Breakpad processor: Save Windows unwinding data earlier in x86 walker.

At the moment, StackwalkerX86::GetCallerFrame doesn't save the
WindowsFrameInfo that it finds for a frame unless it successfully
constructs the caller frame. This means that the windows_frame_info
field of the last frame on the stack is left unset, even when that
frame does have windows unwinding information.

This is not user-visible behavior, so it doesn't matter, but it is a
blemish on the interface, and unit tests (added in a later patch)
expect it.

This patch saves the information in the frame as soon as we find it.

a=jimblandy, r=mmentovai


git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@508 4c0a9323-5329-0410-9bdc-e9ce6186880e
This commit is contained in:
jimblandy 2010-02-05 17:14:12 +00:00
parent e53e6af0c1
commit e87521a989

View file

@ -103,6 +103,10 @@ StackFrame* StackwalkerX86::GetCallerFrame(const CallStack *stack) {
WindowsFrameInfo *last_frame_info WindowsFrameInfo *last_frame_info
= resolver_->FindWindowsFrameInfo(last_frame); = resolver_->FindWindowsFrameInfo(last_frame);
// Save the stack walking info we found, in case we need it later to
// find the callee of the frame we're constructing now.
last_frame->windows_frame_info = last_frame_info;
// This stackwalker sets each frame's %esp to its value immediately prior // This stackwalker sets each frame's %esp to its value immediately prior
// to the CALL into the callee. This means that %esp points to the last // to the CALL into the callee. This means that %esp points to the last
// callee argument pushed onto the stack, which may not be where %esp points // callee argument pushed onto the stack, which may not be where %esp points
@ -442,9 +446,6 @@ StackFrame* StackwalkerX86::GetCallerFrame(const CallStack *stack) {
// StackFrameX86. // StackFrameX86.
frame->instruction = frame->context.eip - 1; frame->instruction = frame->context.eip - 1;
// Save the stack walking info we found for the callee.
last_frame->windows_frame_info = last_frame_info;
return frame; return frame;
} }