diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/ir/ExpressionAnalyzer.cpp | 20 | ||||
-rw-r--r-- | src/ir/branch-utils.h | 48 | ||||
-rw-r--r-- | src/ir/properties.h | 10 | ||||
-rw-r--r-- | src/passes/Poppify.cpp | 8 | ||||
-rw-r--r-- | src/passes/Print.cpp | 77 | ||||
-rw-r--r-- | src/passes/RemoveUnusedNames.cpp | 2 | ||||
-rw-r--r-- | src/passes/StackIR.cpp | 4 | ||||
-rw-r--r-- | src/shared-constants.h | 1 | ||||
-rw-r--r-- | src/wasm-binary.h | 4 | ||||
-rw-r--r-- | src/wasm-delegations-fields.h | 2 | ||||
-rw-r--r-- | src/wasm-s-parser.h | 3 | ||||
-rw-r--r-- | src/wasm-stack.h | 15 | ||||
-rw-r--r-- | src/wasm-type.h | 1 | ||||
-rw-r--r-- | src/wasm.h | 4 | ||||
-rw-r--r-- | src/wasm/wasm-binary.cpp | 173 | ||||
-rw-r--r-- | src/wasm/wasm-s-parser.cpp | 56 | ||||
-rw-r--r-- | src/wasm/wasm-stack.cpp | 16 | ||||
-rw-r--r-- | src/wasm/wasm-validator.cpp | 68 | ||||
-rw-r--r-- | src/wasm/wasm.cpp | 1 |
19 files changed, 422 insertions, 91 deletions
diff --git a/src/ir/ExpressionAnalyzer.cpp b/src/ir/ExpressionAnalyzer.cpp index 04ef52026..0b0adae9e 100644 --- a/src/ir/ExpressionAnalyzer.cpp +++ b/src/ir/ExpressionAnalyzer.cpp @@ -17,6 +17,7 @@ #include "ir/iteration.h" #include "ir/load-utils.h" #include "ir/utils.h" +#include "shared-constants.h" #include "support/hash.h" #include "support/small_vector.h" #include "wasm-traversal.h" @@ -261,6 +262,9 @@ size_t ExpressionAnalyzer::hash(Expression* curr) { Hasher(Expression* curr) { stack.push_back(curr); + // DELEGATE_CALLER_TARGET is a fake target used to denote delegating to + // the caller. Add it here to prevent the unknown name error. + noteScopeName(DELEGATE_CALLER_TARGET); while (stack.size() > 0) { curr = stack.back(); @@ -327,13 +331,15 @@ size_t ExpressionAnalyzer::hash(Expression* curr) { } } void visitScopeName(Name curr) { - // Names are relative, we give the same hash for - // (block $x (br $x)) - // (block $y (br $y)) - static_assert(sizeof(Index) == sizeof(int32_t), - "wasm64 will need changes here"); - assert(internalNames.find(curr) != internalNames.end()); - rehash(digest, internalNames[curr]); + if (curr.is()) { // try's delegate target can be null + // Names are relative, we give the same hash for + // (block $x (br $x)) + // (block $y (br $y)) + static_assert(sizeof(Index) == sizeof(int32_t), + "wasm64 will need changes here"); + assert(internalNames.find(curr) != internalNames.end()); + rehash(digest, internalNames[curr]); + } } void visitNonScopeName(Name curr) { rehash(digest, uint64_t(curr.str)); } void visitType(Type curr) { rehash(digest, curr.getID()); } diff --git a/src/ir/branch-utils.h b/src/ir/branch-utils.h index a9561ef07..8a4f02a58 100644 --- a/src/ir/branch-utils.h +++ b/src/ir/branch-utils.h @@ -40,9 +40,9 @@ inline bool isBranchReachable(Expression* expr) { return true; } -// Perform a generic operation on uses of scope names (branch targets) in an -// expression. The provided function receives a Name& which it can modify if it -// needs to. +// Perform a generic operation on uses of scope names (branch + delegate +// targets) in an expression. The provided function receives a Name& which it +// can modify if it needs to. template<typename T> void operateOnScopeNameUses(Expression* expr, T func) { #define DELEGATE_ID expr->_id @@ -83,7 +83,7 @@ void operateOnScopeNameUsesAndSentTypes(Expression* expr, T func) { } else if (auto* br = expr->dynCast<BrOn>()) { func(name, br->getCastType()); } else { - WASM_UNREACHABLE("bad br type"); + assert(expr->is<Try>()); // delegate } }); } @@ -135,6 +135,46 @@ inline bool replacePossibleTarget(Expression* branch, Name from, Name to) { return worked; } +// Replace all delegate targets within the given AST. +inline void replaceDelegateTargets(Expression* ast, Name from, Name to) { + struct Replacer + : public PostWalker<Replacer, UnifiedExpressionVisitor<Replacer>> { + Name from, to; + Replacer(Name from, Name to) : from(from), to(to) {} + void visitExpression(Expression* curr) { + if (curr->is<Try>()) { + operateOnScopeNameUses(curr, [&](Name& name) { + if (name == from) { + name = to; + } + }); + } + } + }; + Replacer replacer(from, to); + replacer.walk(ast); +} + +// Replace all branch targets within the given AST. +inline void replaceBranchTargets(Expression* ast, Name from, Name to) { + struct Replacer + : public PostWalker<Replacer, UnifiedExpressionVisitor<Replacer>> { + Name from, to; + Replacer(Name from, Name to) : from(from), to(to) {} + void visitExpression(Expression* curr) { + if (Properties::isBranch(curr)) { + operateOnScopeNameUses(curr, [&](Name& name) { + if (name == from) { + name = to; + } + }); + } + } + }; + Replacer replacer(from, to); + replacer.walk(ast); +} + // Returns the set of targets to which we branch that are // outside of an expression. inline NameSet getExitingBranches(Expression* ast) { diff --git a/src/ir/properties.h b/src/ir/properties.h index b60c74d98..8ae7befba 100644 --- a/src/ir/properties.h +++ b/src/ir/properties.h @@ -69,13 +69,15 @@ inline bool isControlFlowStructure(Expression* curr) { curr->is<Try>(); } -// Check if an expression is a control flow construct with a name, -// which implies it may have breaks to it. +// Check if an expression is a control flow construct with a name, which implies +// it may have breaks or delegates to it. inline bool isNamedControlFlow(Expression* curr) { if (auto* block = curr->dynCast<Block>()) { return block->name.is(); } else if (auto* loop = curr->dynCast<Loop>()) { return loop->name.is(); + } else if (auto* try_ = curr->dynCast<Try>()) { + return try_->name.is(); } return false; } @@ -104,6 +106,10 @@ inline bool isConstantExpression(const Expression* curr) { return false; } +inline bool isBranch(const Expression* curr) { + return curr->is<Break>() || curr->is<Switch>() || curr->is<BrOn>(); +} + inline Literal getLiteral(const Expression* curr) { if (auto* c = curr->dynCast<Const>()) { return c->value; diff --git a/src/passes/Poppify.cpp b/src/passes/Poppify.cpp index b0d07e60c..2ab222697 100644 --- a/src/passes/Poppify.cpp +++ b/src/passes/Poppify.cpp @@ -128,6 +128,7 @@ struct Poppifier : BinaryenIRWriter<Poppifier> { void emitIfElse(If* curr); void emitCatch(Try* curr, Index i); void emitCatchAll(Try* curr); + void emitDelegate(Try* curr); void emitScopeEnd(Expression* curr); void emitFunctionEnd(); void emitUnreachable(); @@ -272,6 +273,13 @@ void Poppifier::emitCatchAll(Try* curr) { scopeStack.emplace_back(Scope::Catch); } +void Poppifier::emitDelegate(Try* curr) { + auto& scope = scopeStack.back(); + assert(scope.kind == Scope::Try); + patchScope(curr->body); + scopeStack.back().instrs.push_back(curr); +} + void Poppifier::emitScopeEnd(Expression* curr) { switch (scopeStack.back().kind) { case Scope::Block: diff --git a/src/passes/Print.cpp b/src/passes/Print.cpp index e49735af0..9b59de444 100644 --- a/src/passes/Print.cpp +++ b/src/passes/Print.cpp @@ -1764,6 +1764,10 @@ struct PrintExpressionContents void visitRefEq(RefEq* curr) { printMedium(o, "ref.eq"); } void visitTry(Try* curr) { printMedium(o, "try"); + if (curr->name.is()) { + o << ' '; + printName(curr->name, o); + } if (curr->type.isConcrete()) { o << ' ' << ResultType(curr->type); } @@ -1955,6 +1959,9 @@ struct PrintSExpression : public OverriddenVisitor<PrintSExpression> { Function::DebugLocation lastPrintedLocation; bool debugInfo; + // Used to print delegate's depth argument when it throws to the caller + int controlFlowDepth = 0; + PrintSExpression(std::ostream& o) : o(o) { setMinify(false); if (!full) { @@ -2100,6 +2107,9 @@ struct PrintSExpression : public OverriddenVisitor<PrintSExpression> { break; // that's all we can recurse, start to unwind } } + + int startControlFlowDepth = controlFlowDepth; + controlFlowDepth += stack.size(); auto* top = stack.back(); while (stack.size() > 0) { curr = stack.back(); @@ -2129,8 +2139,10 @@ struct PrintSExpression : public OverriddenVisitor<PrintSExpression> { o << ' ' << curr->name; } } + controlFlowDepth = startControlFlowDepth; } void visitIf(If* curr) { + controlFlowDepth++; o << '('; printExpressionContents(curr); incIndent(); @@ -2147,8 +2159,10 @@ struct PrintSExpression : public OverriddenVisitor<PrintSExpression> { if (full) { o << " ;; end if"; } + controlFlowDepth--; } void visitLoop(Loop* curr) { + controlFlowDepth++; o << '('; printExpressionContents(curr); incIndent(); @@ -2160,6 +2174,7 @@ struct PrintSExpression : public OverriddenVisitor<PrintSExpression> { o << ' ' << curr->name; } } + controlFlowDepth--; } void visitBreak(Break* curr) { o << '('; @@ -2490,13 +2505,28 @@ struct PrintSExpression : public OverriddenVisitor<PrintSExpression> { // (do // ... // ) - // (catch - // ... + // (catch $e + // ... + // ) + // ... + // (catch_all + // ... // ) // ) - // The parenthesis wrapping 'catch' is just a syntax and does not affect - // nested depths of instructions within. + // The parenthesis wrapping do/catch/catch_all is just a syntax and does not + // affect nested depths of instructions within. + // + // try-delegate is written in the forded format as + // (try + // (do + // ... + // ) + // (delegate $label) + // ) + // When the 'delegate' delegates to the caller, we write the argument as an + // immediate. void visitTry(Try* curr) { + controlFlowDepth++; o << '('; printExpressionContents(curr); incIndent(); @@ -2521,12 +2551,26 @@ struct PrintSExpression : public OverriddenVisitor<PrintSExpression> { if (curr->hasCatchAll()) { doIndent(o, indent); printDebugDelimiterLocation(curr, curr->catchEvents.size()); - o << "(catch_all"; + o << '('; + printMedium(o, "catch_all"); incIndent(); maybePrintImplicitBlock(curr->catchBodies.back(), true); decIndent(); o << "\n"; } + controlFlowDepth--; + + if (curr->isDelegate()) { + doIndent(o, indent); + o << '('; + printMedium(o, "delegate "); + if (curr->delegateTarget == DELEGATE_CALLER_TARGET) { + o << controlFlowDepth; + } else { + printName(curr->delegateTarget, o); + } + o << ")\n"; + } decIndent(); if (full) { o << " ;; end try"; @@ -2913,6 +2957,7 @@ struct PrintSExpression : public OverriddenVisitor<PrintSExpression> { } else { printFullLine(curr->body); } + assert(controlFlowDepth == 0); } else { // Print the stack IR. printStackIR(curr->stackIR.get(), o, curr); @@ -3324,6 +3369,11 @@ printStackInst(StackInst* inst, std::ostream& o, Function* func) { printMedium(o, "catch_all"); break; } + case StackInst::Delegate: { + printMedium(o, "delegate "); + printName(inst->origin->cast<Try>()->delegateTarget, o); + break; + } default: WASM_UNREACHABLE("unexpeted op"); } @@ -3339,6 +3389,7 @@ printStackIR(StackIR* ir, std::ostream& o, Function* func) { } }; + int controlFlowDepth = 0; // Stack to track indices of catches within a try SmallVector<Index, 4> catchIndexStack; for (Index i = 0; i < (*ir).size(); i++) { @@ -3364,6 +3415,7 @@ printStackIR(StackIR* ir, std::ostream& o, Function* func) { case StackInst::BlockBegin: case StackInst::IfBegin: case StackInst::LoopBegin: { + controlFlowDepth++; doIndent(); PrintExpressionContents(func, o).visit(inst->origin); indent++; @@ -3375,6 +3427,7 @@ printStackIR(StackIR* ir, std::ostream& o, Function* func) { case StackInst::BlockEnd: case StackInst::IfEnd: case StackInst::LoopEnd: { + controlFlowDepth--; indent--; doIndent(); printMedium(o, "end"); @@ -3403,11 +3456,25 @@ printStackIR(StackIR* ir, std::ostream& o, Function* func) { indent++; break; } + case StackInst::Delegate: { + controlFlowDepth--; + indent--; + doIndent(); + printMedium(o, "delegate "); + Try* curr = inst->origin->cast<Try>(); + if (curr->delegateTarget == DELEGATE_CALLER_TARGET) { + o << controlFlowDepth; + } else { + printName(curr->delegateTarget, o); + } + break; + } default: WASM_UNREACHABLE("unexpeted op"); } std::cout << '\n'; } + assert(controlFlowDepth == 0); return o; } diff --git a/src/passes/RemoveUnusedNames.cpp b/src/passes/RemoveUnusedNames.cpp index 64640aefe..53da00733 100644 --- a/src/passes/RemoveUnusedNames.cpp +++ b/src/passes/RemoveUnusedNames.cpp @@ -83,6 +83,8 @@ struct RemoveUnusedNames } } + void visitTry(Try* curr) { handleBreakTarget(curr->name); } + void visitFunction(Function* curr) { assert(branchesSeen.empty()); } }; diff --git a/src/passes/StackIR.cpp b/src/passes/StackIR.cpp index 0732a6499..6d163d897 100644 --- a/src/passes/StackIR.cpp +++ b/src/passes/StackIR.cpp @@ -258,6 +258,7 @@ private: case StackInst::LoopEnd: case StackInst::Catch: case StackInst::CatchAll: + case StackInst::Delegate: case StackInst::TryEnd: { return true; } @@ -284,7 +285,8 @@ private: case StackInst::BlockEnd: case StackInst::IfEnd: case StackInst::LoopEnd: - case StackInst::TryEnd: { + case StackInst::TryEnd: + case StackInst::Delegate: { return true; } default: { return false; } diff --git a/src/shared-constants.h b/src/shared-constants.h index 569fd792d..5520f15ac 100644 --- a/src/shared-constants.h +++ b/src/shared-constants.h @@ -60,6 +60,7 @@ extern Name CASE; extern Name BR; extern Name FUNCREF; extern Name FAKE_RETURN; +extern Name DELEGATE_CALLER_TARGET; extern Name MUT; extern Name SPECTEST; extern Name PRINT; diff --git a/src/wasm-binary.h b/src/wasm-binary.h index a4d41530e..c2a771a7d 100644 --- a/src/wasm-binary.h +++ b/src/wasm-binary.h @@ -1027,6 +1027,7 @@ enum ASTNodes { Try = 0x06, Catch = 0x07, CatchAll = 0x05, + Delegate = 0x18, Throw = 0x08, Rethrow = 0x09, @@ -1417,6 +1418,8 @@ public: // the names that breaks target. this lets us know if a block has breaks to it // or not. std::unordered_set<Name> breakTargetNames; + // the names that delegates target. + std::unordered_set<Name> delegateTargetNames; std::vector<Expression*> expressionStack; @@ -1521,6 +1524,7 @@ public: Expression* getBlockOrSingleton(Type type); BreakTarget getBreakTarget(int32_t offset); + Name getDelegateTargetName(int32_t offset); void readMemoryAccess(Address& alignment, Address& offset); diff --git a/src/wasm-delegations-fields.h b/src/wasm-delegations-fields.h index 033da6314..9677aa4de 100644 --- a/src/wasm-delegations-fields.h +++ b/src/wasm-delegations-fields.h @@ -515,8 +515,10 @@ switch (DELEGATE_ID) { } case Expression::Id::TryId: { DELEGATE_START(Try); + DELEGATE_FIELD_SCOPE_NAME_USE(Try, delegateTarget); DELEGATE_FIELD_CHILD_VECTOR(Try, catchBodies); DELEGATE_FIELD_NAME_VECTOR(Try, catchEvents); + DELEGATE_FIELD_SCOPE_NAME_DEF(Try, name); DELEGATE_FIELD_CHILD(Try, body); DELEGATE_END(Try); break; diff --git a/src/wasm-s-parser.h b/src/wasm-s-parser.h index 8a92c0935..92bc55d0a 100644 --- a/src/wasm-s-parser.h +++ b/src/wasm-s-parser.h @@ -242,7 +242,8 @@ private: i++; } } - Name getLabel(Element& s); + enum class LabelType { Break, Delegate }; + Name getLabel(Element& s, LabelType labelType = LabelType::Break); Expression* makeBreak(Element& s); Expression* makeBreakTable(Element& s); Expression* makeReturn(Element& s); diff --git a/src/wasm-stack.h b/src/wasm-stack.h index bd44ed72e..7f94573fa 100644 --- a/src/wasm-stack.h +++ b/src/wasm-stack.h @@ -71,6 +71,7 @@ public: TryBegin, // the beginning of a try Catch, // the catch within a try CatchAll, // the catch_all within a try + Delegate, // the delegate within a try TryEnd // the ending of a try } op; @@ -109,6 +110,7 @@ public: void emitIfElse(If* curr); void emitCatch(Try* curr, Index i); void emitCatchAll(Try* curr); + void emitDelegate(Try* curr); // emit an end at the end of a block/loop/if/try void emitScopeEnd(Expression* curr); // emit an end at the end of a function @@ -169,6 +171,9 @@ private: void emitCatchAll(Try* curr) { static_cast<SubType*>(this)->emitCatchAll(curr); } + void emitDelegate(Try* curr) { + static_cast<SubType*>(this)->emitDelegate(curr); + } void emitScopeEnd(Expression* curr) { static_cast<SubType*>(this)->emitScopeEnd(curr); } @@ -343,7 +348,11 @@ template<typename SubType> void BinaryenIRWriter<SubType>::visitTry(Try* curr) { emitCatchAll(curr); visitPossibleBlockContents(curr->catchBodies.back()); } - emitScopeEnd(curr); + if (curr->isDelegate()) { + emitDelegate(curr); + } else { + emitScopeEnd(curr); + } if (curr->type == Type::unreachable) { emitUnreachable(); } @@ -375,6 +384,7 @@ public: void emitIfElse(If* curr) { writer.emitIfElse(curr); } void emitCatch(Try* curr, Index i) { writer.emitCatch(curr, i); } void emitCatchAll(Try* curr) { writer.emitCatchAll(curr); } + void emitDelegate(Try* curr) { writer.emitDelegate(curr); } void emitScopeEnd(Expression* curr) { writer.emitScopeEnd(curr); } void emitFunctionEnd() { if (func->epilogLocation.size()) { @@ -414,6 +424,9 @@ public: void emitCatchAll(Try* curr) { stackIR.push_back(makeStackInst(StackInst::CatchAll, curr)); } + void emitDelegate(Try* curr) { + stackIR.push_back(makeStackInst(StackInst::Delegate, curr)); + } void emitFunctionEnd() {} void emitUnreachable() { stackIR.push_back(makeStackInst(Builder(module).makeUnreachable())); diff --git a/src/wasm-type.h b/src/wasm-type.h index fe1b832bc..4188c438d 100644 --- a/src/wasm-type.h +++ b/src/wasm-type.h @@ -137,7 +137,6 @@ public: bool isRef() const; bool isFunction() const; bool isData() const; - bool isException() const; bool isNullable() const; bool isRtt() const; bool isStruct() const; diff --git a/src/wasm.h b/src/wasm.h index 7fd284756..876a9bfa7 100644 --- a/src/wasm.h +++ b/src/wasm.h @@ -1306,13 +1306,17 @@ class Try : public SpecificExpression<Expression::TryId> { public: Try(MixedArena& allocator) : catchEvents(allocator), catchBodies(allocator) {} + Name name; // label that can only be targeted by 'delegate's Expression* body; ArenaVector<Name> catchEvents; ExpressionList catchBodies; + Name delegateTarget; // target try's label bool hasCatchAll() const { return catchBodies.size() - catchEvents.size() == 1; } + bool isCatch() const { return !catchBodies.empty(); } + bool isDelegate() const { return delegateTarget.is(); } void finalize(); void finalize(Type type_); }; diff --git a/src/wasm/wasm-binary.cpp b/src/wasm/wasm-binary.cpp index f3ec376d1..878293caa 100644 --- a/src/wasm/wasm-binary.cpp +++ b/src/wasm/wasm-binary.cpp @@ -1918,7 +1918,9 @@ void WasmBinaryBuilder::readFunctions() { debugLocation.clear(); willBeIgnored = false; // process body - assert(breakTargetNames.size() == 0); + assert(breakStack.empty()); + assert(breakTargetNames.empty()); + assert(delegateTargetNames.empty()); assert(breakStack.empty()); assert(expressionStack.empty()); assert(controlFlowStack.empty()); @@ -1926,8 +1928,9 @@ void WasmBinaryBuilder::readFunctions() { assert(depth == 0); func->body = getBlockOrSingleton(func->sig.results); assert(depth == 0); - assert(breakStack.size() == 0); - assert(breakTargetNames.size() == 0); + assert(breakStack.empty()); + assert(breakTargetNames.empty()); + assert(delegateTargetNames.empty()); if (!expressionStack.empty()) { throwError("stack not empty on function exit"); } @@ -2210,7 +2213,8 @@ void WasmBinaryBuilder::processExpressions() { } auto peek = input[pos]; if (peek == BinaryConsts::End || peek == BinaryConsts::Else || - peek == BinaryConsts::Catch || peek == BinaryConsts::CatchAll) { + peek == BinaryConsts::Catch || peek == BinaryConsts::CatchAll || + peek == BinaryConsts::Delegate) { BYN_TRACE("== processExpressions finished with unreachable" << std::endl); lastSeparator = BinaryConsts::ASTNodes(peek); @@ -2987,6 +2991,14 @@ BinaryConsts::ASTNodes WasmBinaryBuilder::readExpression(Expression*& curr) { } break; } + case BinaryConsts::Delegate: { + curr = nullptr; + if (DWARF && currFunction) { + assert(!controlFlowStack.empty()); + controlFlowStack.pop_back(); + } + break; + } case BinaryConsts::RefNull: visitRefNull((curr = allocator.alloc<RefNull>())->cast<RefNull>()); break; @@ -3376,7 +3388,8 @@ Expression* WasmBinaryBuilder::getBlockOrSingleton(Type type) { block->name = label; block->finalize(type); // maybe we don't need a block here? - if (breakTargetNames.find(block->name) == breakTargetNames.end()) { + if (breakTargetNames.find(block->name) == breakTargetNames.end() && + delegateTargetNames.find(block->name) == delegateTargetNames.end()) { block->name = Name(); if (block->list.size() == 1) { return block->list[0]; @@ -3452,6 +3465,28 @@ WasmBinaryBuilder::getBreakTarget(int32_t offset) { return ret; } +Name WasmBinaryBuilder::getDelegateTargetName(int32_t offset) { + BYN_TRACE("getDelegateTarget " << offset << std::endl); + // We always start parsing a function by creating a block label and pushing it + // in breakStack in getBlockOrSingleton, so if a 'delegate''s target is that + // block, it does not mean it targets that block; it throws to the caller. + if (breakStack.size() - 1 == size_t(offset)) { + return DELEGATE_CALLER_TARGET; + } + size_t index = breakStack.size() - 1 - offset; + if (index > breakStack.size()) { + throwError("bad delegate index (high)"); + } + BYN_TRACE("delegate target " << breakStack[index].name << std::endl); + auto& ret = breakStack[index]; + // if the delegate is in literally unreachable code, then we will not emit it + // anyhow, so do not note that the target has delegate to it + if (!willBeIgnored) { + delegateTargetNames.insert(ret.name); + } + return ret.name; +} + void WasmBinaryBuilder::visitBreak(Break* curr, uint8_t code) { BYN_TRACE("zz node: Break, code " << int32_t(code) << std::endl); BreakTarget target = getBreakTarget(getU32LEB()); @@ -5746,58 +5781,13 @@ void WasmBinaryBuilder::visitTryOrTryInBlock(Expression*& out) { curr->type = getType(); curr->body = getBlockOrSingleton(curr->type); if (lastSeparator != BinaryConsts::Catch && - lastSeparator != BinaryConsts::CatchAll) { + lastSeparator != BinaryConsts::CatchAll && + lastSeparator != BinaryConsts::Delegate) { throwError("No catch instruction within a try scope"); } - // For simplicity, we create an inner block within the catch body too, but the - // one within the 'catch' *must* be omitted when we write out the binary back - // later, because the 'catch' instruction pushes a value onto the stack and - // the inner block does not support block input parameters without multivalue - // support. - // try - // ... - // catch ;; Pushes a value onto the stack - // block ;; Inner block. Should be deleted when writing binary! - // use the pushed value - // end - // end - // - // But when input binary code is like - // try - // ... - // catch - // br 0 - // end - // - // 'br 0' accidentally happens to target the inner block, creating code like - // this in Binaryen IR, making the inner block not deletable, resulting in a - // validation error: - // (try - // ... - // (catch - // (block $label0 ;; Cannot be deleted, because there's a branch to this - // ... - // (br $label0) - // ) - // ) - // ) - // - // When this happens, we fix this by creating a block that wraps the whole - // try-catch, and making the branches target that block instead, like this: - // (block $label ;; New enclosing block, new target for the branch - // (try - // ... - // (catch - // (block ;; Now this can be deleted when writing binary - // ... - // (br $label0) - // ) - // ) - // ) - // ) - Builder builder(wasm); + // A nameless label shared by all catch body blocks Name catchLabel = getNextLabel(); breakStack.push_back({catchLabel, curr->type}); @@ -5839,8 +5829,84 @@ void WasmBinaryBuilder::visitTryOrTryInBlock(Expression*& out) { readCatchBody(Type::none); } } + breakStack.pop_back(); + + if (lastSeparator == BinaryConsts::Delegate) { + curr->delegateTarget = getDelegateTargetName(getU32LEB()); + } + + // For simplicity, we make try's labels only can be targeted by delegates, and + // delegates can only target try's labels. (If they target blocks or loops, it + // is a validation failure.) Because we create an inner block within each try + // and catch body, if any delegate targets those inner blocks, we should make + // them target the try's label instead. + curr->name = getNextLabel(); + if (auto* block = curr->body->dynCast<Block>()) { + if (block->name.is()) { + if (delegateTargetNames.find(block->name) != delegateTargetNames.end()) { + BranchUtils::replaceDelegateTargets(block, block->name, curr->name); + delegateTargetNames.erase(block->name); + } + // maybe we don't need a block here? + if (block->list.size() == 1) { + curr->body = block->list[0]; + } + } + } + if (delegateTargetNames.find(catchLabel) != delegateTargetNames.end()) { + for (auto* catchBody : curr->catchBodies) { + BranchUtils::replaceDelegateTargets(catchBody, catchLabel, curr->name); + } + delegateTargetNames.erase(catchLabel); + } curr->finalize(curr->type); + // For simplicity, we create an inner block within the catch body too, but the + // one within the 'catch' *must* be omitted when we write out the binary back + // later, because the 'catch' instruction pushes a value onto the stack and + // the inner block does not support block input parameters without multivalue + // support. + // try + // ... + // catch $e ;; Pushes value(s) onto the stack + // block ;; Inner block. Should be deleted when writing binary! + // use the pushed value + // end + // end + // + // But when input binary code is like + // try + // ... + // catch $e + // br 0 + // end + // + // 'br 0' accidentally happens to target the inner block, creating code like + // this in Binaryen IR, making the inner block not deletable, resulting in a + // validation error: + // (try + // ... + // (catch $e + // (block $label0 ;; Cannot be deleted, because there's a branch to this + // ... + // (br $label0) + // ) + // ) + // ) + // + // When this happens, we fix this by creating a block that wraps the whole + // try-catch, and making the branches target that block instead, like this: + // (block $label ;; New enclosing block, new target for the branch + // (try + // ... + // (catch $e + // (block ;; Now this can be deleted when writing binary + // ... + // (br $label0) + // ) + // ) + // ) + // ) if (breakTargetNames.find(catchLabel) == breakTargetNames.end()) { out = curr; } else { @@ -5848,7 +5914,6 @@ void WasmBinaryBuilder::visitTryOrTryInBlock(Expression*& out) { auto* block = builder.makeBlock(catchLabel, curr); out = block; } - breakStack.pop_back(); breakTargetNames.erase(catchLabel); } diff --git a/src/wasm/wasm-s-parser.cpp b/src/wasm/wasm-s-parser.cpp index bcce3993e..d2b24fbed 100644 --- a/src/wasm/wasm-s-parser.cpp +++ b/src/wasm/wasm-s-parser.cpp @@ -1859,7 +1859,7 @@ Expression* SExpressionWasmBuilder::makeCallIndirect(Element& s, return ret; } -Name SExpressionWasmBuilder::getLabel(Element& s) { +Name SExpressionWasmBuilder::getLabel(Element& s, LabelType labelType) { if (s.dollared()) { return nameMapper.sourceToUnique(s.str()); } else { @@ -1876,10 +1876,14 @@ Name SExpressionWasmBuilder::getLabel(Element& s) { throw ParseException("invalid label", s.line, s.col); } if (offset == nameMapper.labelStack.size()) { - // a break to the function's scope. this means we need an automatic block, - // with a name - brokeToAutoBlock = true; - return FAKE_RETURN; + if (labelType == LabelType::Break) { + // a break to the function's scope. this means we need an automatic + // block, with a name + brokeToAutoBlock = true; + return FAKE_RETURN; + } + // This is a delegate that delegates to the caller + return DELEGATE_CALLER_TARGET; } return nameMapper.labelStack[nameMapper.labelStack.size() - 1 - offset]; } @@ -1975,12 +1979,13 @@ Expression* SExpressionWasmBuilder::makeRefEq(Element& s) { return ret; } -// try-catch-end is written in the folded wast format as +// try can be either in the form of try-catch or try-delegate. +// try-catch is written in the folded wast format as // (try // (do // ... // ) -// (catch +// (catch $e // ... // ) // ... @@ -1991,6 +1996,14 @@ Expression* SExpressionWasmBuilder::makeRefEq(Element& s) { // Any number of catch blocks can exist, including none. Zero or one catch_all // block can exist, and if it does, it should be at the end. There should be at // least one catch or catch_all body per try. +// +// try-delegate is written in the folded format as +// (try +// (do +// ... +// ) +// (delegate $label) +// ) Expression* SExpressionWasmBuilder::makeTry(Element& s) { auto ret = allocator.alloc<Try>(); Index i = 1; @@ -2001,7 +2014,7 @@ Expression* SExpressionWasmBuilder::makeTry(Element& s) { } else { sName = "try"; } - auto label = nameMapper.pushLabelName(sName); + ret->name = nameMapper.pushLabelName(sName); Type type = parseOptionalResultType(s, i); // signature if (!elementStartsWith(*s[i], "do")) { @@ -2027,21 +2040,38 @@ Expression* SExpressionWasmBuilder::makeTry(Element& s) { ret->catchBodies.push_back(makeMaybeBlock(*s[i++], 1, type)); } + // 'delegate' cannot target its own try. So we pop the name here. + nameMapper.popLabelName(ret->name); + + if (i < s.size() && elementStartsWith(*s[i], "delegate")) { + Element& inner = *s[i++]; + if (inner.size() != 2) { + throw ParseException("invalid delegate", inner.line, inner.col); + } + ret->delegateTarget = getLabel(*inner[1], LabelType::Delegate); + } + if (i != s.size()) { throw ParseException( "there should be at most one catch_all block at the end", s.line, s.col); } - if (ret->catchBodies.empty()) { - throw ParseException("no catch bodies", s.line, s.col); + if (ret->catchBodies.empty() && !ret->isDelegate()) { + throw ParseException("no catch bodies or delegate", s.line, s.col); } ret->finalize(type); - nameMapper.popLabelName(label); + // create a break target if we must - if (BranchUtils::BranchSeeker::has(ret, label)) { + if (BranchUtils::BranchSeeker::has(ret, ret->name)) { auto* block = allocator.alloc<Block>(); - block->name = label; + // We create a different name for the wrapping block, because try's name can + // be used by internal delegates + block->name = nameMapper.pushLabelName(sName); + // For simplicity, try's name canonly be targeted by delegates. Make the + // branches target the new wrapping block instead. + BranchUtils::replaceBranchTargets(ret, ret->name, block->name); block->list.push_back(ret); + nameMapper.popLabelName(block->name); block->finalize(type); return block; } diff --git a/src/wasm/wasm-stack.cpp b/src/wasm/wasm-stack.cpp index 00b1e5368..cb9d94093 100644 --- a/src/wasm/wasm-stack.cpp +++ b/src/wasm/wasm-stack.cpp @@ -1904,7 +1904,7 @@ void BinaryInstWriter::visitRefEq(RefEq* curr) { } void BinaryInstWriter::visitTry(Try* curr) { - breakStack.emplace_back(IMPOSSIBLE_CONTINUE); + breakStack.push_back(curr->name); o << int8_t(BinaryConsts::Try); emitResultType(curr->type); } @@ -1924,6 +1924,13 @@ void BinaryInstWriter::emitCatchAll(Try* curr) { o << int8_t(BinaryConsts::CatchAll); } +void BinaryInstWriter::emitDelegate(Try* curr) { + assert(!breakStack.empty()); + breakStack.pop_back(); + o << int8_t(BinaryConsts::Delegate) + << U32LEB(getBreakIndex(curr->delegateTarget)); +} + void BinaryInstWriter::visitThrow(Throw* curr) { o << int8_t(BinaryConsts::Throw) << U32LEB(parent.getEventIndex(curr->event)); } @@ -2216,6 +2223,9 @@ void BinaryInstWriter::emitMemoryAccess(size_t alignment, } int32_t BinaryInstWriter::getBreakIndex(Name name) { // -1 if not found + if (name == DELEGATE_CALLER_TARGET) { + return breakStack.size(); + } for (int i = breakStack.size() - 1; i >= 0; i--) { if (breakStack[i] == name) { return breakStack.size() - 1 - i; @@ -2321,6 +2331,10 @@ void StackIRToBinaryWriter::write() { writer.emitCatchAll(inst->origin->cast<Try>()); break; } + case StackInst::Delegate: { + writer.emitDelegate(inst->origin->cast<Try>()); + break; + } default: WASM_UNREACHABLE("unexpected op"); } diff --git a/src/wasm/wasm-validator.cpp b/src/wasm/wasm-validator.cpp index 276b9602f..beb994390 100644 --- a/src/wasm/wasm-validator.cpp +++ b/src/wasm/wasm-validator.cpp @@ -236,6 +236,7 @@ struct FunctionValidator : public WalkerPass<PostWalker<FunctionValidator>> { }; std::unordered_map<Name, BreakInfo> breakInfos; + std::unordered_set<Name> delegateTargetNames; std::set<Type> returnTypes; // types used in returns @@ -276,11 +277,52 @@ public: void visitLoop(Loop* curr); void visitIf(If* curr); + static void visitPreTry(FunctionValidator* self, Expression** currp) { + auto* curr = (*currp)->cast<Try>(); + if (curr->name.is()) { + self->delegateTargetNames.insert(curr->name); + } + } + + // We remove try's label before proceeding to verify catch bodies because the + // following is a validation failure: + // (try $l0 + // (do ... ) + // (catch $e + // (try + // (do ...) + // (delegate $l0) ;; validation failure + // ) + // ) + // ) + // Unlike branches, if delegate's target 'catch' is located above the + // delegate, it is a validation failure. + static void visitPreCatch(FunctionValidator* self, Expression** currp) { + auto* curr = (*currp)->cast<Try>(); + if (curr->name.is()) { + self->delegateTargetNames.erase(curr->name); + } + } + // override scan to add a pre and a post check task to all nodes static void scan(FunctionValidator* self, Expression** currp) { + auto* curr = *currp; + // Treat 'Try' specially because we need to run visitPreCatch between the + // try body and catch bodies + if (curr->is<Try>()) { + self->pushTask(doVisitTry, currp); + auto& list = curr->cast<Try>()->catchBodies; + for (int i = int(list.size()) - 1; i >= 0; i--) { + self->pushTask(scan, &list[i]); + } + self->pushTask(visitPreCatch, currp); + self->pushTask(scan, &curr->cast<Try>()->body); + self->pushTask(visitPreTry, currp); + return; + } + PostWalker<FunctionValidator>::scan(self, currp); - auto* curr = *currp; if (curr->is<Block>()) { self->pushTask(visitPreBlock, currp); } @@ -334,6 +376,7 @@ public: void visitRefIs(RefIs* curr); void visitRefFunc(RefFunc* curr); void visitRefEq(RefEq* curr); + void noteDelegate(Name name, Expression* curr); void visitTry(Try* curr); void visitThrow(Throw* curr); void visitRethrow(Rethrow* curr); @@ -767,6 +810,7 @@ void FunctionValidator::noteBreak(Name name, Type valueType, Expression* curr) { } } } + void FunctionValidator::visitBreak(Break* curr) { noteBreak(curr->name, curr->value, curr); if (curr->value) { @@ -2029,6 +2073,14 @@ void FunctionValidator::visitRefEq(RefEq* curr) { "ref.eq's right argument should be a subtype of eqref"); } +void FunctionValidator::noteDelegate(Name name, Expression* curr) { + if (name != DELEGATE_CALLER_TARGET) { + shouldBeTrue(delegateTargetNames.find(name) != delegateTargetNames.end(), + curr, + "all delegate targets must be valid"); + } +} + void FunctionValidator::visitTry(Try* curr) { shouldBeTrue(getModule()->features.hasExceptionHandling(), curr, @@ -2061,6 +2113,17 @@ void FunctionValidator::visitTry(Try* curr) { shouldBeTrue(curr->catchBodies.size() - curr->catchEvents.size() <= 1, curr, "the number of catch blocks and events do not match"); + + shouldBeFalse(curr->isCatch() && curr->isDelegate(), + curr, + "try cannot have both catch and delegate at the same time"); + shouldBeTrue(curr->isCatch() || curr->isDelegate(), + curr, + "try should have either catches or a delegate"); + + if (curr->isDelegate()) { + noteDelegate(curr->delegateTarget, curr); + } } void FunctionValidator::visitThrow(Throw* curr) { @@ -2470,6 +2533,9 @@ void FunctionValidator::visitFunction(Function* curr) { shouldBeTrue( breakInfos.empty(), curr->body, "all named break targets must exist"); + shouldBeTrue(delegateTargetNames.empty(), + curr->body, + "all named delegate targets must exist"); returnTypes.clear(); labelNames.clear(); // validate optional local names diff --git a/src/wasm/wasm.cpp b/src/wasm/wasm.cpp index 7bf9b8604..92e03f579 100644 --- a/src/wasm/wasm.cpp +++ b/src/wasm/wasm.cpp @@ -88,6 +88,7 @@ Name CASE("case"); Name BR("br"); Name FUNCREF("funcref"); Name FAKE_RETURN("fake_return_waka123"); +Name DELEGATE_CALLER_TARGET("delegate_caller_target_waka123"); Name MUT("mut"); Name SPECTEST("spectest"); Name PRINT("print"); |