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author | Kevin Ryde <user42@zip.com.au> | 2003-08-19 03:06:31 +0200 |
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committer | Kevin Ryde <user42@zip.com.au> | 2003-08-19 03:06:31 +0200 |
commit | 528f80d0b72a908df43fc9bbe89f05ffec6936d3 (patch) | |
tree | 0e810cc4ede5ac901839d2c69bc879261e677a78 /longlong.h | |
parent | 0955b47bc04d485b91b5699318f6ab594bbda1e1 (diff) | |
download | gmp-528f80d0b72a908df43fc9bbe89f05ffec6936d3.tar.gz |
Amend comments associated with:
* longlong.h (count_trailing_zeros) [x86_64]: Use "%q0" to force
64-bit register destination. Pointed out by Torbjorn.
Diffstat (limited to 'longlong.h')
-rw-r--r-- | longlong.h | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/longlong.h b/longlong.h index c4d0b3005..8baa08c11 100644 --- a/longlong.h +++ b/longlong.h @@ -702,10 +702,7 @@ extern UWtype __MPN(udiv_qrnnd) _PROTO ((UWtype *, UWtype, UWtype, UWtype)); __asm__ ("divq %4" /* stringification in K&R C */ \ : "=a" (q), "=d" (r) \ : "0" ((UDItype)(n0)), "1" ((UDItype)(n1)), "rm" ((UDItype)(dx))) -/* The destination for bsrq and bsfq must be a 64-bit register, hence - UDItype for __cbtmp. And for count_trailing_zeros, the final "count" - variable might be only a 32-bit "int", hence the use of the temporary - there. */ +/* bsrq destination must be a 64-bit register, hence UDItype for __cbtmp. */ #define count_leading_zeros(count, x) \ do { \ UDItype __cbtmp; \ @@ -713,6 +710,8 @@ extern UWtype __MPN(udiv_qrnnd) _PROTO ((UWtype *, UWtype, UWtype, UWtype)); __asm__ ("bsrq %1,%0" : "=r" (__cbtmp) : "rm" ((UDItype)(x))); \ (count) = __cbtmp ^ 63; \ } while (0) +/* bsfq destination must be a 64-bit register, "%q0" forces this in case + count is only an int. */ #define count_trailing_zeros(count, x) \ do { \ ASSERT ((x) != 0); \ |