diff options
| -rw-r--r-- | src/passes/DeadArgumentElimination.cpp | 7 | ||||
| -rw-r--r-- | test/lit/passes/dae_tnh.wast | 34 |
2 files changed, 38 insertions, 3 deletions
diff --git a/src/passes/DeadArgumentElimination.cpp b/src/passes/DeadArgumentElimination.cpp index e95dc3ff9..7ebed7127 100644 --- a/src/passes/DeadArgumentElimination.cpp +++ b/src/passes/DeadArgumentElimination.cpp @@ -383,13 +383,14 @@ struct DAE : public Pass { while (1) { if (infoMap[name].unusedParams.has(i)) { // Great, it's not used. Check if none of the calls has a param with - // side effects, as that would prevent us removing them (flattening - // should have been done earlier). + // side effects that we cannot remove (as if we can remove them, we + // will simply do that when we remove the parameter). Note: flattening + // the IR beforehand can help here. bool callParamsAreValid = std::none_of(calls.begin(), calls.end(), [&](Call* call) { auto* operand = call->operands[i]; return EffectAnalyzer(runner->options, *module, operand) - .hasSideEffects(); + .hasUnremovableSideEffects(); }); // The type must be valid for us to handle as a local (since we // replace the parameter with a local). diff --git a/test/lit/passes/dae_tnh.wast b/test/lit/passes/dae_tnh.wast new file mode 100644 index 000000000..fc9270cf3 --- /dev/null +++ b/test/lit/passes/dae_tnh.wast @@ -0,0 +1,34 @@ +;; NOTE: Assertions have been generated by update_lit_checks.py --all-items and should not be edited. + +;; RUN: foreach %s %t wasm-opt --dae --all-features -tnh -S -o - | filecheck %s + +(module + ;; CHECK: (type $none_=>_none (func)) + + ;; CHECK: (type $ref?|$struct|_=>_none (func (param (ref null $struct)))) + + ;; CHECK: (type $struct (struct (field i32))) + (type $struct (struct_subtype (field i32) data)) + + ;; CHECK: (func $target + ;; CHECK-NEXT: (local $0 i32) + ;; CHECK-NEXT: (nop) + ;; CHECK-NEXT: ) + (func $target (param $x i32) + (nop) + ) + + ;; CHECK: (func $caller (param $ref (ref null $struct)) + ;; CHECK-NEXT: (call $target) + ;; CHECK-NEXT: ) + (func $caller (param $ref (ref null $struct)) + (call $target + ;; This might trap in theory, but in traps-never-happen mode which is + ;; enabled here, we can ignore and remove such side effects, allowing us + ;; to optimize away this parameter which is never used. + (struct.get $struct 0 + (local.get $ref) + ) + ) + ) +) |