2 Commits (b57680b0b21036460c689aab1e82d89297738d50)

Author	SHA1	Message	Date
Felix Lange	5c8fe28b72	common: move big integer math to common/math (#3699) ... * common: remove CurrencyToString Move denomination values to params instead. * common: delete dead code * common: move big integer operations to common/math This commit consolidates all big integer operations into common/math and adds tests and documentation. There should be no change in semantics for BigPow, BigMin, BigMax, S256, U256, Exp and their behaviour is now locked in by tests. The BigD, BytesToBig and Bytes2Big functions don't provide additional value, all uses are replaced by new(big.Int).SetBytes(). BigToBytes is now called PaddedBigBytes, its minimum output size parameter is now specified as the number of bytes instead of bits. The single use of this function is in the EVM's MSTORE instruction. Big and String2Big are replaced by ParseBig, which is slightly stricter. It previously accepted leading zeros for hexadecimal inputs but treated decimal inputs as octal if a leading zero digit was present. ParseUint64 is used in places where String2Big was used to decode a uint64. The new functions MustParseBig and MustParseUint64 are now used in many places where parsing errors were previously ignored. * common: delete unused big integer variables * accounts/abi: replace uses of BytesToBig with use of encoding/binary * common: remove BytesToBig * common: remove Bytes2Big * common: remove BigTrue * cmd/utils: add BigFlag and use it for error-checked integer flags While here, remove environment variable processing for DirectoryFlag because we don't use it. * core: add missing error checks in genesis block parser * common: remove String2Big * cmd/evm: use utils.BigFlag * common/math: check for 256 bit overflow in ParseBig This is supposed to prevent silent overflow/truncation of values in the genesis block JSON. Without this check, a genesis block that set a balance larger than 256 bits would lead to weird behaviour in the VM. * cmd/utils: fixup import	8 years ago
Jeffrey Wilcke	bbc4ea4ae8	core/vm: improved EVM run loop & instruction calling (#3378) ... The run loop, which previously contained custom opcode executes have been removed and has been simplified to a few checks. Each operation consists of 4 elements: execution function, gas cost function, stack validation function and memory size function. The execution function implements the operation's runtime behaviour, the gas cost function implements the operation gas costs function and greatly depends on the memory and stack, the stack validation function validates the stack and makes sure that enough items can be popped off and pushed on and the memory size function calculates the memory required for the operation and returns it. This commit also allows the EVM to go unmetered. This is helpful for offline operations such as contract calls.	8 years ago