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 Change-Id: I355ac81e6ac098edc7e3cc8c13dbfa24a2969ab2
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