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Fix as per issue comments

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This commit is contained in:
Vedant Agarwala 2019-05-10 12:11:23 +08:00
parent c0b3da1369
commit ab47864852
1 changed files with 30 additions and 17 deletions
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47
docs/yul.rst
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@ -47,20 +47,21 @@ if the backend changes. For a list of mandatory built-in functions, see the sect
The following example program assumes that the EVM opcodes ``mul``, ``div``
and ``mod`` are available either natively or as functions and computes exponentiation.
As per the warning above, the following code is untyped and can be compiled using ``solc --strict-assembly``.
.. code::
{
function power(base:u256, exponent:u256) -> result:u256
function power(base, exponent) -> result
{
switch exponent
case 0:u256 { result := 1:u256 }
case 1:u256 { result := base }
case 0 { result := 1 }
case 1 { result := base }
default
{
result := power(mul(base, base), div(exponent, 2:u256))
switch mod(exponent, 2:u256)
case 1:u256 { result := mul(base, result) }
result := power(mul(base, base), div(exponent, 2))
switch mod(exponent, 2)
case 1 { result := mul(base, result) }
}
}
}
@ -72,10 +73,10 @@ and ``add`` to be available.
.. code::
{
function power(base:u256, exponent:u256) -> result:u256
function power(base, exponent) -> result
{
result := 1:u256
for { let i := 0:u256 } lt(i, exponent) { i := add(i, 1:u256) }
result := 1
for { let i := 0 } lt(i, exponent) { i := add(i, 1) }
{
result := mul(result, base)
}
@ -593,15 +594,21 @@ An example Yul Object is shown below:
// are in scope without nested access.
object "Contract1" {
code {
function allocate(size) -> ptr {
ptr := mload(0x40)
if iszero(ptr) { ptr := 0x60 }
mstore(0x40, add(ptr, size))
}
// first create "runtime.Contract2"
let size = datasize("runtime.Contract2")
let offset = allocate(size)
let size := datasize("runtime.Contract2")
let offset := allocate(size)
// This will turn into a memory->memory copy for eWASM and
// a codecopy for EVM
datacopy(offset, dataoffset("runtime.Contract2"), size)
// constructor parameter is a single number 0x1234
mstore(add(offset, size), 0x1234)
create(offset, add(size, 32))
pop(create(offset, add(size, 32), 0))
// now return the runtime object (this is
// constructor code)
@ -617,16 +624,22 @@ An example Yul Object is shown below:
object "runtime" {
code {
function allocate(size) -> ptr {
ptr := mload(0x40)
if iszero(ptr) { ptr := 0x60 }
mstore(0x40, add(ptr, size))
}
// runtime code
let size = datasize("Contract2")
let offset = allocate(size)
let size := datasize("Contract2")
let offset := allocate(size)
// This will turn into a memory->memory copy for eWASM and
// a codecopy for EVM
datacopy(offset, dataoffset("Contract2"), size)
// constructor parameter is a single number 0x1234
mstore(add(offset, size), 0x1234)
create(offset, add(size, 32))
pop(create(offset, add(size, 32), 0))
}
// Embedded object. Use case is that the outside is a factory contract,
@ -640,9 +653,9 @@ An example Yul Object is shown below:
code {
// code here ...
}
}
}
data "Table1" hex"4123"
data "Table1" hex"4123"
}
}
}