diff options
| -rw-r--r-- | src/passes/OptimizeInstructions.cpp | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/src/passes/OptimizeInstructions.cpp b/src/passes/OptimizeInstructions.cpp index dc38933a6..3b7a9dc6d 100644 --- a/src/passes/OptimizeInstructions.cpp +++ b/src/passes/OptimizeInstructions.cpp @@ -524,6 +524,10 @@ struct OptimizeInstructions if (right->type == Type::i32) { BinaryOp op; int32_t c = right->value.geti32(); + // First, try to lower signed operations to unsigned if that is + // possible. Some unsigned operations like div_u or rem_u are usually + // faster on VMs. Also this opens more possibilities for further + // simplifications afterwards. if (c >= 0 && (op = makeUnsignedBinaryOp(binary->op)) != InvalidBinary && Bits::getMaxBits(binary->left, this) <= 31) { @@ -545,6 +549,7 @@ struct OptimizeInstructions if (right->type == Type::i64) { BinaryOp op; int64_t c = right->value.geti64(); + // See description above for Type::i32 if (c >= 0 && (op = makeUnsignedBinaryOp(binary->op)) != InvalidBinary && Bits::getMaxBits(binary->left, this) <= 63) { |