Generate WASM for string add

5 files changed, 51 insertions, 2 deletions

diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGen.java b/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGen.java
index dbf667c2..a9ee98ac 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGen.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGen.java
@@ -243,7 +243,7 @@ public class WasmCodeGen {
                 context.addInstruction(new WasmReturn());
 
             case StringAddInstruction stringAdd ->
-                throw new UnsupportedOperationException("TODO");
+                WasmCodeGenStrings.add(context);
         };
     }
 }
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGenAlloc.java b/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGenAlloc.java
index 9d74e60c..96363570 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGenAlloc.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGenAlloc.java
@@ -20,7 +20,7 @@ public class WasmCodeGenAlloc {
         return context
             .addImport(new WasmImport(
                 "env",
-                "shed__runtime__alloc",
+                allocName,
                 new WasmImportDescriptor.Func(
                     allocName,
                     new WasmFuncType(List.of(WasmValueType.I32), List.of(WasmValueType.I32))
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGenStrings.java b/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGenStrings.java
index a7266091..d596c53c 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGenStrings.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGenStrings.java
@@ -1,11 +1,17 @@
 package org.shedlang.compiler.backends.wasm;
 
+import org.shedlang.compiler.backends.wasm.structure.ast.instructions.WasmCall;
 import org.shedlang.compiler.backends.wasm.structure.ast.linking.WasmMemoryAddress;
 import org.shedlang.compiler.backends.wasm.structure.ast.modules.WasmAlignment;
+import org.shedlang.compiler.backends.wasm.structure.ast.modules.WasmFuncName;
+import org.shedlang.compiler.backends.wasm.structure.ast.modules.WasmImport;
+import org.shedlang.compiler.backends.wasm.structure.ast.modules.WasmImportDescriptor;
+import org.shedlang.compiler.backends.wasm.structure.ast.types.WasmFuncType;
 
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
 import java.nio.charset.StandardCharsets;
+import java.util.List;
 
 public class WasmCodeGenStrings {
     private WasmCodeGenStrings() {
@@ -27,4 +33,22 @@ public class WasmCodeGenStrings {
             WasmAlignment.ALIGN_32_BIT
         );
     }
+
+    public static WasmCodeGenContext add(WasmCodeGenContext context) {
+        var runtimeAddName = "shed__runtime__string_add";
+
+        return context
+            .addImport(new WasmImport(
+                "env",
+                runtimeAddName,
+                new WasmImportDescriptor.Func(
+                    runtimeAddName,
+                    new WasmFuncType(
+                        List.of(WasmCodeGenTypes.STRING_TYPE, WasmCodeGenTypes.STRING_TYPE),
+                        List.of(WasmCodeGenTypes.STRING_TYPE)
+                    )
+                )
+            ))
+            .addInstruction(new WasmCall(new WasmFuncName(runtimeAddName)));
+    }
 }
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGenTypes.java b/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGenTypes.java
index 5822f1b6..27010de9 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGenTypes.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/WasmCodeGenTypes.java
@@ -7,4 +7,5 @@ public class WasmCodeGenTypes {
     }
 
     public static final WasmValueType VALUE_TYPE = WasmValueType.I32;
+    public static final WasmValueType STRING_TYPE = VALUE_TYPE;
 }
diff --git a/src/test/java/org/shedlang/compiler/backends/wasm/WasmCodeGenStringAddTests.java b/src/test/java/org/shedlang/compiler/backends/wasm/WasmCodeGenStringAddTests.java
new file mode 100644
index 00000000..2e4d9ed6
--- /dev/null
+++ b/src/test/java/org/shedlang/compiler/backends/wasm/WasmCodeGenStringAddTests.java
@@ -0,0 +1,24 @@
+package org.shedlang.compiler.backends.wasm;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
+import org.shedlang.compiler.testing.snapshots.Snapshotter;
+
+import java.io.IOException;
+
+import static org.shedlang.compiler.backends.wasm.WasmCodeGenTesting.objdumpContext;
+
+@ExtendWith({SnapshotResolver.class})
+public class WasmCodeGenStringAddTests {
+    @Test
+    public void stringAddIsCompiledToCallToRuntimeStringAdd(Snapshotter snapshotter) throws IOException, InterruptedException {
+        var instruction = Instructions.stringAdd();
+        var context = WasmCodeGenContext.EMPTY;
+
+        var result = WasmCodeGen.generateInstruction(instruction, context);
+
+        snapshotter.assertSnapshot(objdumpContext(result));
+    }
+}