diff --git a/core/src/main/java/org/teavm/backend/wasm/generate/WasmGenerationVisitor.java b/core/src/main/java/org/teavm/backend/wasm/generate/WasmGenerationVisitor.java
index 270d27af1..a4f4d8b7b 100644
--- a/core/src/main/java/org/teavm/backend/wasm/generate/WasmGenerationVisitor.java
+++ b/core/src/main/java/org/teavm/backend/wasm/generate/WasmGenerationVisitor.java
@@ -1451,7 +1451,7 @@ class WasmGenerationVisitor implements StatementVisitor, ExprVisitor {
         expr.getIndex().acceptVisitor(this);
     }
 
-    private WasmExpression negate(WasmExpression expr) {
+    private static WasmExpression negate(WasmExpression expr) {
         if (expr instanceof WasmIntBinary) {
             WasmIntBinary binary = (WasmIntBinary) expr;
             if (binary.getType() == WasmIntType.INT32 && binary.getOperation() == WasmIntBinaryOperation.XOR) {
@@ -1478,11 +1478,11 @@ class WasmGenerationVisitor implements StatementVisitor, ExprVisitor {
         return new WasmIntBinary(WasmIntType.INT32, WasmIntBinaryOperation.EQ, expr, new WasmInt32Constant(0));
     }
 
-    private boolean isOne(WasmExpression expression) {
+    private static boolean isOne(WasmExpression expression) {
         return expression instanceof WasmInt32Constant && ((WasmInt32Constant) expression).getValue() == 1;
     }
 
-    private boolean isZero(WasmExpression expression) {
+    private static boolean isZero(WasmExpression expression) {
         return expression instanceof WasmInt32Constant && ((WasmInt32Constant) expression).getValue() == 0;
     }
 
@@ -1546,7 +1546,7 @@ class WasmGenerationVisitor implements StatementVisitor, ExprVisitor {
         return expression;
     }
 
-    private WasmIntBinaryOperation negate(WasmIntBinaryOperation op) {
+    private static WasmIntBinaryOperation negate(WasmIntBinaryOperation op) {
         switch (op) {
             case EQ:
                 return WasmIntBinaryOperation.NE;
@@ -1573,7 +1573,7 @@ class WasmGenerationVisitor implements StatementVisitor, ExprVisitor {
         }
     }
 
-    private WasmFloatBinaryOperation negate(WasmFloatBinaryOperation op) {
+    private static WasmFloatBinaryOperation negate(WasmFloatBinaryOperation op) {
         switch (op) {
             case EQ:
                 return WasmFloatBinaryOperation.NE;
diff --git a/core/src/main/java/org/teavm/backend/wasm/intrinsics/DoubleIntrinsic.java b/core/src/main/java/org/teavm/backend/wasm/intrinsics/DoubleIntrinsic.java
index e6756d460..b4d768ef2 100644
--- a/core/src/main/java/org/teavm/backend/wasm/intrinsics/DoubleIntrinsic.java
+++ b/core/src/main/java/org/teavm/backend/wasm/intrinsics/DoubleIntrinsic.java
@@ -47,6 +47,7 @@ public class DoubleIntrinsic implements WasmIntrinsic {
             case "getNaN":
             case "isNaN":
             case "isInfinite":
+            case "isFinite":
             case "doubleToLongBits":
             case "longBitsToDouble":
                 return true;
@@ -65,7 +66,14 @@ public class DoubleIntrinsic implements WasmIntrinsic {
                         WasmIntBinaryOperation.NE);
             case "isInfinite":
                 return testSpecialIEEE(manager.generate(invocation.getArguments().get(0)), manager,
-                    WasmIntBinaryOperation.EQ);
+                        WasmIntBinaryOperation.NE);
+            case "isFinite": {
+                WasmExpression result = testSpecialIEEE(manager.generate(invocation.getArguments().get(0)), manager,
+                        WasmIntBinaryOperation.NE);
+                result = new WasmIntBinary(WasmIntType.INT32, WasmIntBinaryOperation.EQ, result,
+                        new WasmInt32Constant(0));
+                return result;
+            }
             case "doubleToLongBits": {
                 WasmConversion conversion = new WasmConversion(WasmType.FLOAT64, WasmType.INT64, false,
                         manager.generate(invocation.getArguments().get(0)));
diff --git a/core/src/main/java/org/teavm/backend/wasm/intrinsics/FloatIntrinsic.java b/core/src/main/java/org/teavm/backend/wasm/intrinsics/FloatIntrinsic.java
index bf7c4076e..f897ec4f2 100644
--- a/core/src/main/java/org/teavm/backend/wasm/intrinsics/FloatIntrinsic.java
+++ b/core/src/main/java/org/teavm/backend/wasm/intrinsics/FloatIntrinsic.java
@@ -46,6 +46,7 @@ public class FloatIntrinsic implements WasmIntrinsic {
             case "getNaN":
             case "isNaN":
             case "isInfinite":
+            case "isFinite":
             case "floatToIntBits":
             case "intBitsToFloat":
                 return true;
@@ -65,6 +66,13 @@ public class FloatIntrinsic implements WasmIntrinsic {
             case "isInfinite":
                 return testSpecialIEEE(manager.generate(invocation.getArguments().get(0)), manager,
                     WasmIntBinaryOperation.EQ);
+            case "isFinite": {
+                WasmExpression result = testSpecialIEEE(manager.generate(invocation.getArguments().get(0)), manager,
+                        WasmIntBinaryOperation.EQ);
+                result = new WasmIntBinary(WasmIntType.INT32, WasmIntBinaryOperation.EQ, result,
+                        new WasmInt32Constant(0));
+                return result;
+            }
             case "floatToIntBits": {
                 WasmConversion conversion = new WasmConversion(WasmType.FLOAT32, WasmType.INT32, false,
                         manager.generate(invocation.getArguments().get(0)));
diff --git a/core/src/main/resources/org/teavm/backend/wasm/wasm-runtime.c b/core/src/main/resources/org/teavm/backend/wasm/wasm-runtime.c
index 647307fc1..3b7da14a9 100644
--- a/core/src/main/resources/org/teavm/backend/wasm/wasm-runtime.c
+++ b/core/src/main/resources/org/teavm/backend/wasm/wasm-runtime.c
@@ -16,9 +16,6 @@ float teavm_teavm_getNaN() {
     return NAN;
 }
 
-#define teavm_isnan isnan
-#define teavm_isinf isinf
-#define teavm_isfinite isfinite
 #define teavmMath_sin sin
 #define teavmMath_cos cos
 #define teavmMath_sqrt sqrt
diff --git a/core/src/main/resources/org/teavm/backend/wasm/wasm-runtime.js b/core/src/main/resources/org/teavm/backend/wasm/wasm-runtime.js
index d1ca9edad..f6b938ba2 100644
--- a/core/src/main/resources/org/teavm/backend/wasm/wasm-runtime.js
+++ b/core/src/main/resources/org/teavm/backend/wasm/wasm-runtime.js
@@ -39,12 +39,6 @@ TeaVM.wasm = function() {
             putwchar(memory[buffer++]);
         }
     }
-    function towlower(code) {
-        return String.fromCharCode(code).toLowerCase().charCodeAt(0);
-    }
-    function towupper(code) {
-        return String.fromCharCode(code).toUpperCase().charCodeAt(0);
-    }
     function currentTimeMillis() {
         return new Date().getTime();
     }
@@ -94,14 +88,8 @@ TeaVM.wasm = function() {
         obj.teavm = {
             currentTimeMillis: currentTimeMillis,
             nanoTime: function() { return performance.now(); },
-            isnan: isNaN,
-            teavm_getNaN: function() { return NaN; },
-            isinf: function(n) { return !isFinite(n) },
-            isfinite: isFinite,
             putwcharsOut: (chars, count) => putwchars(controller, chars, count),
             putwcharsErr: (chars, count) => putwchars(controller, chars, count),
-            towlower: towlower,
-            towupper: towupper,
             getNativeOffset: getNativeOffset,
             logString: string => logString(string, controller),
             logInt: logInt,