RFR: 8274986: max code printed in hs-err logs should be configurable

[Tom Rodriguez]

On Fri, 8 Oct 2021 22:28:53 GMT, Doug Simon <dnsimon at openjdk.org> wrote:

> This PR adds a `ErrorLogPrintCodeLimit` (develop) option for configuring the amount of code printed in a hs-err log file. There's a hard limit of 10 so that the buffer used to avoid duplicates in `VMError::print_code` is stack allocated.
> In addition, the Java stack is also scanned when considering code to print as the native stack may not have any Java compiled frames. For example, a transition into the VM through a RuntimeStub can prevent the native stack walk from seeing the frames above the stub.
> The MachCodeFramesInErrorFile test has been made more robust in terms of validating its expectations of how C2 intrinsifies methods.
> 
> There's one other minor change to address [this comment](https://github.com/openjdk/jdk/pull/5446#issuecomment-938518814).

src/hotspot/share/code/codeBlob.cpp line 658:

> 656:     if (st == tty) {
> 657:       nm->print_nmethod(verbose);
> 658:     }

I think this should be something like this:

     ResourceMark rm;
     st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
               p2i(addr), (int)(addr - nm->entry_point()), p2i(nm));
-    if (verbose) {
-      st->print(" for ");
-      nm->method()->print_value_on(st);
-    }
     st->cr();
-    nm->print_nmethod(verbose);
+    if (verbose && st == tty) {
+      nm->print_nmethod(verbose);
+    } else {
+      nm->print_on(st);
+    }
     return;
   }
   st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", p2i(addr), (int)(addr - code_begin()));

src/hotspot/share/runtime/globals.hpp line 1339:

> 1337:           "number of stack frames to print in VM-level stack dump")         \
> 1338:                                                                             \
> 1339:   develop(int, ErrorLogPrintCodeLimit, 3,                                   \

Shouldn't this be at least diagnostic?  develop flags are fairly useless.

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PR: https://git.openjdk.java.net/jdk/pull/5875