tree 901a4e48313d497b784f5fca3f88b0405d6a8dec
parent 92fbd284fa595724c47d1a803b50c3891b9836b3
author Sebastien Hertz <shertz@google.com> 1421434149 +0100
committer Sebastien Hertz <shertz@google.com> 1422032439 +0100

Fix exception handling during deoptimization

When interpreting a deoptimized shadow frame, we may start with a
pending exception thrown by a previous deoptimized shadow frame (from
a previous invoke). Therefore, we need to handle it before executing
any instruction, otherwise we execute incorrect code.

Because we need the DEX pc of the throwing instruction to find a
matching catch handler, we initialize deoptimized shadow frames with
the current DEX pc at the time the stack is deoptimized.
When we are about to interpret a deoptimized shadow frame, we need to
update the shadow frame with the DEX pc of the next instruction to
interpret. There are three cases:
- if there is no pending exception, this is the instruction following
the current one.
- if there is a pending exception and we found a matching catch
handler, this is the first instruction of this handler.
- if there is a pending exception but there is no matching catch
handler, we do not execute the deoptimized shadow frame and continue
to its caller.

The verifier now fails when a method starts with a move-exception
instruction. Indeed we cannot start executing a method with a pending
exception.

Bug: 19057915
Bug: 19041195
Bug: 18607595

(cherry picked from commit 270a0e16c3b8e5b95cbfdbd8996ac137c7c6322b)

Change-Id: Ib4fdd0ad704b4f2369d229737c9cc77f559cea55