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Vm bitops fixes (#10520)

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Arne Döring 2019-02-05 09:31:37 +01:00 • committed by Andreas Rumpf
commit 824f39b32e
5 changed files with 47 additions and 62 deletions
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27
lib/pure/bitops.nim
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@ -33,6 +33,18 @@ const useICC_builtins = defined(icc) and useBuiltins
const useVCC_builtins = defined(vcc) and useBuiltins
const arch64 = sizeof(int) == 8
template forwardImpl(impl, arg) {.dirty.} =
when sizeof(x) <= 4:
when x is SomeSignedInt:
impl(cast[uint32](x.int32))
else:
impl(x.uint32)
else:
when x is SomeSignedInt:
impl(cast[uint64](x.int64))
else:
impl(x.uint64)
when defined(nimHasalignOf):
import macros
@ -243,8 +255,7 @@ proc countSetBits*(x: SomeInteger): int {.inline, nosideeffect.} =
# TODO: figure out if ICC support _popcnt32/_popcnt64 on platform without POPCNT.
# like GCC and MSVC
when nimvm:
when sizeof(x) <= 4: result = countSetBits_nim(x.uint32)
else: result = countSetBits_nim(x.uint64)
result = forwardImpl(countSetBits_nim, x)
else:
when useGCC_builtins:
when sizeof(x) <= 4: result = builtin_popcount(x.cuint).int
@ -274,8 +285,7 @@ proc parityBits*(x: SomeInteger): int {.inline, nosideeffect.} =
# Can be used a base if creating ASM version.
# https://stackoverflow.com/questions/21617970/how-to-check-if-value-has-even-parity-of-bits-or-odd
when nimvm:
when sizeof(x) <= 4: result = parity_impl(x.uint32)
else: result = parity_impl(x.uint64)
result = forwardImpl(parity_impl, x)
else:
when useGCC_builtins:
when sizeof(x) <= 4: result = builtin_parity(x.uint32).int
@ -293,8 +303,7 @@ proc firstSetBit*(x: SomeInteger): int {.inline, nosideeffect.} =
when noUndefined:
if x == 0:
return 0
when sizeof(x) <= 4: result = firstSetBit_nim(x.uint32)
else: result = firstSetBit_nim(x.uint64)
result = forwardImpl(firstSetBit_nim, x)
else:
when noUndefined and not useGCC_builtins:
if x == 0:
@ -328,8 +337,7 @@ proc fastLog2*(x: SomeInteger): int {.inline, nosideeffect.} =
if x == 0:
return -1
when nimvm:
when sizeof(x) <= 4: result = fastlog2_nim(x.uint32)
else: result = fastlog2_nim(x.uint64)
result = forwardImpl(fastlog2_nim, x)
else:
when useGCC_builtins:
when sizeof(x) <= 4: result = 31 - builtin_clz(x.uint32).int
@ -360,8 +368,7 @@ proc countLeadingZeroBits*(x: SomeInteger): int {.inline, nosideeffect.} =
if x == 0:
return 0
when nimvm:
when sizeof(x) <= 4: result = sizeof(x)*8 - 1 - fastlog2_nim(x.uint32)
else: result = sizeof(x)*8 - 1 - fastlog2_nim(x.uint64)
result = sizeof(x)*8 - 1 - forwardImpl(fastlog2_nim, x)
else:
when useGCC_builtins:
when sizeof(x) <= 4: result = builtin_clz(x.uint32).int - (32 - sizeof(x)*8)