Java: Deprecate PrimitiveType.getADefaultValue()
#6796
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| or | ||
| // The default value for primitive types. | ||
| init = t.(PrimitiveType).getADefaultValue() | ||
| isDefaultValueLiteral(init, t) |
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This looks dodgy from a performance point-of-view. Not as much the code change, but rather, this already looked dodgy before the change. So since it probably worked then it's likely that this depends on decent magic, and the changed code will still depend on magic, but since this isn't a certainty, we should verify this before merging (or update the code to not be so full of cartesian products).
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I'm ok with merging if we can verify that the optimiser pushes relevant magic into both predicates to eliminate the CPs.
| @@ -27,13 +27,24 @@ predicate flowStep(Expr decl, Expr init) { | |||
| decl.(CastExpr).getExpr() = init | |||
| } | |||
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| predicate isDefaultValueLiteral(Literal l, Type t) { | |||
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To resolve the cartesian product worry (all reftypes X all nulls), how about just omitting the Type column? This could be just:
Don't flag Expr e if e is (a) null, (b) zero, or (c) of integral type and negative one. Note this actually expands the query slightly to permit Integer i = 0;, but considering we already permit Integer i = -1; then we should probably accept that anyhow.
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Sorry for the latest response. Was this a suggestion for me or directed to aschackmull, or both of us?
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Both. @aschackmull do you think that's a sensible solution?
Resolves #6615
See #6615 (comment)