x86_64 assembly for ecc_384_modp.

diff --git a/ChangeLog b/ChangeLog
index 3b2a590ac02d86da85bb031bb5013df3e69450e2..1bc9b6502fb0016500fd99d8ce84da94564ff405 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,6 @@
 2013-03-06  Niels Möller  <nisse@lysator.liu.se>
 
+       * x86_64/ecc-384-modp.asm: New file, 3 time speedup.
        * x86_64/ecc-256-redc.asm: New file, 2.5 time speedup.
        * x86_64/ecc-224-modp.asm: New file, 5 time speedup over C
        version.

diff --git a/x86_64/ecc-384-modp.asm b/x86_64/ecc-384-modp.asm
new file mode 100644 (file)
index 0000000..698838f
--- /dev/null
+++ b/x86_64/ecc-384-modp.asm
@@ -0,0 +1,240 @@
+C nettle, low-level cryptographics library
+C
+C Copyright (C) 2013 Niels Möller
+C
+C The nettle library is free software; you can redistribute it and/or modify
+C it under the terms of the GNU Lesser General Public License as published by
+C the Free Software Foundation; either version 2.1 of the License, or (at your
+C option) any later version.
+C
+C The nettle library is distributed in the hope that it will be useful, but
+C WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+C or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+C License for more details.
+C
+C You should have received a copy of the GNU Lesser General Public License
+C along with the nettle library; see the file COPYING.LIB.  If not, write to
+C the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+C MA 02111-1301, USA.
+
+       .file "ecc-384-modp.asm"
+
+define(<RP>, <%rsi>)
+define(<D4>, <%rax>)
+define(<T0>, <%rbx>)
+define(<T1>, <%rcx>)
+define(<T2>, <%rdx>)
+define(<T3>, <%rbp>)
+define(<T4>, <%rdi>)
+define(<T5>, <%r8>)
+define(<H0>, <%r9>)
+define(<H1>, <%r10>)
+define(<H2>, <%r11>)
+define(<H3>, <%r12>)
+define(<H4>, <%r13>)
+define(<H5>, <%r14>)
+define(<C2>, <%r15>)
+define(<C0>, H5)       C Overlap
+define(<D0>, RP)       C Overlap
+define(<TMP>, H4)      C Overlap
+
+PROLOGUE(nettle_ecc_384_modp)
+       W64_ENTRY(2, 0)
+
+       push    %rbx
+       push    %rbp
+       push    %r12
+       push    %r13
+       push    %r14
+       push    %r15
+
+       C First get top 2 limbs, which need folding twice
+       C
+       C   H5 H4
+       C     -H5
+       C  ------
+       C   H0 D4
+       C
+       C Then shift right, (H1,H0,D4)  <--  (H0,D4) << 32
+       C and add
+       C
+       C     H5 H4
+       C     H1 H0
+       C ----------
+       C  C2 H1 H0
+
+       mov     80(RP), D4
+       mov     88(RP), H0
+       mov     D4, H4
+       mov     H0, H5
+       sub     H0, D4
+       sbb     $0, H0
+
+       mov     D4, T2
+       mov     H0, H1
+       shl     $32, H0
+       shr     $32, T2
+       shr     $32, H1
+       or      T2, H0
+
+       xor     C2, C2
+       add     H4, H0
+       adc     H5, H1
+       adc     $0, C2
+
+       C Add in to high part
+       add     48(RP), H0
+       adc     56(RP), H1
+       adc     $0, C2          C Do C2 later
+
+       C +1 term
+       mov     (RP), T0
+       add     H0, T0
+       mov     8(RP), T1
+       adc     H1, T1
+       mov     16(RP), T2
+       mov     64(RP), H2
+       adc     H2, T2
+       mov     24(RP), T3
+       mov     72(RP), H3
+       adc     H3, T3
+       mov     32(RP), T4
+       adc     H4, T4
+       mov     40(RP), T5
+       adc     H5, T5
+       sbb     C0, C0
+       neg     C0              C FIXME: Switch sign of C0?
+
+       push    RP
+
+       C +B^2 term
+       add     H0, T2
+       adc     H1, T3
+       adc     H2, T4
+       adc     H3, T5
+       adc     $0, C0
+
+       C   H3 H2 H1 H0  0
+       C - H4 H3 H2 H1 H0
+       C  ---------------
+       C   H3 H2 H1 H0 D0
+
+       mov     XREG(D4), XREG(D4)
+       mov     H0, D0
+       neg     D0
+       sbb     H1, H0
+       sbb     H2, H1
+       sbb     H3, H2
+       sbb     H4, H3
+       sbb     $0, D4
+
+       C Shift right. High bits are sign, to be added to C0.
+       mov     D4, TMP
+       sar     $32, TMP
+       shl     $32, D4
+       add     TMP, C0
+
+       mov     H3, TMP
+       shr     $32, TMP
+       shl     $32, H3
+       or      TMP, D4
+
+       mov     H2, TMP
+       shr     $32, TMP
+       shl     $32, H2
+       or      TMP, H3
+
+       mov     H1, TMP
+       shr     $32, TMP
+       shl     $32, H1
+       or      TMP, H2
+
+       mov     H0, TMP
+       shr     $32, TMP
+       shl     $32, H0
+       or      TMP, H1
+
+       mov     D0, TMP
+       shr     $32, TMP
+       shl     $32, D0
+       or      TMP, H0
+
+       add     D0, T0
+       adc     H0, T1
+       adc     H1, T2
+       adc     H2, T3
+       adc     H3, T4
+       adc     D4, T5
+       adc     $0, C0
+
+       C Remains to add in C2 and C0
+       C                         C0  C0<<32  (-2^32+1)C0
+       C    C2  C2<<32  (-2^32+1)C2
+       C where C2 is always positive, while C0 may be -1.
+       mov     C0, H0
+       mov     C0, H1
+       mov     C0, H2
+       sar     $63, C0         C Get sign
+       shl     $32, H1
+       sub     H1, H0          C Gives borrow iff C0 > 0
+       sbb     $0, H1
+       add     C0, H2
+
+       add     H0, T0
+       adc     H1, T1
+       adc     $0, H2
+       adc     $0, C0
+
+       C Set (H1 H0)  <-- C2 << 96 - C2 << 32 + 1
+       mov     C2, H0
+       mov     C2, H1
+       shl     $32, H1
+       sub     H1, H0
+       sbb     $0, H1
+
+       add     H2, H0
+       adc     C0, H1
+       adc     C2, C0
+       mov     C0, H2
+       sar     $63, C0
+       add     H0, T2
+       adc     H1, T3
+       adc     H2, T4
+       adc     C0, T5
+       sbb     C0, C0
+
+       C Final unlikely carry
+       mov     C0, H0
+       mov     C0, H1
+       mov     C0, H2
+       sar     $63, C0
+       shl     $32, H1
+       sub     H1, H0
+       sbb     $0, H1
+       add     C0, H2
+
+       pop     RP
+
+       sub     H0, T0
+       mov     T0, (RP)
+       sbb     H1, T1
+       mov     T1, 8(RP)
+       sbb     H2, T2
+       mov     T2, 16(RP)
+       sbb     C0, T3
+       mov     T3, 24(RP)
+       sbb     C0, T4
+       mov     T4, 32(RP)
+       sbb     C0, T5
+       mov     T5, 40(RP)
+
+       pop     %r15
+       pop     %r14
+       pop     %r13
+       pop     %r12
+       pop     %rbp
+       pop     %rbx
+
+       W64_EXIT(2, 0)
+       ret
+EPILOGUE(nettle_ecc_384_modp)