Update Patio if to support results

6 files changed, 62 insertions, 16 deletions

diff --git a/src/main/java/org/shedlang/compiler/backends/llvm/LlvmPatioCodeGen.java b/src/main/java/org/shedlang/compiler/backends/llvm/LlvmPatioCodeGen.java
index 8d9127f6..43e40d10 100644
--- a/src/main/java/org/shedlang/compiler/backends/llvm/LlvmPatioCodeGen.java
+++ b/src/main/java/org/shedlang/compiler/backends/llvm/LlvmPatioCodeGen.java
@@ -286,13 +286,13 @@ public class LlvmPatioCodeGen {
                 ));
 
                 context = context.setBasicBlockLabel(ifTrueLabel.name());
-                context = generateInstructions(patioIf.trueBody(), context);
+                context = generateInstructions(patioIf.trueBody().body(), context);
                 // TODO: remove this hack!
                 var ifTrueEndLabel = context.basicBlockLabel.orElseThrow();
                 context = context.addTerminatorInstruction(new LlvmBrUnconditional(endLabel.name()));
 
                 context = context.setBasicBlockLabel(ifFalseLabel.name());
-                context = generateInstructions(patioIf.falseBody(), context);
+                context = generateInstructions(patioIf.falseBody().body(), context);
                 // TODO: remove this hack!
                 var ifFalseEndLabel = context.basicBlockLabel.orElseThrow();
                 context = context.addTerminatorInstruction(new LlvmBrUnconditional(endLabel.name()));
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/WasmPatioCodeGen.java b/src/main/java/org/shedlang/compiler/backends/wasm/WasmPatioCodeGen.java
index 43a7dadf..6ec4e39f 100644
--- a/src/main/java/org/shedlang/compiler/backends/wasm/WasmPatioCodeGen.java
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/WasmPatioCodeGen.java
@@ -188,12 +188,12 @@ public class WasmPatioCodeGen {
                 context = generateOperand(patioIf.condition(), context);
 
                 context = context.enterBlock();
-                context = generateInstructions(patioIf.trueBody(), context);
+                context = generateInstructions(patioIf.trueBody().body(), context);
                 var wasmTrueBody = context.instructions;
                 context = context.exitBlock();
 
                 context = context.enterBlock();
-                context = generateInstructions(patioIf.falseBody(), context);
+                context = generateInstructions(patioIf.falseBody().body(), context);
                 var wasmFalseBody = context.instructions;
                 context = context.exitBlock();
 
diff --git a/src/main/java/org/shedlang/compiler/patio/PatioCodeGenNamespaces.java b/src/main/java/org/shedlang/compiler/patio/PatioCodeGenNamespaces.java
index 33bc3b62..afec18f4 100644
--- a/src/main/java/org/shedlang/compiler/patio/PatioCodeGenNamespaces.java
+++ b/src/main/java/org/shedlang/compiler/patio/PatioCodeGenNamespaces.java
@@ -91,15 +91,24 @@ public class PatioCodeGenNamespaces {
                 ));
 
                 importContext = importContext.addInstruction(new PatioIf(
-                    isInited,
                     List.of(),
-                    List.of(
-                        new PatioCall(
-                            Optional.empty(),
-                            globalNameNamespaceInit(namespaceName),
-                            List.of(),
-                            source
-                        )
+                    isInited,
+                    new PatioBlock(
+                        List.of(),
+                        List.of(),
+                        source
+                    ),
+                    new PatioBlock(
+                        List.of(
+                            new PatioCall(
+                                Optional.empty(),
+                                globalNameNamespaceInit(namespaceName),
+                                List.of(),
+                                source
+                            )
+                        ),
+                        List.of(),
+                        source
                     ),
                     source
                 ));
diff --git a/src/main/java/org/shedlang/compiler/patio/ast/PatioSerializer.java b/src/main/java/org/shedlang/compiler/patio/ast/PatioSerializer.java
index 530a95f0..0154d11b 100644
--- a/src/main/java/org/shedlang/compiler/patio/ast/PatioSerializer.java
+++ b/src/main/java/org/shedlang/compiler/patio/ast/PatioSerializer.java
@@ -186,9 +186,14 @@ public class PatioSerializer {
             case PatioIf if_ ->
                 treeListIndented(
                     treeIdentifier("if"),
+                    treeList(
+                        if_.targets().stream()
+                            .map(target -> operandToTree(target))
+                            .toList()
+                    ),
                     operandToTree(if_.condition()),
-                    instructionsToTree(if_.trueBody()),
-                    instructionsToTree(if_.falseBody())
+                    blockToTree(if_.trueBody()),
+                    blockToTree(if_.falseBody())
                 );
 
             case PatioIntAdd intAdd ->
@@ -262,6 +267,21 @@ public class PatioSerializer {
         };
     }
 
+    private static Tree blockToTree(PatioBlock block) {
+        return treeListIndented(
+            treeIdentifier("block"),
+            instructionsToTree(block.body()),
+            treeNamed(
+                "results",
+                treeList(
+                    block.results().stream()
+                        .map(result -> operandToTree(result))
+                        .toList()
+                )
+            )
+        );
+    }
+
     private static Tree localToTree(PatioLocal local) {
         return treeList(treeString(local.name()), typeToTree(local.type()));
     }
diff --git a/src/main/java/org/shedlang/compiler/patio/ast/instructions/PatioBlock.java b/src/main/java/org/shedlang/compiler/patio/ast/instructions/PatioBlock.java
new file mode 100644
index 00000000..8eecfa84
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/patio/ast/instructions/PatioBlock.java
@@ -0,0 +1,13 @@
+package org.shedlang.compiler.patio.ast.instructions;
+
+import org.shedlang.compiler.patio.ast.operands.PatioOperand;
+import org.shedlang.compiler.sources.Source;
+
+import java.util.List;
+
+public record PatioBlock(
+    List<PatioInstruction> body,
+    List<PatioOperand> results,
+    Source source
+) {
+}
diff --git a/src/main/java/org/shedlang/compiler/patio/ast/instructions/PatioIf.java b/src/main/java/org/shedlang/compiler/patio/ast/instructions/PatioIf.java
index 87de0735..4f7a8700 100644
--- a/src/main/java/org/shedlang/compiler/patio/ast/instructions/PatioIf.java
+++ b/src/main/java/org/shedlang/compiler/patio/ast/instructions/PatioIf.java
@@ -8,11 +8,15 @@ import java.util.List;
 /**
  * If the condition is true, execute the instructions in the "true" body,
  * otherwise execute the instructions in the "false" body.
+ *
+ * Each block must return the same number of results as targets. Each result
+ * is assigned to the target with the same index.
  */
 public record PatioIf(
+    List<PatioLocalRef> targets,
     PatioLocalRef condition,
-    List<PatioInstruction> trueBody,
-    List<PatioInstruction> falseBody,
+    PatioBlock trueBody,
+    PatioBlock falseBody,
     Source source
 ) implements PatioInstruction {
 }