diff options
author | Duncan Wilkie <antigravityd@gmail.com> | 2023-11-18 06:11:09 -0600 |
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committer | Duncan Wilkie <antigravityd@gmail.com> | 2023-11-18 06:11:09 -0600 |
commit | 11da511c784eca003deb90c23570f0873954e0de (patch) | |
tree | e14fdd3d5d6345956d67e79ae771d0633d28362b /gmp-6.3.0/mpn/x86/k7/mmx/rshift.asm |
Initial commit.
Diffstat (limited to 'gmp-6.3.0/mpn/x86/k7/mmx/rshift.asm')
-rw-r--r-- | gmp-6.3.0/mpn/x86/k7/mmx/rshift.asm | 480 |
1 files changed, 480 insertions, 0 deletions
diff --git a/gmp-6.3.0/mpn/x86/k7/mmx/rshift.asm b/gmp-6.3.0/mpn/x86/k7/mmx/rshift.asm new file mode 100644 index 0000000..345d23a --- /dev/null +++ b/gmp-6.3.0/mpn/x86/k7/mmx/rshift.asm @@ -0,0 +1,480 @@ +dnl AMD K7 mpn_rshift -- mpn right shift. + +dnl Copyright 1999-2002 Free Software Foundation, Inc. + +dnl This file is part of the GNU MP Library. +dnl +dnl The GNU MP Library is free software; you can redistribute it and/or modify +dnl it under the terms of either: +dnl +dnl * the GNU Lesser General Public License as published by the Free +dnl Software Foundation; either version 3 of the License, or (at your +dnl option) any later version. +dnl +dnl or +dnl +dnl * the GNU General Public License as published by the Free Software +dnl Foundation; either version 2 of the License, or (at your option) any +dnl later version. +dnl +dnl or both in parallel, as here. +dnl +dnl The GNU MP Library is distributed in the hope that it will be useful, but +dnl WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY +dnl or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +dnl for more details. +dnl +dnl You should have received copies of the GNU General Public License and the +dnl GNU Lesser General Public License along with the GNU MP Library. If not, +dnl see https://www.gnu.org/licenses/. + +include(`../config.m4') + + +C K7: 1.21 cycles/limb (at 16 limbs/loop). + + + +dnl K7: UNROLL_COUNT cycles/limb +dnl 4 1.51 +dnl 8 1.26 +dnl 16 1.21 +dnl 32 1.2 +dnl Maximum possible with the current code is 64. + +deflit(UNROLL_COUNT, 16) + + +C mp_limb_t mpn_rshift (mp_ptr dst, mp_srcptr src, mp_size_t size, +C unsigned shift); +C +C Shift src,size right by shift many bits and store the result in dst,size. +C Zeros are shifted in at the left. The bits shifted out at the right are +C the return value. +C +C This code uses 64-bit MMX operations, which makes it possible to handle +C two limbs at a time, for a theoretical 1.0 cycles/limb. Plain integer +C code, on the other hand, suffers from shrd being a vector path decode and +C running at 3 cycles back-to-back. +C +C Full speed depends on source and destination being aligned, and some hairy +C setups and finish-ups are done to arrange this for the loop. + +ifdef(`PIC',` +deflit(UNROLL_THRESHOLD, 10) +',` +deflit(UNROLL_THRESHOLD, 10) +') + +defframe(PARAM_SHIFT,16) +defframe(PARAM_SIZE, 12) +defframe(PARAM_SRC, 8) +defframe(PARAM_DST, 4) + +defframe(SAVE_EDI, -4) +defframe(SAVE_ESI, -8) +defframe(SAVE_EBX, -12) +deflit(SAVE_SIZE, 12) + + TEXT + ALIGN(32) + +PROLOGUE(mpn_rshift) +deflit(`FRAME',0) + + movl PARAM_SIZE, %eax + movl PARAM_SRC, %edx + subl $SAVE_SIZE, %esp +deflit(`FRAME',SAVE_SIZE) + + movl PARAM_SHIFT, %ecx + movl %edi, SAVE_EDI + + movl PARAM_DST, %edi + decl %eax + jnz L(more_than_one_limb) + + movl (%edx), %edx C src limb + + shrdl( %cl, %edx, %eax) C eax was decremented to zero + + shrl %cl, %edx + + movl %edx, (%edi) C dst limb + movl SAVE_EDI, %edi + addl $SAVE_SIZE, %esp + + ret + + +C ----------------------------------------------------------------------------- +L(more_than_one_limb): + C eax size-1 + C ebx + C ecx shift + C edx src + C esi + C edi dst + C ebp + + movd PARAM_SHIFT, %mm6 C rshift + movd (%edx), %mm5 C src low limb + cmp $UNROLL_THRESHOLD-1, %eax + + jae L(unroll) + leal (%edx,%eax,4), %edx C &src[size-1] + leal -4(%edi,%eax,4), %edi C &dst[size-2] + + movd (%edx), %mm4 C src high limb + negl %eax + + +L(simple_top): + C eax loop counter, limbs, negative + C ebx + C ecx shift + C edx carry + C edx &src[size-1] + C edi &dst[size-2] + C ebp + C + C mm0 scratch + C mm4 src high limb + C mm5 src low limb + C mm6 shift + + movq (%edx,%eax,4), %mm0 + incl %eax + + psrlq %mm6, %mm0 + + movd %mm0, (%edi,%eax,4) + jnz L(simple_top) + + + psllq $32, %mm5 + psrlq %mm6, %mm4 + + psrlq %mm6, %mm5 + movd %mm4, 4(%edi) C dst high limb + + movd %mm5, %eax C return value + + movl SAVE_EDI, %edi + addl $SAVE_SIZE, %esp + emms + + ret + + +C ----------------------------------------------------------------------------- + ALIGN(16) +L(unroll): + C eax size-1 + C ebx + C ecx shift + C edx src + C esi + C edi dst + C ebp + C + C mm5 src low limb + C mm6 rshift + + testb $4, %dl + movl %esi, SAVE_ESI + movl %ebx, SAVE_EBX + + psllq $32, %mm5 + jz L(start_src_aligned) + + + C src isn't aligned, process low limb separately (marked xxx) and + C step src and dst by one limb, making src aligned. + C + C source edx + C --+-------+-------+-------+ + C | xxx | + C --+-------+-------+-------+ + C 4mod8 0mod8 4mod8 + C + C dest edi + C --+-------+-------+ + C | | xxx | + C --+-------+-------+ + + movq (%edx), %mm0 C src low two limbs + addl $4, %edx + movl %eax, PARAM_SIZE C size-1 + + addl $4, %edi + decl %eax C size-2 is new size-1 + + psrlq %mm6, %mm0 + movl %edi, PARAM_DST C new dst + + movd %mm0, -4(%edi) +L(start_src_aligned): + + + movq (%edx), %mm1 C src low two limbs + decl %eax C size-2, two last limbs handled at end + testl $4, %edi + + psrlq %mm6, %mm5 + jz L(start_dst_aligned) + + + C dst isn't aligned, add 4 to make it so, and pretend the shift is + C 32 bits extra. Low limb of dst (marked xxx) handled here separately. + C + C source edx + C --+-------+-------+ + C | mm1 | + C --+-------+-------+ + C 4mod8 0mod8 + C + C dest edi + C --+-------+-------+-------+ + C | xxx | + C --+-------+-------+-------+ + C 4mod8 0mod8 4mod8 + + movq %mm1, %mm0 + psrlq %mm6, %mm1 + addl $32, %ecx C shift+32 + + movd %mm1, (%edi) + movq %mm0, %mm1 + addl $4, %edi C new dst + + movd %ecx, %mm6 +L(start_dst_aligned): + + + movq %mm1, %mm2 C copy of src low two limbs + negl %ecx + andl $-2, %eax C round size down to even + + movl %eax, %ebx + negl %eax + addl $64, %ecx + + andl $UNROLL_MASK, %eax + decl %ebx + + shll %eax + + movd %ecx, %mm7 C lshift = 64-rshift + +ifdef(`PIC',` + call L(pic_calc) +L(here): +',` + leal L(entry) (%eax,%eax,4), %esi + negl %eax +') + shrl $UNROLL_LOG2, %ebx C loop counter + + leal ifelse(UNROLL_BYTES,256,128+) 8(%edx,%eax,2), %edx + leal ifelse(UNROLL_BYTES,256,128) (%edi,%eax,2), %edi + movl PARAM_SIZE, %eax C for use at end + + jmp *%esi + + +ifdef(`PIC',` +L(pic_calc): + C See mpn/x86/README about old gas bugs + leal (%eax,%eax,4), %esi + addl $L(entry)-L(here), %esi + addl (%esp), %esi + negl %eax + + ret_internal +') + + +C ----------------------------------------------------------------------------- + ALIGN(64) +L(top): + C eax size, for use at end + C ebx loop counter + C ecx lshift + C edx src + C esi was computed jump + C edi dst + C ebp + C + C mm0 scratch + C mm1 \ carry (alternating) + C mm2 / + C mm6 rshift + C mm7 lshift + C + C 10 code bytes/limb + C + C The two chunks differ in whether mm1 or mm2 hold the carry. + C The computed jump puts the initial carry in both mm1 and mm2. + +L(entry): +deflit(CHUNK_COUNT, 4) +forloop(i, 0, UNROLL_COUNT/CHUNK_COUNT-1, ` + deflit(`disp0', eval(i*CHUNK_COUNT*4 ifelse(UNROLL_BYTES,256,-128))) + deflit(`disp1', eval(disp0 + 8)) + +Zdisp( movq, disp0,(%edx), %mm0) + psrlq %mm6, %mm2 + + movq %mm0, %mm1 + psllq %mm7, %mm0 + + por %mm2, %mm0 +Zdisp( movq, %mm0, disp0,(%edi)) + + +Zdisp( movq, disp1,(%edx), %mm0) + psrlq %mm6, %mm1 + + movq %mm0, %mm2 + psllq %mm7, %mm0 + + por %mm1, %mm0 +Zdisp( movq, %mm0, disp1,(%edi)) +') + + addl $UNROLL_BYTES, %edx + addl $UNROLL_BYTES, %edi + decl %ebx + + jns L(top) + + +deflit(`disp0', ifelse(UNROLL_BYTES,256,-128)) +deflit(`disp1', eval(disp0-0 + 8)) + + testb $1, %al + psrlq %mm6, %mm2 C wanted rshifted in all cases below + movl SAVE_ESI, %esi + + movd %mm5, %eax C return value + + movl SAVE_EBX, %ebx + jz L(end_even) + + + C Size odd, destination was aligned. + C + C source + C edx + C +-------+---------------+-- + C | | mm2 | + C +-------+---------------+-- + C + C dest edi + C +-------+---------------+---------------+-- + C | | | written | + C +-------+---------------+---------------+-- + C + C mm6 = shift + C mm7 = ecx = 64-shift + + + C Size odd, destination was unaligned. + C + C source + C edx + C +-------+---------------+-- + C | | mm2 | + C +-------+---------------+-- + C + C dest edi + C +---------------+---------------+-- + C | | written | + C +---------------+---------------+-- + C + C mm6 = shift+32 + C mm7 = ecx = 64-(shift+32) + + + C In both cases there's one extra limb of src to fetch and combine + C with mm2 to make a qword to store, and in the aligned case there's + C a further extra limb of dst to be formed. + + + movd disp0(%edx), %mm0 + movq %mm0, %mm1 + + psllq %mm7, %mm0 + testb $32, %cl + + por %mm2, %mm0 + psrlq %mm6, %mm1 + + movq %mm0, disp0(%edi) + jz L(finish_odd_unaligned) + + movd %mm1, disp1(%edi) +L(finish_odd_unaligned): + + movl SAVE_EDI, %edi + addl $SAVE_SIZE, %esp + emms + + ret + + +L(end_even): + + C Size even, destination was aligned. + C + C source + C +---------------+-- + C | mm2 | + C +---------------+-- + C + C dest edi + C +---------------+---------------+-- + C | | mm3 | + C +---------------+---------------+-- + C + C mm6 = shift + C mm7 = ecx = 64-shift + + + C Size even, destination was unaligned. + C + C source + C +---------------+-- + C | mm2 | + C +---------------+-- + C + C dest edi + C +-------+---------------+-- + C | | mm3 | + C +-------+---------------+-- + C + C mm6 = shift+32 + C mm7 = 64-(shift+32) + + + C The movd for the unaligned case is the same data as the movq for + C the aligned case, it's just a choice between whether one or two + C limbs should be written. + + + testb $32, %cl + movd %mm2, disp0(%edi) + + jz L(end_even_unaligned) + + movq %mm2, disp0(%edi) +L(end_even_unaligned): + + movl SAVE_EDI, %edi + addl $SAVE_SIZE, %esp + emms + + ret + +EPILOGUE() |