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586 lines
14 KiB
ArmAsm
586 lines
14 KiB
ArmAsm
1 year ago
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/*
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* Copyright (c) Facebook, Inc.
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* All rights reserved.
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*
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* This source code is licensed under both the BSD-style license (found in the
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* LICENSE file in the root directory of this source tree) and the GPLv2 (found
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* in the COPYING file in the root directory of this source tree).
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* You may select, at your option, one of the above-listed licenses.
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*/
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#include "portability_macros.h"
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/* Stack marking
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* ref: https://wiki.gentoo.org/wiki/Hardened/GNU_stack_quickstart
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*/
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#if defined(__ELF__) && defined(__GNUC__)
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.section .note.GNU-stack,"",%progbits
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#endif
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#if ZSTD_ENABLE_ASM_X86_64_BMI2
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/* Calling convention:
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*
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* %rdi contains the first argument: HUF_DecompressAsmArgs*.
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* %rbp isn't maintained (no frame pointer).
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* %rsp contains the stack pointer that grows down.
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* No red-zone is assumed, only addresses >= %rsp are used.
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* All register contents are preserved.
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*
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* TODO: Support Windows calling convention.
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*/
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ZSTD_HIDE_ASM_FUNCTION(HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop)
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ZSTD_HIDE_ASM_FUNCTION(HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop)
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ZSTD_HIDE_ASM_FUNCTION(_HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop)
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ZSTD_HIDE_ASM_FUNCTION(_HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop)
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.global HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop
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.global HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop
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.global _HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop
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.global _HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop
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.text
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/* Sets up register mappings for clarity.
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* op[], bits[], dtable & ip[0] each get their own register.
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* ip[1,2,3] & olimit alias var[].
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* %rax is a scratch register.
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*/
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#define op0 rsi
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#define op1 rbx
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#define op2 rcx
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#define op3 rdi
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#define ip0 r8
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#define ip1 r9
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#define ip2 r10
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#define ip3 r11
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#define bits0 rbp
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#define bits1 rdx
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#define bits2 r12
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#define bits3 r13
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#define dtable r14
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#define olimit r15
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/* var[] aliases ip[1,2,3] & olimit
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* ip[1,2,3] are saved every iteration.
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* olimit is only used in compute_olimit.
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*/
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#define var0 r15
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#define var1 r9
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#define var2 r10
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#define var3 r11
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/* 32-bit var registers */
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#define vard0 r15d
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#define vard1 r9d
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#define vard2 r10d
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#define vard3 r11d
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/* Calls X(N) for each stream 0, 1, 2, 3. */
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#define FOR_EACH_STREAM(X) \
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X(0); \
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X(1); \
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X(2); \
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X(3)
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/* Calls X(N, idx) for each stream 0, 1, 2, 3. */
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#define FOR_EACH_STREAM_WITH_INDEX(X, idx) \
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X(0, idx); \
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X(1, idx); \
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X(2, idx); \
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X(3, idx)
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/* Define both _HUF_* & HUF_* symbols because MacOS
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* C symbols are prefixed with '_' & Linux symbols aren't.
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*/
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_HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop:
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HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop:
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/* Save all registers - even if they are callee saved for simplicity. */
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push %rax
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push %rbx
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push %rcx
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push %rdx
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push %rbp
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push %rsi
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push %rdi
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push %r8
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push %r9
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push %r10
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push %r11
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push %r12
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push %r13
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push %r14
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push %r15
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/* Read HUF_DecompressAsmArgs* args from %rax */
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movq %rdi, %rax
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movq 0(%rax), %ip0
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movq 8(%rax), %ip1
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movq 16(%rax), %ip2
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movq 24(%rax), %ip3
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movq 32(%rax), %op0
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movq 40(%rax), %op1
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movq 48(%rax), %op2
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movq 56(%rax), %op3
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movq 64(%rax), %bits0
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movq 72(%rax), %bits1
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movq 80(%rax), %bits2
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movq 88(%rax), %bits3
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movq 96(%rax), %dtable
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push %rax /* argument */
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push 104(%rax) /* ilimit */
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push 112(%rax) /* oend */
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push %olimit /* olimit space */
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subq $24, %rsp
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.L_4X1_compute_olimit:
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/* Computes how many iterations we can do safely
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* %r15, %rax may be clobbered
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* rbx, rdx must be saved
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* op3 & ip0 mustn't be clobbered
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*/
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movq %rbx, 0(%rsp)
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movq %rdx, 8(%rsp)
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movq 32(%rsp), %rax /* rax = oend */
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subq %op3, %rax /* rax = oend - op3 */
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/* r15 = (oend - op3) / 5 */
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movabsq $-3689348814741910323, %rdx
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mulq %rdx
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movq %rdx, %r15
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shrq $2, %r15
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movq %ip0, %rax /* rax = ip0 */
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movq 40(%rsp), %rdx /* rdx = ilimit */
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subq %rdx, %rax /* rax = ip0 - ilimit */
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movq %rax, %rbx /* rbx = ip0 - ilimit */
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/* rdx = (ip0 - ilimit) / 7 */
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movabsq $2635249153387078803, %rdx
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mulq %rdx
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subq %rdx, %rbx
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shrq %rbx
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addq %rbx, %rdx
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shrq $2, %rdx
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/* r15 = min(%rdx, %r15) */
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cmpq %rdx, %r15
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cmova %rdx, %r15
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/* r15 = r15 * 5 */
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leaq (%r15, %r15, 4), %r15
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/* olimit = op3 + r15 */
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addq %op3, %olimit
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movq 8(%rsp), %rdx
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movq 0(%rsp), %rbx
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/* If (op3 + 20 > olimit) */
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movq %op3, %rax /* rax = op3 */
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addq $20, %rax /* rax = op3 + 20 */
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cmpq %rax, %olimit /* op3 + 20 > olimit */
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jb .L_4X1_exit
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/* If (ip1 < ip0) go to exit */
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cmpq %ip0, %ip1
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jb .L_4X1_exit
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/* If (ip2 < ip1) go to exit */
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cmpq %ip1, %ip2
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jb .L_4X1_exit
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/* If (ip3 < ip2) go to exit */
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cmpq %ip2, %ip3
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jb .L_4X1_exit
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/* Reads top 11 bits from bits[n]
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* Loads dt[bits[n]] into var[n]
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*/
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#define GET_NEXT_DELT(n) \
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movq $53, %var##n; \
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shrxq %var##n, %bits##n, %var##n; \
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movzwl (%dtable,%var##n,2),%vard##n
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/* var[n] must contain the DTable entry computed with GET_NEXT_DELT
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* Moves var[n] to %rax
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* bits[n] <<= var[n] & 63
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* op[n][idx] = %rax >> 8
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* %ah is a way to access bits [8, 16) of %rax
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*/
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#define DECODE_FROM_DELT(n, idx) \
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movq %var##n, %rax; \
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shlxq %var##n, %bits##n, %bits##n; \
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movb %ah, idx(%op##n)
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/* Assumes GET_NEXT_DELT has been called.
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* Calls DECODE_FROM_DELT then GET_NEXT_DELT
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*/
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#define DECODE_AND_GET_NEXT(n, idx) \
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DECODE_FROM_DELT(n, idx); \
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GET_NEXT_DELT(n) \
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/* // ctz & nbBytes is stored in bits[n]
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* // nbBits is stored in %rax
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* ctz = CTZ[bits[n]]
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* nbBits = ctz & 7
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* nbBytes = ctz >> 3
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* op[n] += 5
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* ip[n] -= nbBytes
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* // Note: x86-64 is little-endian ==> no bswap
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* bits[n] = MEM_readST(ip[n]) | 1
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* bits[n] <<= nbBits
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*/
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#define RELOAD_BITS(n) \
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bsfq %bits##n, %bits##n; \
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movq %bits##n, %rax; \
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andq $7, %rax; \
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shrq $3, %bits##n; \
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leaq 5(%op##n), %op##n; \
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subq %bits##n, %ip##n; \
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movq (%ip##n), %bits##n; \
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orq $1, %bits##n; \
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shlx %rax, %bits##n, %bits##n
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/* Store clobbered variables on the stack */
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movq %olimit, 24(%rsp)
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movq %ip1, 0(%rsp)
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movq %ip2, 8(%rsp)
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movq %ip3, 16(%rsp)
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/* Call GET_NEXT_DELT for each stream */
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FOR_EACH_STREAM(GET_NEXT_DELT)
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.p2align 6
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.L_4X1_loop_body:
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/* Decode 5 symbols in each of the 4 streams (20 total)
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* Must have called GET_NEXT_DELT for each stream
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*/
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FOR_EACH_STREAM_WITH_INDEX(DECODE_AND_GET_NEXT, 0)
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FOR_EACH_STREAM_WITH_INDEX(DECODE_AND_GET_NEXT, 1)
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FOR_EACH_STREAM_WITH_INDEX(DECODE_AND_GET_NEXT, 2)
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FOR_EACH_STREAM_WITH_INDEX(DECODE_AND_GET_NEXT, 3)
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FOR_EACH_STREAM_WITH_INDEX(DECODE_FROM_DELT, 4)
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/* Load ip[1,2,3] from stack (var[] aliases them)
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* ip[] is needed for RELOAD_BITS
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* Each will be stored back to the stack after RELOAD
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*/
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movq 0(%rsp), %ip1
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movq 8(%rsp), %ip2
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movq 16(%rsp), %ip3
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/* Reload each stream & fetch the next table entry
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* to prepare for the next iteration
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*/
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RELOAD_BITS(0)
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GET_NEXT_DELT(0)
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RELOAD_BITS(1)
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movq %ip1, 0(%rsp)
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GET_NEXT_DELT(1)
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RELOAD_BITS(2)
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movq %ip2, 8(%rsp)
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GET_NEXT_DELT(2)
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RELOAD_BITS(3)
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movq %ip3, 16(%rsp)
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GET_NEXT_DELT(3)
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/* If op3 < olimit: continue the loop */
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cmp %op3, 24(%rsp)
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ja .L_4X1_loop_body
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/* Reload ip[1,2,3] from stack */
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movq 0(%rsp), %ip1
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movq 8(%rsp), %ip2
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movq 16(%rsp), %ip3
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/* Re-compute olimit */
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jmp .L_4X1_compute_olimit
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#undef GET_NEXT_DELT
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#undef DECODE_FROM_DELT
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#undef DECODE
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#undef RELOAD_BITS
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.L_4X1_exit:
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addq $24, %rsp
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/* Restore stack (oend & olimit) */
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pop %rax /* olimit */
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pop %rax /* oend */
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pop %rax /* ilimit */
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pop %rax /* arg */
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/* Save ip / op / bits */
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movq %ip0, 0(%rax)
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movq %ip1, 8(%rax)
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movq %ip2, 16(%rax)
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movq %ip3, 24(%rax)
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movq %op0, 32(%rax)
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movq %op1, 40(%rax)
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movq %op2, 48(%rax)
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movq %op3, 56(%rax)
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movq %bits0, 64(%rax)
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movq %bits1, 72(%rax)
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movq %bits2, 80(%rax)
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movq %bits3, 88(%rax)
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/* Restore registers */
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pop %r15
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pop %r14
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pop %r13
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pop %r12
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pop %r11
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pop %r10
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pop %r9
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pop %r8
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pop %rdi
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pop %rsi
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pop %rbp
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pop %rdx
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pop %rcx
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pop %rbx
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pop %rax
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ret
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_HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop:
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HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop:
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||
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/* Save all registers - even if they are callee saved for simplicity. */
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push %rax
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push %rbx
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push %rcx
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push %rdx
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push %rbp
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push %rsi
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push %rdi
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push %r8
|
||
|
|
push %r9
|
||
|
|
push %r10
|
||
|
|
push %r11
|
||
|
|
push %r12
|
||
|
|
push %r13
|
||
|
|
push %r14
|
||
|
|
push %r15
|
||
|
|
|
||
|
|
movq %rdi, %rax
|
||
|
|
movq 0(%rax), %ip0
|
||
|
|
movq 8(%rax), %ip1
|
||
|
|
movq 16(%rax), %ip2
|
||
|
|
movq 24(%rax), %ip3
|
||
|
|
movq 32(%rax), %op0
|
||
|
|
movq 40(%rax), %op1
|
||
|
|
movq 48(%rax), %op2
|
||
|
|
movq 56(%rax), %op3
|
||
|
|
movq 64(%rax), %bits0
|
||
|
|
movq 72(%rax), %bits1
|
||
|
|
movq 80(%rax), %bits2
|
||
|
|
movq 88(%rax), %bits3
|
||
|
|
movq 96(%rax), %dtable
|
||
|
|
push %rax /* argument */
|
||
|
|
push %rax /* olimit */
|
||
|
|
push 104(%rax) /* ilimit */
|
||
|
|
|
||
|
|
movq 112(%rax), %rax
|
||
|
|
push %rax /* oend3 */
|
||
|
|
|
||
|
|
movq %op3, %rax
|
||
|
|
push %rax /* oend2 */
|
||
|
|
|
||
|
|
movq %op2, %rax
|
||
|
|
push %rax /* oend1 */
|
||
|
|
|
||
|
|
movq %op1, %rax
|
||
|
|
push %rax /* oend0 */
|
||
|
|
|
||
|
|
/* Scratch space */
|
||
|
|
subq $8, %rsp
|
||
|
|
|
||
|
|
.L_4X2_compute_olimit:
|
||
|
|
/* Computes how many iterations we can do safely
|
||
|
|
* %r15, %rax may be clobbered
|
||
|
|
* rdx must be saved
|
||
|
|
* op[1,2,3,4] & ip0 mustn't be clobbered
|
||
|
|
*/
|
||
|
|
movq %rdx, 0(%rsp)
|
||
|
|
|
||
|
|
/* We can consume up to 7 input bytes each iteration. */
|
||
|
|
movq %ip0, %rax /* rax = ip0 */
|
||
|
|
movq 40(%rsp), %rdx /* rdx = ilimit */
|
||
|
|
subq %rdx, %rax /* rax = ip0 - ilimit */
|
||
|
|
movq %rax, %r15 /* r15 = ip0 - ilimit */
|
||
|
|
|
||
|
|
/* rdx = rax / 7 */
|
||
|
|
movabsq $2635249153387078803, %rdx
|
||
|
|
mulq %rdx
|
||
|
|
subq %rdx, %r15
|
||
|
|
shrq %r15
|
||
|
|
addq %r15, %rdx
|
||
|
|
shrq $2, %rdx
|
||
|
|
|
||
|
|
/* r15 = (ip0 - ilimit) / 7 */
|
||
|
|
movq %rdx, %r15
|
||
|
|
|
||
|
|
movabsq $-3689348814741910323, %rdx
|
||
|
|
movq 8(%rsp), %rax /* rax = oend0 */
|
||
|
|
subq %op0, %rax /* rax = oend0 - op0 */
|
||
|
|
mulq %rdx
|
||
|
|
shrq $3, %rdx /* rdx = rax / 10 */
|
||
|
|
|
||
|
|
/* r15 = min(%rdx, %r15) */
|
||
|
|
cmpq %rdx, %r15
|
||
|
|
cmova %rdx, %r15
|
||
|
|
|
||
|
|
movabsq $-3689348814741910323, %rdx
|
||
|
|
movq 16(%rsp), %rax /* rax = oend1 */
|
||
|
|
subq %op1, %rax /* rax = oend1 - op1 */
|
||
|
|
mulq %rdx
|
||
|
|
shrq $3, %rdx /* rdx = rax / 10 */
|
||
|
|
|
||
|
|
/* r15 = min(%rdx, %r15) */
|
||
|
|
cmpq %rdx, %r15
|
||
|
|
cmova %rdx, %r15
|
||
|
|
|
||
|
|
movabsq $-3689348814741910323, %rdx
|
||
|
|
movq 24(%rsp), %rax /* rax = oend2 */
|
||
|
|
subq %op2, %rax /* rax = oend2 - op2 */
|
||
|
|
mulq %rdx
|
||
|
|
shrq $3, %rdx /* rdx = rax / 10 */
|
||
|
|
|
||
|
|
/* r15 = min(%rdx, %r15) */
|
||
|
|
cmpq %rdx, %r15
|
||
|
|
cmova %rdx, %r15
|
||
|
|
|
||
|
|
movabsq $-3689348814741910323, %rdx
|
||
|
|
movq 32(%rsp), %rax /* rax = oend3 */
|
||
|
|
subq %op3, %rax /* rax = oend3 - op3 */
|
||
|
|
mulq %rdx
|
||
|
|
shrq $3, %rdx /* rdx = rax / 10 */
|
||
|
|
|
||
|
|
/* r15 = min(%rdx, %r15) */
|
||
|
|
cmpq %rdx, %r15
|
||
|
|
cmova %rdx, %r15
|
||
|
|
|
||
|
|
/* olimit = op3 + 5 * r15 */
|
||
|
|
movq %r15, %rax
|
||
|
|
leaq (%op3, %rax, 4), %olimit
|
||
|
|
addq %rax, %olimit
|
||
|
|
|
||
|
|
movq 0(%rsp), %rdx
|
||
|
|
|
||
|
|
/* If (op3 + 10 > olimit) */
|
||
|
|
movq %op3, %rax /* rax = op3 */
|
||
|
|
addq $10, %rax /* rax = op3 + 10 */
|
||
|
|
cmpq %rax, %olimit /* op3 + 10 > olimit */
|
||
|
|
jb .L_4X2_exit
|
||
|
|
|
||
|
|
/* If (ip1 < ip0) go to exit */
|
||
|
|
cmpq %ip0, %ip1
|
||
|
|
jb .L_4X2_exit
|
||
|
|
|
||
|
|
/* If (ip2 < ip1) go to exit */
|
||
|
|
cmpq %ip1, %ip2
|
||
|
|
jb .L_4X2_exit
|
||
|
|
|
||
|
|
/* If (ip3 < ip2) go to exit */
|
||
|
|
cmpq %ip2, %ip3
|
||
|
|
jb .L_4X2_exit
|
||
|
|
|
||
|
|
#define DECODE(n, idx) \
|
||
|
|
movq %bits##n, %rax; \
|
||
|
|
shrq $53, %rax; \
|
||
|
|
movzwl 0(%dtable,%rax,4),%r8d; \
|
||
|
|
movzbl 2(%dtable,%rax,4),%r15d; \
|
||
|
|
movzbl 3(%dtable,%rax,4),%eax; \
|
||
|
|
movw %r8w, (%op##n); \
|
||
|
|
shlxq %r15, %bits##n, %bits##n; \
|
||
|
|
addq %rax, %op##n
|
||
|
|
|
||
|
|
#define RELOAD_BITS(n) \
|
||
|
|
bsfq %bits##n, %bits##n; \
|
||
|
|
movq %bits##n, %rax; \
|
||
|
|
shrq $3, %bits##n; \
|
||
|
|
andq $7, %rax; \
|
||
|
|
subq %bits##n, %ip##n; \
|
||
|
|
movq (%ip##n), %bits##n; \
|
||
|
|
orq $1, %bits##n; \
|
||
|
|
shlxq %rax, %bits##n, %bits##n
|
||
|
|
|
||
|
|
|
||
|
|
movq %olimit, 48(%rsp)
|
||
|
|
|
||
|
|
.p2align 6
|
||
|
|
|
||
|
|
.L_4X2_loop_body:
|
||
|
|
/* We clobber r8, so store it on the stack */
|
||
|
|
movq %r8, 0(%rsp)
|
||
|
|
|
||
|
|
/* Decode 5 symbols from each of the 4 streams (20 symbols total). */
|
||
|
|
FOR_EACH_STREAM_WITH_INDEX(DECODE, 0)
|
||
|
|
FOR_EACH_STREAM_WITH_INDEX(DECODE, 1)
|
||
|
|
FOR_EACH_STREAM_WITH_INDEX(DECODE, 2)
|
||
|
|
FOR_EACH_STREAM_WITH_INDEX(DECODE, 3)
|
||
|
|
FOR_EACH_STREAM_WITH_INDEX(DECODE, 4)
|
||
|
|
|
||
|
|
/* Reload r8 */
|
||
|
|
movq 0(%rsp), %r8
|
||
|
|
|
||
|
|
FOR_EACH_STREAM(RELOAD_BITS)
|
||
|
|
|
||
|
|
cmp %op3, 48(%rsp)
|
||
|
|
ja .L_4X2_loop_body
|
||
|
|
jmp .L_4X2_compute_olimit
|
||
|
|
|
||
|
|
#undef DECODE
|
||
|
|
#undef RELOAD_BITS
|
||
|
|
.L_4X2_exit:
|
||
|
|
addq $8, %rsp
|
||
|
|
/* Restore stack (oend & olimit) */
|
||
|
|
pop %rax /* oend0 */
|
||
|
|
pop %rax /* oend1 */
|
||
|
|
pop %rax /* oend2 */
|
||
|
|
pop %rax /* oend3 */
|
||
|
|
pop %rax /* ilimit */
|
||
|
|
pop %rax /* olimit */
|
||
|
|
pop %rax /* arg */
|
||
|
|
|
||
|
|
/* Save ip / op / bits */
|
||
|
|
movq %ip0, 0(%rax)
|
||
|
|
movq %ip1, 8(%rax)
|
||
|
|
movq %ip2, 16(%rax)
|
||
|
|
movq %ip3, 24(%rax)
|
||
|
|
movq %op0, 32(%rax)
|
||
|
|
movq %op1, 40(%rax)
|
||
|
|
movq %op2, 48(%rax)
|
||
|
|
movq %op3, 56(%rax)
|
||
|
|
movq %bits0, 64(%rax)
|
||
|
|
movq %bits1, 72(%rax)
|
||
|
|
movq %bits2, 80(%rax)
|
||
|
|
movq %bits3, 88(%rax)
|
||
|
|
|
||
|
|
/* Restore registers */
|
||
|
|
pop %r15
|
||
|
|
pop %r14
|
||
|
|
pop %r13
|
||
|
|
pop %r12
|
||
|
|
pop %r11
|
||
|
|
pop %r10
|
||
|
|
pop %r9
|
||
|
|
pop %r8
|
||
|
|
pop %rdi
|
||
|
|
pop %rsi
|
||
|
|
pop %rbp
|
||
|
|
pop %rdx
|
||
|
|
pop %rcx
|
||
|
|
pop %rbx
|
||
|
|
pop %rax
|
||
|
|
ret
|
||
|
|
|
||
|
|
#endif
|