[ptr-compr] Remove CompressedSigned MachineRepresentation

Since smi-corrputing, TaggedSigned (aka known smis) only have the lower
bits used. This renders CompressedSigned useless.

Bug: v8:7703
Change-Id: Id59aaebc24d670ed32c483ceecf77fd194405ee4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1903445
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64883}

src/codegen/machine-type.cc

@@ -14,7 +14,6 @@ bool IsSubtype(MachineRepresentation rep1, MachineRepresentation rep2) {
     case MachineRepresentation::kTaggedSigned:  // Fall through.
     case MachineRepresentation::kTaggedPointer:
       return rep2 == MachineRepresentation::kTagged;
-    case MachineRepresentation::kCompressedSigned:  // Fall through.
     case MachineRepresentation::kCompressedPointer:
       return rep2 == MachineRepresentation::kCompressed;
     default:
@@ -52,8 +51,6 @@ const char* MachineReprToString(MachineRepresentation rep) {
       return "kRepTaggedPointer";
     case MachineRepresentation::kTagged:
       return "kRepTagged";
-    case MachineRepresentation::kCompressedSigned:
-      return "kRepCompressedSigned";
     case MachineRepresentation::kCompressedPointer:
       return "kRepCompressedPointer";
     case MachineRepresentation::kCompressed:

src/codegen/machine-type.h

@@ -24,7 +24,6 @@ enum class MachineRepresentation : uint8_t {
   kTaggedSigned,
   kTaggedPointer,
   kTagged,
-  kCompressedSigned,
   kCompressedPointer,
   kCompressed,
   // FP representations must be last, and in order of increasing size.
@@ -106,12 +105,8 @@ class MachineType {
   }
   constexpr bool IsCompressed() const {
     return representation() == MachineRepresentation::kCompressedPointer ||
-           representation() == MachineRepresentation::kCompressedSigned ||
            representation() == MachineRepresentation::kCompressed;
   }
-  constexpr bool IsCompressedSigned() const {
-    return representation() == MachineRepresentation::kCompressedSigned;
-  }
   constexpr bool IsCompressedPointer() const {
     return representation() == MachineRepresentation::kCompressedPointer;
   }
@@ -181,10 +176,6 @@ class MachineType {
   constexpr static MachineType AnyTagged() {
     return MachineType(MachineRepresentation::kTagged, MachineSemantic::kAny);
   }
-  constexpr static MachineType CompressedSigned() {
-    return MachineType(MachineRepresentation::kCompressedSigned,
-                       MachineSemantic::kInt32);
-  }
   constexpr static MachineType CompressedPointer() {
     return MachineType(MachineRepresentation::kCompressedPointer,
                        MachineSemantic::kAny);
@@ -271,8 +262,6 @@ class MachineType {
         return MachineType::AnyCompressed();
       case MachineRepresentation::kCompressedPointer:
         return MachineType::CompressedPointer();
-      case MachineRepresentation::kCompressedSigned:
-        return MachineType::CompressedSigned();
       default:
         UNREACHABLE();
     }
@@ -328,14 +317,8 @@ inline bool CanBeTaggedOrCompressedPointer(MachineRepresentation rep) {
   return CanBeTaggedPointer(rep) || CanBeCompressedPointer(rep);
 }
 
-inline bool CanBeCompressedSigned(MachineRepresentation rep) {
-  return rep == MachineRepresentation::kCompressed ||
-         rep == MachineRepresentation::kCompressedSigned;
-}
-
 inline bool IsAnyCompressed(MachineRepresentation rep) {
-  return CanBeCompressedPointer(rep) ||
-         rep == MachineRepresentation::kCompressedSigned;
+  return CanBeCompressedPointer(rep);
 }
 
 // Gets the log2 of the element size in bytes of the machine type.
@@ -357,7 +340,6 @@ V8_EXPORT_PRIVATE inline int ElementSizeLog2Of(MachineRepresentation rep) {
     case MachineRepresentation::kTaggedSigned:
     case MachineRepresentation::kTaggedPointer:
     case MachineRepresentation::kTagged:
-    case MachineRepresentation::kCompressedSigned:
     case MachineRepresentation::kCompressedPointer:
     case MachineRepresentation::kCompressed:
       return kTaggedSizeLog2;

src/compiler/backend/arm/instruction-selector-arm.cc

@@ -503,7 +503,6 @@ void InstructionSelector::VisitLoad(Node* node) {
     case MachineRepresentation::kSimd128:
       opcode = kArmVld1S128;
       break;
-    case MachineRepresentation::kCompressedSigned:   // Fall through.
     case MachineRepresentation::kCompressedPointer:  // Fall through.
     case MachineRepresentation::kCompressed:         // Fall through.
     case MachineRepresentation::kWord64:             // Fall through.
@@ -584,7 +583,6 @@ void InstructionSelector::VisitStore(Node* node) {
       case MachineRepresentation::kSimd128:
         opcode = kArmVst1S128;
         break;
-      case MachineRepresentation::kCompressedSigned:   // Fall through.
       case MachineRepresentation::kCompressedPointer:  // Fall through.
       case MachineRepresentation::kCompressed:         // Fall through.
       case MachineRepresentation::kWord64:             // Fall through.

src/compiler/backend/arm64/instruction-selector-arm64.cc

@@ -619,7 +619,6 @@ void InstructionSelector::VisitLoad(Node* node) {
       opcode = kArm64LdrW;
       immediate_mode = kLoadStoreImm32;
       break;
-    case MachineRepresentation::kCompressedSigned:   // Fall through.
     case MachineRepresentation::kCompressedPointer:  // Fall through.
     case MachineRepresentation::kCompressed:
 #ifdef V8_COMPRESS_POINTERS
@@ -736,7 +735,6 @@ void InstructionSelector::VisitStore(Node* node) {
         opcode = kArm64StrW;
         immediate_mode = kLoadStoreImm32;
         break;
-      case MachineRepresentation::kCompressedSigned:   // Fall through.
       case MachineRepresentation::kCompressedPointer:  // Fall through.
       case MachineRepresentation::kCompressed:
 #ifdef V8_COMPRESS_POINTERS

src/compiler/backend/ia32/instruction-selector-ia32.cc

@@ -363,7 +363,6 @@ void InstructionSelector::VisitLoad(Node* node) {
     case MachineRepresentation::kSimd128:
       opcode = kIA32Movdqu;
       break;
-    case MachineRepresentation::kCompressedSigned:   // Fall through.
     case MachineRepresentation::kCompressedPointer:  // Fall through.
     case MachineRepresentation::kCompressed:         // Fall through.
     case MachineRepresentation::kWord64:             // Fall through.
@@ -444,7 +443,6 @@ void InstructionSelector::VisitStore(Node* node) {
       case MachineRepresentation::kSimd128:
         opcode = kIA32Movdqu;
         break;
-      case MachineRepresentation::kCompressedSigned:   // Fall through.
       case MachineRepresentation::kCompressedPointer:  // Fall through.
       case MachineRepresentation::kCompressed:         // Fall through.
       case MachineRepresentation::kWord64:             // Fall through.

src/compiler/backend/instruction-selector-impl.h

@@ -346,7 +346,6 @@ class OperandGenerator {
           case MachineRepresentation::kTaggedSigned:
           case MachineRepresentation::kTaggedPointer:
           case MachineRepresentation::kCompressed:
-          case MachineRepresentation::kCompressedSigned:
           case MachineRepresentation::kCompressedPointer:
             return Constant(static_cast<int32_t>(0));
           case MachineRepresentation::kFloat64:

src/compiler/backend/instruction.cc

@@ -228,9 +228,6 @@ std::ostream& operator<<(std::ostream& os, const InstructionOperand& op) {
         case MachineRepresentation::kTagged:
           os << "|t";
           break;
-        case MachineRepresentation::kCompressedSigned:
-          os << "|cs";
-          break;
         case MachineRepresentation::kCompressedPointer:
           os << "|cp";
           break;
@@ -892,7 +889,6 @@ static MachineRepresentation FilterRepresentation(MachineRepresentation rep) {
     case MachineRepresentation::kFloat32:
     case MachineRepresentation::kFloat64:
     case MachineRepresentation::kSimd128:
-    case MachineRepresentation::kCompressedSigned:
     case MachineRepresentation::kCompressedPointer:
     case MachineRepresentation::kCompressed:
       return rep;

src/compiler/backend/instruction.h

@@ -472,7 +472,6 @@ class LocationOperand : public InstructionOperand {
       case MachineRepresentation::kTaggedSigned:
       case MachineRepresentation::kTaggedPointer:
       case MachineRepresentation::kTagged:
-      case MachineRepresentation::kCompressedSigned:
       case MachineRepresentation::kCompressedPointer:
       case MachineRepresentation::kCompressed:
         return true;

src/compiler/backend/register-allocator.cc

@@ -79,7 +79,6 @@ int GetByteWidth(MachineRepresentation rep) {
     case MachineRepresentation::kTaggedSigned:
     case MachineRepresentation::kTaggedPointer:
     case MachineRepresentation::kTagged:
-    case MachineRepresentation::kCompressedSigned:
     case MachineRepresentation::kCompressedPointer:
     case MachineRepresentation::kCompressed:
       // TODO(ishell): kTaggedSize once half size locations are supported.

src/compiler/backend/x64/instruction-selector-x64.cc

@@ -241,7 +241,6 @@ ArchOpcode GetLoadOpcode(LoadRepresentation load_rep) {
     case MachineRepresentation::kWord32:
       opcode = kX64Movl;
       break;
-    case MachineRepresentation::kCompressedSigned:   // Fall through.
     case MachineRepresentation::kCompressedPointer:  // Fall through.
     case MachineRepresentation::kCompressed:
 #ifdef V8_COMPRESS_POINTERS
@@ -290,7 +289,6 @@ ArchOpcode GetStoreOpcode(StoreRepresentation store_rep) {
       return kX64Movw;
     case MachineRepresentation::kWord32:
       return kX64Movl;
-    case MachineRepresentation::kCompressedSigned:   // Fall through.
     case MachineRepresentation::kCompressedPointer:  // Fall through.
     case MachineRepresentation::kCompressed:
 #ifdef V8_COMPRESS_POINTERS
@@ -630,7 +628,6 @@ bool TryMergeTruncateInt64ToInt32IntoLoad(InstructionSelector* selector,
       case MachineRepresentation::kWord64:
       case MachineRepresentation::kTaggedSigned:
       case MachineRepresentation::kTagged:
-      case MachineRepresentation::kCompressedSigned:  // Fall through.
       case MachineRepresentation::kCompressed:        // Fall through.
         opcode = kX64Movl;
         break;

src/compiler/js-native-context-specialization.cc

@@ -2436,7 +2436,6 @@ JSNativeContextSpecialization::BuildPropertyStore(
         break;
       case MachineRepresentation::kNone:
       case MachineRepresentation::kBit:
-      case MachineRepresentation::kCompressedSigned:
       case MachineRepresentation::kCompressedPointer:
       case MachineRepresentation::kCompressed:
       case MachineRepresentation::kWord8:

src/compiler/load-elimination.cc

@@ -1069,7 +1069,6 @@ Reduction LoadElimination::ReduceLoadElement(Node* node) {
     case MachineRepresentation::kWord32:
     case MachineRepresentation::kWord64:
     case MachineRepresentation::kFloat32:
-    case MachineRepresentation::kCompressedSigned:
     case MachineRepresentation::kCompressedPointer:
     case MachineRepresentation::kCompressed:
       // TODO(turbofan): Add support for doing the truncations.
@@ -1124,7 +1123,6 @@ Reduction LoadElimination::ReduceStoreElement(Node* node) {
     case MachineRepresentation::kWord32:
     case MachineRepresentation::kWord64:
     case MachineRepresentation::kFloat32:
-    case MachineRepresentation::kCompressedSigned:
     case MachineRepresentation::kCompressedPointer:
     case MachineRepresentation::kCompressed:
       // TODO(turbofan): Add support for doing the truncations.
@@ -1427,7 +1425,6 @@ LoadElimination::IndexRange LoadElimination::FieldIndexOf(
     case MachineRepresentation::kTaggedSigned:
     case MachineRepresentation::kTaggedPointer:
     case MachineRepresentation::kTagged:
-    case MachineRepresentation::kCompressedSigned:
     case MachineRepresentation::kCompressedPointer:
     case MachineRepresentation::kCompressed:
       break;

src/compiler/machine-graph-verifier.cc

@@ -619,7 +619,6 @@ class MachineRepresentationChecker {
                 break;
               case MachineRepresentation::kCompressed:
               case MachineRepresentation::kCompressedPointer:
-              case MachineRepresentation::kCompressedSigned:
                 for (int i = 0; i < node->op()->ValueInputCount(); ++i) {
                     CheckValueInputIsCompressedOrTagged(node, i);
                 }
@@ -722,7 +721,6 @@ class MachineRepresentationChecker {
     switch (inferrer_->GetRepresentation(input)) {
       case MachineRepresentation::kCompressed:
       case MachineRepresentation::kCompressedPointer:
-      case MachineRepresentation::kCompressedSigned:
         return;
       default:
         break;
@@ -758,7 +756,6 @@ class MachineRepresentationChecker {
     switch (inferrer_->GetRepresentation(input)) {
       case MachineRepresentation::kCompressed:
       case MachineRepresentation::kCompressedPointer:
-      case MachineRepresentation::kCompressedSigned:
       case MachineRepresentation::kTagged:
       case MachineRepresentation::kTaggedPointer:
       case MachineRepresentation::kTaggedSigned:
@@ -844,7 +841,6 @@ class MachineRepresentationChecker {
       case MachineRepresentation::kWord32:
         return;
       case MachineRepresentation::kCompressed:
-      case MachineRepresentation::kCompressedSigned:
       case MachineRepresentation::kCompressedPointer:
         return;
       default:
@@ -989,7 +985,6 @@ class MachineRepresentationChecker {
         // kTaggedPointer and the other way around, but at the moment, this
         // happens in dead code.
         return IsAnyTagged(actual);
-      case MachineRepresentation::kCompressedSigned:
       case MachineRepresentation::kCompressedPointer:
       case MachineRepresentation::kFloat32:
       case MachineRepresentation::kFloat64:

src/compiler/machine-operator.cc

@@ -500,7 +500,6 @@ MachineType AtomicOpType(Operator const* op) {
   V(TaggedSigned)            \
   V(TaggedPointer)           \
   V(AnyTagged)               \
-  V(CompressedSigned)        \
   V(CompressedPointer)       \
   V(AnyCompressed)
 
@@ -515,7 +514,6 @@ MachineType AtomicOpType(Operator const* op) {
   V(kTaggedSigned)                     \
   V(kTaggedPointer)                    \
   V(kTagged)                           \
-  V(kCompressedSigned)                 \
   V(kCompressedPointer)                \
   V(kCompressed)
 

src/compiler/representation-change.cc

@@ -216,7 +216,6 @@ Node* RepresentationChanger::GetRepresentationFor(
     case MachineRepresentation::kNone:
       return node;
     case MachineRepresentation::kCompressed:
-    case MachineRepresentation::kCompressedSigned:
     case MachineRepresentation::kCompressedPointer:
       UNREACHABLE();
   }

src/compiler/simplified-lowering.cc

@@ -144,7 +144,6 @@ UseInfo TruncatingUseInfoFromRepresentation(MachineRepresentation rep) {
       return UseInfo::Word64();
     case MachineRepresentation::kBit:
       return UseInfo::Bool();
-    case MachineRepresentation::kCompressedSigned:
     case MachineRepresentation::kCompressedPointer:
     case MachineRepresentation::kCompressed:
     case MachineRepresentation::kSimd128: