test: canonicalize dk_version constant for cross-arch stability

SonicField · SonicField · commit d81e5806c33f · 2026-04-21T15:56:05.000-07:00
ARM64 gate at 7a0c041 failed with diff: - v61:CUInt32[37] = LoadConst<CUInt32[37]> (x86_64) + v61:CUInt32[46] = LoadConst<CUInt32[46]> (ARM64) The CUInt32[N] constant is the `sys` module dict's `dk_version` — a monotonic counter bumped on every dict-key mutation. The value depends on how many key mutations happened during interpreter startup, which is architecture- and import-order dependent (x86_64 saw 37, ARM64 saw 46). Add a regex that canonicalizes `CUInt32[N]` (the only specialized type that can carry runtime dict-version state in the LoadAttr HIR). CUInt64[N] (slot count) and CInt64[N] (key hash / index) encode stable shape information from the class definition and are NOT canonicalized — divergence in those values is a real regression signal. Regenerated docs/golden/loadattr_hir.txt with the updated rule. Verified test PASSES on x86_64 at HEAD (run + verify cycle). ARM64 verification pending re-gate.
diff --git a/Lib/test/test_phoenix_jit_loadattr_golden.py b/Lib/test/test_phoenix_jit_loadattr_golden.py
@@ -135,9 +135,22 @@ def main():
 # stays stable.
 _PTR_RE = re.compile(r"0x[0-9a-fA-F]{6,}")
 
+# LOAD_ATTR_MODULE embeds the module dict's `dk_version` (a monotonic
+# counter bumped on every dict-key mutation) into the HIR as
+# `LoadConst<CUInt32[N]>`. N depends on how many dict mutations happened
+# during interpreter startup, which is architecture- and import-order
+# dependent (x86_64 saw 37, ARM64 saw 46). Canonicalize the embedded
+# integer on `CUInt32[N]` annotations so the golden stays cross-arch
+# stable. Other integer-specialized constant types (CUInt64[N], CInt64[N])
+# encode stable shape information (slot index, key hash) and are NOT
+# canonicalized — divergence in those values is a real regression signal.
+_DK_VERSION_RE = re.compile(r"CUInt32\[\d+\]")
+
 
 def _canonicalize(text: str) -> str:
-    return _PTR_RE.sub("0xPTR", text)
+    text = _PTR_RE.sub("0xPTR", text)
+    text = _DK_VERSION_RE.sub("CUInt32[N]", text)
+    return text
 
 
 def _extract_blocks(stderr_text: str) -> str:
diff --git a/docs/golden/loadattr_hir.txt b/docs/golden/loadattr_hir.txt
@@ -78,7 +78,7 @@ fun __main__:attr_probe {
     v59:CPtr = LoadField<ma_keys@32, CPtr, owned> v58
     Decref v58
     v60:CUInt32 = LoadField<dk_version@12, CUInt32, owned> v59
-    v61:CUInt32[37] = LoadConst<CUInt32[37]>
+    v61:CUInt32[N] = LoadConst<CUInt32[N]>
     v62:CBool = PrimitiveCompare<Equal> v60 v61
     Guard v62 {
       LiveValues<7> b:v29 b:v30 unc:v32 o:v42 o:v53 b:v56 bool:v62
@@ -222,7 +222,7 @@ fun __main__:attr_probe {
     v59:CPtr = LoadField<ma_keys@32, CPtr, owned> v58
     Decref v58
     v60:CUInt32 = LoadField<dk_version@12, CUInt32, owned> v59
-    v61:CUInt32[37] = LoadConst<CUInt32[37]>
+    v61:CUInt32[N] = LoadConst<CUInt32[N]>
     v62:CBool = PrimitiveCompare<Equal> v60 v61
     Guard v62 {
       LiveValues<7> b:v29 b:v30 unc:v32 o:v42 o:v53 b:v56 bool:v62
