Add WASM call instruction

6 files changed, 49 insertions, 5 deletions

diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/instructions/WasmCall.java b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/instructions/WasmCall.java
new file mode 100644
index 00000000..29f2ff7e
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/instructions/WasmCall.java
@@ -0,0 +1,8 @@
+package org.shedlang.compiler.backends.wasm.structure.ast.instructions;
+
+import org.shedlang.compiler.backends.wasm.structure.ast.modules.WasmFuncName;
+
+public record WasmCall(
+    WasmFuncName funcName
+) implements WasmInstruction {
+}
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/instructions/WasmInstruction.java b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/instructions/WasmInstruction.java
index 65b4b672..e0bce7b5 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/instructions/WasmInstruction.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/instructions/WasmInstruction.java
@@ -1,4 +1,4 @@
 package org.shedlang.compiler.backends.wasm.structure.ast.instructions;
 
-public sealed interface WasmInstruction permits WasmCallIndirect, WasmDrop, WasmI32Const, WasmI32Load, WasmI64Const, WasmLocalGet, WasmLocalSet, WasmMemoryAddressConst, WasmReturn {
+public sealed interface WasmInstruction permits WasmCall, WasmCallIndirect, WasmDrop, WasmI32Const, WasmI32Load, WasmI64Const, WasmLocalGet, WasmLocalSet, WasmMemoryAddressConst, WasmReturn {
 }
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/linking/WasmRelocatableIndex.java b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/linking/WasmRelocatableIndex.java
index 3801bf59..90989b14 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/linking/WasmRelocatableIndex.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/linking/WasmRelocatableIndex.java
@@ -3,6 +3,7 @@ package org.shedlang.compiler.backends.wasm.structure.ast.linking;
 import org.shedlang.compiler.backends.wasm.structure.ast.types.WasmFuncType;
 
 public sealed interface WasmRelocatableIndex {
+    record FuncIndex(String name) implements WasmRelocatableIndex {}
     record MemoryAddress(WasmMemoryAddress address) implements WasmRelocatableIndex {}
     record TypeIndex(WasmFuncType funcType) implements WasmRelocatableIndex {}
 }
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryFormatInstructions.java b/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryFormatInstructions.java
index 4bfae740..aa2fff35 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryFormatInstructions.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryFormatInstructions.java
@@ -25,6 +25,11 @@ public class WasmBinaryFormatInstructions {
                 writer.writeByte(0x0f);
             }
 
+            case WasmCall call -> {
+                writer.writeByte(0x10);
+                writer.writeFuncIndex(call.funcName());
+            }
+
             case WasmCallIndirect callIndirect -> {
                 writer.writeByte(0x11);
                 writer.writeTypeIndex(callIndirect.funcType());
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryFormatLinking.java b/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryFormatLinking.java
index fb5ea132..5e8a9425 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryFormatLinking.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryFormatLinking.java
@@ -69,6 +69,9 @@ public class WasmBinaryFormatLinking {
         WasmBinaryWriter writer
     ) {
         var index = switch (relocationEntry.index()) {
+            case WasmRelocatableIndex.FuncIndex funcIndex ->
+                symbolTable.funcNameToFuncIndex(funcIndex.name()).value();
+
             case WasmRelocatableIndex.MemoryAddress memoryAddress ->
                 symbolTable.memoryAddressToSymbolIndex(memoryAddress.address()).value();
 
@@ -229,17 +232,20 @@ public class WasmBinaryFormatLinking {
         private final int functionSymbolIndexOffset;
         private final Map<WasmMemoryAddress, WasmSymbolIndex> memoryAddressToSymbolIndex;
         private final Map<WasmFuncType, WasmTypeIndex> funcTypeToTypeIndex;
+        private final Map<String, WasmSymbolIndex> funcNameToSymbolIndex;
 
         public SymbolTable(
             List<SymbolInfo> symbolInfos,
             int functionSymbolIndexOffset,
             Map<WasmMemoryAddress, WasmSymbolIndex> memoryAddressToSymbolIndex,
-            Map<WasmFuncType, WasmTypeIndex> funcTypeToTypeIndex
+            Map<WasmFuncType, WasmTypeIndex> funcTypeToTypeIndex,
+            Map<String, WasmSymbolIndex> funcNameToSymbolIndex
         ) {
             this.symbolInfos = symbolInfos;
             this.functionSymbolIndexOffset = functionSymbolIndexOffset;
             this.memoryAddressToSymbolIndex = memoryAddressToSymbolIndex;
             this.funcTypeToTypeIndex = funcTypeToTypeIndex;
+            this.funcNameToSymbolIndex = funcNameToSymbolIndex;
         }
 
         public WasmSymbolIndex funcIndexToSymbolIndex(WasmFuncIndex funcIndex) {
@@ -265,6 +271,16 @@ public class WasmBinaryFormatLinking {
                 return typeIndex;
             }
         }
+
+        public WasmSymbolIndex funcNameToFuncIndex(String name) {
+            var syjmbolIndex = funcNameToSymbolIndex.get(name);
+            if (syjmbolIndex == null) {
+                // TODO: better error
+                throw new RuntimeException("could not find index for func: " + name);
+            } else {
+                return syjmbolIndex;
+            }
+        }
     }
     
     private static SymbolTable generateSymbolTable(WasmModule module) {
@@ -272,6 +288,7 @@ public class WasmBinaryFormatLinking {
         var memoryAddressToSymbolIndex = new HashMap<WasmMemoryAddress, WasmSymbolIndex>();
 
         var functionSymbolIndexOffset = 0;
+        var funcNameToSymbolIndex = new HashMap<String, WasmSymbolIndex>();
         for (var function : module.indexedFunctions()) {
             var flags = switch (function) {
                 case WasmModule.IndexedFunction.Definition definition ->
@@ -285,17 +302,20 @@ public class WasmBinaryFormatLinking {
                 function.funcIndex(),
                 function.name()
             );
+            var symbolIndex = new WasmSymbolIndex(symbolInfos.size());
             symbolInfos.add(symbolInfo);
+            funcNameToSymbolIndex.put(function.name(), symbolIndex);
         }
 
         for (var dataSegment : module.dataSegments()) {
             for (var dataSymbol : dataSegment.symbols()) {
                 var symbolInfo = new SymbolInfo.Data(List.of(), dataSymbol);
+                var symbolIndex = new WasmSymbolIndex(symbolInfos.size());
+                symbolInfos.add(symbolInfo);
                 memoryAddressToSymbolIndex.put(
                     new WasmMemoryAddress(dataSymbol.dataSegmentIndex(), dataSymbol.offset()),
-                    new WasmSymbolIndex(symbolInfos.size())
+                    symbolIndex
                 );
-                symbolInfos.add(symbolInfo);
             }
         }
 
@@ -327,7 +347,8 @@ public class WasmBinaryFormatLinking {
             symbolInfos,
             functionSymbolIndexOffset,
             memoryAddressToSymbolIndex,
-            funcTypeToTypeIndex
+            funcTypeToTypeIndex,
+            funcNameToSymbolIndex
         );
     }
 
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryWriter.java b/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryWriter.java
index c14fd1db..6636c5d1 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryWriter.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryWriter.java
@@ -3,6 +3,7 @@ package org.shedlang.compiler.backends.wasm.structure.binary;
 import org.shedlang.compiler.backends.wasm.structure.BinaryWriter;
 import org.shedlang.compiler.backends.wasm.structure.ast.linking.WasmMemoryAddress;
 import org.shedlang.compiler.backends.wasm.structure.ast.linking.WasmRelocatableIndex;
+import org.shedlang.compiler.backends.wasm.structure.ast.modules.WasmFuncName;
 import org.shedlang.compiler.backends.wasm.structure.ast.modules.WasmTableIndex;
 import org.shedlang.compiler.backends.wasm.structure.ast.types.WasmFuncType;
 
@@ -47,6 +48,14 @@ public class WasmBinaryWriter {
         WasmBinaryFormatValues.writeString(value, writer);
     }
 
+    public void writeFuncIndex(WasmFuncName funcName) throws IOException {
+        writeRelocatableIndex(
+            WasmRelocationType.FUNCTION_INDEX_LEB,
+            () -> writePaddedUnsignedInt32(0),
+            new WasmRelocatableIndex.FuncIndex(funcName.value())
+        );
+    }
+
     public void writeMemoryAddressConst(WasmMemoryAddress index) throws IOException {
         writeRelocatableIndex(
             WasmRelocationType.MEMORY_ADDR_SLEB,