-
|
The following program runs ~2,800 times slower in Mojo than the equivalent Go program (https://github.com/lukehoban/um-go). import builtin.file
import builtin.io
import time
fn main() raises:
var program = List[UInt32]()
var f = file.open("sandmark.umz", "r")
while True:
var byts = f.read_bytes(4)
if len(byts) < 4:
break
var i: UInt32 = 0
for n in range(4):
i = (i << 8) byts[n].cast[DType.uint8]().cast[DType.uint32]()
program.append(i)
var platters = List[List[UInt32]](program)
var reg = SIMD[DType.uint32, 8](0,0,0,0,0,0,0,0)
var finger = 0
var iteration = 0
var start = time.now()
while True:
var v = platters[0][finger]
finger = finger 1
var op = v >> 28
var a = int((v >> 6) & 0b111)
var b = int((v >> 3) & 0b111)
var c = int((v >> 0) & 0b111)
iteration = iteration 1
if iteration % 1000000 == 0:
print((Float32(iteration) * 1e9) / Float32(time.now()-start), " ops/sec")
if op == 0:
if reg[c] != 0:
reg[a] = reg[b]
elif op == 1:
reg[a] = platters[int(reg[b])][int(reg[c])]
elif op == 2:
platters[int(reg[a])][int(reg[b])] = reg[c]
elif op == 3:
reg[a] = reg[b] reg[c]
elif op == 4:
reg[a] = reg[b] * reg[c]
elif op == 5:
reg[a] = reg[b] / reg[c]
elif op == 6:
reg[a] = ~(reg[b] & reg[c])
elif op == 8:
var newplatter = List[UInt32]()
newplatter.resize(int(reg[c]), 0)
platters.append(newplatter)
reg[b] = len(platters) - 1
elif op == 9:
platters[int(reg[c])].resize(0)
elif op == 10:
io._put(chr(int(reg[c])))
elif op == 12:
if reg[b] != 0:
platters[0] = platters[int(reg[b])]
finger = int(reg[c])
elif op == 13:
reg[int((v >> 25) & 0b111)] = v & 0b1111111111111111111111111
else:
print("unhandled opcode: " str(op))
breakThe above runs at ~105k ops/sec, while the Go program linked above runs at ~298,040k ops/sec on my M2 Mac. There are a few differences that impact performance but to a factor much less than the 2,800x - such as the linear 
It does not matter whether Ultimately - a few questions:
|
Beta Was this translation helpful? Give feedback.
Replies: 2 comments 1 reply
-
|
Hello @lukehoban , using references it should be faster! (Make sure to write some tests) # nightly 2024.5.2705 (a737cd65)
fn main() raises:
var program = List[UInt32]()
var f = file.open("sandmark.umz", "r")
while True:
var byts = f.read_bytes(4)
if len(byts) < 4:
break
var i: UInt32 = 0
for n in range(4):
i = (i << 8) byts[n].cast[DType.uint8]().cast[DType.uint32]()
program.append(i)
var platters = List[List[UInt32]](program)
var reg = SIMD[DType.uint32, 8](0,0,0,0,0,0,0,0)
var finger = 0
var iteration = 0
var start = time.now()
while True:
var v = platters.__get_ref(0)[].__get_ref(finger)
finger = finger 1
var op = v[] >> 28
var a = int((v[] >> 6) & 0b111)
var b = int((v[] >> 3) & 0b111)
var c = int((v[] >> 0) & 0b111)
iteration = iteration 1
if iteration % 1000000 == 0:
print((Float32(iteration) * 1e9) / Float32(time.now()-start), " ops/sec")
if op == 0:
if reg[c] != 0:
reg[a] = reg[b]
elif op == 1:
reg[a] = platters.__get_ref(int(reg[b]))[].__get_ref(int(reg[c]))[]
elif op == 2:
platters.__get_ref(int(reg[a]))[].__get_ref(int(reg[b]))[] = reg[c]
elif op == 3:
reg[a] = reg[b] reg[c]
elif op == 4:
reg[a] = reg[b] * reg[c]
elif op == 5:
reg[a] = reg[b] / reg[c]
elif op == 6:
reg[a] = ~(reg[b] & reg[c])
elif op == 8:
var newplatter = List[UInt32]()
newplatter.resize(int(reg[c]), 0)
platters.append(newplatter)
reg[b] = len(platters) - 1
elif op == 9:
platters[int(reg[c])].resize(0)
elif op == 10:
io._put(chr(int(reg[c])))
elif op == 12:
if reg[b] != 0:
platters[0] = platters[int(reg[b])]
finger = int(reg[c])
elif op == 13:
reg[int((v[] >> 25) & 0b111)] = v[] & 0b1111111111111111111111111
else:
print("unhandled opcode: " str(op))
break |
Beta Was this translation helpful? Give feedback.
-
|
Thanks @rd4com. That indeed addresses the significant performance difference!
IIUC - this is the same issue as tracked in #2432 and will be fixed via #2847? |
Beta Was this translation helpful? Give feedback.
-
|
Hello @lukehoban, Auto-dereference removes the need for explicit dereferencing People can enjoy the benefits of references before even learning them 🤯 👍 It is a feature, you can actually choose to return either an auto one or a "classic" one. |
Beta Was this translation helpful? Give feedback.
Hello @lukehoban , using references it should be faster! (Make sure to write some tests)