CREATE opcode: what does it really do? The Next CEO of Stack OverflowWhat does bytecode of blank contract do?When does a SUICIDE opcode becomes effective?Possible to create new contract via a proposal in the ethereum.org/dao framework?What are the two arguments to a RETURN opcode?Can the CALL opcode be used to create a contract?Transaction Error. Exception thrown in contract code. REVERT opcode when sending ETH to crowdsaleWhat happens in CALL when gas is set to 0?Ethereum opcode: meaning of first few instructions?callvalue opcode, for what?EVM SIGNEXTEND Opcode explanation
Does it take more energy to get to Venus or to Mars?
Why does standard notation not preserve intervals (visually)
Why do we use the plural of movies in this phrase "We went to the movies last night."?
How to make a variable always equal to the result of some calculations?
How do I go from 300 unfinished/half written blog posts, to published posts?
Are there any limitations on attacking while grappling?
Anatomically Correct Strange Women In Ponds Distributing Swords
Inappropriate reference requests from Journal reviewers
What flight has the highest ratio of time difference to flight time?
Limits on contract work without pre-agreed price/contract (UK)
What benefits would be gained by using human laborers instead of drones in deep sea mining?
How do scammers retract money, while you can’t?
If Nick Fury and Coulson already knew about aliens (Kree and Skrull) why did they wait until Thor's appearance to start making weapons?
What is ( CFMCC ) on ILS approach chart?
Is it professional to write unrelated content in an almost-empty email?
What does convergence in distribution "in the Gromov–Hausdorff" sense mean?
Is there a way to save my career from absolute disaster?
Elegant way to replace substring in a regex with optional groups in Python?
Why is the US ranked as #45 in Press Freedom ratings, despite its extremely permissive free speech laws?
multiple labels for a single equation
Between two walls
What is the result of assigning to std::vector<T>::begin()?
Written every which way
What was the first Unix version to run on a microcomputer?
CREATE opcode: what does it really do?
The Next CEO of Stack OverflowWhat does bytecode of blank contract do?When does a SUICIDE opcode becomes effective?Possible to create new contract via a proposal in the ethereum.org/dao framework?What are the two arguments to a RETURN opcode?Can the CALL opcode be used to create a contract?Transaction Error. Exception thrown in contract code. REVERT opcode when sending ETH to crowdsaleWhat happens in CALL when gas is set to 0?Ethereum opcode: meaning of first few instructions?callvalue opcode, for what?EVM SIGNEXTEND Opcode explanation
I am looking at the docs, but cannot really understand what CREATE opcode does. I can tell that CREATE does create a new smart contract from a memory chunk, pass the gas value to this new contract, then returns. But before returning, does it execute the new contract?
This confuses me because looking at the disassembly code of the smart contract bytecode, after CREATE, I cannot see any call to CALL after that, but then I still see a call to RETURNDATASIZE, which I suppose only happen after CALL. Without CALL, where it get returned data from?
Any enlighten, please?
opcode create
asked 2 days ago
user311703user311703
1846
add a comment |
I am looking at the docs, but cannot really understand what CREATE opcode does. I can tell that CREATE does create a new smart contract from a memory chunk, pass the gas value to this new contract, then returns. But before returning, does it execute the new contract?
This confuses me because looking at the disassembly code of the smart contract bytecode, after CREATE, I cannot see any call to CALL after that, but then I still see a call to RETURNDATASIZE, which I suppose only happen after CALL. Without CALL, where it get returned data from?
Any enlighten, please?
opcode create
asked 2 days ago
user311703user311703
1846
add a comment |
I am looking at the docs, but cannot really understand what CREATE opcode does. I can tell that CREATE does create a new smart contract from a memory chunk, pass the gas value to this new contract, then returns. But before returning, does it execute the new contract?
This confuses me because looking at the disassembly code of the smart contract bytecode, after CREATE, I cannot see any call to CALL after that, but then I still see a call to RETURNDATASIZE, which I suppose only happen after CALL. Without CALL, where it get returned data from?
Any enlighten, please?
opcode create
asked 2 days ago
user311703user311703
1846
I am looking at the docs, but cannot really understand what CREATE opcode does. I can tell that CREATE does create a new smart contract from a memory chunk, pass the gas value to this new contract, then returns. But before returning, does it execute the new contract?
This confuses me because looking at the disassembly code of the smart contract bytecode, after CREATE, I cannot see any call to CALL after that, but then I still see a call to RETURNDATASIZE, which I suppose only happen after CALL. Without CALL, where it get returned data from?
Any enlighten, please?
opcode create
opcode create
asked 2 days ago
user311703user311703
1846
asked 2 days ago
user311703user311703
1846
asked 2 days ago
user311703user311703
1846
asked 2 days ago
user311703user311703
1846
asked 2 days ago
user311703user311703
1846
1846
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
CREATE, in a way, does a built in CALL. What actually happens is that the data passed to call isn't the contract bytecode, it's the init bytecode.
When CREATE opcode is executed, the EVM creates a call frame in the context of the new contract (e.g. address(this) is the new contracts address). This executes the data passed to CREATE as the code, which in higher level languages is basically the constructor. At the end of this init stuff, it returns the actual code of the contract that is stored in the state trie.
The easiest way to think about it, which is also fairly accurate, is that the Solidity compiler takes all the executional code of the contract, compiles it to bytecode, and adds it as a return statement at the end of the constructor.
answered 2 days ago
flygoingflygoing
7,595931
ah, so CREATE when creating a contract actually returns the contract bytecode, right? then after that, CALL will actually executes the contract?
– user311703
2 days ago
Please could you tell me what is the best way to track/trace what is really happening at bytecode level? Does Remix a good tool to do this?
– user311703
2 days ago
1
CREATE executes the code passed to it, andthatcode returns the contact bytecode, yes. Just wanted to be clear on that
– flygoing
2 days ago
1
If you need to a call a function after it's created, then yeah, there would be aCALLright after. Remix is a pretty good way to track/trace on the bytecode level, it has pretty good EVM debugging tools for stepping in/out of bytecode
– flygoing
2 days ago
1
In that case theinitcode would just return the code for your contract. The compiler basically creates adefaultconstructor that does nothing but return the actual bytecode.
– flygoing
yesterday
|
show 1 more comment
Your Answer
StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "642"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);
else
createEditor();
);
function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);
);
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fethereum.stackexchange.com%2fquestions%2f68943%2fcreate-opcode-what-does-it-really-do%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
CREATE, in a way, does a built in CALL. What actually happens is that the data passed to call isn't the contract bytecode, it's the init bytecode.
When CREATE opcode is executed, the EVM creates a call frame in the context of the new contract (e.g. address(this) is the new contracts address). This executes the data passed to CREATE as the code, which in higher level languages is basically the constructor. At the end of this init stuff, it returns the actual code of the contract that is stored in the state trie.
The easiest way to think about it, which is also fairly accurate, is that the Solidity compiler takes all the executional code of the contract, compiles it to bytecode, and adds it as a return statement at the end of the constructor.
answered 2 days ago
flygoingflygoing
7,595931
ah, so CREATE when creating a contract actually returns the contract bytecode, right? then after that, CALL will actually executes the contract?
– user311703
2 days ago
Please could you tell me what is the best way to track/trace what is really happening at bytecode level? Does Remix a good tool to do this?
– user311703
2 days ago
1
CREATE executes the code passed to it, andthatcode returns the contact bytecode, yes. Just wanted to be clear on that
– flygoing
2 days ago
1
If you need to a call a function after it's created, then yeah, there would be aCALLright after. Remix is a pretty good way to track/trace on the bytecode level, it has pretty good EVM debugging tools for stepping in/out of bytecode
– flygoing
2 days ago
1
In that case theinitcode would just return the code for your contract. The compiler basically creates adefaultconstructor that does nothing but return the actual bytecode.
– flygoing
yesterday
|
show 1 more comment
CREATE, in a way, does a built in CALL. What actually happens is that the data passed to call isn't the contract bytecode, it's the init bytecode.
When CREATE opcode is executed, the EVM creates a call frame in the context of the new contract (e.g. address(this) is the new contracts address). This executes the data passed to CREATE as the code, which in higher level languages is basically the constructor. At the end of this init stuff, it returns the actual code of the contract that is stored in the state trie.
The easiest way to think about it, which is also fairly accurate, is that the Solidity compiler takes all the executional code of the contract, compiles it to bytecode, and adds it as a return statement at the end of the constructor.
answered 2 days ago
flygoingflygoing
7,595931
ah, so CREATE when creating a contract actually returns the contract bytecode, right? then after that, CALL will actually executes the contract?
– user311703
2 days ago
Please could you tell me what is the best way to track/trace what is really happening at bytecode level? Does Remix a good tool to do this?
– user311703
2 days ago
1
CREATE executes the code passed to it, andthatcode returns the contact bytecode, yes. Just wanted to be clear on that
– flygoing
2 days ago
1
If you need to a call a function after it's created, then yeah, there would be aCALLright after. Remix is a pretty good way to track/trace on the bytecode level, it has pretty good EVM debugging tools for stepping in/out of bytecode
– flygoing
2 days ago
1
In that case theinitcode would just return the code for your contract. The compiler basically creates adefaultconstructor that does nothing but return the actual bytecode.
– flygoing
yesterday
|
show 1 more comment
CREATE, in a way, does a built in CALL. What actually happens is that the data passed to call isn't the contract bytecode, it's the init bytecode.
When CREATE opcode is executed, the EVM creates a call frame in the context of the new contract (e.g. address(this) is the new contracts address). This executes the data passed to CREATE as the code, which in higher level languages is basically the constructor. At the end of this init stuff, it returns the actual code of the contract that is stored in the state trie.
The easiest way to think about it, which is also fairly accurate, is that the Solidity compiler takes all the executional code of the contract, compiles it to bytecode, and adds it as a return statement at the end of the constructor.
answered 2 days ago
flygoingflygoing
7,595931
CREATE, in a way, does a built in CALL. What actually happens is that the data passed to call isn't the contract bytecode, it's the init bytecode.
When CREATE opcode is executed, the EVM creates a call frame in the context of the new contract (e.g. address(this) is the new contracts address). This executes the data passed to CREATE as the code, which in higher level languages is basically the constructor. At the end of this init stuff, it returns the actual code of the contract that is stored in the state trie.
The easiest way to think about it, which is also fairly accurate, is that the Solidity compiler takes all the executional code of the contract, compiles it to bytecode, and adds it as a return statement at the end of the constructor.
answered 2 days ago
flygoingflygoing
7,595931
edited 2 days ago
answered 2 days ago
flygoingflygoing
7,595931
answered 2 days ago
flygoingflygoing
7,595931
answered 2 days ago
flygoingflygoing
7,595931
7,595931
ah, so CREATE when creating a contract actually returns the contract bytecode, right? then after that, CALL will actually executes the contract?
– user311703
2 days ago
Please could you tell me what is the best way to track/trace what is really happening at bytecode level? Does Remix a good tool to do this?
– user311703
2 days ago
1
CREATE executes the code passed to it, andthatcode returns the contact bytecode, yes. Just wanted to be clear on that
– flygoing
2 days ago
1
If you need to a call a function after it's created, then yeah, there would be aCALLright after. Remix is a pretty good way to track/trace on the bytecode level, it has pretty good EVM debugging tools for stepping in/out of bytecode
– flygoing
2 days ago
1
In that case theinitcode would just return the code for your contract. The compiler basically creates adefaultconstructor that does nothing but return the actual bytecode.
– flygoing
yesterday
|
show 1 more comment
ah, so CREATE when creating a contract actually returns the contract bytecode, right? then after that, CALL will actually executes the contract?
– user311703
2 days ago
Please could you tell me what is the best way to track/trace what is really happening at bytecode level? Does Remix a good tool to do this?
– user311703
2 days ago
1
CREATE executes the code passed to it, andthatcode returns the contact bytecode, yes. Just wanted to be clear on that
– flygoing
2 days ago
1
If you need to a call a function after it's created, then yeah, there would be aCALLright after. Remix is a pretty good way to track/trace on the bytecode level, it has pretty good EVM debugging tools for stepping in/out of bytecode
– flygoing
2 days ago
1
In that case theinitcode would just return the code for your contract. The compiler basically creates adefaultconstructor that does nothing but return the actual bytecode.
– flygoing
yesterday
ah, so CREATE when creating a contract actually returns the contract bytecode, right? then after that, CALL will actually executes the contract?
– user311703
2 days ago
ah, so CREATE when creating a contract actually returns the contract bytecode, right? then after that, CALL will actually executes the contract?
– user311703
2 days ago
Please could you tell me what is the best way to track/trace what is really happening at bytecode level? Does Remix a good tool to do this?
– user311703
2 days ago
Please could you tell me what is the best way to track/trace what is really happening at bytecode level? Does Remix a good tool to do this?
– user311703
2 days ago
1
1
CREATE executes the code passed to it, and
that code returns the contact bytecode, yes. Just wanted to be clear on that– flygoing
2 days ago
CREATE executes the code passed to it, and
that code returns the contact bytecode, yes. Just wanted to be clear on that– flygoing
2 days ago
1
1
If you need to a call a function after it's created, then yeah, there would be a
CALL right after. Remix is a pretty good way to track/trace on the bytecode level, it has pretty good EVM debugging tools for stepping in/out of bytecode– flygoing
2 days ago
If you need to a call a function after it's created, then yeah, there would be a
CALL right after. Remix is a pretty good way to track/trace on the bytecode level, it has pretty good EVM debugging tools for stepping in/out of bytecode– flygoing
2 days ago
1
1
In that case the
init code would just return the code for your contract. The compiler basically creates a default constructor that does nothing but return the actual bytecode.– flygoing
yesterday
In that case the
init code would just return the code for your contract. The compiler basically creates a default constructor that does nothing but return the actual bytecode.– flygoing
yesterday
|
show 1 more comment
Thanks for contributing an answer to Ethereum Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fethereum.stackexchange.com%2fquestions%2f68943%2fcreate-opcode-what-does-it-really-do%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
