8359920: Use names for frame types in stackmaps

[coleenp]

This uses names for frame types for stackmaps in the verifier and redefinition.
Tested with tier1-7.

---

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Issue

• JDK-8359920: Use names for frame types in stackmaps (Enhancement - P4)

Reviewers

• Johan Sjölen (@jdksjolen - Reviewer) Review applies to 37b5c7ee
• Matias Saavedra Silva (@matias9927 - Reviewer)
• Serguei Spitsyn (@sspitsyn - Reviewer) Review applies to 37b5c7ee

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8359920: Use names for frame types in stackmaps

Reviewed-by: matsaave, jsjolen, sspitsyn

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• 17cf497: 8357550: GenShen crashes during freeze: assert(!chunk->requires_barriers()) failed
• c6ab63d: 8359735: [Ubuntu 25.10] java/lang/ProcessBuilder/Basic.java, java/lang/ProcessHandle/InfoTest.java fail due to rust-coreutils
• ff54a64: 8360049: CodeInvalidationReasonTest.java fails with ZGC on AArch64
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Webrevs

• 03: Full - Incremental (7d2e60c2)
• 02: Full - Incremental (107382e4)
• 01: Full - Incremental (c3d8d0fc)
• 00: Full (37b5c7ee)

[matias9927]

LGTM, thanks!

[dholmes-ora]

I find these definitions a little confusing. SAME_FRAME is actually 0-63, with SAME_LOCALS_1_STACK_ITEM_FRAME being 64-127. Given many of these frame types imply tag ranges it may be clearer to define enum's for the start and end of ranges as applicable eg.

enum {
  SAME_FRAME_START = 0,
  SAME_FRAME_END = 63,
  SAME_LOCALS_1_STACK_ITEM_FRAME_START = 64,
  SAME_LOCALS_1_STACK_ITEM_FRAME_END = 127,
  RESERVED_START = 128,
  RESERVED_END = 246,
  SAME_LOCALS_1_STACK_ITEM_EXTENDED = 247,
  CHOP_FRAME_START = 248,
  CHOP_FRAME_END = 250,
  SAME_FRAME_EXTENDED = 251,
  APPEND_FRAME_START = 252,
  APPEND_FRAME_END = 254,
  FULL_FRAME = 255
}

and then adjust the code usage as appropriate e.g.

if (frame_type <= SAME_FRAME_END) {
...
if (frame_type <= SAME_LOCALS_1_STACK_ITEM_FRAME_END) {
  if (_first) {
    offset = frame_type - SAME_LOCALS_1_STACK_ITEM_FRAME_START;
...

What do you think?

[coleenp]

I wasn't really up for a big rewrite but having the complete set of names would be really good.

[sspitsyn]

This looks good.
I was also thinking about frame_type ranges but no ideas on any improvements.

[coleenp]

tiers 1-4 passed with changes suggested by @dholmes-ora

[matias9927]

Updated change looks good!