant and its map class. |
| 776 | static Type* NowOf(i::Object* value, Zone* zone); |
| 777 | static Type* NowOf(i::Handle<i::Object> value, Zone* zone) { |
| 778 | return NowOf(*value, zone); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 779 | } |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 780 | bool NowIs(Type* that); |
| 781 | bool NowContains(i::Object* val); |
| 782 | bool NowContains(i::Handle<i::Object> val) { return this->NowContains(*val); } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 783 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 784 | bool NowStable(); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 785 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 786 | // Inspection. |
| 787 | bool IsRange() { return IsKind(TypeBase::kRange); } |
| 788 | bool IsClass() { return IsKind(TypeBase::kClass); } |
| 789 | bool IsConstant() { return IsKind(TypeBase::kConstant); } |
| 790 | bool IsContext() { return IsKind(TypeBase::kContext); } |
| 791 | bool IsArray() { return IsKind(TypeBase::kArray); } |
| 792 | bool IsFunction() { return IsKind(TypeBase::kFunction); } |
| 793 | bool IsTuple() { return IsKind(TypeBase::kTuple); } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 794 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 795 | ClassType* AsClass() { return ClassType::cast(this); } |
| 796 | ConstantType* AsConstant() { return ConstantType::cast(this); } |
| 797 | RangeType* AsRange() { return RangeType::cast(this); } |
| 798 | ContextType* AsContext() { return ContextType::cast(this); } |
| 799 | ArrayType* AsArray() { return ArrayType::cast(this); } |
| 800 | FunctionType* AsFunction() { return FunctionType::cast(this); } |
| 801 | TupleType* AsTuple() { return TupleType::cast(this); } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 802 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 803 | // Minimum and maximum of a numeric type. |
| 804 | // These functions do not distinguish between -0 and +0. If the type equals |
| 805 | // kNaN, they return NaN; otherwise kNaN is ignored. Only call these |
| 806 | // functions on subtypes of Number. |
| 807 | double Min(); |
| 808 | double Max(); |
| 809 | |
| 810 | // Extracts a range from the type: if the type is a range or a union |
| 811 | // containing a range, that range is returned; otherwise, NULL is returned. |
| 812 | Type* GetRange(); |
| 813 | |
| 814 | static bool IsInteger(i::Object* x); |
| 815 | static bool IsInteger(double x) { |
| 816 | return nearbyint(x) == x && !i::IsMinusZero(x); // Allows for infinities. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 817 | } |
| 818 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 819 | int NumClasses(); |
| 820 | int NumConstants(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 821 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 822 | template <class T> |
| 823 | class Iterator { |
| 824 | public: |
| 825 | bool Done() const { return index_ < 0; } |
| 826 | i::Handle<T> Current(); |
| 827 | void Advance(); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 828 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 829 | private: |
| 830 | friend class Type; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 831 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 832 | Iterator() : index_(-1) {} |
| 833 | explicit Iterator(Type* type) : type_(type), index_(-1) { Advance(); } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 834 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 835 | inline bool matches(Type* type); |
| 836 | inline Type* get_type(); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 837 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 838 | Type* type_; |
| 839 | int index_; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 840 | }; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 841 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 842 | Iterator<i::Map> Classes() { |
| 843 | if (this->IsBitset()) return Iterator<i::Map>(); |
| 844 | return Iterator<i::Map>(this); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 845 | } |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 846 | Iterator<i::Object> Constants() { |
| 847 | if (this->IsBitset()) return Iterator<i::Object>(); |
| 848 | return Iterator<i::Object>(this); |
| 849 | } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 850 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 851 | // Printing. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 852 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 853 | enum PrintDimension { BOTH_DIMS, SEMANTIC_DIM, REPRESENTATION_DIM }; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 854 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 855 | void PrintTo(std::ostream& os, PrintDimension dim = BOTH_DIMS); // NOLINT |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 856 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 857 | #ifdef DEBUG |
| 858 | void Print(); |
| 859 | #endif |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 860 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 861 | // Helpers for testing. |
| 862 | bool IsBitsetForTesting() { return IsBitset(); } |
| 863 | bool IsUnionForTesting() { return IsUnion(); } |
| 864 | bitset AsBitsetForTesting() { return AsBitset(); } |
| 865 | UnionType* AsUnionForTesting() { return AsUnion(); } |
| 866 | |
| 867 | private: |
| 868 | // Friends. |
| 869 | template <class> |
| 870 | friend class Iterator; |
| 871 | friend BitsetType; |
| 872 | friend UnionType; |
| 873 | |
| 874 | // Internal inspection. |
| 875 | bool IsKind(TypeBase::Kind kind) { return TypeBase::IsKind(this, kind); } |
| 876 | |
| 877 | bool IsNone() { return this == None(); } |
| 878 | bool IsAny() { return this == Any(); } |
| 879 | bool IsBitset() { return BitsetType::IsBitset(this); } |
| 880 | bool IsUnion() { return IsKind(TypeBase::kUnion); } |
| 881 | |
| 882 | bitset AsBitset() { |
| 883 | DCHECK(this->IsBitset()); |
| 884 | return reinterpret_cast<BitsetType*>(this)->Bitset(); |
| 885 | } |
| 886 | UnionType* AsUnion() { return UnionType::cast(this); } |
| 887 | |
| 888 | bitset Representation(); |
| 889 | |
| 890 | // Auxiliary functions. |
| 891 | bool SemanticMaybe(Type* that); |
| 892 | |
| 893 | bitset BitsetGlb() { return BitsetType::Glb(this); } |
| 894 | bitset BitsetLub() { return BitsetType::Lub(this); } |
| 895 | |
| 896 | bool SlowIs(Type* that); |
| 897 | bool SemanticIs(Type* that); |
| 898 | |
| 899 | static bool Overlap(RangeType* lhs, RangeType* rhs); |
| 900 | static bool Contains(RangeType* lhs, RangeType* rhs); |
| 901 | static bool Contains(RangeType* range, ConstantType* constant); |
| 902 | static bool Contains(RangeType* range, i::Object* val); |
| 903 | |
| 904 | static int UpdateRange(Type* type, UnionType* result, int size, Zone* zone); |
| 905 | |
| 906 | static RangeType::Limits IntersectRangeAndBitset(Type* range, Type* bits, |
| 907 | Zone* zone); |
| 908 | static RangeType::Limits ToLimits(bitset bits, Zone* zone); |
| 909 | |
| 910 | bool SimplyEquals(Type* that); |
| 911 | |
| 912 | static int AddToUnion(Type* type, UnionType* result, int size, Zone* zone); |
| 913 | static int IntersectAux(Type* type, Type* other, UnionType* result, int size, |
| 914 | RangeType::Limits* limits, Zone* zone); |
| 915 | static Type* NormalizeUnion(Type* unioned, int size, Zone* zone); |
| 916 | static Type* NormalizeRangeAndBitset(Type* range, bitset* bits, Zone* zone); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 917 | }; |
| 918 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 919 | // ----------------------------------------------------------------------------- |
| 920 | // Type bounds. A simple struct to represent a pair of lower/upper types. |
| 921 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 922 | struct Bounds { |
| 923 | Type* lower; |
| 924 | Type* upper; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 925 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 926 | Bounds() |
| 927 | : // Make sure accessing uninitialized bounds crashes big-time. |
| 928 | lower(nullptr), |
| 929 | upper(nullptr) {} |
| 930 | explicit Bounds(Type* t) : lower(t), upper(t) {} |
| 931 | Bounds(Type* l, Type* u) : lower(l), upper(u) { DCHECK(lower->Is(upper)); } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 932 | |
| 933 | // Unrestricted bounds. |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 934 | static Bounds Unbounded() { return Bounds(Type::None(), Type::Any()); } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 935 | |
| 936 | // Meet: both b1 and b2 are known to hold. |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 937 | static Bounds Both(Bounds b1, Bounds b2, Zone* zone) { |
| 938 | Type* lower = Type::Union(b1.lower, b2.lower, zone); |
| 939 | Type* upper = Type::Intersect(b1.upper, b2.upper, zone); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 940 | // Lower bounds are considered approximate, correct as necessary. |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 941 | if (!lower->Is(upper)) lower = upper; |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 942 | return Bounds(lower, upper); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 943 | } |
| 944 | |
| 945 | // Join: either b1 or b2 is known to hold. |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 946 | static Bounds Either(Bounds b1, Bounds b2, Zone* zone) { |
| 947 | Type* lower = Type::Intersect(b1.lower, b2.lower, zone); |
| 948 | Type* upper = Type::Union(b1.upper, b2.upper, zone); |
| 949 | return Bounds(lower, upper); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 950 | } |
| 951 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 952 | static Bounds NarrowLower(Bounds b, Type* t, Zone* zone) { |
| 953 | Type* lower = Type::Union(b.lower, t, zone); |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 954 | // Lower bounds are considered approximate, correct as necessary. |
| 955 | if (!lower->Is(b.upper)) lower = b.upper; |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 956 | return Bounds(lower, b.upper); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 957 | } |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 958 | static Bounds NarrowUpper(Bounds b, Type* t, Zone* zone) { |
| 959 | Type* lower = b.lower; |
| 960 | Type* upper = Type::Intersect(b.upper, t, zone); |
Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame] | 961 | // Lower bounds are considered approximate, correct as necessary. |
| 962 | if (!lower->Is(upper)) lower = upper; |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 963 | return Bounds(lower, upper); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 964 | } |
| 965 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 966 | bool Narrows(Bounds that) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 967 | return that.lower->Is(this->lower) && this->upper->Is(that.upper); |
| 968 | } |
| 969 | }; |
| 970 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 971 | } // namespace internal |
| 972 | } // namespace v8 |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 973 | |
| 974 | #endif // V8_TYPES_H_ |