mirror of
https://github.com/ethereum/solidity
synced 2023-10-03 13:03:40 +00:00
35 lines
1.1 KiB
Solidity
35 lines
1.1 KiB
Solidity
contract C {
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function g() public returns (uint ret) {
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uint x = type(uint).max;
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assembly {
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mstore(0x20, x)
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// both old and new optimizer should be able to evaluate this
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ret := keccak256(0x20, 16)
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}
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}
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function f() public returns (uint ret) {
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uint x = type(uint).max;
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assembly {
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mstore(0x20, x)
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// For Yul optimizer, load resolver and loop invariant code motion
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// would take the Keccak-256 outside the loop. For the old-optimizer,
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// this is not possible.
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// Net savings approximately: 20 * cost of Keccak-256 = 572
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for {let i := 0} lt(i, 20) { i := add(i, 1) } {
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ret := keccak256(0x20, 16)
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}
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}
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}
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}
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// ====
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// ----
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// f() -> 0xcdb56c384a9682c600315e3470157a4cf7638d0d33e9dae5c40ffd2644fc5a80
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// gas irOptimized: 22239
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// gas legacy: 23385
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// gas legacyOptimized: 23092
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// g() -> 0xcdb56c384a9682c600315e3470157a4cf7638d0d33e9dae5c40ffd2644fc5a80
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// gas irOptimized: 21277
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// gas legacy: 21462
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// gas legacyOptimized: 21256
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