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Diffstat (limited to 'core/nds32/__muldi3.S')
| -rw-r--r-- | core/nds32/__muldi3.S | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/core/nds32/__muldi3.S b/core/nds32/__muldi3.S new file mode 100644 index 0000000000..ef4a491183 --- /dev/null +++ b/core/nds32/__muldi3.S @@ -0,0 +1,40 @@ +/* Copyright 2015 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + * + * __muldi3.S: signed 64 bit multiplication + */ + +#define P1H $r1 +#define P1L $r0 +#define P2H $r3 +#define P2L $r2 + + .text + .align 2 + .globl __muldi3 + .type __muldi3, @function +__muldi3: + mul $r5, P1H, P2L ! (ah=a>>31)*(bl=b&0xffffffff) + srli P1H, P1L, 16 ! alh=al>>16 + maddr32 $r5, P1L, P2H ! ah*bl+(bh=b>>31)*(al=a&0xffffffff) + zeh P1L, P1L ! all=al&0xffff + srli P2H, P2L, 16 ! blh=bl>>16 + zeh P2L, P2L ! bll=bl&0xffff + + mul $ta, P1L, P2H ! zA=all*blh + mul $r4, P1L, P2L ! zl=all*bll + mul P2L, P1H, P2L ! zB=alh*bll + add P1L, $ta, P2L ! zA+=zB + slt $ta, P1L, P2L ! zA<zB + slli $ta, $ta, 16 ! (zA<zB)<<16 + slli P2L, P1L, 16 ! zA<<16 + maddr32 $ta, P1H, P2H ! zh=alh*blh+((zA<zB)<<16) + srli P1H, P1L, 16 ! zA>>16 + add P1H, P1H, $ta ! zh+=(zA>>16) + add P1L, $r4, P2L ! zl+=(zA<<16) + slt $ta, P1L, $r4 ! zl<zA + add P1H, P1H, $ta ! zh+=(zl<zA) + add P1H, P1H, $r5 ! zh+=ah*bl+bh*al + ret + .size __muldi3, .-__muldi3 |