search

DynamoRIO / dynamorio

Dynamic Instrumentation Tool Platform
Other
2.61k stars 554 forks source link

Convert predicated execution to non-predicated execution #1555

Open derekbruening opened 9 years ago

derekbruening commented 9 years ago

From zhao...@google.com on October 24, 2014 11:27:23

Architecture like ARM supports predicated instructions, which causes many problems for current DynamoRIO tools.

For example, instr_writes_to_reg is often used for register liveness analysis and finding dead registers. However, due to the predicated execution, those registers might not be dead during the execution if the condition is false. Similar problems happen to the eflags analysis too. Also, DynamoRIO based code coverage will also have the problem, as the code brought to code cache might not be executed at all.

So one potential solution is to convert predicated instructions to non-predicated instructions guarded with conditional branch, which would makes the analysis easier.

Original issue: http://code.google.com/p/dynamorio/issues/detail?id=1555

derekbruening commented 9 years ago

From zhao...@google.com on October 24, 2014 08:29:26

Labels: OpSys-ARM

derekbruening commented 9 years ago

From bruen...@google.com on October 24, 2014 08:30:07

Xref issue #269

derekbruening commented 7 years ago

Generally we've integrated predication as a first-class feature and prefer other solutions such as #1729