azalea/kotlin-fork
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

FIR CFA: properly visit subgraphs in checkers

Browse Source 
Interpretation: a graph A is a subgraph of B if information available at
nodes of A depends on the paths taken in B. For example, local classes
are subgraphs of a graph in which they are declared, and members of
those classes are subgraphs of the local class itself - because these
members can reference captured values.

Consequences:

 * if graph G is a subgraph of node N, then G is a subgraph of N's
   owner;
 * `ControlFlowAnalysisDiagnosticComponent` will only visit root graphs;
 * `graph.traverse` will ignore subgraph boundaries, as if all subgraphs
   are inlined into one huge root graph;
 * if a control flow checker needs information from a declaration to
   which a graph is attached, it must look at subgraphs explicitly.

For example, consider the `callsInPlace` checker. When a function
has a `callsInPlace` contract and a local declaration, the checker must
visit that local declaration to ensure it does not capture the allegedly
called-in-place argument - hence `graph.traverse` will look at the
nodes. However, the local declaration can also be a function with its
own `callsInPlace` contracts, so the checker should also run for it in
isolation. If that sounds quadratic, that's because unfortunately it is.
This commit is contained in:
pyos
2022-12-09 12:32:46 +01:00
committed by Dmitriy Novozhilov
parent 5180e1f4a4
commit aadea0e26f
35 changed files with 1191 additions and 1325 deletions
Download Patch File Download Diff File Expand all files Collapse all files
compiler/fir/analysis-tests/testData/resolve/smartcasts/boundSmartcasts/boundSmartcasts.dot
Vendored
+9 -10
View File
@@ -344,25 +344,24 @@ digraph boundSmartcasts_kt {
126 -> {127};
subgraph cluster_28 {
color=red
128 [label="Enter property" style="filled" fillcolor=red];
129 [label="Access variable R|<local>/any|"];
130 [label="Exit property" style="filled" fillcolor=red];
}
128 -> {129};
129 -> {130};
130 -> {133} [color=green];
subgraph cluster_29 {
color=red
131 [label="Enter class D" style="filled" fillcolor=red];
132 [label="Part of class initialization"];
subgraph cluster_29 {
color=blue
128 [label="Enter property" style="filled" fillcolor=red];
129 [label="Access variable R|<local>/any|"];
130 [label="Exit property" style="filled" fillcolor=red];
}
133 [label="Exit class D" style="filled" fillcolor=red];
}
131 -> {132} [color=green];
132 -> {128} [color=green];
132 -> {133} [style=dotted];
132 -> {128} [style=dashed];
128 -> {129};
129 -> {130};
130 -> {133} [color=green];
subgraph cluster_30 {
color=red