Add loop instructions to Stack IR

6 files changed, 57 insertions, 1 deletions

diff --git a/src/main/java/org/shedlang/compiler/patio/PatioCodeGen.java b/src/main/java/org/shedlang/compiler/patio/PatioCodeGen.java
index 57a08d69..c16dbc4a 100644
--- a/src/main/java/org/shedlang/compiler/patio/PatioCodeGen.java
+++ b/src/main/java/org/shedlang/compiler/patio/PatioCodeGen.java
@@ -366,6 +366,15 @@ public class PatioCodeGen {
                     (local, c) -> c.temporaryPopIntoLocal(local, localStore.source())
                 );
 
+            case LoopBreakInstruction loopBreakInstruction ->
+                throw new UnsupportedOperationException("TODO");
+
+            case LoopContinueInstruction loopContinueInstruction ->
+                throw new UnsupportedOperationException("TODO");
+
+            case LoopInstruction loopInstruction ->
+                throw new UnsupportedOperationException("TODO");
+
             case NamespaceFieldStoreInstruction namespaceFieldStore -> {
                 var fieldValueResult = context.temporaryPop();
                 var fieldValue = fieldValueResult.value();
diff --git a/src/main/java/org/shedlang/compiler/stackir/InstructionSerializer.java b/src/main/java/org/shedlang/compiler/stackir/InstructionSerializer.java
index 807caa57..1ae8f04d 100644
--- a/src/main/java/org/shedlang/compiler/stackir/InstructionSerializer.java
+++ b/src/main/java/org/shedlang/compiler/stackir/InstructionSerializer.java
@@ -113,6 +113,18 @@ public class InstructionSerializer {
                     treeIdentifier("local-store"),
                     treeString(localStoreInstruction.name())
                 );
+
+            case LoopInstruction loop ->
+                treeListIndented(
+                    treeIdentifier("loop"),
+                    instructionsToTree(loop.body())
+                );
+
+            case LoopBreakInstruction loopBreak ->
+                treeList(treeIdentifier("break"));
+
+            case LoopContinueInstruction loopContinue ->
+                treeList(treeIdentifier("continue"));
             
             case NamespaceFieldStoreInstruction namespaceFieldStore ->
                 treeList(
diff --git a/src/main/java/org/shedlang/compiler/stackir/instructions/Instruction.java b/src/main/java/org/shedlang/compiler/stackir/instructions/Instruction.java
index b4a59136..01af3588 100644
--- a/src/main/java/org/shedlang/compiler/stackir/instructions/Instruction.java
+++ b/src/main/java/org/shedlang/compiler/stackir/instructions/Instruction.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.stackir.instructions;
 import org.shedlang.compiler.sources.Source;
 
 public sealed interface Instruction
-    permits CallInstruction, DefineFunctionInstruction, DiscardInstruction, FieldLoadInstruction, IfInstruction, IntAddInstruction, IntEqualsInstruction, IntNotEqualInstruction, IntSubInstruction, LocalLoadInstruction, LocalStoreInstruction, NamespaceFieldStoreInstruction, NamespaceImportInstruction, PushBoolInstruction, PushIntInstruction, PushStringInstruction, PushUnitInstruction, ReturnInstruction, StringAddInstruction, VarLoadInstruction, VarStoreInstruction {
+    permits CallInstruction, DefineFunctionInstruction, DiscardInstruction, FieldLoadInstruction, IfInstruction, IntAddInstruction, IntEqualsInstruction, IntNotEqualInstruction, IntSubInstruction, LocalLoadInstruction, LocalStoreInstruction, LoopBreakInstruction, LoopContinueInstruction, LoopInstruction, NamespaceFieldStoreInstruction, NamespaceImportInstruction, PushBoolInstruction, PushIntInstruction, PushStringInstruction, PushUnitInstruction, ReturnInstruction, StringAddInstruction, VarLoadInstruction, VarStoreInstruction {
 
     Source source();
 }
diff --git a/src/main/java/org/shedlang/compiler/stackir/instructions/LoopBreakInstruction.java b/src/main/java/org/shedlang/compiler/stackir/instructions/LoopBreakInstruction.java
new file mode 100644
index 00000000..60a1d056
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/stackir/instructions/LoopBreakInstruction.java
@@ -0,0 +1,9 @@
+package org.shedlang.compiler.stackir.instructions;
+
+import org.shedlang.compiler.sources.Source;
+
+/**
+ * Jump to the end of the enclosing <code>loop</code> instruction's body.
+ */
+public record LoopBreakInstruction(Source source) implements Instruction {
+}
diff --git a/src/main/java/org/shedlang/compiler/stackir/instructions/LoopContinueInstruction.java b/src/main/java/org/shedlang/compiler/stackir/instructions/LoopContinueInstruction.java
new file mode 100644
index 00000000..d7111ea9
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/stackir/instructions/LoopContinueInstruction.java
@@ -0,0 +1,9 @@
+package org.shedlang.compiler.stackir.instructions;
+
+import org.shedlang.compiler.sources.Source;
+
+/**
+ * Jump to the start of the enclosing <code>loop</code> instruction's body.
+ */
+public record LoopContinueInstruction(Source source) implements Instruction {
+}
diff --git a/src/main/java/org/shedlang/compiler/stackir/instructions/LoopInstruction.java b/src/main/java/org/shedlang/compiler/stackir/instructions/LoopInstruction.java
new file mode 100644
index 00000000..119d9a52
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/stackir/instructions/LoopInstruction.java
@@ -0,0 +1,17 @@
+package org.shedlang.compiler.stackir.instructions;
+
+
+import org.shedlang.compiler.sources.Source;
+
+import java.util.List;
+
+/**
+ * Execute the body. The <code>continue</code> instruction can jump back to the
+ * start of the body. The <code>break</code> instruction can jump to the end of
+ * the body.
+ */
+public record LoopInstruction(
+    List<Instruction> body,
+    Source source
+) implements Instruction {
+}