On 01/30/2013 09:46 AM, Paolo Bonzini wrote:
>Nevertheless I wonder why you don't use gcc's __builtin_ffsl.
Because I had no idea it existed until now. :)
Do you know what version of GCC introduced it?
gcc 3.4.
2003-02-01 Falk Hueffner <falk.hueff...@student.uni-tuebingen.de>
* optabs.h (optab_index): Add OTI_clz, OTI_ctz, OTI_popcount and
OTI_parity.
(clz_optab, ctz_optab, popcount_optab, parity_optab): New.
* optabs.c (widen_clz, expand_parity): New.
(expand_unop): Handle clz and parity. Hardcode SImode as outmode
for libcalls to clz, ctz, popcount, and parity.
(init_optabs): Init clz_optab, ctz_optab, popcount_optab and
parity_optab, and set up libfunc handlers.
* libgcc2.c (__clzsi2, __clzdi2, __ctzsi2, __ctzdi2,
__popcountsi2, __popcountdi2, __paritysi2 __paritydi2,
__popcount_tab): New.
* libgcc2.h: Declare them.
* libgcc-std.ver (GCC_3.4): Add new functions from libgcc2.c.
* genopinit.c (optabs): Add clz_optab, ctz_optab, popcount_optab
and parity_optab.
* builtin-types.def (BT_FN_INT_LONG, BT_FN_INT_LONGLONG): New.
* builtins.def (BUILT_IN_CLZ, BUILT_IN_CTZ, BUILT_IN_POPCOUNT,
BUILT_IN_PARITY, BUILT_IN_FFSL, BUILT_IN_CLZL, BUILT_IN_CTZL,
BUILT_IN_POPCOUNTL, BUILT_IN_PARITYL, BUILT_IN_FFSLL,
BUILT_IN_CLZLL, BUILT_IN_CTZLL, BUILT_IN_POPCOUNTLL,
BUILT_IN_PARITYLL): New.
...
r~