diff options
| -rw-r--r-- | src/passes/SafeHeap.cpp | 34 | ||||
| -rw-r--r-- | test/passes/safe-heap_disable-simd.txt | 7 | ||||
| -rw-r--r-- | test/passes/safe-heap_disable-simd.wast | 3 |
3 files changed, 27 insertions, 17 deletions
diff --git a/src/passes/SafeHeap.cpp b/src/passes/SafeHeap.cpp index a9ad62820..108739d66 100644 --- a/src/passes/SafeHeap.cpp +++ b/src/passes/SafeHeap.cpp @@ -32,8 +32,7 @@ namespace wasm { static const Name DYNAMICTOP_PTR_IMPORT("DYNAMICTOP_PTR"); -static const Name GET_SBRK_PTR_IMPORT("emscripten_get_sbrk_ptr"); -static const Name GET_SBRK_PTR_EXPORT("_emscripten_get_sbrk_ptr"); +static const Name GET_SBRK_PTR("emscripten_get_sbrk_ptr"); static const Name SBRK("sbrk"); static const Name SEGFAULT_IMPORT("segfault"); static const Name ALIGNFAULT_IMPORT("alignfault"); @@ -66,12 +65,21 @@ static Name getStoreName(Store* curr) { } struct AccessInstrumenter : public WalkerPass<PostWalker<AccessInstrumenter>> { + // If the getSbrkPtr function is implemented in the wasm, we must not + // instrument that, as it would lead to infinite recursion of it calling + // SAFE_HEAP_LOAD that calls it and so forth. + Name getSbrkPtr; + bool isFunctionParallel() override { return true; } - AccessInstrumenter* create() override { return new AccessInstrumenter; } + AccessInstrumenter* create() override { + return new AccessInstrumenter(getSbrkPtr); + } + + AccessInstrumenter(Name getSbrkPtr) : getSbrkPtr(getSbrkPtr) {} void visitLoad(Load* curr) { - if (curr->type == Type::unreachable) { + if (getFunction()->name == getSbrkPtr || curr->type == Type::unreachable) { return; } Builder builder(*getModule()); @@ -85,7 +93,7 @@ struct AccessInstrumenter : public WalkerPass<PostWalker<AccessInstrumenter>> { } void visitStore(Store* curr) { - if (curr->type == Type::unreachable) { + if (getFunction()->name == getSbrkPtr || curr->type == Type::unreachable) { return; } Builder builder(*getModule()); @@ -108,7 +116,7 @@ struct SafeHeap : public Pass { // add imports addImports(module); // instrument loads and stores - AccessInstrumenter().run(runner, module); + AccessInstrumenter(getSbrkPtr).run(runner, module); // add helper checking funcs and imports addGlobals(module, module->features); } @@ -118,24 +126,20 @@ struct SafeHeap : public Pass { void addImports(Module* module) { ImportInfo info(*module); // Older emscripten imports env.DYNAMICTOP_PTR. - // Newer emscripten imports emscripten_get_sbrk_ptr(), which is later - // optimized to have the number in the binary (or in the case of fastcomp, - // emscripten_get_sbrk_ptr is an asm.js library function so it is inside - // the wasm, and discoverable via an export). + // Newer emscripten imports or exports emscripten_get_sbrk_ptr(). if (auto* existing = info.getImportedGlobal(ENV, DYNAMICTOP_PTR_IMPORT)) { dynamicTopPtr = existing->name; - } else if (auto* existing = - info.getImportedFunction(ENV, GET_SBRK_PTR_IMPORT)) { + } else if (auto* existing = info.getImportedFunction(ENV, GET_SBRK_PTR)) { getSbrkPtr = existing->name; - } else if (auto* existing = module->getExportOrNull(GET_SBRK_PTR_EXPORT)) { + } else if (auto* existing = module->getExportOrNull(GET_SBRK_PTR)) { getSbrkPtr = existing->value; } else if (auto* existing = info.getImportedFunction(ENV, SBRK)) { sbrk = existing->name; } else { auto* import = new Function; - import->name = getSbrkPtr = GET_SBRK_PTR_IMPORT; + import->name = getSbrkPtr = GET_SBRK_PTR; import->module = ENV; - import->base = GET_SBRK_PTR_IMPORT; + import->base = GET_SBRK_PTR; import->sig = Signature(Type::none, Type::i32); module->addFunction(import); } diff --git a/test/passes/safe-heap_disable-simd.txt b/test/passes/safe-heap_disable-simd.txt index a0be9169f..89c8c9c3a 100644 --- a/test/passes/safe-heap_disable-simd.txt +++ b/test/passes/safe-heap_disable-simd.txt @@ -5750,8 +5750,13 @@ (import "env" "segfault" (func $segfault)) (import "env" "alignfault" (func $alignfault)) (memory $0 1 1) - (export "_emscripten_get_sbrk_ptr" (func $foo)) + (export "emscripten_get_sbrk_ptr" (func $foo)) (func $foo (result i32) + (drop + (i32.load + (i32.const 0) + ) + ) (i32.const 1234) ) (func $SAFE_HEAP_LOAD_i32_1_1 (param $0 i32) (param $1 i32) (result i32) diff --git a/test/passes/safe-heap_disable-simd.wast b/test/passes/safe-heap_disable-simd.wast index 1e15da0d1..bac91ed98 100644 --- a/test/passes/safe-heap_disable-simd.wast +++ b/test/passes/safe-heap_disable-simd.wast @@ -11,8 +11,9 @@ ) (module (memory 1 1) - (export "_emscripten_get_sbrk_ptr" (func $foo)) + (export "emscripten_get_sbrk_ptr" (func $foo)) (func $foo (result i32) + (drop (i32.load (i32.const 0))) ;; should not be modified! (i32.const 1234) ) ) |