[lworld] RFR: 8320225: [lworld] TestBasicFunctionality::test20 fails intermittently because it does not correctly handle coalescing of subword stores [v2]

[Tobias Hartmann]

> `TestBasicFunctionality::test20` fails intermittently if one of the randomly chosen field values of a value object is zero because that will lead to slightly different type information for the captured stores that initialize the object. 
> 
> Passing case:
> 
> 299  StoreP  === 330 375 285 290  [[ 302 304 ]]  @rawptr:BotPTR, idx=Raw;  Memory: @rawptr:BotPTR, idx=Raw;
> 304  StoreL  === 330 299 289 302  [[ 308 ]]  @null  Memory: @rawptr:BotPTR, idx=Raw;
> 308  StoreNKlass  === 330 304 306 331  [[ 316 ]]  @null  Memory: @rawptr:BotPTR, idx=Raw;
> 316  StoreI  === 330 308 315 57  [[ 280 ]]  @rawptr:BotPTR, idx=Raw;  Memory: @rawptr:BotPTR, idx=Raw;
> 311  StoreL  === 279 280 309 310  [[ 246 ]]  @rawptr:BotPTR, idx=Raw;  Memory: @rawptr:BotPTR, idx=Raw; !orig=[245],3161 !jvms: MyValue1::<vnew> @ bci:82 (line 57) MyValue1::setV4 @ bci:40 (line 178) MyValue1::createWithFieldsInline @ bci:106 (line 89) TestBasicFunctionality::test20 @ bci:6 (line 475)
> 246  StoreL  === 279 311 254 188  [[ 314 ]]  @compiler/valhalla/inlinetypes/MyValue2 (compiler/valhalla/inlinetypes/MyInterface):exact+24 *, name=l, idx=11;  Memory: @rawptr:BotPTR, idx=Raw; !orig=3166 !jvms: MyValue1::<vnew> @ bci:82 (line 57) MyValue1::setV4 @ bci:40 (line 178) MyValue1::createWithFieldsInline @ bci:106 (line 89) TestBasicFunctionality::test20 @ bci:6 (line 475)
> 314  StoreL  === 279 246 312 313  [[ 231 ]]  @rawptr:BotPTR, idx=Raw;  Memory: @rawptr:BotPTR, idx=Raw; !orig=[248],3178 !jvms: MyValue1::<vnew> @ bci:82 (line 57) MyValue1::setV4 @ bci:40 (line 178) MyValue1::createWithFieldsInline @ bci:106 (line 89) TestBasicFunctionality::test20 @ bci:6 (line 475)
> 
> 
> Failing case:
> 
> 300  StoreP  === 337 384 286 291  [[ 303 305 ]]  @rawptr:BotPTR, idx=Raw;  Memory: @rawptr:BotPTR, idx=Raw;
> 305  StoreL  === 337 300 290 303  [[ 309 ]]  @null  Memory: @rawptr:BotPTR, idx=Raw;
> 309  StoreNKlass  === 337 305 307 338  [[ 317 ]]  @null  Memory: @rawptr:BotPTR, idx=Raw;
> 317  StoreI  === 337 309 316 57  [[ 343 ]]  @rawptr:BotPTR, idx=Raw;  Memory: @rawptr:BotPTR, idx=Raw;
> 343  StoreL  === 337 317 322 184  [[ 281 ]]  @rawptr:BotPTR, idx=Raw;  Memory: @rawptr:BotPTR, idx=Raw; !orig=[323]
> 312  StoreL  === 280 281 310 311  [[ 315 ]]  @rawptr:BotPTR, idx=Raw;  Memory: @rawptr:BotPTR, idx=Raw; !orig=[248],3163 !jvms: MyValue1::<vnew> @ bci:82 (line 57) MyValue1::setV4 @ bci:40 (line 178) MyValue1::createWithFieldsInline @ bci:106 (line 89) TestBasicFunctionality::test20 @ bci:6 (line 475)
> 315  StoreL  === 280 312 313 314  [[ 234 ]]  @ra...

Tobias Hartmann has updated the pull request incrementally with one additional commit since the last revision:

  Removed it

-------------

Changes:
  - all: https://git.openjdk.org/valhalla/pull/957/files
  - new: https://git.openjdk.org/valhalla/pull/957/files/8a878522..5875bf01

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=valhalla&pr=957&range=01
 - incr: https://webrevs.openjdk.org/?repo=valhalla&pr=957&range=00-01

  Stats: 3 lines in 1 file changed: 0 ins; 2 del; 1 mod
  Patch: https://git.openjdk.org/valhalla/pull/957.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/957/head:pull/957

PR: https://git.openjdk.org/valhalla/pull/957