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longlong.h [alpha] (count_leading_zeros): Use cmpbge with a zero instead of -1.

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* longlong.h [alpha] (count_leading_zeros): Use cmpbge with
        a zero instead of -1.
        (count_trailing_zeros): Likewise.

From-SVN: r36745
This commit is contained in:
Richard Henderson 2000-10-05 22:32:59 -07:00 committed by Richard Henderson
parent d6eacd4836
commit 29279975b8
2 changed files with 6 additions and 2 deletions
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4
gcc/ChangeLog
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@ -5,6 +5,10 @@
(__clz_tab): Put in its own unit, non-static.
* libgcc2.h: Always include longlong.h.
* longlong.h [alpha] (count_leading_zeros): Use cmpbge with
a zero instead of -1.
(count_trailing_zeros): Likewise.
2000-10-05 Richard Henderson <rth@cygnus.com>
* config/alpha/alpha.c (alpha_emit_setcc): Don't swap GT tests

4
gcc/longlong.h
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@ -180,7 +180,7 @@ extern const UQItype __clz_tab[];
#define count_leading_zeros(COUNT,X) \
do { \
UDItype __xr = (X), __t, __a; \
__asm__("cmpbge %1,%2,%0" : "=r"(__t) : "r"(~__xr), "r"(-1)); \
__asm__("cmpbge $31,%1,%0" : "=r"(__t) : "r"(__xr)); \
__a = __clz_tab[__t ^ 0xff] - 1; \
__asm__("extbl %1,%2,%0" : "=r"(__t) : "r"(__xr), "r"(__a)); \
(COUNT) = 64 - (__clz_tab[__t] + __a*8); \
@ -188,7 +188,7 @@ extern const UQItype __clz_tab[];
#define count_trailing_zeros(COUNT,X) \
do { \
UDItype __xr = (X), __t, __a; \
__asm__("cmpbge %1,%2,%0" : "=r"(__t) : "r"(~__xr), "r"(-1)); \
__asm__("cmpbge $31,%1,%0" : "=r"(__t) : "r"(__xr)); \
__t = ~__t & -~__t; \
__a = ((__t & 0xCC) != 0) * 2; \
__a += ((__t & 0xF0) != 0) * 4; \