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-rw-r--r--stdlib/longlong.h39
1 files changed, 33 insertions, 6 deletions
diff --git a/stdlib/longlong.h b/stdlib/longlong.h
index 197aac41da..4e41ac4a25 100644
--- a/stdlib/longlong.h
+++ b/stdlib/longlong.h
@@ -1,5 +1,5 @@
/* longlong.h -- definitions for mixed size 32/64 bit arithmetic.
- Copyright (C) 1991, 92, 93, 94, 96, 97 Free Software Foundation, Inc.
+ Copyright (C) 1991, 92, 93, 94, 96, 97, 98 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
@@ -1135,12 +1135,39 @@ extern USItype __udiv_qrnnd ();
#define UMUL_TIME 39 /* 39 instructions */
#endif
#ifndef udiv_qrnnd
-#ifndef LONGLONG_STANDALONE
+/* It's quite necessary to add this much assembler for the sparc.
+ The default udiv_qrnnd (in C) is more than 10 times slower! */
#define udiv_qrnnd(q, r, n1, n0, d) \
- do { USItype __r; \
- (q) = __udiv_qrnnd (&__r, (n1), (n0), (d)); \
- (r) = __r; \
- } while (0)
+ __asm__ ("! Inlined udiv_qrnnd
+ mov 32,%%g1
+ subcc %1,%2,%%g0
+1: bcs 5f
+ addxcc %0,%0,%0 ! shift n1n0 and a q-bit in lsb
+ sub %1,%2,%1 ! this kills msb of n
+ addx %1,%1,%1 ! so this can't give carry
+ subcc %%g1,1,%%g1
+2: bne 1b
+ subcc %1,%2,%%g0
+ bcs 3f
+ addxcc %0,%0,%0 ! shift n1n0 and a q-bit in lsb
+ b 3f
+ sub %1,%2,%1 ! this kills msb of n
+4: sub %1,%2,%1
+5: addxcc %1,%1,%1
+ bcc 2b
+ subcc %%g1,1,%%g1
+! Got carry from n. Subtract next step to cancel this carry.
+ bne 4b
+ addcc %0,%0,%0 ! shift n1n0 and a 0-bit in lsb
+ sub %1,%2,%1
+3: xnor %0,0,%0
+ ! End of inline udiv_qrnnd" \
+ : "=&r" ((USItype)(q)), \
+ "=&r" ((USItype)(r)) \
+ : "r" ((USItype)(d)), \
+ "1" ((USItype)(n1)), \
+ "0" ((USItype)(n0)) : "%g1" __AND_CLOBBER_CC)
+#define UDIV_TIME (3+7*32) /* 7 instructions/iteration. 32 iterations. */
extern USItype __udiv_qrnnd __P ((USItype *, USItype, USItype, USItype));
#define UDIV_TIME 140
#endif /* LONGLONG_STANDALONE */