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feat(std): add isPowerOf2 helper #1348

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Merged
merged 2 commits into from
Jun 20, 2020
Merged

feat(std): add isPowerOf2 helper #1348

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eaf5499
add isPowOfTwo helper
MaxGraey Jun 19, 2020
15a0963
rename isPowOfTwo to isPowerOf2
MaxGraey Jun 19, 2020
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8 changes: 7 additions & 1 deletion std/assembly/util/number.ts
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Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -122,6 +122,12 @@ f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff";
0x9E19DB92B4E31BA9, 0xEB96BF6EBADF77D9, 0xAF87023B9BF0EE6B
]);

// @ts-ignore: decorator
@inline
export function isPowerOf2<T extends number>(value: T): bool {
return popcnt<T>(value) == 1;
}

// Count number of decimals for u32 values
// In our case input value always non-zero so we can simplify some parts
export function decimalCount32(value: u32): u32 {
Expand Down Expand Up @@ -159,7 +165,7 @@ export function decimalCount64High(value: u64): u32 {
}

function ulog_base(num: u64, base: i32): u32 {
if ((base & (base - 1)) == 0) { // if base is pow of two
if (isPowerOf2(base)) {
return (63 - <u32>clz(num)) / (31 - <u32>clz(base)) + 1;
}
var b64 = u64(base), b = b64, e: u32 = 1;
Expand Down
49 changes: 24 additions & 25 deletions tests/compiler/number.untouched.wat
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Original file line number Diff line number Diff line change
Expand Up @@ -418,16 +418,15 @@
end
)
(func $~lib/util/number/ulog_base (param $0 i64) (param $1 i32) (result i32)
(local $2 i64)
(local $2 i32)
(local $3 i64)
(local $4 i32)
(local $4 i64)
(local $5 i32)
local.get $1
local.get $1
local.set $2
local.get $2
i32.popcnt
i32.const 1
i32.sub
i32.and
i32.const 0
i32.eq
if
i32.const 63
Expand All @@ -446,52 +445,52 @@
end
local.get $1
i64.extend_i32_s
local.set $2
local.get $2
local.set $3
i32.const 1
local.get $3
local.set $4
i32.const 1
local.set $5
loop $while-continue|0
local.get $0
local.get $3
local.get $4
i64.ge_u
local.set $5
local.get $5
local.set $2
local.get $2
if
local.get $0
local.get $3
local.get $4
i64.div_u
local.set $0
local.get $3
local.get $3
i64.mul
local.set $3
local.get $4
local.get $4
i64.mul
local.set $4
local.get $5
i32.const 1
i32.shl
local.set $4
local.set $5
br $while-continue|0
end
end
loop $while-continue|1
local.get $0
i64.const 1
i64.ge_u
local.set $5
local.get $5
local.set $2
local.get $2
if
local.get $0
local.get $2
local.get $3
i64.div_u
local.set $0
local.get $4
local.get $5
i32.const 1
i32.add
local.set $4
local.set $5
br $while-continue|1
end
end
local.get $4
local.get $5
i32.const 1
i32.sub
)
Expand Down Expand Up @@ -613,7 +612,7 @@
if
i32.const 32
i32.const 160
i32.const 367
i32.const 373
i32.const 5
call $~lib/builtins/abort
unreachable
Expand Down
51 changes: 25 additions & 26 deletions tests/compiler/resolve-access.untouched.wat
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Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1909,16 +1909,15 @@
end
)
(func $~lib/util/number/ulog_base (param $0 i64) (param $1 i32) (result i32)
(local $2 i64)
(local $2 i32)
(local $3 i64)
(local $4 i32)
(local $4 i64)
(local $5 i32)
local.get $1
local.get $1
local.set $2
local.get $2
i32.popcnt
i32.const 1
i32.sub
i32.and
i32.const 0
i32.eq
if
i32.const 63
Expand All @@ -1937,52 +1936,52 @@
end
local.get $1
i64.extend_i32_s
local.set $2
local.get $2
local.set $3
i32.const 1
local.get $3
local.set $4
i32.const 1
local.set $5
loop $while-continue|0
local.get $0
local.get $3
local.get $4
i64.ge_u
local.set $5
local.get $5
local.set $2
local.get $2
if
local.get $0
local.get $3
local.get $4
i64.div_u
local.set $0
local.get $3
local.get $3
i64.mul
local.set $3
local.get $4
local.get $4
i64.mul
local.set $4
local.get $5
i32.const 1
i32.shl
local.set $4
local.set $5
br $while-continue|0
end
end
loop $while-continue|1
local.get $0
i64.const 1
i64.ge_u
local.set $5
local.get $5
local.set $2
local.get $2
if
local.get $0
local.get $2
local.get $3
i64.div_u
local.set $0
local.get $4
local.get $5
i32.const 1
i32.add
local.set $4
local.set $5
br $while-continue|1
end
end
local.get $4
local.get $5
i32.const 1
i32.sub
)
Expand Down Expand Up @@ -2102,7 +2101,7 @@
if
i32.const 176
i32.const 304
i32.const 395
i32.const 401
i32.const 5
call $~lib/builtins/abort
unreachable
Expand Down Expand Up @@ -2318,7 +2317,7 @@
if
i32.const 176
i32.const 304
i32.const 344
i32.const 350
i32.const 5
call $~lib/builtins/abort
unreachable
Expand Down
49 changes: 24 additions & 25 deletions tests/compiler/resolve-binary.untouched.wat
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -651,16 +651,15 @@
end
)
(func $~lib/util/number/ulog_base (param $0 i64) (param $1 i32) (result i32)
(local $2 i64)
(local $2 i32)
(local $3 i64)
(local $4 i32)
(local $4 i64)
(local $5 i32)
local.get $1
local.get $1
local.set $2
local.get $2
i32.popcnt
i32.const 1
i32.sub
i32.and
i32.const 0
i32.eq
if
i32.const 63
Expand All @@ -679,52 +678,52 @@
end
local.get $1
i64.extend_i32_s
local.set $2
local.get $2
local.set $3
i32.const 1
local.get $3
local.set $4
i32.const 1
local.set $5
loop $while-continue|0
local.get $0
local.get $3
local.get $4
i64.ge_u
local.set $5
local.get $5
local.set $2
local.get $2
if
local.get $0
local.get $3
local.get $4
i64.div_u
local.set $0
local.get $3
local.get $3
i64.mul
local.set $3
local.get $4
local.get $4
i64.mul
local.set $4
local.get $5
i32.const 1
i32.shl
local.set $4
local.set $5
br $while-continue|0
end
end
loop $while-continue|1
local.get $0
i64.const 1
i64.ge_u
local.set $5
local.get $5
local.set $2
local.get $2
if
local.get $0
local.get $2
local.get $3
i64.div_u
local.set $0
local.get $4
local.get $5
i32.const 1
i32.add
local.set $4
local.set $5
br $while-continue|1
end
end
local.get $4
local.get $5
i32.const 1
i32.sub
)
Expand Down Expand Up @@ -843,7 +842,7 @@
if
i32.const 192
i32.const 320
i32.const 367
i32.const 373
i32.const 5
call $~lib/builtins/abort
unreachable
Expand Down
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