Add compile time constants for bases 10 and 16 instead of computing the cutoff
value on every invocation of ParseUint by a division.
Reduce usage of slice operations.
amd64:
benchmark old ns/op new ns/op delta
BenchmarkAtoi 44.6 36.0 -19.28%
BenchmarkAtoiNeg 44.2 38.9 -11.99%
BenchmarkAtoi64 72.5 56.7 -21.79%
BenchmarkAtoi64Neg 66.1 58.6 -11.35%
386:
benchmark old ns/op new ns/op delta
BenchmarkAtoi 86.6 73.0 -15.70%
BenchmarkAtoiNeg 86.6 72.3 -16.51%
BenchmarkAtoi64 126 108 -14.29%
BenchmarkAtoi64Neg 126 108 -14.29%
Change-Id: I0a271132120d776c97bb4ed1099793c73e159893
Reviewed-on: https://go-review.googlesource.com/2460
Reviewed-by: Robert Griesemer <gri@golang.org>
Edge cases like base 2 and 36 conversions are now covered.
Many tests are mirrored from the itoa tests.
Added more test cases for syntax errors.
Change-Id: Iad8b2fb4854f898c2bfa18cdeb0cb4a758fcfc2e
Reviewed-on: https://go-review.googlesource.com/2463
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Avoid the decimal lookup in digits array and compute the decimal character value directly.
Reduce calls to 64bit division on 32bit plattforms by splitting conversion into smaller blocks.
Convert value to uintptr type when it can be represented by uintptr.
on darwin/386
benchmark old ns/op new ns/op delta
BenchmarkFormatInt 8352 7466 -10.61%
BenchmarkAppendInt 4281 3401 -20.56%
BenchmarkFormatUint 2785 2251 -19.17%
BenchmarkAppendUint 1770 1223 -30.90%
on darwin/amd64
benchmark old ns/op new ns/op delta
BenchmarkFormatInt 5531 5492 -0.71%
BenchmarkAppendInt 2435 2295 -5.75%
BenchmarkFormatUint 1628 1569 -3.62%
BenchmarkAppendUint 726 750 +3.31%
Change-Id: Ifca281cbdd62ab7d7bd4b077a96da99eb12cf209
Reviewed-on: https://go-review.googlesource.com/2105
Reviewed-by: Robert Griesemer <gri@golang.org>
The new test case produces the longest string representation possible and thereby uses
all of the 65 bytes in the buffer array used by the formatBits function.
Change-Id: I11320c4de56ced5ff098b7e37f1be08e456573e2
Reviewed-on: https://go-review.googlesource.com/2108
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Robert Griesemer
Martin Möhrmann
Rob Pike
Russ Cox