ART: Implement HSelect

This patch adds a new HIR instruction to Optimizing. HSelect returns
one of two inputs based on the outcome of a condition.

This is only initial implementation which:
 - defines the new instruction,
 - repurposes BooleanSimplifier to emit it,
 - extends InstructionSimplifier to statically resolve it,
 - updates existing code and tests accordingly.

Code generators currently emit fallback if/then/else code and will be
updated in follow-up CLs to use platform-specific conditional moves
when possible.

Change-Id: Ib61b17146487ebe6b55350c2b589f0b971dcaaee

1 files changed, 0 insertions, 81 deletions

diff --git a/compiler/optimizing/boolean_simplifier.h b/compiler/optimizing/boolean_simplifier.h
deleted file mode 100644
index e12a12c95b..0000000000
--- a/compiler/optimizing/boolean_simplifier.h
+++ /dev/null
@@ -1,81 +0,0 @@
-/*
- * Copyright (C) 2015 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-// This optimization recognizes two common patterns:
-//  (a) Boolean selection: Casting a boolean to an integer or negating it is
-//      carried out with an If statement selecting from zero/one integer
-//      constants. Because Boolean values are represented as zero/one, the
-//      pattern can be replaced with the condition instruction itself or its
-//      negation, depending on the layout.
-//  (b) Negated condition: Instruction simplifier may replace an If's condition
-//      with a boolean value. If this value is the result of a Boolean negation,
-//      the true/false branches can be swapped and negation removed.
-
-// Example: Negating a boolean value
-//     B1:
-//       z1   ParameterValue
-//       i2   IntConstant 0
-//       i3   IntConstant 1
-//       v4   Goto B2
-//     B2:
-//       z5   NotEquals [ z1 i2 ]
-//       v6   If [ z5 ] then B3 else B4
-//     B3:
-//       v7   Goto B5
-//     B4:
-//       v8   Goto B5
-//     B5:
-//       i9   Phi [ i3 i2 ]
-//       v10  Return [ i9 ]
-// turns into
-//     B1:
-//       z1   ParameterValue
-//       i2   IntConstant 0
-//       v4   Goto B2
-//     B2:
-//       z11  Equals [ z1 i2 ]
-//       v10  Return [ z11 ]
-//     B3, B4, B5: removed
-
-// Note: in order to recognize empty blocks, this optimization must be run
-// after the instruction simplifier has removed redundant suspend checks.
-
-#ifndef ART_COMPILER_OPTIMIZING_BOOLEAN_SIMPLIFIER_H_
-#define ART_COMPILER_OPTIMIZING_BOOLEAN_SIMPLIFIER_H_
-
-#include "optimization.h"
-
-namespace art {
-
-class HBooleanSimplifier : public HOptimization {
- public:
-  explicit HBooleanSimplifier(HGraph* graph)
-    : HOptimization(graph, kBooleanSimplifierPassName) {}
-
-  void Run() OVERRIDE;
-
-  static constexpr const char* kBooleanSimplifierPassName = "boolean_simplifier";
-
- private:
-  void TryRemovingNegatedCondition(HBasicBlock* block);
-  void TryRemovingBooleanSelection(HBasicBlock* block);
-
-  DISALLOW_COPY_AND_ASSIGN(HBooleanSimplifier);
-};
-
-}  // namespace art
-
-#endif  // ART_COMPILER_OPTIMIZING_BOOLEAN_SIMPLIFIER_H_