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11c71fdd18
This commit removes SSA nodes from the data flow graph. Specifically, for a definition and use such as ```python x = expr y = x + 2 ``` we used to have flow from `expr` to an SSA variable representing x and from that SSA variable to the use of `x` in the definition of `y`. Now we instead have flow from `expr` to the control flow node for `x` at line 1 and from there to the control flow node for `x` at line 2. Specific changes: - `EssaNode` from the data flow layer no longer exists. - Several glue steps between `EssaNode`s and `CfgNode`s have been deleted. - Entry nodes are now admitted as `CfgNodes` in the data flow layer (they were filtered out before). - Entry nodes now have a new `toString` taking into account that the module name may be ambigous. - Some tests have been rewritten to accomodate the changes, but only `python/ql/test/experimental/dataflow/basic/maximalFlowsConfig.qll` should have semantic changes. - Comments have been updated - Test output has been updated, but apart from `python/ql/test/experimental/dataflow/basic/maximalFlows.expected` only `python/ql/test/experimental/dataflow/typetracking-summaries/summaries.py` should have a semantic change. This is a bonus fix, probably meaning that something was never connected up correctly.
8 lines
415 B
Python
8 lines
415 B
Python
def obfuscated_id(x): #$ step="FunctionExpr -> obfuscated_id"
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y = x #$ step="x -> y" step="x, l:-1 -> x"
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z = y #$ step="y -> z" step="y, l:-1 -> y"
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return z #$ flow="42, l:+2 -> z" step="z, l:-1 -> z"
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a = 42 #$ step="42 -> a"
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b = obfuscated_id(a) #$ flow="42, l:-1 -> b" flow="FunctionExpr, l:-6 -> obfuscated_id" step="obfuscated_id(..) -> b" step="obfuscated_id, l:-6 -> obfuscated_id" step="a, l:-1 -> a"
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