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// picoChip ASM file
//.file "popcounthi2.S"
//
// Support for 16-bit population count.
//
// Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
// Contributed by picoChip Designs Ltd.
// Maintained by Daniel Towner (daniel.towner@picochip.com)
//
// This file is free software; you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option) any
// later version.
//
// In addition to the permissions in the GNU General Public License, the
// Free Software Foundation gives you unlimited permission to link the
// compiled version of this file into combinations with other programs,
// and to distribute those combinations without any restriction coming
// from the use of this file. (The General Public License restrictions
// do apply in other respects; for example, they cover modification of
// the file, and distribution when not linked into a combine
// executable.)
//
// This file is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; see the file COPYING. If not, write to
// the Free Software Foundation, 51 Franklin Street, Fifth Floor,
// Boston, MA 02110-1301, USA.
.section .text
// The following code (taken from a newsgroup posting) was compiled, and then
// hand assembled (a similar version is given in the Hacker's Delight
// book, chapter 5).
//
// int
// popcount (int value)
// {
// value = ((value & 0xAAAA) >> 1) + (value & 0x5555);
// value = ((value & 0xCCCC) >> 2) + (value & 0x3333);
// value = ((value & 0xF0F0) >> 4) + (value & 0x0F0F);
// return ((value & 0xFF00) >> 8) + (value & 0x00FF);
// }
//
// This assembly function is approx. 20x faster than a naive loop
// implementation of the population count, but about 30% bigger
// (45 bytes v. 34 bytes).
.align 8
.global ___popcounthi2
___popcounthi2:
_picoMark_FUNCTION_BEGIN=
// picoChip Function Prologue : &___popcounthi2 = 0 bytes
AND.0 [LSR R0,1],21845,R0 \ AND.1 R0,21845,R5
ADD.0 R0,R5,R0
AND.0 [LSR R0,2],13107,R0 \ AND.1 R0,13107,R5
ADD.0 R0,R5,R0 \ COPY.1 1807,R2
AND.0 [LSR R0,4],R2,R0 \ AND.1 R0,3855,R5
ADD.0 R0,R5,R0
JR (R12) \ AND.0 R0, 255, R5
=-> ADD.0 [LSR R0,8],R5,R0
_picoMark_FUNCTION_END=
// picoChip Function Epilogue : ___popcounthi2
//============================================================================
// All DWARF information between this marker, and the END OF DWARF
// marker should be included in the source file. Search for
// FUNCTION_STACK_SIZE_GOES_HERE and FUNCTION NAME GOES HERE, and
// provide the relevent information. Add markers called
// _picoMark_FUNCTION_BEGIN and _picoMark_FUNCTION_END around the
// function in question.
//============================================================================
//============================================================================
// Frame information.
//============================================================================
.section .debug_frame
_picoMark_DebugFrame=
// Common CIE header.
.unalignedInitLong _picoMark_CieEnd-_picoMark_CieBegin
_picoMark_CieBegin=
.unalignedInitLong 0xffffffff
.initByte 0x1 // CIE Version
.ascii 16#0# // CIE Augmentation
.uleb128 0x1 // CIE Code Alignment Factor
.sleb128 2 // CIE Data Alignment Factor
.initByte 0xc // CIE RA Column
.initByte 0xc // DW_CFA_def_cfa
.uleb128 0xd
.uleb128 0x0
.align 2
_picoMark_CieEnd=
// FDE
_picoMark_LSFDE0I900821033007563=
.unalignedInitLong _picoMark_FdeEnd-_picoMark_FdeBegin
_picoMark_FdeBegin=
.unalignedInitLong _picoMark_DebugFrame // FDE CIE offset
.unalignedInitWord _picoMark_FUNCTION_BEGIN // FDE initial location
.unalignedInitWord _picoMark_FUNCTION_END-_picoMark_FUNCTION_BEGIN
.initByte 0xe // DW_CFA_def_cfa_offset
.uleb128 0x0 // <-- FUNCTION_STACK_SIZE_GOES_HERE
.initByte 0x4 // DW_CFA_advance_loc4
.unalignedInitLong _picoMark_FUNCTION_END-_picoMark_FUNCTION_BEGIN
.initByte 0xe // DW_CFA_def_cfa_offset
.uleb128 0x0
.align 2
_picoMark_FdeEnd=
//============================================================================
// Abbrevation information.
//============================================================================
.section .debug_abbrev
_picoMark_ABBREVIATIONS=
.section .debug_abbrev
.uleb128 0x1 // (abbrev code)
.uleb128 0x11 // (TAG: DW_TAG_compile_unit)
.initByte 0x1 // DW_children_yes
.uleb128 0x10 // (DW_AT_stmt_list)
.uleb128 0x6 // (DW_FORM_data4)
.uleb128 0x12 // (DW_AT_high_pc)
.uleb128 0x1 // (DW_FORM_addr)
.uleb128 0x11 // (DW_AT_low_pc)
.uleb128 0x1 // (DW_FORM_addr)
.uleb128 0x25 // (DW_AT_producer)
.uleb128 0x8 // (DW_FORM_string)
.uleb128 0x13 // (DW_AT_language)
.uleb128 0x5 // (DW_FORM_data2)
.uleb128 0x3 // (DW_AT_name)
.uleb128 0x8 // (DW_FORM_string)
.initByte 0x0
.initByte 0x0
.uleb128 0x2 ;# (abbrev code)
.uleb128 0x2e ;# (TAG: DW_TAG_subprogram)
.initByte 0x0 ;# DW_children_no
.uleb128 0x3 ;# (DW_AT_name)
.uleb128 0x8 ;# (DW_FORM_string)
.uleb128 0x11 ;# (DW_AT_low_pc)
.uleb128 0x1 ;# (DW_FORM_addr)
.uleb128 0x12 ;# (DW_AT_high_pc)
.uleb128 0x1 ;# (DW_FORM_addr)
.initByte 0x0
.initByte 0x0
.initByte 0x0
//============================================================================
// Line information. DwarfLib requires this to be present, but it can
// be empty.
//============================================================================
.section .debug_line
_picoMark_LINES=
//============================================================================
// Debug Information
//============================================================================
.section .debug_info
//Fixed header.
.unalignedInitLong _picoMark_DEBUG_INFO_END-_picoMark_DEBUG_INFO_BEGIN
_picoMark_DEBUG_INFO_BEGIN=
.unalignedInitWord 0x2
.unalignedInitLong _picoMark_ABBREVIATIONS
.initByte 0x2
// Compile unit information.
.uleb128 0x1 // (DIE 0xb) DW_TAG_compile_unit)
.unalignedInitLong _picoMark_LINES
.unalignedInitWord _picoMark_FUNCTION_END
.unalignedInitWord _picoMark_FUNCTION_BEGIN
// Producer is `picoChip'
.ascii 16#70# 16#69# 16#63# 16#6f# 16#43# 16#68# 16#69# 16#70# 16#00#
.unalignedInitWord 0xcafe // ASM language
.ascii 16#0# // Name. DwarfLib expects this to be present.
.uleb128 0x2 ;# (DIE DW_TAG_subprogram)
// FUNCTION NAME GOES HERE. Use `echo name | od -t x1' to get the hex. Each hex
// digit is specified using the format 16#XX#
.ascii 16#5f# 16#5f# 16#70# 16#6f# 16#70# 16#63# 16#6f# 16#75# 16#6e# 16#74# 16#68# 16#69# 16#32# 16#0# // Function name `__popcounthi2'
.unalignedInitWord _picoMark_FUNCTION_BEGIN // DW_AT_low_pc
.unalignedInitWord _picoMark_FUNCTION_END // DW_AT_high_pc
.initByte 0x0 // end of compile unit children.
_picoMark_DEBUG_INFO_END=
//============================================================================
// END OF DWARF
//============================================================================
.section .endFile
// End of picoChip ASM file
|
