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Tweak adapter cost of lists (#4853)

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I noticed an oss-fuzz-based timeout that was reported for the
`component_api` fuzzer where the adapter module generated takes 1.5
seconds to compile the singular function in release mode (no fuzzing
enabled). The test case in question was a deeply recursive
list-of-list-of-etc and only one function was generated instead of
multiple. I updated the cost of strings/lists to cost more in the
approximate cost calculation which now forces the one giant function to
get split up and the large function is now split up into multiple
smaller function that take milliseconds to compile.
This commit is contained in:
Alex Crichton
2022-09-02 13:11:48 -05:00
committed by GitHub
parent f30a7eb0c9
commit b8a68ff86d
1 changed files with 3 additions and 3 deletions
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6
crates/environ/src/fact/trampoline.rs
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@@ -514,12 +514,12 @@ impl Compiler<'_, '_> {
InterfaceType::Char => 1, InterfaceType::Char => 1,
// This has a fair bit of code behind it depending on the // This has a fair bit of code behind it depending on the
// strings/encodings in play, so arbitrarily assign it a cost a 5. // strings/encodings in play, so arbitrarily assign it this cost.
InterfaceType::String => 5, InterfaceType::String => 40,
// Iteration of a loop is along the lines of the cost of a string // Iteration of a loop is along the lines of the cost of a string
// so give it the same cost // so give it the same cost
InterfaceType::List(_) => 5, InterfaceType::List(_) => 40,
InterfaceType::Flags(i) => { InterfaceType::Flags(i) => {
let count = self.module.types[*i].names.len(); let count = self.module.types[*i].names.len();