RFR: 8281829: runtime/CommandLine/OptionsValidation/TestOptionsWithRanges.java fails after JDK-8281467 [v2]

[Jie Fu]

> Hi all,
> 
> runtime/CommandLine/OptionsValidation/TestOptionsWithRanges.java fails due to SIGFPE after JDK-8281467 with release VMs.
> It can be reproduced by running `java -XX:+UnlockExperimentalVMOptions -XX:CodeEntryAlignment=4294967296` with release VMs.
> 
> This is because `CodeEntryAlignment` would be converted from `intx` to `int` at line 825.
> 
>  824   address generate_fp_mask(const char *stub_name, int64_t mask) {
>  825     __ align(CodeEntryAlignment);
>  826     StubCodeMark mark(this, "StubRoutines", stub_name);
>  827     address start = __ pc();
>  828
>  829     __ emit_data64( mask, relocInfo::none );
>  830     __ emit_data64( mask, relocInfo::none );
>  831
>  832     return start;
>  833   }
> 
> 
> Then at line 1187, `modulus` would become 0 after the conversion of `CodeEntryAlignment`, which leads to SIGFPE at line 1191.
> 
> 1184 void MacroAssembler::align(int modulus) {
> 1185   // 8273459: Ensure alignment is possible with current segment alignment
> 1186   assert(modulus <= CodeEntryAlignment, "Alignment must be <= CodeEntryAlignment");
> 1187   align(modulus, offset());
> 1188 }
> 1189
> 1190 void MacroAssembler::align(int modulus, int target) {
> 1191   if (target % modulus != 0) {
> 1192     nop(modulus - (target % modulus));
> 1193   }
> 1194 }
> 
> 
> The fix just adding a rule (`CodeEntryAlignment <= CodeCacheSegmentSize`) in `CodeEntryAlignmentConstraintFunc`.
> 
> This is fine because we already has that rule in `CodeCacheSegmentSizeConstraintFunc`.
> And this is necessary since `CodeCacheSegmentSizeConstraintFunc` won't be called in release VMs.
> 
> Thanks.
> Best regards,
> Jie

Jie Fu has updated the pull request incrementally with one additional commit since the last revision:

  Address review comment

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/7480/files
  - new: https://git.openjdk.java.net/jdk/pull/7480/files/b39bc8f3..5c274548

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=7480&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=7480&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7480.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7480/head:pull/7480

PR: https://git.openjdk.java.net/jdk/pull/7480