fix(hermes-base): fold UIntSwitchImm jump-table offsets in the equivalence check

The two switch instructions carry the jump-table offset in different
operands:

  StringSwitchImm rX, <id>, <jtOffset>, <defaultLabel>, <count>
  UIntSwitchImm   rX, <jtOffset>, <defaultLabel>, <min>, <max>

Only the first shape was folded. Under -pretty-disassemble the default
target of a UIntSwitchImm prints as a label (`L3`), so the existing regex
— which expects a second number where the label is — never matched, and
a jump-table offset that had simply moved with instruction widths read as
a real difference. --verifyHermesBase then dropped a perfectly good delta
build and fell back to the plain compile, silently, on exactly the bundles
where switches are common.

Found while benchmarking delta mode on the RN 0.86 example app: the
~300 LOC scenario failed on one line (5937 vs 5938) and lost the delta
build, taking its patch from 97.8 KB to 381.0 KB — 3.9x larger. With this
fix all three scenarios verify clean (566k-591k instructions compared).

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01U1e5fWU5jWwgH4ctKwYx5y

Author: sunnylqm

src/utils/hermes-base.ts

@@ -643,10 +643,17 @@ export function normalizeDisassemblyLine(
   // wider form. Fold the suffix and the column padding that follows it.
   m = /^(\s*)([A-Za-z]+?)(?:LongIndex|Long|Short)?(\s+.*|)$/.exec(line);
   if (m) line = `${m[1]}${m[2]}${m[3].replace(/\s+/g, ' ')}`;
-  // switch jump tables sit after the instructions; their relative offset (and
-  // the table header hermesc prints for them) moves with instruction widths
+  // Switch jump tables sit after the instructions; their relative offset (and
+  // the table header hermesc prints for them) moves with instruction widths.
+  // The two switch instructions carry that offset in different operands:
+  //   StringSwitchImm rX, <id>, <jtOffset>, <defaultLabel>, <count>
+  //   UIntSwitchImm   rX, <jtOffset>, <defaultLabel>, <min>, <max>
+  // Folding only the first shape let a shifted UIntSwitchImm offset read as a
+  // real difference and drop an otherwise good delta build.
   m = /^(\s*(?:String|UInt)?SwitchImm r\d+, \d+, )\d+(, .*)$/.exec(line);
   if (m) line = `${m[1]}<jt>${m[2]}`;
+  m = /^(\s*(?:String|UInt)?SwitchImm r\d+, )\d+(, L\d+, .*)$/.exec(line);
+  if (m) line = `${m[1]}<jt>${m[2]}`;
   if (/^\s*offset \d+$/.test(line)) line = line.replace(/\d+$/, '<jt>');
   return line;
 }

tests/hermes-base.test.ts

@@ -461,6 +461,19 @@ describe('helpers', () => {
         strings,
       ),
     ).toBe('    StringSwitchImm r13, 2, <jt>, L146, 150');
+    // UIntSwitchImm carries the jump-table offset one operand earlier
+    expect(
+      normalizeDisassemblyLine(
+        '    UIntSwitchImm     r40, 5937, L3, 0, 31',
+        strings,
+      ),
+    ).toBe('    UIntSwitchImm r40, <jt>, L3, 0, 31');
+    expect(
+      normalizeDisassemblyLine(
+        '    UIntSwitchImm     r40, 5938, L3, 0, 31',
+        strings,
+      ),
+    ).toBe('    UIntSwitchImm r40, <jt>, L3, 0, 31');
     expect(normalizeDisassemblyLine('  offset 4024', strings)).toBe(
       '  offset <jt>',
     );