From 41290ab1cc8bf51487c44039f8510f43321aa93a Mon Sep 17 00:00:00 2001
From: "opencode-agent[bot]" <opencode-agent[bot]@users.noreply.github.com>
Date: Mon, 22 Jun 2026 11:56:30 +0000
Subject: [PATCH] =?UTF-8?q?All=20three=20JNode=20compilers=20(l1a,=20l1b,?=
 =?UTF-8?q?=20l2)=20=E2=9C=85=20PASS=20for=20iconst=5F4=20spec=20complianc?=
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Co-authored-by: LSantha <LSantha@users.noreply.github.com>
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 iconst_4_spec_compliance.md | 58 +++++++++++++++++++++++++++++++++++++
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+## Spec compliance report
+
+| Compiler | Status | Issues |
+|----------|--------|--------|
+| l1a | ✅ PASS | None |
+| l1b | ✅ PASS | None |
+| l2 | ✅ PASS | None |
+
+---
+
+## Details
+
+### l1a Implementation
+- **Status:** ✅ PASS
+- **Files:** `core/src/core/org/jnode/vm/x86/compiler/l1a/X86BytecodeVisitor.java:2161`, `core/src/core/org/jnode/vm/x86/compiler/l1a/ItemFactory.java:61`, `core/src/core/org/jnode/vm/x86/compiler/l1a/IntItem.java:60`, `core/src/core/org/jnode/vm/x86/compiler/l1a/Item.java:250`
+- **Issues:** None
+
+**Analysis:** 
+- BytecodeParser (line 174) correctly decodes opcode 0x07 → `handler.visit_iconst(4)`
+- X86BytecodeVisitor.visit_iconst() pushes an IntItem with JvmType.INT via ItemFactory.createIConst()
+- IntItem.getType() returns JvmType.INT (category 1)
+- Item.getCategory() returns 1 (correct for int)
+- VirtualStack correctly tracks the single-slot push
+
+### l1b Implementation
+- **Status:** ✅ PASS
+- **Files:** `core/src/core/org/jnode/vm/x86/compiler/l1b/X86BytecodeVisitor.java:2604`, `core/src/core/org/jnode/vm/x86/compiler/l1b/ItemFactory.java:56`, `core/src/core/org/jnode/vm/x86/compiler/l1b/IntItem.java:61`, `core/src/core/org/jnode/vm/x86/compiler/l1b/Item.java:235`
+- **Issues:** None
+
+**Analysis:**
+- Identical implementation pattern to l1a
+- Adds bytecode counter for profiling
+- IntItem extends WordItem with JvmType.INT, category 1
+- VirtualStack correctly handles the push
+
+### l2 Implementation
+- **Status:** ✅ PASS
+- **Files:** `core/src/core/org/jnode/vm/compiler/ir/IRGenerator.java:275`, `core/src/core/org/jnode/vm/x86/compiler/l2/GenericX86CodeGenerator.java:241`, `core/src/core/org/jnode/vm/compiler/ir/IntConstant.java:26`
+- **Issues:** None
+
+**Analysis:**
+- IRGenerator.visit_iconst() creates ConstantRefAssignQuad with IntConstant(value)
+- Stack offset incremented by 1 (category 1)
+- GenericX86CodeGenerator.generateCodeFor(ConstantRefAssignQuad) emits MOV_Const to register or stack
+- L2ByteCodeSupportChecker does not override visit_iconst (inherits empty impl from BytecodeVisitorSupport) — this is correct as the checker only validates L2 eligibility, actual compilation uses IRGenerator
+
+---
+
+## JVM Spec References
+- **Spec Base:** https://docs.oracle.com/javase/specs/jvms/se6/html/Instructions.doc.html
+- **Spec Page:** https://docs.oracle.com/javase/specs/jvms/se6/html/Instructions2.doc6.html#iconst
+- **Operation:** Push `int` constant
+- **Format:** `iconst_<i>`
+- **Forms:** `iconst_4` = 7 (0x7)
+- **Operand Stack:** `...` → `..., <i>`
+- **Description:** Push the `int` constant `<i>` (-1, 0, 1, 2, 3, 4 or 5) onto the operand stack
+- **Notes:** Equivalent to `bipush <i>` except operand is implicit
+- **Category:** 1 (int is a category-1 computational type per JVM Spec §2.11.1)
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