fixes

crates/prometeu-compiler/src/building/linker.rs

@@ -255,14 +255,14 @@ impl Linker {
                             patch_u32_at(&mut combined_code, imm_start, &|_| global_func_idx);
                         }
                     }
-                    // Relocate intra-function control-flow immediates by module code offset to preserve absolute PCs
+                    // Branches are strictly function-relative. Do NOT relocate.
+                    // The emitter encodes `target_rel = label - func_start` and the verifier enforces it.
                     OpCode::Jmp | OpCode::JmpIfFalse | OpCode::JmpIfTrue => {
-                        // For branches, immediate must be present and represents rel PC from function start
                         let _ = imm_u32_opt.ok_or_else(|| LinkError::IncompatibleSymbolSignature(format!(
                             "Invalid branch immediate at pc {}",
                             pc - code_offset
                         )))?;
-                        patch_u32_at(&mut combined_code, imm_start, &|cur| cur + (code_offset as u32));
+                        // Intentionally no patch here.
                     }
                     _ => {}
                 }
@@ -628,16 +628,16 @@ mod tests {
         // Module 2's code starts after module 1's code
         let module2_offset = code1.len() as u32;
 
-        // Verify that the JMP immediate equals original_target (0) + module2_offset
+        // Verify that the JMP immediate remains function-relative (0), no relocation applied
         let jmp_abs_pc = module2_offset as usize + jmp_pc as usize;
         let jmp_imm_off = jmp_abs_pc + 2; // skip opcode
         let jmp_patched = u32::from_le_bytes(result.rom[jmp_imm_off..jmp_imm_off+4].try_into().unwrap());
-        assert_eq!(jmp_patched, module2_offset);
+        assert_eq!(jmp_patched, 0);
 
-        // Verify that the conditional JMP immediate was relocated similarly
+        // Verify that the conditional JMP immediate also remains function-relative (0)
         let cjmp_abs_pc = module2_offset as usize + cjmp_pc as usize;
         let cjmp_imm_off = cjmp_abs_pc + 2;
         let cjmp_patched = u32::from_le_bytes(result.rom[cjmp_imm_off..cjmp_imm_off+4].try_into().unwrap());
-        assert_eq!(cjmp_patched, module2_offset);
+        assert_eq!(cjmp_patched, 0);
     }
 }

crates/prometeu-vm/src/verifier.rs

@@ -139,7 +139,28 @@ impl Verifier {
                 let func_len = func_end_abs - func_start;
 
                 if target_rel > func_len {
-                    return Err(VerifierError::InvalidJumpTarget { pc: func_start + pc, target: func_start + target_rel });
+                    // Mandatory structured diagnostic for InvalidJumpTarget
+                    let pc_abs = func_start + pc;
+                    let opcode = instr.opcode;
+                    let imm_raw = instr.imm_u32().unwrap();
+                    let func_start_abs = func_start;
+                    let func_end_abs_log = func_end_abs;
+                    let target_abs_expected = func_start_abs + target_rel;
+                    let is_boundary_target_rel = valid_pc.contains(&target_rel);
+                    eprintln!(
+                        "[VERIFIER] invalid jump: pc_abs={} opcode={:?} imm_raw={} func=F{} start={} end={} len={} target_rel={} target_abs_expected={} boundary_rel={}",
+                        pc_abs,
+                        opcode,
+                        imm_raw,
+                        func_idx,
+                        func_start_abs,
+                        func_end_abs_log,
+                        func_len,
+                        target_rel,
+                        target_abs_expected,
+                        is_boundary_target_rel
+                    );
+                    return Err(VerifierError::InvalidJumpTarget { pc: pc_abs, target: target_abs_expected });
                 }
 
                 if target_rel == func_len {

files/Hard Reset.md

@@ -11,107 +11,6 @@
 * A **single canonical layout/decoder/spec** is used across compiler/linker/verifier/VM.
 * Any invalid program fails with clear diagnostics, not panics.
 
-**Estimation scale:**
-
-* **1 point** = small / straightforward
-* **3 points** = medium
-* **5 points** = large
-* Any work that feels bigger must be broken down into multiple PRs (≤ 5 points each).
-
----
-
-## Phase 1 — Single Source of Truth: Bytecode Spec + Decoder (Highest ROI)
-
-### PR-01 (3 pts) — Move OpcodeSpec to `prometeu-bytecode` and make it authoritative
-
-**Briefing**
-
-Today opcode metadata (imm sizes, stack effects, branch-ness, terminators) is duplicated and/or inconsistent across crates. This creates a perpetual maintenance nightmare.
-
-**Target**
-
-Create one authoritative opcode spec in **`prometeu-bytecode`** and delete/replace all “local” opcode knowledge.
-
-**Scope**
-
-* Create `prometeu-bytecode::opcode_spec` containing:
-
-    * `imm_bytes`
-    * `pops`, `pushes` (stack effect)
-    * `is_branch`, `is_terminator`
-    * optional: `name`, `category`
-* Update callers to import from `prometeu-bytecode`.
-
-**Requirements Checklist**
-
-* [ ] There is exactly one canonical `OpcodeSpec` source.
-* [ ] All crates compile against that source.
-* [ ] No hardcoded operand sizes remain outside the spec.
-
-**Completion Tests**
-
-* [ ] Unit test enumerating all opcodes validates:
-
-    * every opcode has a spec
-    * `imm_bytes` is defined
-
----
-
-### PR-02 (5 pts) — Introduce canonical decoder in `prometeu-bytecode` and migrate VM to it
-
-**Briefing**
-
-The VM currently has its own decoder. The linker and other tools decode manually. This must be centralized.
-
-**Target**
-
-Add a single canonical decoder in `prometeu-bytecode` that produces typed decoded instructions.
-
-**Scope**
-
-* Add `prometeu-bytecode::decoder`:
-
-    * `decode_next(pc, bytes) -> DecodedInstr`
-    * includes: opcode, pc, next_pc, raw immediate bytes slice
-    * helpers: `imm_u8/u16/u32/i32/i64/f64` with size validation
-* Migrate VM to use `prometeu-bytecode::decoder`.
-
-**Requirements Checklist**
-
-* [ ] VM no longer has a bespoke decoder.
-* [ ] No slicing-based immediate parsing in VM core paths.
-* [ ] Decoder validates immediate sizes and fails deterministically.
-
-**Completion Tests**
-
-* [ ] Decoder unit tests for representative opcodes with each immediate size.
-* [ ] Roundtrip test: encode→decode (table-driven; property test optional).
-
----
-
-### PR-03 (3 pts) — Delete/neutralize `abi::operand_size` duplication
-
-**Briefing**
-
-`prometeu-bytecode/src/abi.rs` provides partial operand sizing that can drift from the canonical spec.
-
-**Target**
-
-Make all operand sizing derived from the opcode spec.
-
-**Scope**
-
-* Replace `operand_size()` with `OpcodeSpec::imm_bytes`.
-* Remove or restrict legacy APIs that leak duplication.
-
-**Requirements Checklist**
-
-* [ ] There is no second operand-size table.
-
-**Completion Tests**
-
-* [ ] Test ensuring `operand_size()` (if retained) matches spec for all opcodes.
-
 ---
 
 ## Phase 2 — Canonical Layout + Verifier Contract (JVM-like Control Flow)