RFR: 8316309: AArch64: VMError::print_native_stack() crashes on Java native method frame [v2]

[Patricio Chilano Mateo]

> Please review the following patch. As explained in the bug comments the problem is that os::get_sender_for_C_frame() always constructs a frame as if the sender is also a native C/C++ frame. Setting a correct value for _unextended_sp is important to avoid crashes if this value is later used to get that frame's caller, which will happen if we end up calling frame::sender_for_compiled_frame().
> 
> The issue exists on aarch64 for both linux and macos but the fix for linux is different. The "Procedure Call Standard for the Arm 64-bit Architecture" doesn't specify a location for the frame record within a stack frame (6.4.6), and gcc happens to choose to save it the top of the frame (lowest address) rather than the bottom. This means that changing fr->link() for fr->sender_sp() won't work. The fix is to use the value of fr->link() but adjusted using the code blob frame size before setting it as the _unextended_sp of the sender frame. While working on this fix I realized the issue is not only when the sender is a native nmethod but with all frames associated with a CodeBlob with a frame size > 0 (runtime stub, safepoint stub, etc) so the check takes that into account. I also made a small fix to next_frame() since these mentioned frames should also use frame::sender().
> 
> I created a new test to verify that walking the stack over a native nmethod or runtime stub now works okay. I'll try to add a reliable test case for walking over a safepoint stub too. I tested the fix by running the new test and also running tiers1-4 in mach5. I'll run the upper tiers too.
> 
> Thanks,
> Patricio

Patricio Chilano Mateo has updated the pull request incrementally with two additional commits since the last revision:

 - add comment to tests
 - use driver + @requires vm.flagless

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/15972/files
  - new: https://git.openjdk.org/jdk/pull/15972/files/eceeed15..8757025e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=15972&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=15972&range=00-01

  Stats: 6 lines in 1 file changed: 5 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/15972.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15972/head:pull/15972

PR: https://git.openjdk.org/jdk/pull/15972