diff options
| -rw-r--r-- | test/ruby/test_backtrace.rb | 16 | ||||
| -rw-r--r-- | vm_backtrace.c | 52 |
2 files changed, 66 insertions, 2 deletions
diff --git a/test/ruby/test_backtrace.rb b/test/ruby/test_backtrace.rb index aa04cf0961..742463a04d 100644 --- a/test/ruby/test_backtrace.rb +++ b/test/ruby/test_backtrace.rb @@ -154,6 +154,22 @@ class TestBacktrace < Test::Unit::TestCase assert_equal caller(0), caller(0, nil) end + def test_caller_locations_first_label + def self.label + caller_locations.first.label + end + + def self.label_caller + label + end + + assert_equal 'label_caller', label_caller + + [1].group_by do + assert_equal 'label_caller', label_caller + end + end + def test_caller_locations cs = caller(0); locs = caller_locations(0).map{|loc| loc.to_s diff --git a/vm_backtrace.c b/vm_backtrace.c index 16a9cfdb33..237b010408 100644 --- a/vm_backtrace.c +++ b/vm_backtrace.c @@ -543,6 +543,11 @@ backtrace_each(const rb_execution_context_t *ec, real_size = size = last = 0; } else { + /* Ensure we don't look at frames beyond the ones requested */ + for(; from_last > 0 && start_cfp >= last_cfp; from_last--) { + last_cfp = RUBY_VM_PREVIOUS_CONTROL_FRAME(last_cfp); + } + real_size = size = start_cfp - last_cfp + 1; if (from_last > size) { @@ -568,9 +573,52 @@ backtrace_each(const rb_execution_context_t *ec, init(arg, size); - /* SDR(); */ + /* If a limited number of frames is requested, scan the VM stack for + * ignored frames (iseq without pc). Then adjust the start for the + * backtrace to account for skipped frames. + */ + if (start > 0 && num_frames >= 0 && num_frames < real_size) { + ptrdiff_t ignored_frames; + bool ignored_frames_before_start = false; + for (i=0, j=0, cfp = start_cfp; i<last && j<real_size; i++, j++, cfp = RUBY_VM_NEXT_CONTROL_FRAME(cfp)) { + if (cfp->iseq && !cfp->pc) { + if (j < start) + ignored_frames_before_start = true; + else + i--; + } + } + ignored_frames = j - i; + + if (ignored_frames) { + if (ignored_frames_before_start) { + /* There were ignored frames before start. So just decrementing + * start for ignored frames could still result in not all desired + * frames being captured. + * + * First, scan to the CFP of the desired start frame. + * + * Then scan backwards to previous frames, skipping the number of + * frames ignored after start and any additional ones before start, + * so the number of desired frames will be correctly captured. + */ + for (i=0, j=0, cfp = start_cfp; i<last && j<real_size && j < start; i++, j++, cfp = RUBY_VM_NEXT_CONTROL_FRAME(cfp)) { + /* nothing */ + } + for (; start > 0 && ignored_frames > 0 && j > 0; j--, ignored_frames--, start--, cfp = RUBY_VM_PREVIOUS_CONTROL_FRAME(cfp)) { + if (cfp->iseq && !cfp->pc) { + ignored_frames++; + } + } + } else { + /* No ignored frames before start frame, just decrement start */ + start -= ignored_frames; + } + } + } + for (i=0, j=0, cfp = start_cfp; i<last && j<real_size; i++, j++, cfp = RUBY_VM_NEXT_CONTROL_FRAME(cfp)) { - if (i < start) { + if (j < start) { if (iter_skip) { iter_skip(arg, cfp); } |