## Problem
Exit PHI generation was using header_id as predecessor, but when
build_expression(condition) creates new blocks, the actual branch
instruction is emitted from a different block, causing:
"phi pred mismatch: no input for predecessor BasicBlockId(X)"
## Solution
- Modified build_exit_phis() to accept branch_source_block parameter
- Capture actual block after condition evaluation in loop_builder.rs
- Use branch_source_block instead of header_id for PHI inputs
## Progress
- Error changed from ValueId(5941)/BasicBlockId(4674) to
ValueId(5927)/BasicBlockId(4672), showing partial fix
- Added comprehensive test suite in mir_loopform_exit_phi.rs
- Added debug logging to trace condition block creation
## Status
Partial fix - unit tests pass, but Test 2 (Stage-B compilation) still
has errors. Needs further investigation of complex nested compilation
scenarios.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
Fixes test compilation errors caused by adding callee: Option<Callee> field
to MirInstruction::Call in previous commits.
Changes:
- tests/mir_instruction_unit.rs:
- Add callee: None to all Call instruction constructions
- Ensures backward compatibility with existing tests
- src/mir/instruction/tests.rs:
- Add callee: None to Call instruction in phi_merge_if test
- Maintains test correctness after Call signature change
- src/mir/value_id.rs:
- Add ValueId::INVALID constant (u32::MAX)
- Provides clear sentinel value for invalid/placeholder IDs
- src/mir/phi_core/loopform_builder.rs:
- Replace deprecated ValueId::from() with ValueId::new()
- Replace deprecated BasicBlockId::from() with BasicBlockId::new()
- Ensures consistency with updated ID construction patterns
Test Status:
- Original errors from our commit: 6 → 0 ✅
- Remaining errors: 45 (pre-existing, unrelated to our changes)
- 14: Missing interpreter module (legacy)
- 11: Missing VM in backend::vm (moved)
- 7: Missing jit module (archived)
- 5: Missing MirInterpreter methods (legacy)
- 4: Missing Box operator methods (pre-existing)
All test errors related to LocalSSA and Call instruction changes are resolved.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
**Problem**: is_parameter() was too simple, checking only ValueId which changes
through copies/PHIs. This caused parameters like 'data' to be misclassified as
carriers, leading to incorrect PHI construction.
**Solution**: Track original parameter names at function entry.
**Changes**:
1. **Added function_param_names field** (builder.rs):
- HashSet<String> to track original parameter names
- Populated in lower_static_method_as_function()
- Cleared and repopulated for each new function
2. **Improved is_parameter()** (loop_builder.rs):
- Check name against function_param_names instead of ValueId
- More reliable than checking func.params (ValueIds change)
- __pin$*$@* variables correctly classified as carriers
- Added debug logging with NYASH_LOOPFORM_DEBUG
3. **Enhanced debug output** (loopform_builder.rs):
- Show carrier/pinned classification during prepare_structure()
- Show variable_map state after emit_header_phis()
**Test Results**:
- ✅ 'args' correctly identified as parameter (was working)
- ✅ 'data' now correctly identified as parameter (was broken)
- ✅ __pin variables correctly classified as carriers
- ✅ PHI values allocated and variable_map updated correctly
- ⚠️ ValueId undefined errors persist (separate issue)
**Remaining Issue**:
ValueId(10) undefined error suggests PHI visibility problem or VM verification
issue. Needs further investigation of emit_phi_at_block_start() or VM executor.
**Backward Compatibility**:
- Flag OFF: 100% existing behavior preserved (legacy path unchanged)
- Feature-flagged with NYASH_LOOPFORM_PHI_V2=1
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
**Problem**: "use of undefined value ValueId(22)" errors in Stage-B
when method receivers were used after loops.
**Root cause**: prepare_loop_variables_with() explicitly skipped
pinned variables (like __pin$6438$@recv) when creating loop header
PHIs. Comment claimed they were "materialized via entry-phi in loop
body" but this only happened for the body block, not for loop exit
merge points. When receivers were used after loops, there was no PHI
to merge values from different control flow paths.
**Fix**: Remove the skip logic (lines 174-177) so pinned variables
get PHIs at loop headers and exits like any other variable.
**Impact**:
- ValueId(22) error eliminated in Stage-B selfhost tests
- MIR verification passes with NYASH_VM_VERIFY_MIR=1
- Pinned slots now correctly merge across loop boundaries
- No more "use of undefined value" for cross-loop receivers
**Test case**: /tmp/test_loop_recv.hako demonstrates receiver usage
in loop and after loop exit, now works correctly.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
- SSOT using profiles (aliases/packages via nyash.toml), AST prelude merge
- Parser/member guards; Builder pin/PHI and instance→function rewrite (dev on)
- VM refactors (handlers split) and JSON roundtrip/nested stabilization
- CURRENT_TASK.md updated with scope and acceptance criteria
Notes: dev-only guards remain togglable via env; no default behavior changes for prod.
