diff --git a/src/internal/strconv/itoa.go b/src/internal/strconv/itoa.go index d06de4770f1..2375e034f59 100644 --- a/src/internal/strconv/itoa.go +++ b/src/internal/strconv/itoa.go @@ -174,6 +174,14 @@ func small(i int) string { return smalls[i*2 : i*2+2] } +// RuntimeFormatBase10 formats u into the tail of a +// and returns the offset to the first byte written to a. +// It is only for use by package runtime. +// Other packages should use AppendUint. +func RuntimeFormatBase10(a []byte, u uint64) int { + return formatBase10(a, u) +} + // formatBase10 formats the decimal representation of u into the tail of a // and returns the offset of the first byte written to a. That is, after // diff --git a/src/runtime/print.go b/src/runtime/print.go index e32ecb94503..c01db9d7f98 100644 --- a/src/runtime/print.go +++ b/src/runtime/print.go @@ -140,13 +140,32 @@ func printcomplex64(c complex64) { } func printuint(v uint64) { + // Note: Avoiding strconv.AppendUint so that it's clearer + // that there are no allocations in this routine. + // cmd/link/internal/ld.TestAbstractOriginSanity + // sees the append and doesn't realize it doesn't allocate. var buf [20]byte - gwrite(strconv.AppendUint(buf[:0], v, 10)) + i := strconv.RuntimeFormatBase10(buf[:], v) + gwrite(buf[i:]) } func printint(v int64) { + // Note: Avoiding strconv.AppendUint so that it's clearer + // that there are no allocations in this routine. + // cmd/link/internal/ld.TestAbstractOriginSanity + // sees the append and doesn't realize it doesn't allocate. + neg := v < 0 + u := uint64(v) + if neg { + u = -u + } var buf [20]byte - gwrite(strconv.AppendInt(buf[:0], v, 10)) + i := strconv.RuntimeFormatBase10(buf[:], u) + if neg { + i-- + buf[i] = '-' + } + gwrite(buf[i:]) } var minhexdigits = 0 // protected by printlock