[Turbofan] Add Simd128 registers to RegisterConfiguration.

-Defines SIMD128_REGISTERS for all platforms.
-Adds Simd128 register information to RegisterConfiguration, and implements
aliasing calculations.

LOG=N
BUG=v8:4124

Review-Url: https://codereview.chromium.org/2092103004
Cr-Commit-Position: refs/heads/master@{#37437}

src/arm/assembler-arm.h

@@ -69,6 +69,10 @@ namespace internal {
   V(d16) V(d17) V(d18) V(d19) V(d20) V(d21) V(d22) V(d23) \
   V(d24) V(d25) V(d26) V(d27) V(d28) V(d29) V(d30) V(d31)
 
+#define SIMD128_REGISTERS(V)                              \
+  V(q0)  V(q1)  V(q2)  V(q3)  V(q4)  V(q5)  V(q6)  V(q7)  \
+  V(q8)  V(q9)  V(q10) V(q11) V(q12) V(q13) V(q14) V(q15)
+
 #define ALLOCATABLE_DOUBLE_REGISTERS(V)                   \
   V(d0)  V(d1)  V(d2)  V(d3)  V(d4)  V(d5)  V(d6)  V(d7)  \
   V(d8)  V(d9)  V(d10) V(d11) V(d12) V(d13)               \

src/arm64/assembler-arm64.h

@@ -40,7 +40,7 @@ namespace internal {
   R(x8)  R(x9)  R(x10) R(x11) R(x12) R(x13) R(x14) R(x15) \
   R(x18) R(x19) R(x20) R(x21) R(x22) R(x23) R(x24) R(x27)
 
-#define FLOAT_REGISTERS(V)                               \
+#define FLOAT_REGISTERS(V)                                \
   V(s0)  V(s1)  V(s2)  V(s3)  V(s4)  V(s5)  V(s6)  V(s7)  \
   V(s8)  V(s9)  V(s10) V(s11) V(s12) V(s13) V(s14) V(s15) \
   V(s16) V(s17) V(s18) V(s19) V(s20) V(s21) V(s22) V(s23) \
@@ -52,6 +52,10 @@ namespace internal {
   R(d16) R(d17) R(d18) R(d19) R(d20) R(d21) R(d22) R(d23) \
   R(d24) R(d25) R(d26) R(d27) R(d28) R(d29) R(d30) R(d31)
 
+#define SIMD128_REGISTERS(V)                              \
+  V(q0)  V(q1)  V(q2)  V(q3)  V(q4)  V(q5)  V(q6)  V(q7)  \
+  V(q8)  V(q9)  V(q10) V(q11) V(q12) V(q13) V(q14) V(q15)
+
 #define ALLOCATABLE_DOUBLE_REGISTERS(R)                   \
   R(d0)  R(d1)  R(d2)  R(d3)  R(d4)  R(d5)  R(d6)  R(d7)  \
   R(d8)  R(d9)  R(d10) R(d11) R(d12) R(d13) R(d14) R(d16) \

src/compiler/move-optimizer.cc

@@ -32,26 +32,41 @@ bool Blocks(const OperandSet& set, const InstructionOperand& operand) {
   // Only FP registers on archs with non-simple aliasing need extra checks.
   if (!operand.IsFPRegister() || kSimpleFPAliasing) return false;
 
+  // Check operand against operands of other FP types for interference.
   const LocationOperand& loc = LocationOperand::cast(operand);
   MachineRepresentation rep = loc.representation();
-  MachineRepresentation other_fp_rep = rep == MachineRepresentation::kFloat64
-                                           ? MachineRepresentation::kFloat32
-                                           : MachineRepresentation::kFloat64;
+  MachineRepresentation other_rep1, other_rep2;
+  switch (rep) {
+    case MachineRepresentation::kFloat32:
+      other_rep1 = MachineRepresentation::kFloat64;
+      other_rep2 = MachineRepresentation::kSimd128;
+      break;
+    case MachineRepresentation::kFloat64:
+      other_rep1 = MachineRepresentation::kFloat32;
+      other_rep2 = MachineRepresentation::kSimd128;
+      break;
+    case MachineRepresentation::kSimd128:
+      other_rep1 = MachineRepresentation::kFloat32;
+      other_rep2 = MachineRepresentation::kFloat64;
+      break;
+    default:
+      UNREACHABLE();
+      break;
+  }
   const RegisterConfiguration* config = RegisterConfiguration::Turbofan();
-  if (config->fp_aliasing_kind() != RegisterConfiguration::COMBINE) {
-    // Overlap aliasing case.
-    return set.find(LocationOperand(loc.kind(), loc.location_kind(),
-                                    other_fp_rep, loc.register_code())) !=
-           set.end();
-  }
-  // Combine aliasing case.
-  int alias_base_index = -1;
-  int aliases = config->GetAliases(rep, loc.register_code(), other_fp_rep,
-                                   &alias_base_index);
+  int base = -1;
+  int aliases = config->GetAliases(rep, loc.register_code(), other_rep1, &base);
+  DCHECK(aliases > 0 || (aliases == 0 && base == -1));
+  while (aliases--) {
+    if (set.find(LocationOperand(loc.kind(), loc.location_kind(), other_rep1,
+                                 base + aliases)) != set.end())
+      return true;
+  }
+  aliases = config->GetAliases(rep, loc.register_code(), other_rep2, &base);
+  DCHECK(aliases > 0 || (aliases == 0 && base == -1));
   while (aliases--) {
-    int aliased_reg = alias_base_index + aliases;
-    if (set.find(LocationOperand(loc.kind(), loc.location_kind(), other_fp_rep,
-                                 aliased_reg)) != set.end())
+    if (set.find(LocationOperand(loc.kind(), loc.location_kind(), other_rep2,
+                                 base + aliases)) != set.end())
       return true;
   }
   return false;

src/compiler/register-allocator.cc

@@ -1344,6 +1344,8 @@ RegisterAllocationData::RegisterAllocationData(
                                allocation_zone()),
       fixed_double_live_ranges_(this->config()->num_double_registers(), nullptr,
                                 allocation_zone()),
+      fixed_simd128_live_ranges_(this->config()->num_simd128_registers(),
+                                 nullptr, allocation_zone()),
       spill_ranges_(code->VirtualRegisterCount(), nullptr, allocation_zone()),
       delayed_references_(allocation_zone()),
       assigned_registers_(nullptr),
@@ -1521,12 +1523,14 @@ void RegisterAllocationData::MarkAllocated(MachineRepresentation rep,
                                            int index) {
   switch (rep) {
     case MachineRepresentation::kFloat32:
+    case MachineRepresentation::kSimd128:
       if (kSimpleFPAliasing) {
         assigned_double_registers_->Add(index);
       } else {
         int alias_base_index = -1;
         int aliases = config()->GetAliases(
             rep, index, MachineRepresentation::kFloat64, &alias_base_index);
+        DCHECK(aliases > 0 || (aliases == 0 && alias_base_index == -1));
         while (aliases--) {
           int aliased_reg = alias_base_index + aliases;
           assigned_double_registers_->Add(aliased_reg);
@@ -1857,17 +1861,22 @@ void LiveRangeBuilder::AddInitialIntervals(const InstructionBlock* block,
 }
 
 int LiveRangeBuilder::FixedFPLiveRangeID(int index, MachineRepresentation rep) {
+  int result = -index - 1;
   switch (rep) {
+    case MachineRepresentation::kSimd128:
+      result -= config()->num_float_registers();
+    // Fall through.
     case MachineRepresentation::kFloat32:
-      return -index - 1 - config()->num_general_registers();
+      result -= config()->num_double_registers();
+    // Fall through.
     case MachineRepresentation::kFloat64:
-      return -index - 1 - config()->num_general_registers() -
-             config()->num_float_registers();
+      result -= config()->num_general_registers();
+      break;
     default:
+      UNREACHABLE();
       break;
   }
-  UNREACHABLE();
-  return 0;
+  return result;
 }
 
 TopLevelLiveRange* LiveRangeBuilder::FixedLiveRangeFor(int index) {
@@ -1887,27 +1896,44 @@ TopLevelLiveRange* LiveRangeBuilder::FixedLiveRangeFor(int index) {
 TopLevelLiveRange* LiveRangeBuilder::FixedFPLiveRangeFor(
     int index, MachineRepresentation rep) {
   TopLevelLiveRange* result = nullptr;
-  if (rep == MachineRepresentation::kFloat64) {
-    DCHECK(index < config()->num_double_registers());
-    result = data()->fixed_double_live_ranges()[index];
-    if (result == nullptr) {
-      result = data()->NewLiveRange(FixedFPLiveRangeID(index, rep), rep);
-      DCHECK(result->IsFixed());
-      result->set_assigned_register(index);
-      data()->MarkAllocated(rep, index);
-      data()->fixed_double_live_ranges()[index] = result;
-    }
-  } else {
-    DCHECK(rep == MachineRepresentation::kFloat32);
-    DCHECK(index < config()->num_float_registers());
-    result = data()->fixed_float_live_ranges()[index];
-    if (result == nullptr) {
-      result = data()->NewLiveRange(FixedFPLiveRangeID(index, rep), rep);
-      DCHECK(result->IsFixed());
-      result->set_assigned_register(index);
-      data()->MarkAllocated(rep, index);
-      data()->fixed_float_live_ranges()[index] = result;
-    }
+  switch (rep) {
+    case MachineRepresentation::kFloat32:
+      DCHECK(rep == MachineRepresentation::kFloat32);
+      DCHECK(index < config()->num_float_registers());
+      result = data()->fixed_float_live_ranges()[index];
+      if (result == nullptr) {
+        result = data()->NewLiveRange(FixedFPLiveRangeID(index, rep), rep);
+        DCHECK(result->IsFixed());
+        result->set_assigned_register(index);
+        data()->MarkAllocated(rep, index);
+        data()->fixed_float_live_ranges()[index] = result;
+      }
+      break;
+    case MachineRepresentation::kFloat64:
+      DCHECK(index < config()->num_double_registers());
+      result = data()->fixed_double_live_ranges()[index];
+      if (result == nullptr) {
+        result = data()->NewLiveRange(FixedFPLiveRangeID(index, rep), rep);
+        DCHECK(result->IsFixed());
+        result->set_assigned_register(index);
+        data()->MarkAllocated(rep, index);
+        data()->fixed_double_live_ranges()[index] = result;
+      }
+      break;
+    case MachineRepresentation::kSimd128:
+      DCHECK(index < config()->num_simd128_registers());
+      result = data()->fixed_simd128_live_ranges()[index];
+      if (result == nullptr) {
+        result = data()->NewLiveRange(FixedFPLiveRangeID(index, rep), rep);
+        DCHECK(result->IsFixed());
+        result->set_assigned_register(index);
+        data()->MarkAllocated(rep, index);
+        data()->fixed_simd128_live_ranges()[index] = result;
+      }
+      break;
+    default:
+      UNREACHABLE();
+      break;
   }
   return result;
 }
@@ -2051,6 +2077,14 @@ void LiveRangeBuilder::ProcessInstructions(const InstructionBlock* block,
           range->AddUseInterval(curr_position, curr_position.End(),
                                 allocation_zone());
         }
+        for (int i = 0; i < config()->num_allocatable_simd128_registers();
+             ++i) {
+          int code = config()->GetAllocatableSimd128Code(i);
+          TopLevelLiveRange* range =
+              FixedFPLiveRangeFor(code, MachineRepresentation::kSimd128);
+          range->AddUseInterval(curr_position, curr_position.End(),
+                                allocation_zone());
+        }
       }
     }
 
@@ -2787,15 +2821,22 @@ void LinearScanAllocator::InactiveToActive(LiveRange* range) {
 
 
 bool LinearScanAllocator::TryAllocateFreeReg(LiveRange* current) {
+  MachineRepresentation rep = current->representation();
   int num_regs = num_registers();
   int num_codes = num_allocatable_registers();
   const int* codes = allocatable_register_codes();
-  if (!kSimpleFPAliasing &&
-      (current->representation() == MachineRepresentation::kFloat32)) {
-    num_regs = data()->config()->num_float_registers();
-    num_codes = data()->config()->num_allocatable_float_registers();
-    codes = data()->config()->allocatable_float_codes();
+  if (!kSimpleFPAliasing) {
+    if (rep == MachineRepresentation::kFloat32) {
+      num_regs = data()->config()->num_float_registers();
+      num_codes = data()->config()->num_allocatable_float_registers();
+      codes = data()->config()->allocatable_float_codes();
+    } else if (rep == MachineRepresentation::kSimd128) {
+      num_regs = data()->config()->num_simd128_registers();
+      num_codes = data()->config()->num_allocatable_simd128_registers();
+      codes = data()->config()->allocatable_simd128_codes();
+    }
   }
+
   LifetimePosition free_until_pos[RegisterConfiguration::kMaxFPRegisters];
   for (int i = 0; i < num_regs; i++) {
     free_until_pos[i] = LifetimePosition::MaxPosition();
@@ -2810,8 +2851,8 @@ bool LinearScanAllocator::TryAllocateFreeReg(LiveRange* current) {
     } else {
       int alias_base_index = -1;
       int aliases = data()->config()->GetAliases(
-          cur_active->representation(), cur_reg, current->representation(),
-          &alias_base_index);
+          cur_active->representation(), cur_reg, rep, &alias_base_index);
+      DCHECK(aliases > 0 || (aliases == 0 && alias_base_index == -1));
       while (aliases--) {
         int aliased_reg = alias_base_index + aliases;
         free_until_pos[aliased_reg] =
@@ -2833,8 +2874,8 @@ bool LinearScanAllocator::TryAllocateFreeReg(LiveRange* current) {
     } else {
       int alias_base_index = -1;
       int aliases = data()->config()->GetAliases(
-          cur_inactive->representation(), cur_reg, current->representation(),
-          &alias_base_index);
+          cur_inactive->representation(), cur_reg, rep, &alias_base_index);
+      DCHECK(aliases > 0 || (aliases == 0 && alias_base_index == -1));
       while (aliases--) {
         int aliased_reg = alias_base_index + aliases;
         free_until_pos[aliased_reg] =
@@ -2904,14 +2945,20 @@ void LinearScanAllocator::AllocateBlockedReg(LiveRange* current) {
     return;
   }
 
+  MachineRepresentation rep = current->representation();
   int num_regs = num_registers();
   int num_codes = num_allocatable_registers();
   const int* codes = allocatable_register_codes();
-  if (!kSimpleFPAliasing &&
-      (current->representation() == MachineRepresentation::kFloat32)) {
-    num_regs = data()->config()->num_float_registers();
-    num_codes = data()->config()->num_allocatable_float_registers();
-    codes = data()->config()->allocatable_float_codes();
+  if (!kSimpleFPAliasing) {
+    if (rep == MachineRepresentation::kFloat32) {
+      num_regs = data()->config()->num_float_registers();
+      num_codes = data()->config()->num_allocatable_float_registers();
+      codes = data()->config()->allocatable_float_codes();
+    } else if (rep == MachineRepresentation::kSimd128) {
+      num_regs = data()->config()->num_simd128_registers();
+      num_codes = data()->config()->num_allocatable_simd128_registers();
+      codes = data()->config()->allocatable_simd128_codes();
+    }
   }
 
   LifetimePosition use_pos[RegisterConfiguration::kMaxFPRegisters];
@@ -2940,8 +2987,8 @@ void LinearScanAllocator::AllocateBlockedReg(LiveRange* current) {
     } else {
       int alias_base_index = -1;
       int aliases = data()->config()->GetAliases(
-          range->representation(), cur_reg, current->representation(),
-          &alias_base_index);
+          range->representation(), cur_reg, rep, &alias_base_index);
+      DCHECK(aliases > 0 || (aliases == 0 && alias_base_index == -1));
       while (aliases--) {
         int aliased_reg = alias_base_index + aliases;
         if (is_fixed_or_cant_spill) {
@@ -2976,8 +3023,8 @@ void LinearScanAllocator::AllocateBlockedReg(LiveRange* current) {
     } else {
       int alias_base_index = -1;
       int aliases = data()->config()->GetAliases(
-          range->representation(), cur_reg, current->representation(),
-          &alias_base_index);
+          range->representation(), cur_reg, rep, &alias_base_index);
+      DCHECK(aliases > 0 || (aliases == 0 && alias_base_index == -1));
       while (aliases--) {
         int aliased_reg = alias_base_index + aliases;
         if (is_fixed) {

src/compiler/register-allocator.h

@@ -779,6 +779,12 @@ class RegisterAllocationData final : public ZoneObject {
   const ZoneVector<TopLevelLiveRange*>& fixed_double_live_ranges() const {
     return fixed_double_live_ranges_;
   }
+  ZoneVector<TopLevelLiveRange*>& fixed_simd128_live_ranges() {
+    return fixed_simd128_live_ranges_;
+  }
+  const ZoneVector<TopLevelLiveRange*>& fixed_simd128_live_ranges() const {
+    return fixed_simd128_live_ranges_;
+  }
   ZoneVector<BitVector*>& live_in_sets() { return live_in_sets_; }
   ZoneVector<BitVector*>& live_out_sets() { return live_out_sets_; }
   ZoneVector<SpillRange*>& spill_ranges() { return spill_ranges_; }
@@ -842,6 +848,7 @@ class RegisterAllocationData final : public ZoneObject {
   ZoneVector<TopLevelLiveRange*> fixed_live_ranges_;
   ZoneVector<TopLevelLiveRange*> fixed_float_live_ranges_;
   ZoneVector<TopLevelLiveRange*> fixed_double_live_ranges_;
+  ZoneVector<TopLevelLiveRange*> fixed_simd128_live_ranges_;
   ZoneVector<SpillRange*> spill_ranges_;
   DelayedReferences delayed_references_;
   BitVector* assigned_registers_;

src/ia32/assembler-ia32.h

@@ -75,7 +75,7 @@ namespace internal {
   V(xmm7)
 
 #define FLOAT_REGISTERS DOUBLE_REGISTERS
-#define SIMD_REGISTERS DOUBLE_REGISTERS
+#define SIMD128_REGISTERS DOUBLE_REGISTERS
 
 #define ALLOCATABLE_DOUBLE_REGISTERS(V) \
   V(xmm1)                               \

src/machine-type.h

@@ -23,8 +23,8 @@ enum class MachineRepresentation : uint8_t {
   kWord32,
   kWord64,
   kFloat32,
-  kFloat64,
-  kSimd128,
+  kFloat64,  // must follow kFloat32
+  kSimd128,  // must follow kFloat64
   kTagged
 };
 

src/mips/assembler-mips.h

@@ -64,6 +64,7 @@ namespace internal {
   V(f24) V(f25) V(f26) V(f27) V(f28) V(f29) V(f30) V(f31)
 
 #define FLOAT_REGISTERS DOUBLE_REGISTERS
+#define SIMD128_REGISTERS DOUBLE_REGISTERS
 
 #define ALLOCATABLE_DOUBLE_REGISTERS(V)                   \
   V(f0)  V(f2)  V(f4)  V(f6)  V(f8)  V(f10) V(f12) V(f14) \

src/mips64/assembler-mips64.h

@@ -64,6 +64,7 @@ namespace internal {
   V(f24) V(f25) V(f26) V(f27) V(f28) V(f29) V(f30) V(f31)
 
 #define FLOAT_REGISTERS DOUBLE_REGISTERS
+#define SIMD128_REGISTERS DOUBLE_REGISTERS
 
 #define ALLOCATABLE_DOUBLE_REGISTERS(V)                   \
   V(f0)  V(f2)  V(f4)  V(f6)  V(f8)  V(f10) V(f12) V(f14) \

src/ppc/assembler-ppc.h

@@ -110,6 +110,7 @@ namespace internal {
   V(d24) V(d25) V(d26) V(d27) V(d28) V(d29) V(d30) V(d31)
 
 #define FLOAT_REGISTERS DOUBLE_REGISTERS
+#define SIMD128_REGISTERS DOUBLE_REGISTERS
 
 #define ALLOCATABLE_DOUBLE_REGISTERS(V)                   \
   V(d1)  V(d2)  V(d3)  V(d4)  V(d5)  V(d6)  V(d7)         \

src/register-configuration.cc

@@ -45,10 +45,20 @@ static const char* const kDoubleRegisterNames[] = {
 #undef REGISTER_NAME
 };
 
+static const char* const kSimd128RegisterNames[] = {
+#define REGISTER_NAME(R) #R,
+    SIMD128_REGISTERS(REGISTER_NAME)
+#undef REGISTER_NAME
+};
+
 STATIC_ASSERT(RegisterConfiguration::kMaxGeneralRegisters >=
               Register::kNumRegisters);
+STATIC_ASSERT(RegisterConfiguration::kMaxFPRegisters >=
+              FloatRegister::kMaxNumRegisters);
 STATIC_ASSERT(RegisterConfiguration::kMaxFPRegisters >=
               DoubleRegister::kMaxNumRegisters);
+STATIC_ASSERT(RegisterConfiguration::kMaxFPRegisters >=
+              Simd128Register::kMaxNumRegisters);
 
 enum CompilerSelector { CRANKSHAFT, TURBOFAN };
 
@@ -93,7 +103,8 @@ class ArchDefaultRegisterConfiguration : public RegisterConfiguration {
 #endif
             kAllocatableGeneralCodes, kAllocatableDoubleCodes,
             kSimpleFPAliasing ? AliasingKind::OVERLAP : AliasingKind::COMBINE,
-            kGeneralRegisterNames, kFloatRegisterNames, kDoubleRegisterNames) {
+            kGeneralRegisterNames, kFloatRegisterNames, kDoubleRegisterNames,
+            kSimd128RegisterNames) {
   }
 };
 
@@ -128,22 +139,27 @@ RegisterConfiguration::RegisterConfiguration(
     const int* allocatable_general_codes, const int* allocatable_double_codes,
     AliasingKind fp_aliasing_kind, const char* const* general_register_names,
     const char* const* float_register_names,
-    const char* const* double_register_names)
+    const char* const* double_register_names,
+    const char* const* simd128_register_names)
     : num_general_registers_(num_general_registers),
       num_float_registers_(0),
       num_double_registers_(num_double_registers),
+      num_simd128_registers_(0),
       num_allocatable_general_registers_(num_allocatable_general_registers),
-      num_allocatable_double_registers_(num_allocatable_double_registers),
       num_allocatable_float_registers_(0),
+      num_allocatable_double_registers_(num_allocatable_double_registers),
+      num_allocatable_simd128_registers_(0),
       allocatable_general_codes_mask_(0),
-      allocatable_double_codes_mask_(0),
       allocatable_float_codes_mask_(0),
+      allocatable_double_codes_mask_(0),
+      allocatable_simd128_codes_mask_(0),
       allocatable_general_codes_(allocatable_general_codes),
       allocatable_double_codes_(allocatable_double_codes),
       fp_aliasing_kind_(fp_aliasing_kind),
       general_register_names_(general_register_names),
       float_register_names_(float_register_names),
-      double_register_names_(double_register_names) {
+      double_register_names_(double_register_names),
+      simd128_register_names_(simd128_register_names) {
   DCHECK(num_general_registers_ <= RegisterConfiguration::kMaxGeneralRegisters);
   DCHECK(num_double_registers_ <= RegisterConfiguration::kMaxFPRegisters);
   for (int i = 0; i < num_allocatable_general_registers_; ++i) {
@@ -166,67 +182,82 @@ RegisterConfiguration::RegisterConfiguration(
           base_code + 1;
       allocatable_float_codes_mask_ |= (0x3 << base_code);
     }
+    num_simd128_registers_ = num_double_registers_ / 2;
+    num_allocatable_simd128_registers_ = 0;
+    int last_simd128_code = allocatable_double_codes_[0] / 2;
+    for (int i = 1; i < num_allocatable_double_registers_; i++) {
+      int next_simd128_code = allocatable_double_codes_[i] / 2;
+      // This scheme assumes allocatable_double_codes_ are strictly increasing.
+      DCHECK_GE(next_simd128_code, last_simd128_code);
+      if (last_simd128_code == next_simd128_code) {
+        allocatable_simd128_codes_[num_allocatable_simd128_registers_++] =
+            next_simd128_code;
+        allocatable_simd128_codes_mask_ |= (0x1 << next_simd128_code);
+      }
+      last_simd128_code = next_simd128_code;
+    }
   } else {
     DCHECK(fp_aliasing_kind_ == OVERLAP);
-    num_float_registers_ = num_double_registers_;
-    num_allocatable_float_registers_ = num_allocatable_double_registers_;
+    num_float_registers_ = num_simd128_registers_ = num_double_registers_;
+    num_allocatable_float_registers_ = num_allocatable_simd128_registers_ =
+        num_allocatable_double_registers_;
     for (int i = 0; i < num_allocatable_float_registers_; ++i) {
-      allocatable_float_codes_[i] = allocatable_double_codes_[i];
+      allocatable_float_codes_[i] = allocatable_simd128_codes_[i] =
+          allocatable_double_codes_[i];
     }
-    allocatable_float_codes_mask_ = allocatable_double_codes_mask_;
+    allocatable_float_codes_mask_ = allocatable_simd128_codes_mask_ =
+        allocatable_double_codes_mask_;
   }
 }
 
+// Assert that kFloat32, kFloat64, and kSimd128 are consecutive values.
+STATIC_ASSERT(static_cast<int>(MachineRepresentation::kSimd128) ==
+              static_cast<int>(MachineRepresentation::kFloat64) + 1);
+STATIC_ASSERT(static_cast<int>(MachineRepresentation::kFloat64) ==
+              static_cast<int>(MachineRepresentation::kFloat32) + 1);
+
 int RegisterConfiguration::GetAliases(MachineRepresentation rep, int index,
                                       MachineRepresentation other_rep,
                                       int* alias_base_index) const {
   DCHECK(fp_aliasing_kind_ == COMBINE);
-  DCHECK(rep == MachineRepresentation::kFloat32 ||
-         rep == MachineRepresentation::kFloat64);
-  DCHECK(other_rep == MachineRepresentation::kFloat32 ||
-         other_rep == MachineRepresentation::kFloat64);
+  DCHECK(IsFloatingPoint(rep) && IsFloatingPoint(other_rep));
   if (rep == other_rep) {
     *alias_base_index = index;
     return 1;
   }
-  if (rep == MachineRepresentation::kFloat32) {
-    DCHECK(other_rep == MachineRepresentation::kFloat64);
-    DCHECK(index < num_allocatable_float_registers_);
-    *alias_base_index = index / 2;
-    return 1;
-  }
-  DCHECK(rep == MachineRepresentation::kFloat64);
-  DCHECK(other_rep == MachineRepresentation::kFloat32);
-  if (index * 2 >= kMaxFPRegisters) {
-    // Alias indices are out of float register range.
-    return 0;
+  int rep_int = static_cast<int>(rep);
+  int other_rep_int = static_cast<int>(other_rep);
+  if (rep_int > other_rep_int) {
+    int shift = rep_int - other_rep_int;
+    int base_index = index << shift;
+    if (base_index >= kMaxFPRegisters) {
+      // Alias indices would be out of FP register range.
+      return 0;
+    }
+    *alias_base_index = base_index;
+    return 1 << shift;
   }
-  *alias_base_index = index * 2;
-  return 2;
+  int shift = other_rep_int - rep_int;
+  *alias_base_index = index >> shift;
+  return 1;
 }
 
 bool RegisterConfiguration::AreAliases(MachineRepresentation rep, int index,
                                        MachineRepresentation other_rep,
                                        int other_index) const {
   DCHECK(fp_aliasing_kind_ == COMBINE);
-  DCHECK(rep == MachineRepresentation::kFloat32 ||
-         rep == MachineRepresentation::kFloat64);
-  DCHECK(other_rep == MachineRepresentation::kFloat32 ||
-         other_rep == MachineRepresentation::kFloat64);
+  DCHECK(IsFloatingPoint(rep) && IsFloatingPoint(other_rep));
   if (rep == other_rep) {
     return index == other_index;
   }
-  if (rep == MachineRepresentation::kFloat32) {
-    DCHECK(other_rep == MachineRepresentation::kFloat64);
-    return index / 2 == other_index;
-  }
-  DCHECK(rep == MachineRepresentation::kFloat64);
-  DCHECK(other_rep == MachineRepresentation::kFloat32);
-  if (index * 2 >= kMaxFPRegisters) {
-    // Alias indices are out of float register range.
-    return false;
+  int rep_int = static_cast<int>(rep);
+  int other_rep_int = static_cast<int>(other_rep);
+  if (rep_int > other_rep_int) {
+    int shift = rep_int - other_rep_int;
+    return index == other_index >> shift;
   }
-  return index == other_index / 2;
+  int shift = other_rep_int - rep_int;
+  return index >> shift == other_index;
 }
 
 #undef REGISTER_COUNT

src/register-configuration.h

@@ -40,19 +40,24 @@ class RegisterConfiguration {
                         AliasingKind fp_aliasing_kind,
                         char const* const* general_names,
                         char const* const* float_names,
-                        char const* const* double_names);
+                        char const* const* double_names,
+                        char const* const* simd128_names);
 
   int num_general_registers() const { return num_general_registers_; }
   int num_float_registers() const { return num_float_registers_; }
   int num_double_registers() const { return num_double_registers_; }
+  int num_simd128_registers() const { return num_simd128_registers_; }
   int num_allocatable_general_registers() const {
     return num_allocatable_general_registers_;
   }
+  int num_allocatable_float_registers() const {
+    return num_allocatable_float_registers_;
+  }
   int num_allocatable_double_registers() const {
     return num_allocatable_double_registers_;
   }
-  int num_allocatable_float_registers() const {
-    return num_allocatable_float_registers_;
+  int num_allocatable_simd128_registers() const {
+    return num_allocatable_simd128_registers_;
   }
   AliasingKind fp_aliasing_kind() const { return fp_aliasing_kind_; }
   int32_t allocatable_general_codes_mask() const {
@@ -67,17 +72,23 @@ class RegisterConfiguration {
   bool IsAllocatableGeneralCode(int index) const {
     return ((1 << index) & allocatable_general_codes_mask_) != 0;
   }
+  int GetAllocatableFloatCode(int index) const {
+    return allocatable_float_codes_[index];
+  }
+  bool IsAllocatableFloatCode(int index) const {
+    return ((1 << index) & allocatable_float_codes_mask_) != 0;
+  }
   int GetAllocatableDoubleCode(int index) const {
     return allocatable_double_codes_[index];
   }
   bool IsAllocatableDoubleCode(int index) const {
     return ((1 << index) & allocatable_double_codes_mask_) != 0;
   }
-  int GetAllocatableFloatCode(int index) const {
-    return allocatable_float_codes_[index];
+  int GetAllocatableSimd128Code(int index) const {
+    return allocatable_simd128_codes_[index];
   }
-  bool IsAllocatableFloatCode(int index) const {
-    return ((1 << index) & allocatable_float_codes_mask_) != 0;
+  bool IsAllocatableSimd128Code(int index) const {
+    return ((1 << index) & allocatable_simd128_codes_mask_) != 0;
   }
   const char* GetGeneralRegisterName(int code) const {
     return general_register_names_[code];
@@ -88,25 +99,31 @@ class RegisterConfiguration {
   const char* GetDoubleRegisterName(int code) const {
     return double_register_names_[code];
   }
+  const char* GetSimd128RegisterName(int code) const {
+    return simd128_register_names_[code];
+  }
   const int* allocatable_general_codes() const {
     return allocatable_general_codes_;
   }
+  const int* allocatable_float_codes() const {
+    return allocatable_float_codes_;
+  }
   const int* allocatable_double_codes() const {
     return allocatable_double_codes_;
   }
-  const int* allocatable_float_codes() const {
-    return allocatable_float_codes_;
+  const int* allocatable_simd128_codes() const {
+    return allocatable_simd128_codes_;
   }
 
   // Aliasing calculations for floating point registers, when fp_aliasing_kind()
-  // is COMBINE. Currently only implemented for kFloat32, or kFloat64 reps.
-  // Returns the number of aliases, and if > 0, alias_base_index is set to the
-  // index of the first alias.
+  // is COMBINE. Currently only implemented for kFloat32, kFloat64, or kSimd128
+  // reps. Returns the number of aliases, and if > 0, alias_base_index is set to
+  // the index of the first alias.
   int GetAliases(MachineRepresentation rep, int index,
                  MachineRepresentation other_rep, int* alias_base_index) const;
   // Returns a value indicating whether two registers alias each other, when
-  // fp_aliasing_kind() is COMBINE. Currently only implemented for kFloat32, or
-  // kFloat64 reps.
+  // fp_aliasing_kind() is COMBINE. Currently implemented for kFloat32,
+  // kFloat64, or kSimd128 reps.
   bool AreAliases(MachineRepresentation rep, int index,
                   MachineRepresentation other_rep, int other_index) const;
 
@@ -114,19 +131,24 @@ class RegisterConfiguration {
   const int num_general_registers_;
   int num_float_registers_;
   const int num_double_registers_;
+  int num_simd128_registers_;
   int num_allocatable_general_registers_;
-  int num_allocatable_double_registers_;
   int num_allocatable_float_registers_;
+  int num_allocatable_double_registers_;
+  int num_allocatable_simd128_registers_;
   int32_t allocatable_general_codes_mask_;
-  int32_t allocatable_double_codes_mask_;
   int32_t allocatable_float_codes_mask_;
+  int32_t allocatable_double_codes_mask_;
+  int32_t allocatable_simd128_codes_mask_;
   const int* allocatable_general_codes_;
-  const int* allocatable_double_codes_;
   int allocatable_float_codes_[kMaxFPRegisters];
+  const int* allocatable_double_codes_;
+  int allocatable_simd128_codes_[kMaxFPRegisters];
   AliasingKind fp_aliasing_kind_;
   char const* const* general_register_names_;
   char const* const* float_register_names_;
   char const* const* double_register_names_;
+  char const* const* simd128_register_names_;
 };
 
 }  // namespace internal

src/s390/assembler-s390.h

@@ -91,6 +91,7 @@ namespace internal {
   V(d8)  V(d9)  V(d10) V(d11) V(d12) V(d13) V(d14) V(d15)
 
 #define FLOAT_REGISTERS DOUBLE_REGISTERS
+#define SIMD128_REGISTERS DOUBLE_REGISTERS
 
 #define ALLOCATABLE_DOUBLE_REGISTERS(V)                   \
   V(d1)  V(d2)  V(d3)  V(d4)  V(d5)  V(d6)  V(d7)         \

src/x64/assembler-x64.h

@@ -182,6 +182,7 @@ const Register arg_reg_4 = {Register::kCode_rcx};
   V(xmm15)
 
 #define FLOAT_REGISTERS DOUBLE_REGISTERS
+#define SIMD128_REGISTERS DOUBLE_REGISTERS
 
 #define ALLOCATABLE_DOUBLE_REGISTERS(V) \
   V(xmm0)                               \

src/x87/assembler-x87.h

@@ -75,6 +75,7 @@ namespace internal {
   V(stX_7)
 
 #define FLOAT_REGISTERS DOUBLE_REGISTERS
+#define SIMD128_REGISTERS DOUBLE_REGISTERS
 
 #define ALLOCATABLE_DOUBLE_REGISTERS(V) \
   V(stX_0)                              \

test/BUILD.gn

@@ -22,8 +22,8 @@ group("gn_all") {
 
   if (v8_test_isolation_mode != "noop") {
     deps += [
-      ":bot_default_run",
       ":benchmarks_run",
+      ":bot_default_run",
       ":default_run",
       ":mozilla_run",
       ":simdjs_run",
@@ -54,7 +54,7 @@ group("default_tests") {
 
 v8_isolate_run("bot_default") {
   deps = [
-    ":default_tests", 
+    ":default_tests",
     ":webkit_run",
   ]
 
@@ -131,8 +131,8 @@ v8_isolate_run("fuzzer") {
     "..:v8_simple_json_fuzzer",
     "..:v8_simple_parser_fuzzer",
     "..:v8_simple_regexp_fuzzer",
-    "..:v8_simple_wasm_fuzzer",
     "..:v8_simple_wasm_asmjs_fuzzer",
+    "..:v8_simple_wasm_fuzzer",
   ]
 
   isolate = "fuzzer/fuzzer.isolate"

test/unittests/compiler/instruction-sequence-unittest.cc

@@ -72,7 +72,8 @@ RegisterConfiguration* InstructionSequenceTest::config() {
                           : RegisterConfiguration::COMBINE,
         general_register_names_,
         double_register_names_,  // float register names
-        double_register_names_));
+        double_register_names_,
+        double_register_names_));  // SIMD 128 register names
   }
   return config_.get();
 }

test/unittests/register-configuration-unittest.cc

@@ -10,6 +10,7 @@ namespace internal {
 
 const MachineRepresentation kFloat32 = MachineRepresentation::kFloat32;
 const MachineRepresentation kFloat64 = MachineRepresentation::kFloat64;
+const MachineRepresentation kSimd128 = MachineRepresentation::kSimd128;
 
 class RegisterConfigurationUnitTest : public ::testing::Test {
  public:
@@ -30,7 +31,7 @@ TEST_F(RegisterConfigurationUnitTest, BasicProperties) {
   RegisterConfiguration test(
       kNumGeneralRegs, kNumDoubleRegs, kNumAllocatableGeneralRegs,
       kNumAllocatableDoubleRegs, general_codes, double_codes,
-      RegisterConfiguration::OVERLAP, nullptr, nullptr, nullptr);
+      RegisterConfiguration::OVERLAP, nullptr, nullptr, nullptr, nullptr);
 
   EXPECT_EQ(test.num_general_registers(), kNumGeneralRegs);
   EXPECT_EQ(test.num_double_registers(), kNumDoubleRegs);
@@ -38,6 +39,8 @@ TEST_F(RegisterConfigurationUnitTest, BasicProperties) {
             kNumAllocatableGeneralRegs);
   EXPECT_EQ(test.num_allocatable_double_registers(), kNumAllocatableDoubleRegs);
   EXPECT_EQ(test.num_allocatable_float_registers(), kNumAllocatableDoubleRegs);
+  EXPECT_EQ(test.num_allocatable_simd128_registers(),
+            kNumAllocatableDoubleRegs);
 
   EXPECT_EQ(test.allocatable_general_codes_mask(),
             (1 << general_codes[0]) | (1 << general_codes[1]));
@@ -45,11 +48,15 @@ TEST_F(RegisterConfigurationUnitTest, BasicProperties) {
   EXPECT_EQ(test.GetAllocatableGeneralCode(1), general_codes[1]);
   EXPECT_EQ(test.allocatable_double_codes_mask(),
             (1 << double_codes[0]) | (1 << double_codes[1]));
+  EXPECT_EQ(test.GetAllocatableFloatCode(0), double_codes[0]);
   EXPECT_EQ(test.GetAllocatableDoubleCode(0), double_codes[0]);
+  EXPECT_EQ(test.GetAllocatableSimd128Code(0), double_codes[0]);
+  EXPECT_EQ(test.GetAllocatableFloatCode(1), double_codes[1]);
   EXPECT_EQ(test.GetAllocatableDoubleCode(1), double_codes[1]);
+  EXPECT_EQ(test.GetAllocatableSimd128Code(1), double_codes[1]);
 }
 
-TEST_F(RegisterConfigurationUnitTest, Aliasing) {
+TEST_F(RegisterConfigurationUnitTest, CombineAliasing) {
   const int kNumGeneralRegs = 3;
   const int kNumDoubleRegs = 4;
   const int kNumAllocatableGeneralRegs = 2;
@@ -60,7 +67,7 @@ TEST_F(RegisterConfigurationUnitTest, Aliasing) {
   RegisterConfiguration test(
       kNumGeneralRegs, kNumDoubleRegs, kNumAllocatableGeneralRegs,
       kNumAllocatableDoubleRegs, general_codes, double_codes,
-      RegisterConfiguration::COMBINE, nullptr, nullptr, nullptr);
+      RegisterConfiguration::COMBINE, nullptr, nullptr, nullptr, nullptr);
 
   // There are 3 allocatable double regs, but only 2 can alias float regs.
   EXPECT_EQ(test.num_allocatable_float_registers(), 4);
@@ -71,20 +78,41 @@ TEST_F(RegisterConfigurationUnitTest, Aliasing) {
   EXPECT_EQ(test.GetAllocatableFloatCode(2), double_codes[1] * 2);
   EXPECT_EQ(test.GetAllocatableFloatCode(3), double_codes[1] * 2 + 1);
 
+  // There are 3 allocatable double regs, but only 2 pair to form 1 SIMD reg.
+  EXPECT_EQ(test.num_allocatable_simd128_registers(), 1);
+
+  // Test that even-odd pairs of double regs combine to form a SIMD reg.
+  EXPECT_EQ(test.GetAllocatableSimd128Code(0), double_codes[0] / 2);
+
   // Registers alias themselves.
   EXPECT_TRUE(test.AreAliases(kFloat32, 0, kFloat32, 0));
   EXPECT_TRUE(test.AreAliases(kFloat64, 0, kFloat64, 0));
+  EXPECT_TRUE(test.AreAliases(kSimd128, 0, kSimd128, 0));
   // Registers don't alias other registers of the same size.
   EXPECT_FALSE(test.AreAliases(kFloat32, 1, kFloat32, 0));
   EXPECT_FALSE(test.AreAliases(kFloat64, 1, kFloat64, 0));
-  // Float registers combine in pairs and alias double registers.
+  EXPECT_FALSE(test.AreAliases(kSimd128, 1, kSimd128, 0));
+  // Float registers combine in pairs to alias a double with index / 2, and
+  // in 4's to alias a simd128 with index / 4.
   EXPECT_TRUE(test.AreAliases(kFloat32, 0, kFloat64, 0));
   EXPECT_TRUE(test.AreAliases(kFloat32, 1, kFloat64, 0));
+  EXPECT_TRUE(test.AreAliases(kFloat32, 0, kSimd128, 0));
+  EXPECT_TRUE(test.AreAliases(kFloat32, 1, kSimd128, 0));
+  EXPECT_TRUE(test.AreAliases(kFloat32, 2, kSimd128, 0));
+  EXPECT_TRUE(test.AreAliases(kFloat32, 3, kSimd128, 0));
   EXPECT_TRUE(test.AreAliases(kFloat64, 0, kFloat32, 0));
   EXPECT_TRUE(test.AreAliases(kFloat64, 0, kFloat32, 1));
+  EXPECT_TRUE(test.AreAliases(kSimd128, 0, kFloat32, 0));
+  EXPECT_TRUE(test.AreAliases(kSimd128, 0, kFloat32, 1));
+  EXPECT_TRUE(test.AreAliases(kSimd128, 0, kFloat32, 2));
+  EXPECT_TRUE(test.AreAliases(kSimd128, 0, kFloat32, 3));
 
   EXPECT_FALSE(test.AreAliases(kFloat32, 0, kFloat64, 1));
   EXPECT_FALSE(test.AreAliases(kFloat32, 1, kFloat64, 1));
+  EXPECT_FALSE(test.AreAliases(kFloat32, 0, kSimd128, 1));
+  EXPECT_FALSE(test.AreAliases(kFloat32, 1, kSimd128, 1));
+  EXPECT_FALSE(test.AreAliases(kFloat64, 0, kSimd128, 1));
+  EXPECT_FALSE(test.AreAliases(kFloat64, 1, kSimd128, 1));
 
   EXPECT_TRUE(test.AreAliases(kFloat64, 0, kFloat32, 1));
   EXPECT_TRUE(test.AreAliases(kFloat64, 1, kFloat32, 2));
@@ -92,6 +120,12 @@ TEST_F(RegisterConfigurationUnitTest, Aliasing) {
   EXPECT_TRUE(test.AreAliases(kFloat64, 2, kFloat32, 4));
   EXPECT_TRUE(test.AreAliases(kFloat64, 2, kFloat32, 5));
 
+  EXPECT_TRUE(test.AreAliases(kSimd128, 0, kFloat64, 1));
+  EXPECT_TRUE(test.AreAliases(kSimd128, 1, kFloat64, 2));
+  EXPECT_TRUE(test.AreAliases(kSimd128, 1, kFloat64, 3));
+  EXPECT_TRUE(test.AreAliases(kSimd128, 2, kFloat64, 4));
+  EXPECT_TRUE(test.AreAliases(kSimd128, 2, kFloat64, 5));
+
   int alias_base_index = -1;
   EXPECT_EQ(test.GetAliases(kFloat32, 0, kFloat32, &alias_base_index), 1);
   EXPECT_EQ(alias_base_index, 0);
@@ -112,7 +146,7 @@ TEST_F(RegisterConfigurationUnitTest, Aliasing) {
   // Non-allocatable codes still alias.
   EXPECT_EQ(test.GetAliases(kFloat64, 2, kFloat32, &alias_base_index), 2);
   EXPECT_EQ(alias_base_index, 4);
-  // High numbered double registers don't alias nonexistent single registers.
+  // High numbered double and simd regs don't alias nonexistent float registers.
   EXPECT_EQ(
       test.GetAliases(kFloat64, RegisterConfiguration::kMaxFPRegisters / 2,
                       kFloat32, &alias_base_index),