RFR: 8316702: Only evaluate buffer when IGVPrintLevelOption >= 5

[Xin Liu]

On Fri, 22 Sep 2023 01:53:24 GMT, Xin Liu <xliu at openjdk.org> wrote:

> This is a follow-up of JDK-8310220. hotspot C2 only emits IR per bytecode to IGV when level = 5. 
> 
> Currently, we conservatively check C->should_print_igv(1) in Parse::do_one_bytecode(). It's wasteful when level>1 and <= 4. We evaluate `jio_snprintf(buffer, sizeof(buffer), "Bytecode %d: %s", bci(), Bytecodes::name(bc()))` for each bytecode but emit nothing.
> 
> We should use the same level(5) in those 2 places.

tThanks for reviewing this.

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PR Comment: https://git.openjdk.org/jdk/pull/15878#issuecomment-1731031277