diff options
| -rw-r--r-- | mpn/x86/atom/lshift.asm | 93 |
1 files changed, 78 insertions, 15 deletions
diff --git a/mpn/x86/atom/lshift.asm b/mpn/x86/atom/lshift.asm index 67e21e9b2..49a954954 100644 --- a/mpn/x86/atom/lshift.asm +++ b/mpn/x86/atom/lshift.asm @@ -1,8 +1,8 @@ -dnl Intel Atom mpn_lshift -- mpn left shift +dnl Intel Atom mpn_lshift -- mpn left shift. dnl Copyright 2011 Free Software Foundation, Inc. -dnl Converted from AMD64 by Marco Bodrato. +dnl Contributed to the GNU project by Torbjorn Granlund and Marco Bodrato. dnl This file is part of the GNU MP Library. dnl @@ -41,19 +41,30 @@ ASM_START() ALIGN(8) deflit(`FRAME',0) PROLOGUE(mpn_lshift) - movl PARAM_CNT, cnt - movl PARAM_SIZE, %edx - movl up, SAVE_UP - movl PARAM_SRC, up + mov PARAM_CNT, cnt + mov PARAM_SIZE, %edx + mov up, SAVE_UP + mov PARAM_SRC, up push rp FRAME_pushl() - movl PARAM_DST, rp + mov PARAM_DST, rp + +C We can use faster code for shift-by-1 under certain conditions. + cmp $1,cnt + jne L(normal) + cmpl rp, up + jnc L(special) C jump if s_ptr + 1 >= res_ptr + leal (up,%edx,4),%eax + cmpl %eax,rp + jnc L(special) C jump if res_ptr >= s_ptr + size + +L(normal): lea -4(up,%edx,4), up - movl %ebx, SAVE_EBX + mov %ebx, SAVE_EBX lea -4(rp,%edx,4), rp shr %edx mov (up), %eax - movl %edx, VAR_COUNT + mov %edx, VAR_COUNT jnc L(evn) mov %eax, %ebx @@ -65,14 +76,14 @@ PROLOGUE(mpn_lshift) mov %ebx, (rp) jmp L(quit) -L(gt1): movl %ebp, SAVE_EBP +L(gt1): mov %ebp, SAVE_EBP push %eax mov -4(up), %eax mov %eax, %ebp shr %cl, %eax jmp L(lo1) -L(evn): movl %ebp, SAVE_EBP +L(evn): mov %ebp, SAVE_EBP neg cnt mov %eax, %ebp mov -4(up), %edx @@ -86,7 +97,7 @@ L(evn): movl %ebp, SAVE_EBP jz L(end) push %eax FRAME_pushl() - ALIGN(16) + ALIGN(8) L(top): shl %cl, %ebp or %ebp, %edx shl %cl, %ebx @@ -111,13 +122,65 @@ L(end): shl %cl, %ebp shl %cl, %ebx or %ebp, %edx - movl SAVE_EBP, %ebp + mov SAVE_EBP, %ebp mov %edx, -4(rp) mov %ebx, -8(rp) L(quit): - movl SAVE_UP, up - movl SAVE_EBX, %ebx + mov SAVE_UP, up + mov SAVE_EBX, %ebx + pop rp FRAME_popl() + ret + +L(special): +deflit(`FRAME',4) + lea 3(%edx), %eax C size + 3 + dec %edx C size - 1 + mov (up), %ecx + shr $2, %eax C (size + 3) / 4 + and $3, %edx C (size - 1) % 4 + jz L(goloop) C jmp if size == 1 (mod 4) + shr %edx + jnc L(odd) C jum if size == 3 (mod 4) + + add %ecx, %ecx + lea 4(up), up + mov %ecx, (rp) + mov (up), %ecx + lea 4(rp), rp + + dec %edx + jnz L(goloop) C jump if size == 0 (mod 4) +L(odd): lea -8(up), up + lea -8(rp), rp + jmp L(sentry) C reached if size == 2 or 3 (mod 4) + +L(sloop): + adc %ecx, %ecx + mov 4(up), %edx + mov %ecx, (rp) + adc %edx, %edx + mov 8(up), %ecx + mov %edx, 4(rp) +L(sentry): + adc %ecx, %ecx + mov 12(up), %edx + mov %ecx, 8(rp) + adc %edx, %edx + lea 16(up), up + mov %edx, 12(rp) + lea 16(rp), rp + mov (up), %ecx +L(goloop): + decl %eax + jnz L(sloop) + +L(squit): + adc %ecx, %ecx + mov %ecx, (rp) + adc %eax, %eax + + mov SAVE_UP, up pop rp FRAME_popl() ret EPILOGUE() |