From 89f835540b2ee466b1326528d3c50e0734d21ad1 Mon Sep 17 00:00:00 2001
From: Alexey Andreev <konsoletyper@gmail.com>
Date: Wed, 15 Feb 2017 22:16:14 +0300
Subject: [PATCH] Add unused variable elimination to standard optimization
 levels

---
 .../optimization/VariableEscapeAnalyzer.java  | 108 +-----------------
 core/src/main/java/org/teavm/vm/TeaVM.java    |   1 +
 2 files changed, 3 insertions(+), 106 deletions(-)

diff --git a/core/src/main/java/org/teavm/model/optimization/VariableEscapeAnalyzer.java b/core/src/main/java/org/teavm/model/optimization/VariableEscapeAnalyzer.java
index bd912112c..2a085925b 100644
--- a/core/src/main/java/org/teavm/model/optimization/VariableEscapeAnalyzer.java
+++ b/core/src/main/java/org/teavm/model/optimization/VariableEscapeAnalyzer.java
@@ -34,69 +34,13 @@ public final class VariableEscapeAnalyzer {
         return escaping;
     }
 
-    private static class InstructionAnalyzer implements InstructionVisitor {
+    private static class InstructionAnalyzer extends AbstractInstructionVisitor {
         private boolean[] escaping;
 
-        public InstructionAnalyzer(boolean[] escaping) {
+        InstructionAnalyzer(boolean[] escaping) {
             this.escaping = escaping;
         }
 
-        @Override
-        public void visit(EmptyInstruction insn) {
-        }
-
-        @Override
-        public void visit(ClassConstantInstruction insn) {
-        }
-
-        @Override
-        public void visit(NullConstantInstruction insn) {
-        }
-
-        @Override
-        public void visit(IntegerConstantInstruction insn) {
-        }
-
-        @Override
-        public void visit(LongConstantInstruction insn) {
-        }
-
-        @Override
-        public void visit(FloatConstantInstruction insn) {
-        }
-
-        @Override
-        public void visit(DoubleConstantInstruction insn) {
-        }
-
-        @Override
-        public void visit(StringConstantInstruction insn) {
-        }
-
-        @Override
-        public void visit(BinaryInstruction insn) {
-        }
-
-        @Override
-        public void visit(NegateInstruction insn) {
-        }
-
-        @Override
-        public void visit(AssignInstruction insn) {
-        }
-
-        @Override
-        public void visit(CastInstruction insn) {
-        }
-
-        @Override
-        public void visit(CastNumberInstruction insn) {
-        }
-
-        @Override
-        public void visit(CastIntegerInstruction insn) {
-        }
-
         @Override
         public void visit(BranchingInstruction insn) {
             escaping[insn.getOperand().getIndex()] = true;
@@ -108,10 +52,6 @@ public final class VariableEscapeAnalyzer {
             escaping[insn.getSecondOperand().getIndex()] = true;
         }
 
-        @Override
-        public void visit(JumpInstruction insn) {
-        }
-
         @Override
         public void visit(SwitchInstruction insn) {
             escaping[insn.getCondition().getIndex()] = true;
@@ -129,22 +69,6 @@ public final class VariableEscapeAnalyzer {
             escaping[insn.getException().getIndex()] = true;
         }
 
-        @Override
-        public void visit(ConstructArrayInstruction insn) {
-        }
-
-        @Override
-        public void visit(ConstructInstruction insn) {
-        }
-
-        @Override
-        public void visit(ConstructMultiArrayInstruction insn) {
-        }
-
-        @Override
-        public void visit(GetFieldInstruction insn) {
-        }
-
         @Override
         public void visit(PutFieldInstruction insn) {
             if (insn.getInstance() != null) {
@@ -153,22 +77,6 @@ public final class VariableEscapeAnalyzer {
             escaping[insn.getValue().getIndex()] = true;
         }
 
-        @Override
-        public void visit(ArrayLengthInstruction insn) {
-        }
-
-        @Override
-        public void visit(CloneArrayInstruction insn) {
-        }
-
-        @Override
-        public void visit(UnwrapArrayInstruction insn) {
-        }
-
-        @Override
-        public void visit(GetElementInstruction insn) {
-        }
-
         @Override
         public void visit(PutElementInstruction insn) {
             escaping[insn.getArray().getIndex()] = true;
@@ -196,18 +104,6 @@ public final class VariableEscapeAnalyzer {
             }
         }
 
-        @Override
-        public void visit(IsInstanceInstruction insn) {
-        }
-
-        @Override
-        public void visit(InitClassInstruction insn) {
-        }
-
-        @Override
-        public void visit(NullCheckInstruction insn) {
-        }
-
         @Override
         public void visit(MonitorEnterInstruction insn) {
             escaping[insn.getObjectRef().getIndex()] = true;
diff --git a/core/src/main/java/org/teavm/vm/TeaVM.java b/core/src/main/java/org/teavm/vm/TeaVM.java
index 6e5e1d3e6..72330e8b8 100644
--- a/core/src/main/java/org/teavm/vm/TeaVM.java
+++ b/core/src/main/java/org/teavm/vm/TeaVM.java
@@ -564,6 +564,7 @@ public class TeaVM implements TeaVMHost, ServiceRepository {
         }
         optimizations.add(new ClassInitElimination());
         optimizations.add(new UnreachableBasicBlockElimination());
+        optimizations.add(new UnusedVariableElimination());
         return optimizations;
     }