Write globals to symbol table

6 files changed, 79 insertions, 8 deletions

diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmGlobal.java b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmGlobal.java
index 637376c2..7b8835a6 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmGlobal.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmGlobal.java
@@ -3,5 +3,5 @@ package org.shedlang.compiler.backends.wasm.structure.ast.modules;
 import org.shedlang.compiler.backends.wasm.structure.ast.instructions.WasmExpression;
 import org.shedlang.compiler.backends.wasm.structure.ast.types.WasmGlobalType;
 
-public record WasmGlobal(WasmGlobalType type, WasmExpression init) {
+public record WasmGlobal(String name, WasmGlobalType type, WasmExpression init) {
 }
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmGlobalIndex.java b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmGlobalIndex.java
new file mode 100644
index 00000000..76a5728f
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmGlobalIndex.java
@@ -0,0 +1,4 @@
+package org.shedlang.compiler.backends.wasm.structure.ast.modules;
+
+public record WasmGlobalIndex(int value) {
+}
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmImportDescriptor.java b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmImportDescriptor.java
index 95e9c8cb..fa7aa10f 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmImportDescriptor.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmImportDescriptor.java
@@ -9,5 +9,5 @@ public sealed interface WasmImportDescriptor {
     record Func(String identifier, WasmFuncType type) implements WasmImportDescriptor {}
     record Table(WasmTableType type) implements WasmImportDescriptor {}
     record Memory(WasmMemoryType type) implements WasmImportDescriptor {}
-    record Global(WasmGlobalType type) implements WasmImportDescriptor {}
+    record Global(String identifier, WasmGlobalType type) implements WasmImportDescriptor {}
 }
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmModule.java b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmModule.java
index 79a1e6f5..5875a591 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmModule.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/structure/ast/modules/WasmModule.java
@@ -79,6 +79,43 @@ public record WasmModule(
         return indexedFunctions;
     }
 
+    public sealed interface IndexedGlobal {
+        record Import(WasmGlobalIndex globalIndex, WasmImportDescriptor.Global descriptor) implements IndexedGlobal {
+            @Override
+            public String name() {
+                return descriptor.identifier();
+            }
+        }
+
+        record Definition(WasmGlobalIndex globalIndex, WasmGlobal global) implements IndexedGlobal {
+            @Override
+            public String name() {
+                return global.name();
+            }
+        }
+
+        WasmGlobalIndex globalIndex();
+        String name();
+    }
+
+    public List<IndexedGlobal> indexedGlobals() {
+        var indexedGlobals = new ArrayList<IndexedGlobal>();
+
+        for (var import_ : imports) {
+            if (import_.descriptor() instanceof WasmImportDescriptor.Global global) {
+                var globalIndex = new WasmGlobalIndex(indexedGlobals.size());
+                indexedGlobals.add(new IndexedGlobal.Import(globalIndex, global));
+            }
+        }
+
+        for (var global : globals) {
+            var globalIndex = new WasmGlobalIndex(indexedGlobals.size());
+            indexedGlobals.add(new IndexedGlobal.Definition(globalIndex, global));
+        }
+
+        return indexedGlobals;
+    }
+
     public WasmModule addType(WasmFuncType type) {
         return new WasmModule(
             types.plus(type),
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 59bab46e..c92baba2 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
@@ -2,15 +2,16 @@ package org.shedlang.compiler.backends.wasm.structure.binary;
 
 import org.shedlang.compiler.backends.wasm.structure.BinaryWriter;
 import org.shedlang.compiler.backends.wasm.structure.ast.modules.WasmFuncIndex;
+import org.shedlang.compiler.backends.wasm.structure.ast.modules.WasmGlobalIndex;
 import org.shedlang.compiler.backends.wasm.structure.ast.modules.WasmModule;
 
 import java.io.IOException;
 import java.util.Collection;
 import java.util.List;
+import java.util.stream.Stream;
 
 import static org.shedlang.compiler.backends.wasm.structure.binary.WasmBinaryFormatConventions.writeVec;
-import static org.shedlang.compiler.backends.wasm.structure.binary.WasmBinaryFormatModules.writeCustomSection;
-import static org.shedlang.compiler.backends.wasm.structure.binary.WasmBinaryFormatModules.writeFuncIndex;
+import static org.shedlang.compiler.backends.wasm.structure.binary.WasmBinaryFormatModules.*;
 import static org.shedlang.compiler.backends.wasm.structure.binary.WasmBinaryFormatSize.writeSize;
 import static org.shedlang.compiler.backends.wasm.structure.binary.WasmBinaryFormatValues.writeString;
 
@@ -79,6 +80,12 @@ public class WasmBinaryFormatLinking {
                 writeFuncIndex(function.funcIndex, writer);
                 writeString(function.name(), writer);
             }
+            case SymbolInfo.Global global -> {
+                writer.writeByte(SymbolType.GLOBAL.id);
+                Leb128Encoding.encodeUnsignedInt32(flagsToInt(global.flags), writer);
+                writeGlobalIndex(global.globalIndex, writer);
+                writeString(global.name(), writer);
+            }
         }
     }
 
@@ -98,8 +105,8 @@ public class WasmBinaryFormatLinking {
     }
     
     private static List<SymbolInfo> symbolInfos(WasmModule module) {
-        return module.indexedFunctions().stream()
-            .<SymbolInfo>map(function -> {
+        var functionSymbols = module.indexedFunctions().stream()
+            .map(function -> {
                 var flags = switch (function) {
                     case WasmModule.IndexedFunction.Definition definition ->
                         List.<SymbolFlag>of();
@@ -112,13 +119,32 @@ public class WasmBinaryFormatLinking {
                     function.funcIndex(),
                     function.name()
                 );
-            })
-            .toList();
+            });
+
+        var globalSymbols = module.indexedGlobals().stream()
+            .map(global -> {
+                var flags = switch (global) {
+                    case WasmModule.IndexedGlobal.Definition definition ->
+                        List.<SymbolFlag>of();
+
+                    case WasmModule.IndexedGlobal.Import import_ ->
+                        List.of(SymbolFlag.UNDEFINED, SymbolFlag.EXPLICIT_NAME);
+                };
+                return new SymbolInfo.Global(
+                    flags,
+                    global.globalIndex(),
+                    global.name()
+                );
+            });
+
+        return Stream.<SymbolInfo>concat(functionSymbols, globalSymbols).toList();
     }
 
     private sealed interface SymbolInfo {
         record Function(List<SymbolFlag> flags, WasmFuncIndex funcIndex, String name) implements SymbolInfo {
+        }
 
+        record Global(List<SymbolFlag> flags, WasmGlobalIndex globalIndex, String name) implements SymbolInfo {
         }
     }
 
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryFormatModules.java b/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryFormatModules.java
index 3525bbe5..2f424d98 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryFormatModules.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/structure/binary/WasmBinaryFormatModules.java
@@ -36,6 +36,10 @@ public class WasmBinaryFormatModules {
         Leb128Encoding.encodeUnsignedInt32(funcIndex.value(), writer);
     }
 
+    static void writeGlobalIndex(WasmGlobalIndex globalIndex, BinaryWriter writer) {
+        Leb128Encoding.encodeUnsignedInt32(globalIndex.value(), writer);
+    }
+
     // == Sections ==
 
     interface Write {