diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/tools/fuzzing/fuzzing.cpp | 40 |
1 files changed, 21 insertions, 19 deletions
diff --git a/src/tools/fuzzing/fuzzing.cpp b/src/tools/fuzzing/fuzzing.cpp index 89ff1b459..7807ef768 100644 --- a/src/tools/fuzzing/fuzzing.cpp +++ b/src/tools/fuzzing/fuzzing.cpp @@ -313,10 +313,12 @@ void TranslateToFuzzReader::setupGlobals() { global->module = global->base = Name(); global->init = makeConst(global->type); } else { - // If the initialization referred to an imported global, it no longer - // can point to the same global after we make it a non-imported global - // (as wasm doesn't allow that - you can only use an imported one). - if (global->init->is<GlobalGet>()) { + // If the initialization referred to an imported global, it no longer can + // point to the same global after we make it a non-imported global unless + // GC is enabled, since before GC, Wasm only made imported globals + // available in constant expressions. + if (!wasm.features.hasGC() && + !FindAll<GlobalGet>(global->init).list.empty()) { global->init = makeConst(global->type); } } @@ -353,21 +355,21 @@ void TranslateToFuzzReader::finalizeMemory() { for (auto& segment : wasm.dataSegments) { Address maxOffset = segment->data.size(); if (!segment->isPassive) { - if (auto* offset = segment->offset->dynCast<GlobalGet>()) { - // Using a non-imported global in a segment offset is not valid in - // wasm. This can occur due to us making what used to be an imported - // global, in initial contents, be not imported any more. To fix that, - // replace such invalid things with a constant. - // Note that it is still possible in theory to have imported globals - // here, as we only do the above for initial contents. While the - // fuzzer doesn't do so as of the time of this comment, do a check - // for full generality, so that this code essentially does "if this - // is invalid wasm, fix it up." - if (!wasm.getGlobal(offset->name)->imported()) { - // TODO: It would be better to avoid segment overlap so that - // MemoryPacking can run. - segment->offset = - builder.makeConst(Literal::makeFromInt32(0, Type::i32)); + if (!wasm.features.hasGC()) { + // Using a non-imported global in a segment offset is not valid in wasm + // unless GC is enabled. This can occur due to us adding a local + // definition to what used to be an imported global in initial contents. + // To fix that, replace such invalid offsets with a constant. + for (auto* get : FindAll<GlobalGet>(segment->offset).list) { + // N.B: We never currently encounter imported globals here, but we do + // the check for robustness. + if (!wasm.getGlobal(get->name)->imported()) { + // TODO: It would be better to avoid segment overlap so that + // MemoryPacking can run. + segment->offset = + builder.makeConst(Literal::makeFromInt32(0, Type::i32)); + break; + } } } if (auto* offset = segment->offset->dynCast<Const>()) { |