ruby/tool/ruby_vm
Peter Zhu 3e09822407 Fix incorrect line numbers in GC hook
If the previous instruction is not a leaf instruction, then the PC was
incremented before the instruction was ran (meaning the currently
executing instruction is actually the previous instruction), so we
should not increment the PC otherwise we will calculate the source
line for the next instruction.

This bug can be reproduced in the following script:

```
require "objspace"

ObjectSpace.trace_object_allocations_start
a =

  1.0 / 0.0
p [ObjectSpace.allocation_sourceline(a), ObjectSpace.allocation_sourcefile(a)]
```

Which outputs: [4, "test.rb"]

This is incorrect because the object was allocated on line 10 and not
line 4. The behaviour is correct when we use a leaf instruction (e.g.
if we replaced `1.0 / 0.0` with `"hello"`), then the output is:
[10, "test.rb"].

[Bug #19456]
2023-02-24 14:10:09 -05:00
..
controllers
helpers Revert "FreeBSD make uses the target under srcdir [ci skip]" 2022-10-13 12:24:59 +09:00
loaders
models Fix RubyVM::CExpr#inspect 2023-02-24 14:10:09 -05:00
scripts
tests
views Fix incorrect line numbers in GC hook 2023-02-24 14:10:09 -05:00