diff options
| -rw-r--r-- | src/ast_utils.h | 31 | ||||
| -rw-r--r-- | src/pass.cpp | 2 | ||||
| -rw-r--r-- | src/passes/Print.cpp | 5 | ||||
| -rw-r--r-- | src/passes/Vacuum.cpp | 8 | ||||
| -rw-r--r-- | test/unit.fromasm | 19 | ||||
| -rw-r--r-- | test/unit.fromasm.imprecise | 19 |
6 files changed, 62 insertions, 22 deletions
diff --git a/src/ast_utils.h b/src/ast_utils.h index f91cfab24..9336d2b3a 100644 --- a/src/ast_utils.h +++ b/src/ast_utils.h @@ -117,6 +117,37 @@ struct ExpressionManipulator { } }; +struct ExpressionAnalyzer { + // Given a stack of expressions, checks if the topmost is used as a result. + // For example, if the parent is a block and the node is before the last position, + // it is not used. + static bool isResultUsed(std::vector<Expression*> stack, Function* func) { + for (int i = int(stack.size()) - 2; i >= 0; i--) { + auto* curr = stack[i]; + auto* above = stack[i + 1]; + // only if and block can drop values + if (curr->is<Block>()) { + auto* block = curr->cast<Block>(); + for (size_t j = 0; j < block->list.size() - 1; j++) { + if (block->list[j] == above) return false; + } + assert(block->list.back() == above); + // continue down + } else if (curr->is<If>()) { + auto* iff = curr->cast<If>(); + if (!iff->ifFalse) return false; + if (above == iff->condition) return true; + assert(above == iff->ifTrue || above == iff->ifFalse); + // continue down + } else { + return true; // all other node types use the result + } + } + // The value might be used, so it depends on if the function returns + return func->result != none; + } +}; + } // namespace wasm #endif // wasm_ast_utils_h diff --git a/src/pass.cpp b/src/pass.cpp index 1a8aaabc9..7095da71d 100644 --- a/src/pass.cpp +++ b/src/pass.cpp @@ -60,9 +60,9 @@ std::string PassRegistry::getPassDescription(std::string name) { void PassRunner::addDefaultOptimizationPasses() { add("remove-unused-brs"); add("remove-unused-names"); - add("merge-blocks"); add("optimize-instructions"); add("simplify-locals"); + add("merge-blocks"); add("reorder-locals"); add("vacuum"); } diff --git a/src/passes/Print.cpp b/src/passes/Print.cpp index ddeec3dce..59ade1c76 100644 --- a/src/passes/Print.cpp +++ b/src/passes/Print.cpp @@ -68,7 +68,10 @@ struct PrintSExpression : public Visitor<PrintSExpression> { } Name printableLocal(Index index) { - Name name = currFunction->tryLocalName(index); + Name name; + if (currFunction) { + name = currFunction->tryLocalName(index); + } if (!name.is()) { name = Name::fromInt(index); } diff --git a/src/passes/Vacuum.cpp b/src/passes/Vacuum.cpp index dfede6d25..863d78f14 100644 --- a/src/passes/Vacuum.cpp +++ b/src/passes/Vacuum.cpp @@ -20,6 +20,7 @@ #include <wasm.h> #include <pass.h> +#include <ast_utils.h> namespace wasm { @@ -41,6 +42,13 @@ struct Vacuum : public WalkerPass<PostWalker<Vacuum, Visitor<Vacuum>>> { if (skip > 0) { list.resize(size - skip); } + if (!curr->name.is()) { + if (list.size() == 1) { + replaceCurrent(list[0]); + } else if (list.size() == 0) { + ExpressionManipulator::nop(curr); + } + } } }; diff --git a/test/unit.fromasm b/test/unit.fromasm index 9a142a142..0b43f14fc 100644 --- a/test/unit.fromasm +++ b/test/unit.fromasm @@ -272,6 +272,7 @@ ) ) (func $blocker + (nop) ) (func $frem (result f64) (return @@ -311,19 +312,17 @@ ) (func $abs (local $asm2wasm_i32_temp i32) - (block - (select - (i32.sub + (select + (i32.sub + (i32.const 0) + (set_local $asm2wasm_i32_temp (i32.const 0) - (set_local $asm2wasm_i32_temp - (i32.const 0) - ) ) + ) + (get_local $asm2wasm_i32_temp) + (i32.lt_s (get_local $asm2wasm_i32_temp) - (i32.lt_s - (get_local $asm2wasm_i32_temp) - (i32.const 0) - ) + (i32.const 0) ) ) (f64.abs diff --git a/test/unit.fromasm.imprecise b/test/unit.fromasm.imprecise index e829c7f3c..f5ba55d90 100644 --- a/test/unit.fromasm.imprecise +++ b/test/unit.fromasm.imprecise @@ -266,6 +266,7 @@ ) ) (func $blocker + (nop) ) (func $frem (result f64) (return @@ -305,19 +306,17 @@ ) (func $abs (local $asm2wasm_i32_temp i32) - (block - (select - (i32.sub + (select + (i32.sub + (i32.const 0) + (set_local $asm2wasm_i32_temp (i32.const 0) - (set_local $asm2wasm_i32_temp - (i32.const 0) - ) ) + ) + (get_local $asm2wasm_i32_temp) + (i32.lt_s (get_local $asm2wasm_i32_temp) - (i32.lt_s - (get_local $asm2wasm_i32_temp) - (i32.const 0) - ) + (i32.const 0) ) ) (f64.abs |