commit bd78567cef305e35481734b7fc24f68ded031439
author Vladimir Marko <vmarko@google.com> Thu May 03 17:09:09 2018 +0100
committer Vladimir Marko <vmarko@google.com> Tue May 08 11:36:11 2018 +0100
tree e3873b73e3631c5cd70c1a3f8f38e79dad25d890
parent 9926e4615d75cb6c9371e1766a14b0a80089ae18

Store HIR type in HInstruction::packed_field_.

This is similar to
    https://android-review.googlesource.com/609566
though the performance impact has not been measured.
However, avoiding a virtual call reduces pressure on the
branch predictor and provides better optimization
opportunities for the C++ compiler.

As there is now no difference between HTemplateInstruction<>
and HExpression<> (the type is stored in HInstruction), we
remove the former and use HExpression<> for all instructions
that have a fixed number of inputs.

Test: Rely on TreeHugger.
Change-Id: Ib3fd111048b0ac38ee65386a7e5af70c5ccc98de

compiler/optimizing/nodes_vector.h

diff --git a/compiler/optimizing/nodes_vector.h b/compiler/optimizing/nodes_vector.h
index 1a484e1..c5e9a8d 100644
--- a/compiler/optimizing/nodes_vector.h
+++ b/compiler/optimizing/nodes_vector.h
@@ -79,13 +79,14 @@
                 size_t vector_length,
                 uint32_t dex_pc)
       : HVariableInputSizeInstruction(kind,
+                                      kSIMDType,
                                       side_effects,
                                       dex_pc,
                                       allocator,
                                       number_of_inputs,
                                       kArenaAllocVectorNode),
         vector_length_(vector_length) {
-    SetPackedField<TypeField>(packed_type);
+    SetPackedField<PackedTypeField>(packed_type);
     DCHECK_LT(1u, vector_length);
   }
 
@@ -99,14 +100,9 @@
     return vector_length_ * DataType::Size(GetPackedType());
   }
 
-  // Returns the type of the vector operation.
-  DataType::Type GetType() const OVERRIDE {
-    return kSIMDType;
-  }
-
   // Returns the true component type packed in a vector.
   DataType::Type GetPackedType() const {
-    return GetPackedField<TypeField>();
+    return GetPackedField<PackedTypeField>();
   }
 
   // Assumes vector nodes cannot be moved by default. Each concrete implementation
@@ -185,12 +181,12 @@
 
  protected:
   // Additional packed bits.
-  static constexpr size_t kFieldType = HInstruction::kNumberOfGenericPackedBits;
-  static constexpr size_t kFieldTypeSize =
+  static constexpr size_t kFieldPackedType = HInstruction::kNumberOfGenericPackedBits;
+  static constexpr size_t kFieldPackedTypeSize =
       MinimumBitsToStore(static_cast<size_t>(DataType::Type::kLast));
-  static constexpr size_t kNumberOfVectorOpPackedBits = kFieldType + kFieldTypeSize;
+  static constexpr size_t kNumberOfVectorOpPackedBits = kFieldPackedType + kFieldPackedTypeSize;
   static_assert(kNumberOfVectorOpPackedBits <= kMaxNumberOfPackedBits, "Too many packed fields.");
-  using TypeField = BitField<DataType::Type, kFieldType, kFieldTypeSize>;
+  using PackedTypeField = BitField<DataType::Type, kFieldPackedType, kFieldPackedTypeSize>;
 
   DEFAULT_COPY_CONSTRUCTOR(VecOperation);
 
@@ -358,11 +354,9 @@
     DCHECK(HasConsistentPackedTypes(input, packed_type));
     DCHECK_LT(index, vector_length);
     DCHECK_EQ(index, 0u);
-  }
-
-  // Yields a single component in the vector.
-  DataType::Type GetType() const OVERRIDE {
-    return GetPackedType();
+    // Yields a single component in the vector.
+    // Overrides the kSIMDType set by the VecOperation constructor.
+    SetPackedField<TypeField>(packed_type);
   }
 
   // An extract needs to stay in place, since SIMD registers are not