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@loredanacirstea
Created May 17, 2020 22:07
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yulToEwasm - for loop bug
========== original source ============
object "TestWasm11" {
code {
datacopy(0, dataoffset("Runtime"), datasize("Runtime"))
return(0, datasize("Runtime"))
}
object "Runtime" {
code {
let len := 4
let result := 5
for { let i := 1 } lt(i, len) { i := add(i, 1) } {
result := add(result, i)
}
mstore(0, result)
return (0, 32)
}
}
}
======= ./tests/contracts/c11.yul (Ewasm) =======
Pretty printed source:
object "TestWasm11" {
code {
{
let _1 := datasize("Runtime")
datacopy(0, dataoffset("Runtime"), _1)
return(0, _1)
}
}
object "Runtime" {
code {
{
let result := 5
let i := 1
let i_1 := i
for { } lt(i_1, 4) { i_1 := add(i_1, i) }
{ result := add(result, i_1) }
mstore(0, result)
return(0, 32)
}
}
}
}
==========================
Translated source:
object "TestWasm11" {
code {
function main()
{
let _1 := datasize("Runtime")
let _2 := 0
let _3:i32 := u256_to_i32(_2, _2, _2, _1)
let _4:i32 := u256_to_i32(_2, _2, _2, dataoffset("Runtime"))
let p:i32 := u256_to_i32(_2, _2, _2, _2)
let r:i32 := i32.add(p, 64:i32)
if i32.lt_u(r, p) { unreachable() }
eth.codeCopy(r, _4, _3)
let _5:i32 := u256_to_i32(_2, _2, _2, _1)
let p_1:i32 := u256_to_i32(_2, _2, _2, _2)
let r_1:i32 := i32.add(p_1, 64:i32)
if i32.lt_u(r_1, p_1) { unreachable() }
eth.finish(r_1, _5)
}
function u256_to_i32(x1, x2, x3, x4) -> v:i32
{
if i64.ne(0, i64.or(i64.or(x1, x2), x3)) { unreachable() }
if i64.ne(0, i64.shr_u(x4, 32)) { unreachable() }
v := i32.wrap_i64(x4)
}
}
object "Runtime" {
code {
function main()
{
let result := 0
let result_1 := result
let result_2 := result
let result_3 := 5
let i := result
let i_1 := result
let i_2 := result
let i_3 := 1
let i_4 := i_3
let _1:i32 := i32.eqz(i32.eqz(i64.eqz(i64.or(i64.or(result, result), i64.or(result, i_3)))))
for { }
i32.eqz(_1)
{
let r4, carry := add_carry(i_4, i_3, 0)
let r3, carry_1 := add_carry(i_2, 0, carry)
let r2, carry_2 := add_carry(i_1, 0, carry_1)
let r1, carry_3 := add_carry(i, 0, carry_2)
i := r1
i_1 := r2
i_2 := r3
i_4 := r4
}
{
let z:i32 := false
switch cmp(i, 0)
case 0:i32 {
switch cmp(i_1, 0)
case 0:i32 {
switch cmp(i_2, 0)
case 0:i32 { z := i64.lt_u(i_4, 4) }
case 1:i32 { z := 0:i32 }
default { z := 1:i32 }
}
case 1:i32 { z := 0:i32 }
default { z := 1:i32 }
}
case 1:i32 { z := 0:i32 }
default { z := 1:i32 }
let _2, _3, _4, _5 := iszero(0, 0, 0, i64.extend_i32_u(z))
if i32.eqz(i64.eqz(i64.or(i64.or(_2, _3), i64.or(_4, _5)))) { break }
let result_4, result_5, result_6, result_7 := add(result, result_1, result_2, result_3, i, i_1, i_2, i_4)
result := result_4
result_1 := result_5
result_2 := result_6
result_3 := result_7
}
mstore(0, 0, 0, 0, result, result_1, result_2, result_3)
return(0, 0, 0, 0, 0, 0, 0, 32)
}
function add_carry(x, y, c) -> r, r_c
{
let t := i64.add(x, y)
r := i64.add(t, c)
r_c := i64.extend_i32_u(i32.or(i64.lt_u(t, x), i64.lt_u(r, t)))
}
function add(x1, x2, x3, x4, y1, y2, y3, y4) -> r1, r2, r3, r4
{
let t := i64.add(x4, y4)
r4 := i64.add(t, 0)
let r3_1, carry := add_carry(x3, y3, i64.extend_i32_u(i32.or(i64.lt_u(t, x4), i64.lt_u(r4, t))))
r3 := r3_1
let r2_1, carry_1 := add_carry(x2, y2, carry)
r2 := r2_1
let r1_1, carry_2 := add_carry(x1, y1, carry_1)
r1 := r1_1
}
function iszero(x1, x2, x3, x4) -> r1, r2, r3, r4
{
r4 := i64.extend_i32_u(i64.eqz(i64.or(i64.or(x1, x2), i64.or(x3, x4))))
}
function cmp(a, b) -> r:i32
{
switch i64.lt_u(a, b)
case 1:i32 { r := 0xffffffff:i32 }
default { r := i64.ne(a, b) }
}
function u256_to_i32(x1, x2, x3, x4) -> v:i32
{
if i64.ne(0, i64.or(i64.or(x1, x2), x3)) { unreachable() }
if i64.ne(0, i64.shr_u(x4, 32)) { unreachable() }
v := i32.wrap_i64(x4)
}
function to_internal_i32ptr(x1, x2, x3, x4) -> r:i32
{
let p:i32 := u256_to_i32(x1, x2, x3, x4)
r := i32.add(p, 64:i32)
if i32.lt_u(r, p) { unreachable() }
}
function endian_swap_16(x) -> y
{
y := i64.or(i64.and(i64.shl(x, 8), 0xff00), i64.and(i64.shr_u(x, 8), 0xff))
}
function endian_swap_32(x) -> y
{
let hi := i64.shl(endian_swap_16(x), 16)
y := i64.or(hi, endian_swap_16(i64.shr_u(x, 16)))
}
function endian_swap(x) -> y
{
let hi := i64.shl(endian_swap_32(x), 32)
y := i64.or(hi, endian_swap_32(i64.shr_u(x, 32)))
}
function mstore(x1, x2, x3, x4, y1, y2, y3, y4)
{
let _1:i32 := to_internal_i32ptr(x1, x2, x3, x4)
i64.store(_1, endian_swap(y1))
i64.store(i32.add(_1, 8:i32), endian_swap(y2))
i64.store(i32.add(_1, 16:i32), endian_swap(y3))
i64.store(i32.add(_1, 24:i32), endian_swap(y4))
}
function return(x1, x2, x3, x4, y1, y2, y3, y4)
{
eth.finish(to_internal_i32ptr(x1, x2, x3, x4), u256_to_i32(y1, y2, y3, y4))
}
}
}
}
Binary representation:
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
Text representation:
(module
;; sub-module "Runtime" will be encoded as custom section in binary here, but is skipped in text mode.
(import "ethereum" "codeCopy" (func $eth.codeCopy (param i32 i32 i32)))
(import "ethereum" "finish" (func $eth.finish (param i32 i32)))
(memory $memory (export "memory") 1)
(export "main" (func $main))
(func $main
(local $_1 i64)
(local $_2 i64)
(local $_3 i64)
(local $_4 i64)
(local $p i64)
(local $r i64)
(local $_5 i64)
(local $p_1 i64)
(local $r_1 i64)
(local.set $_1 (datasize "Runtime"))
(local.set $_2 (i64.const 0))
(local.set $_3 (call $u256_to_i32 (local.get $_2) (local.get $_2) (local.get $_2) (local.get $_1)))
(local.set $_4 (call $u256_to_i32 (local.get $_2) (local.get $_2) (local.get $_2) (dataoffset "Runtime")))
(local.set $p (call $u256_to_i32 (local.get $_2) (local.get $_2) (local.get $_2) (local.get $_2)))
(local.set $r (i64.extend_i32_u (i32.add (i32.wrap_i64 (local.get $p)) (i32.wrap_i64 (i64.const 64)))))
(if (i64.ne (i64.extend_i32_u (i32.lt_u (i32.wrap_i64 (local.get $r)) (i32.wrap_i64 (local.get $p)))) (i64.const 0)) (then
(unreachable)))
(call $eth.codeCopy (i32.wrap_i64 (local.get $r)) (i32.wrap_i64 (local.get $_4)) (i32.wrap_i64 (local.get $_3)))
(local.set $_5 (call $u256_to_i32 (local.get $_2) (local.get $_2) (local.get $_2) (local.get $_1)))
(local.set $p_1 (call $u256_to_i32 (local.get $_2) (local.get $_2) (local.get $_2) (local.get $_2)))
(local.set $r_1 (i64.extend_i32_u (i32.add (i32.wrap_i64 (local.get $p_1)) (i32.wrap_i64 (i64.const 64)))))
(if (i64.ne (i64.extend_i32_u (i32.lt_u (i32.wrap_i64 (local.get $r_1)) (i32.wrap_i64 (local.get $p_1)))) (i64.const 0)) (then
(unreachable)))
(call $eth.finish (i32.wrap_i64 (local.get $r_1)) (i32.wrap_i64 (local.get $_5)))
)
(func $u256_to_i32
(param $x1 i64)
(param $x2 i64)
(param $x3 i64)
(param $x4 i64)
(result i64)
(local $v i64)
(if (i64.ne (i64.extend_i32_u (i64.ne (i64.const 0) (i64.or (i64.or (local.get $x1) (local.get $x2)) (local.get $x3)))) (i64.const 0)) (then
(unreachable)))
(if (i64.ne (i64.extend_i32_u (i64.ne (i64.const 0) (i64.shr_u (local.get $x4) (i64.const 32)))) (i64.const 0)) (then
(unreachable)))
(local.set $v (i64.extend_i32_u (i32.wrap_i64 (local.get $x4))))
(local.get $v)
)
)
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