SIMD plumbing

runtime/vm/locations.h

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_LOCATIONS_H_
 #define VM_LOCATIONS_H_
 
 #include "vm/allocation.h"
 #include "vm/assembler.h"
 #include "vm/bitfield.h"
 
 namespace dart {
 
 class BufferFormatter;
 class Value;
 
 // Location objects are used to connect register allocator and code generator.
 // Instruction templates used by code generator have a corresponding
 // LocationSummary object which specifies expected location for every input
 // and output.
 // Each location is encoded as a single word: for non-constant locations
 // low 3 bits denote location kind, rest is kind specific location payload
 // e.g. for REGISTER kind payload is register code (value of the Register
 // enumeration), constant locations contain a tagged (low 2 bits are set to 01)
 // Object handle
 class Location : public ValueObject {
  private:
   enum {
     // Number of bits required to encode Kind value.
-    kBitsForKind = 3,
+    kBitsForKind = 4,
     kBitsForPayload = kWordSize * kBitsPerByte - kBitsForKind,
   };
 
   static const uword kInvalidLocation = 0;
   static const uword kConstantMask = 0x3;
 
   static const intptr_t kMachineRegisterMask = 0x6;
   static const intptr_t kMachineRegister = 0x6;
 
  public:
@@ skipping 10 matching lines @@
     // Unallocated location represents a location that is not fixed and can be
     // allocated by a register allocator.  Each unallocated location has
     // a policy that specifies what kind of location is suitable. Payload
     // contains register allocation policy.
     kUnallocated = 2,
 
     // Spill slot allocated by the register allocator.  Payload contains
     // a spill index.
     kStackSlot = 3,
     kDoubleStackSlot = 4,
+    kFloat32x4StackSlot = 8,
+    kUint32x4StackSlot = 9,

[Vyacheslav Egorov (Google), 2013/03/17 18:17:10]

It can't be 9 (see the comment above enum Kind).

[Cutch, 2013/03/17 21:52:37]

Done.

 
     // Register location represents a fixed register.  Payload contains
     // register code.
     kRegister = 6,
 
     // FpuRegister location represents a fixed fpu register.  Payload contains
     // its code.
     kFpuRegister = 7,
   };
 
@@ skipping 98 matching lines @@
 
   bool IsRegister() const {
     return kind() == kRegister;
   }
 
   Register reg() const {
     ASSERT(IsRegister());
     return RegisterField::decode(payload());
   }
 
-  // FPU registers and double spill slots can contain either doubles
-  // or 64-bit integers.
+  // FPU registers and double spill slots can contain either doubles,
+  // 64-bit integers, Float32x4, or Uint32x4 values.
   enum Representation {
     kDouble,
-    kMint
+    kMint,
+    kFloat32x4,
+    kUint32x4
   };
 
   Representation representation() const {
-    ASSERT(IsFpuRegister() || IsDoubleStackSlot());
+    ASSERT(IsFpuRegister() ||IsDoubleStackSlot() || IsFloat32x4StackSlot() ||
+           IsUint32x4StackSlot());
     return RepresentationField::decode(payload());
   }
 
   // FpuRegister locations.
   static Location FpuRegisterLocation(FpuRegister reg, Representation rep) {
     uword payload =
         FpuRegisterField::encode(reg) | RepresentationField::encode(rep);
     return Location(kFpuRegister, payload);
   }
 
@@ skipping 57 matching lines @@
     Location loc(kDoubleStackSlot, payload);
     // Ensure that sign is preserved.
     ASSERT(loc.stack_index() == stack_index);
     return loc;
   }
 
   bool IsDoubleStackSlot() const {
     return kind() == kDoubleStackSlot;
   }
 
+  static Location Float32x4StackSlot(intptr_t stack_index, Representation rep) {
+    ASSERT((-kStackIndexBias <= stack_index) &&
+           (stack_index < kStackIndexBias));
+    uword payload =
+        IndexField::encode(static_cast<uword>(kStackIndexBias + stack_index))

[Vyacheslav Egorov (Google), 2013/03/17 18:17:10]

encoding of stack indexes repeats multiple times. consider introducing a helper.

[Cutch, 2013/03/17 21:52:37]

Done.

+      | RepresentationField::encode(rep);
+    Location loc(kFloat32x4StackSlot, payload);
+    // Ensure that sign is preserved.
+    ASSERT(loc.stack_index() == stack_index);
+    return loc;
+  }
+
+  bool IsFloat32x4StackSlot() const {
+    return kind() == kFloat32x4StackSlot;
+  }
+
+  static Location Uint32x4StackSlot(intptr_t stack_index, Representation rep) {
+    ASSERT((-kStackIndexBias <= stack_index) &&
+           (stack_index < kStackIndexBias));
+    uword payload =
+        IndexField::encode(static_cast<uword>(kStackIndexBias + stack_index))
+      | RepresentationField::encode(rep);
+    Location loc(kUint32x4StackSlot, payload);
+    // Ensure that sign is preserved.
+    ASSERT(loc.stack_index() == stack_index);
+    return loc;
+  }
+
+  bool IsUint32x4StackSlot() const {
+    return kind() == kUint32x4StackSlot;
+  }
+
 
   intptr_t stack_index() const {
-    ASSERT(IsStackSlot() || IsDoubleStackSlot());
+    ASSERT(IsStackSlot() || IsDoubleStackSlot() || IsFloat32x4StackSlot() ||
+           IsUint32x4StackSlot());
     // Decode stack index manually to preserve sign.
     return IndexField::decode(payload()) - kStackIndexBias;
   }
 
   // Return a memory operand for stack slot locations.
   Address ToStackSlotAddress() const;
 
   // Constants.
   static Location RegisterOrConstant(Value* value);
   static Location RegisterOrSmiConstant(Value* value);
@@ skipping 27 matching lines @@
   }
 
   typedef BitField<Kind, 0, kBitsForKind> KindField;
   typedef BitField<uword, kBitsForKind, kBitsForPayload> PayloadField;
 
   // Layout for kUnallocated locations payload.
   typedef BitField<Policy, 0, 3> PolicyField;
 
   // Layout for register locations payload. The representation bit is only used
   // for FpuRegister and unused for Register.
-  static const intptr_t kBitsForRepresentation = 1;
+  static const intptr_t kBitsForRepresentation = 2;
   static const intptr_t kBitsForRegister =
       kBitsForPayload - kBitsForRepresentation;
   typedef BitField<Representation,
                    0,
                    kBitsForRepresentation> RepresentationField;
   typedef BitField<Register,
                    kBitsForRepresentation,
                    kBitsForRegister> RegisterField;
   typedef BitField<FpuRegister,
                    kBitsForRepresentation,
@@ skipping 162 matching lines @@
   BitmapBuilder* stack_bitmap_;
 
   const ContainsCall contains_call_;
   RegisterSet live_registers_;
 };
 
 
 }  // namespace dart
 
 #endif  // VM_LOCATIONS_H_